Confirmation Report >> Literature Review
In a Confirmation Report, the Literature Review contextualises existing research relevant to the research topic to provide a background and rationale for the proposed study. It also evaluates key trends in recent research to highlight their strengths and weaknesses and identify the need for further research, which the proposed study aims to address.
The Literature Review, analyses and evaluates existing research and creates the theoretical foundation to position the proposed study. It fulfils multiple communicative purposes, which are to:
- To identify the central focus and the main research themes of the proposed research
- To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic
- To establish the context for the research gap and identify it
- To justify the approach to the research and show how it will address its objectives.
The following extracts from the Literature Review section of five confirmation reports in Engineering have been annotated to illustrate how these communicative purposes are realised.
Extract A
Function: To identify the central focus and the main research themes of the proposed research
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Protein subcellular localization Note 1 is one of the most essential and indispensable topics in proteomics research. Recent years have witnessed the incredibly fast development of molecular biology and computer science, which makes it possible to utilize computational methods to determine the subcellular locations of proteins. This chapter introduces the background knowledge about proteins Note 2, their subcellular locations Note 3 as well as subcellular localization prediction Note 4 Different conventional methods for subcellular localization prediction are introduced, and finally our proposed methods are outlined. |
| Adapted from: S. Wan. “Protein Subcellular Localization Prediction Based on Gene Ontology and SVM”, PhD confirmation report, Dept. of Elec. and Inf. Eng., POLYU, Hong Kong, 2011. |
Extract B
Function: To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic.
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Advanced oxidation processes (AOPs) involving the generation of hydroxyl radicals (OH∙) as the primary oxidant have been shown to be successful in degrading refractory organic contaminants in waters and wastewaters. Among various AOPs, high-frequency ultrasound (US) has attracted considerable interest in recent years by virtue of its particular comparative advantages such as the avoidance of chemical dosing and catalysts, safety, a lower demand for solution clarity, etc. Note 1 […]. Although US can achieve the degradation of refractory compounds, one of its shortcomings is its relatively low efficiency, mostly due to the inevitable recombination of generated radicals (ca. 80%) to form more stable molecules (H2O2, H2O, etc), which reduces the effective contact between radicals and target contaminants. In order to counter these effects and enhance the oxidation performance by US, its combination with other AOP technologies […] has been tested in an attempt to show either an additive or a synergistic benefit Note 2 The hybrid technique of combining ultraviolet (UV) irradiation and US has been found to be beneficial in enhancing the degradation of target compounds but the majority of previous studies have been conducted under photocatalyst mediated conditions [4-6], which has the disadvantage of incurring the additional costs of the catalysts and their final disposal Note 3. The combination of catalyst-free UV and US (henceforth US/UV), however, has the advantage of Note 4 […]. There is a need for more detailed information concerning the exact role of H2O2 in the treatment reactions and a mechanistic model to describe the US/UV process; these are addressed in this study Note 5. |
| Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014. |
Extract C
To establish the context for the research gap and identify it.
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Among all the methods mentioned above, composition-based methods are easy to implement and have obvious biological reasoning; but in most cases these methods perform poorly, which demonstrates that amino acid sequence information is not sufficient for protein sub-cellular localization. Besides, sorting-signal based methods […] However, this type of methods could only deal with proteins that contain signal sequences. For example, the popular Target P [13], [25], could only detect three locations: chloroplast, mitochondria and secretory pathway (extracellular). Homology-based methods, on the other hand, theoretically can detect as many locations as appeared in the training data and can achieve comparatively high accuracy [26]. Note 1 However, when the training data contains sequences with low sequence similarity or the numbers of samples in different classes are imbalanced, the performance is still very poor. While the functional-domain based methods can often outperform sequence-based methods (as they can leverage the annotations in functional domain databases), they can only be applied to datasets where the sequences possess the required information as so far not all sequences are functionally annotated. Thus, they must be complemented by other types of methods Note 2. |
| Adapted from: S. Wan. “Protein Subcellular Localization Prediction Based on Gene Ontology and SVM”, PhD confirmation report, Dept. of Elec. and Inf. Eng., POLYU, Hong Kong, 2011. |
Extract D
Function: To justify the approach to the research and show how it will address its objectives.
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The aim of the present research is to evaluate the compressive strength and hot working characteristics of the TX32 alloys with a view to understand the effect of the combined additions of Al and Si to TX alloys. Note 1 For this purpose, the compressive strength is measured in the temperature range 25-250 o C and the hot working deformation behaviour is evaluated in the temperature range 300-500 o C by using compression Tests Note 2. |
| Adapted from: D. Chalasani. “Microstructure and Texture Evolution During Hot Working of Mg-3Sn-2Ca (TX32) Alloys With Micro Additions of ‘Al’ and ‘Si’”. PhD confirmation report, Dept. of Manuf. Eng. and Eng. Mgmt., CITYU, Hong Kong, 2011. |
Evaluation and integration of theoretical perspectives and research findings:
Key steps
The evaluation of existing research is a crucial step in a Literature Review, as it allows the author to develop a stance, or an argument that supports their approach to the proposed research. The argument is developed as the author summarises, synthesises, compares and critiques existing research studies. A Literature Review that scopes (i.e. determines what research to include and the extent to which it should be covered) and then incorporates these strategies is more effective compared with one that merely refers to existing research that has been randomly selected.
- Summarising involves the extraction of important findings from a research paper.
- Synthesising refers to the sorting and organisation of important findings selected from existing research and integrating the information into conceptual categories or themes, reflecting the author’s knowledge of the theoretical issues relevant to the topic. This process also involves comparison of perspectives from existing research to highlight similarities and differences.
- Critiquing research involves identifying the limitations or significance of research selected for review and including the author’s original perspectives based on their understanding of research reviewed.
Note:
In critically evaluating previous research, it is more acceptable to criticise and summarise methods than the researchers whose work is reviewed.
The following extracts from a confirmation report in Computer Engineering are used to illustrate these four strategies.
Click on the numbers to see their annotated explanations.
Extract A: Summary and synthesis
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Kupiec et al., (1995) present a medium between the shallow-feature extraction (Edmundson, 1969) and the modern statistical and corpus-based approaches. In the “hiatus” (Hovy, 2005: 583) of over 20 years in between, there were a number of cognitively grounded summarizing systems or models, such as FRUMP (Dejong, 1982) and SCISOR (Jacobs and Rau, 1990) Note 1 They all take semantic representation as input and incorporate complicated knowledge processing, which makes them markedly different from today’s summarizing systems taking text as input and utilizing models and algorithms from AI and NLP Note 2.A more detailed introduction of such efforts can be found in (Endres-Niggemeyer, 1998: 310–330). Ushered in by Kupiec et al., (1995), the age of text summarization has arrived, with upgraded technology (machine learning, statistical, corpus-based, etc.), sharpened tools (lexical cohesion, discourse structure, graph model, etc.), and extended coverage (from single document summarization to multi-document and query-focused summarization) Note 3 |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Extract B: Comparison and critique
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Many summarizing models and systems are traditionally oriented to generic summaries, which do not address a particular US need. On the other hand, query-focused summaries, which are produced in response to a user need or query and related closely to question-answering systems and information extraction techniques (Jurafsky and Martin, 2009: 836-838), have attracted sustained research interest in the past decade Note 1 A pioneering work, (Baldwin and Morton, 1998), addresses an obvious difficulty caused by query — co-reference identification of the key terms in the query. Note 2 A query (or headline) term and its related terms form a co-reference chain, which is used to select sentences for summary. Mani and Bloedorn (1999) report a more complicated query-based MDS system that is built on a standard “analysis-refinement-synthesis” architecture. Note 3 In the analysis stage, documents are represented as graphs with words as nodes and word attributes and relations as edges. In the refinement stage, a spreading activation algorithm is used to reweight the nodes based on the user’s query. Then commonalities and differences between documents are represented as a matrix for sentence extraction. |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Activity 1
The following five extracts are from the Literature Review from confirmation reports in Engineering. Read each extract and from the options that follow it, select its relevant communicative function by placing a tick (✓) in the correct box.
Extract A
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With reference to past and more advanced approaches discussed, this section is intended to draw a large picture of automatic text summarization. […] More technical details will be explored in 2.2 and 2.3, by focusing on both coherence-based and non-coherence-based approaches. |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
To identify the central focus and the main research themes of the proposed research.
To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic.
To establish the context for the research gap and identify it
To justify the approach to the research and show how it will address its objectives.
Check
Extract B
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Current investigations related to Inverse Diffusion Flames (IDF) focus on flame appearance, soot loading and thermal performance. Research on IDF and on the effect on these characteristics by using different fuels is rather limited. To conclude, there is a need to conduct an intensive study to investigate the combustion, thermal and emission characteristics of gas-fired inverse diffusion flame burner burning mixed LPG/H2 fuel. |
| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). |
To identify the central focus and the main research themes of the proposed research
To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic.
To establish the context for the research gap and identify it
To justify the approach to the research and show how it will address its objectives.
Check
Extract C
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A two-stage framework using random forest (FIRF) for fast image interpolation is proposed. By varying the number of decision trees in the random forest and the number of stages applied, the proposed FIRF method can facilitate computational scalable image interpolation Extensive experimental results show that the proposed FIRF method achieves 1.3 dB improvement over the bicubic interpolation and is better or comparable with the state-of-the-art nonlocal autoregressive modeling with sparse representation model (NARM) method. |
| Adapted from: J.J. Huang. “On Object Recognition and Quality Inspection for Video Surveillance Systems”, PhD confirmation report, Dept. of Dept. of Elec. and Inf. Eng., POLYU, Hong Kong (No date). |
To identify the central focus and the main research themes of the proposed research
To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic.
To establish the context for the research gap and identify it
To justify the approach to the research and show how it will address its objectives.
Check
Extract D
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Lapata and Barzilay (2005) experiment with various mainstream theories and models in coherence evaluation, broadly categorized as syntactic models and semantic models. The syntactic model is based on (Barzilay and Lapata, 2005) that captures the local coherence through entity transitions. The semantic models do not concern syntactic structure or even word order. They compare three types of models: word-based (word overlap) models, LSA (distributional similarity) models, and WordNet-based (taxonomical similarity) models. The experimental results show that individually, the models that are most highly correlated with human assessment are the entity grid, the LSA (Foltz et al., 1998), and two WordNet-based models (Hirst and St-Onge, 1998; Jiang and Conrath, 1997). Collectively, the combination of the entity grid, word-overlap, LSA, Hirst and St-Onge, and Lesk (1986) models is the optimal solution. |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
To identify the central focus and the main research themes of the proposed research
To critically evaluate and integrate theoretical perspectives and research findings relevant to the research topic.
To establish the context for the research gap and identify it
To justify the approach to the research and show how it will address its objectives.
CheckIn a Confirmation Report, information in the Literature Review is structured to fulfill the communicative purposes of this section. The goals of the proposed research are an important consideration in developing the structure of the review, as the discussion of existing research needs to be organised in relation to these objectives.
As a Literature Review covers multiple themes, conveying a coherent and integrated message about the proposed study could pose a challenge for the author. Authors hence tend to structure the review into three sections: an introduction, a body section and a conclusion, each with its own specific purpose.
The introductory section outlines the scope of the Literature Review (i.e. the information it includes), rationalises the need for more research on the topic, makes a claim about the proposed research, and outlines the organisation of the chapter.
The review and evaluation of research, the identification of the research gap and a brief outline of the methods adopted to achieve the aims of the research are included in the main body.
The conclusion summarises the main themes discussed, presents the research questions and offers a brief explanation of how the methods adopted answer these questions.
The Table of Contents (TOC) page from a confirmation report in Mechanical Engineering is used to illustrate this three-section structural pattern.
Following this, these three sections are illustrated using extracts from two confirmation reports in Engineering.
TOC from Report A: The three-section pattern of organisation
The research investigates the combustion, emission and thermal characteristics of gas-fired inverse diffusion flames burning a mixed LPG-H2 fuel.
Chapter 2 Literature Review |
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14 |
2.1 Introduction
2.1- 2.4 Main Body
2.5 Conclusion
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2.1 Introduction |
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14 |
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2.2 Flame |
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14 |
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2.2.1 Premixed Flame |
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15 |
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2.2.2 Diffusion |
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18 |
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2.2.3 Impinging Flames |
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22 |
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2.2.4 Inverse Diffusion Flame |
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26 |
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2.3 Fuels |
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34 |
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2.3.1 LPG Fuel |
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34 |
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2.3.2 Hydrogen Enriched Fuel |
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36 |
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2.4 Numerical simulation |
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39 |
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2.5 Summary |
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41 |
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| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). | |||
The structural organisation for a Literature Review can be represented by the following chart. Note how it is similar to the TOC from the above report, which includes three themes: flame, fuels and numerical simulation.
Note: Parts of the original text included in the below extract are in italics.
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1.1 Introduction to the Literature Review This project aims to analyze the heat transfer characteristics of hydrogen enriched LPG inverse diffusion flame. The literature about flame and fuels is comprehensively reviewed for the experiment. Inverse diffusion flame, diffusion flame and premixed flame are studied. In addition, the characteristics of impinging flame were studied to support further research on temperature distribution of impinging inverse diffusion flame. The major fuels used in this project, LPG and hydrogen, and LPG flame and hydrogen-enriched flame are examined. The literature review will include an introduction of flame and flame category, description of premix and diffusion flame and information about impinging flame. Inverse diffusion flame will be comprehensively reviewed and LPG flame and hydrogen-enriched flame will be introduced. 1.2 Theme 1 Introductory sentences to state what this subsection is about In the following sections, features of premixed flame, diffusion flame, impinging flame and inverse diffusion flame will be discussed. Transition to the next section 1.3 Theme 2 A mixture of fuels was applied to analyse the inverse diffusion flame. The fuels include commercial LPG fuel with varying hydrogen percentages and hydrogen fuel. Basic information and previous research on LPG and Hydrogen will be introduced in the following sections. Transition to the next section 2.n etc. 2.n+1 Conclusion From the above literature review, it can be concluded that inverse diffusion flame, as a special kind of diffusion flame, still needs further investigation. Heat transfer characteristics such as flame structure, temperature distribution and pollution emission volume are essential information in flame research. Similarly, the characteristics of inverse diffusion flame contains need further investigation. More experimental studies are required in the progression of flame science. |
| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). |
The introduction section to the Literature Review is annotated below to identify the main aspects.
Extract A (Introduction)
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The literature review section of this report introduces the concepts of combustion fuel, flame, mixed fuels and flame category Note 1. It provides a detailed description of premixed flame, diffusion flame and impinging flame Note 2. It includes a comprehensive review of research on inverse diffusion flame, LPG flame and hydrogen-enriched flame Note 3. |
| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). |
The Conclusion or Summary section of the Literature Review serves to draw together the main themes discussed. Apart from providing such a summary, it could also:
- indicate how the main themes discussed link to the research gap and its solution(s),
- state the rationale for the research
- include a transition statement showing how the Literature Review transitions to the next section (Methods).
The conclusion to the Literature Review from the same confirmation report is annotated below to identify the main aspects.
Extract B (Conclusion or Summary)
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From the above literature review, it can be concluded that inverse diffusion flame, as a special kind of diffusion flame, still needs further investigation. Note 1 Heat transfer characteristics such as flame structure, temperature distribution and pollution emission volume are essential information in flame research and such information is not available for inverse diffusion flames. Note 2The experiments in this project will analyse the effect of hydrogen addition on:
Flame structures with varying hydrogen percentages will be tested. The detailed experiment setup to investigate these flame structures will be explained in Chapter 3, Research Methodology. Note 4 |
| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). |
The Literature Review discusses the specific aspects of LPG fueled IDF (flame structure, temperature distribution and pollution emission volumes) and experiments designed to assess these aspects (1-4) will be detailed in Chapter 3, Research Methodology.
In the main body of the Literature Review, information generally included covers:
- Background information and historical perspectives on the topic
- Theoretical viewpoints or assumptions, product or system designs, models or algorithms and their relevance to the research focus
- Recent trends and findings relevant to the research topic
- The author’s argument or stance about existing research
- The research gap
- The contribution of the study
The extract below from a section of the Literature Review from a confirmation report in Civil and Environmental Engineering, illustrates some of the key aspects included in the main body of a Literature Review. The study investigates advanced oxidation processes (AOPs) for degrading organic contaminants in waters and wastewaters.
Extract C
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Dimethyl phthalate (DMP) was selected as the model compound for this study since it is an anthropogenic contaminant of environmental concern and relatively recalcitrant to degradation in the environment. It is one of the most common phthalate esters, which are a group of industrially important chemicals, widely employed as plasticizers and additives to improve the mechanical properties and flexibility of various products. However, DMP has been listed as a priority pollutant by the U.S. Environmental Protection Agency (USEPA) owing to its toxicological properties. Substantial quantities of DMP are released into environmental water bodies through the disposal of manufacturing wastewater and from direct leaching from plastic products, leading to its widespread occurrence and potential risks on the health of humans and wildlife. Note 1 Various methods of treating DMP by AOPs have been investigated in recent years, such as O3/H2O2, [11] O3/UV[8] , TiO2-UV[12], and Fe(VI)-TiO2-UV, [13] and a limited number of studies have considered the sonolytic degradation of DMP, proposing the dominant role of OH∙ radical oxidation [14,15]. Note 2 However, the potential enhancement of DMP degradation by the combination of US with UV (sonophotolysis) has not been reported so far. Note 3 In view of the above, the main interest of this study is to ascertain the main mechanism of the hybrid process of US/UV in the absence of any catalyst with DMP as a chosen probe. Note 4 The contribution of H2O2 is examined both qualitatively and quantitatively, and a novel inverted S-curve degradation model is proposed to describe the hybrid process. Note 5 |
| Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014. |
Moves in the Literature Review
The structure of the Literature Review is developed when the author includes key aspects of information, making six key moves:
- Identifying the research topic and its main themes.
- Presenting relevant theoretical viewpoints, product or system designs, models and algorithms.
- Reviewing and evaluating relevant research
- Developing an argument or stance about existing research.
- Identifying the research gap.
- Stating the contribution of the study.
A Literature Review might not include all the moves listed above. For example, some writers do not make an explicit reference to the contribution of the study as they might have already covered it in the Introduction. On the other hand, some of the moves may appear more than once because the writer needs to present a number of relevant theoretical viewpoints. You are advised to check departmental requirements for this section of your confirmation report with your supervisor.
Information in a Literature Review: Selection criteria and organisational structures
A Literature Review details, evaluates and synthesises several perspectives on multiple themes. The complex and extensive information thus provided can only be processed easily if the content is selected appropriately (in terms of relevance to the research topic and research objectives) and organised using a logical and coherent structural pattern.
Guiding principles for selecting information for this section are:
- Literature selected should be of a high quality and be relevant to the proposed research, and be as recent as possible.
- The information must have relevance in terms of advancing the author’s argument or position about existing research.
- It should allow the author to identify the research gap.
Options for organising information in the Literature Review
This information can either be organised from the general to the specific, or, in a study with multiple themes, according to themes or sub-topics. Each theme or sub-topic is then discussed following the general to specific pattern of organisation. The following Table of Contents pages from two confirmation reports in Engineering illustrates these two structural patterns.
Click the buttons ‘Explanation for Report A’ and ‘Explanation for Report B’ to see the structure for each report explained.
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Confirmation Report A: General to specific structural pattern* |
Confirmation Report B: Theme/sub-topic based structural pattern** |
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Fabrication of Novel Optical Fibers and their Application |
Protein Subcellular Localization Prediction Based on Gene Ontology and SVM |
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2. Fabrication of PCF |
2. Functional-Domain vs Homology-Based Methods 3. GOASVM Method |
| * Adapted from: Z. Liu. “Fabrication of Novel Optical Fibers and their Application”, PhD confirmation report, Dept. of Elec. Eng., POLYU, Hong Kong, (No date). ** Adapted from: S. Wan. “Protein Subcellular Localization Prediction Based on Gene Ontology and SVM”, PhD confirmation report, Dept. of Elec. and Inf. Eng., POLYU, Hong Kong, 2011. |
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Structural organisation: Linking the Literature Review to the Introduction
The structure of the Literature Review is also guided by the Introduction, as it should demonstrate coherent and logical development using key points from the brief review of relevant research presented in the Introduction. The Introduction presents an overall picture of the research with reference to its theoretical foundation, its rationale, objectives and contribution to the field. However, the Literature Review develops the theoretical basis introduced in the Introduction to create theoretical arguments that support the objectives of the research in addressing the research gap, which are identified in the broader review of the Introduction. This link is illustrated in the following activity.
Activity 1>> 2
The extract below features an edited Introduction (Column A) and the Table of Contents (TOC) for the Literature Review from a Confirmation Report in Computer Engineering. The research is entitled ‘Coherence-based text summarisation’. The edited Introduction, which also follows the ‘general to specific’ structural pattern (text summarisation →coherence based summarisation), provides the contextual background for the TOC.
Click on the highlighted sections to see their explanation.
Click on the button ‘Structure’ at the end of the extract to see an explanation for the structural organisation of the Literature Review.
Note: […] indicates sections deleted due to space constraints.
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Column A (edited Introduction) |
Column B (Table of Contents for the Literature Review) |
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This project examines coherence-based text summarisation, which is distinguished from general summarization research in its emphasis on coherence. The concern with coherence is motivated by the purpose of automatic text summarization—to provide human readers with a sufficiently abridged summary of a long document or document set to facilitate efficient information processing. In this sense, the summary serves as a surrogate for the original document(s) in terms of informativeness and expressiveness. Informatively, the summary is expected to maximally reproduce the original document in less space. Expressively, it is expected to convey the information in an intelligible and coherent way to human users. In the past, informativeness has been greatly emphasized, leading to increasingly sophisticated models, algorithms, and evaluation methods. However, a summary’s quality easily understood (expressiveness,) is equally important. A deciding factor for the expressiveness of a summary is coherence, i.e., how well textual components such as sentences are connected to each other and together in the whole text […] In sum, the goal of this project is to enhance the expressiveness of automatic summaries by instilling coherence into the mainstream summarization frameworks on different levels […]. It is expected that […]. |
2.1 An overview of text summarisation 2.2 Non coherence-based approaches 2.3 Coherence based approaches
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| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. | |
Explanation of Structure
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The following table lists five extracts from the Literature Review section of a selection of confirmation reports in Column A. From the list of options below, select the relevant option that describes the move the author makes in the extract.
Click on the box ‘Check answer’ to see the pop-up extract and the move explained.
| Extracts | MC Options | Correct Answer |
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Extract A | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
The research focuses on advanced oxidation processes to degrade contaminants in waters and wastewaters. The author makes the argument that catalyst-free US/UV treatments can address the shortcomings of previous studies, [4-6] which were carried out in photocatalyst mediated conditions.
Check |
Move: Developing an argument or stance about existing research. |
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Extract B | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
The research investigates extending applications of HFAC beyond low-power grid systems. The extract identifies the potential contribution of the research in terms of high power systems that are flexible and generate higher power outputs.
Check |
Move: Stating the contribution of the study |
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Extract C | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
The research focuses on advanced oxidation processes and specifically examines the high-frequency ultrasound process.
Check |
Move: Identifying the research topic and its main themes. |
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Extract D | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
In this extract, research on wrought alloys (Mg-Sn- Ca, Al and Si) is reviewed to make the argument that Mg-Sn-Ca-Al-Si alloys can address the gap (the drawbacks of the TX series, or Mg-Sn- Ca alloys).
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Move: Reviewing and evaluating relevant research to develop an argument or stance about existing research. |
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Extract E | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
The review highlights the lack of information on certain aspects of high-frequency AC power distribution systems and identifies areas that need to be investigated (EMC standards, transformer design, power factor connection, waveforms of the distribution, the optimized bus structure for high frequency application, modeling analysis and design of the system and AC-DC direct power conversion), and draws attention to the need for improving the design of measurement technology.
Check |
Move: Identifying the research gap. |
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Extract F | Identifying the research topic and its main themes. Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. Reviewing and evaluating relevant research to develop an argument or stance about existing research. Identifying the research gap. Developing an argument or stance about existing research. Stating the contribution of the study.
Move:
Move: Presenting relevant theoretical viewpoints, product or system designs, models and algorithms.
This extract presents the theoretical rationale for why gene ontology (GO) terms for cellular component ontology ‘cannot be used to annotate the subcellular locations of proteins’.
Check |
Move: Presenting relevant theoretical viewpoints, product or system designs, models and algorithms. |
* Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014.
** Adapted from J. Liu. “Investigation of Power Conversion and Control Scheme for High Frequency AC Power Distribution System”, PhD confirmation report, Dept. of Elect. Eng., POLYU, Hong Kong (No date).
*** Adapted from: D. Chalasani. “Microstructure and Texture Evolution During Hot Working of Mg-3Sn-2Ca (TX32) Alloys With Micro Additions of ‘Al’ and ‘Si’”. PhD confirmation report, Dept. of Manuf. Eng. and Eng. Mgmt., CITYU, Hong Kong, 2011.
**** Adapted from: S. Wan. “Protein Subcellular Localization Prediction Based on Gene Ontology and SVM”, PhD confirmation report, Dept. of Elec. and Inf. Eng., POLYU, Hong Kong, 2011.
In a confirmation report, the Literature Review contextualises existing research relevant to the research topic to provide a background and rationale for the proposed study. It also evaluates key trends in recent research to highlight their strengths and weaknesses and identify the need for further research contextualizing the proposed research. This section covers important aspects of language use in the Literature Review, which are required to fulfil its communicative functions.
The main aspects of language use covered in this section are:
- Verb tenses in the Literature Review
- Language use: constructing an argument/taking a stance (evaluative language, language use for summarisation, synthesis, comparison and critique).
- Linking sections: Inter and intra paragraph coherence
- Writing about the Literature Review: Transition and overview statements
Verb tenses in the Literature Review
In the Literature Review, verb tenses are mainly used for the following functions:
- To identify and discuss the main themes relevant to the proposed research
- To review and critically evaluate relevant research
- To identify the research gap
- To justify the approach to the research and show how it will address its objectives.
To achieve these functions, a combination of verb tenses is used as illustrated below.
- Present tense is used to refer to a process, a fact or information established as a fact in the field. The following extract illustrates the use of this tense.
Extract A
The first batch of systems, spanning the time period 1980-1990, typically incorporates 1text understanding and knowledge engineering techniques, which is 2 motivated by theories about human cognition in summarization […]. Internal representations as the product of deep semantic and/or pragmatic analysis are 3 invariably used for further processing. Another noticeable feature shared by those systems is 4 that they do not distinguish 5 “abstract” from “extract”, as human-like output (i.e. abstract) is 6 the only goal they pursue.
Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010.
- Present perfect tense (has/have + ed) is used to summarise or make general statements about relevant research or trends, without specifying a time period. This tense has multiple functions as follows:
Function
Example
To provide information or facts to create a background for the topic
Laser deflection techniques have been used in flame research for a considerable length of time. *
To provide background information about past research procedures.
Scientists have concentrated on the detailed study of diffusion flame, such as flame height, flame shape, lifted diffusion flame, flame stability and flame pollution emission.*
To provide a brief overview of the present state of research
More recent approaches aimed at sentence compression have relied on supervised machine learning by using parallel document/summary corpora. **
To provide a general summary of main trends without identifying a particular article.
Although US can achieve the degradation of refractory compounds, one of its shortcomings is […], which reduces the effective contact between radicals and target contaminants. In order to counter these effects and enhance the oxidation performance by US, its combination with other AOP technologies (photocatalysis, Fenton process, ozonation, etc) has been tested in an attempt to show either an additive or a synergistic benefit. The hybrid technique of combining ultraviolet (UV) irradiation and US has been found to be beneficial in enhancing the degradation of target compounds but the majority of previous studies have been conducted under photocatalyst mediated conditions […].***
* Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date).
** Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010.
*** Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014.
- Present continuous tense is used to refer to a currently developing, ongoing situation where the emphasis is on the present time. It is different from the present perfect tense which details an unspecified period of time.
Extract B
Even though LPG is a clean fuel because of its low ash and sulphur content, the emission of dioxide (CO2) is still causing environmental problems resulting from the emission of greenhouse gases.
Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date).
- Past tense is used to refer to outcomes of previous research or finished events within a specific time period..
Extract C
Dimethyl phthalate (DMP) was selected as the model compound for this study since it is an anthropogenic contaminant of environmental concern and relatively recalcitrant to degradation in the environment. Note 1*
Kizirnis et al. used laser deflection techniques to measure hydroxyl (OH) distribution and temperature distribution in a premixed flame. They imaged the flame with both high and low spatial resolutions and proved that laser deflection technology led to no significant perturbation on flame performance. Note 2**
* Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014.
** Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date).
Language use: constructing an argument/taking a stance
An effective literature review goes beyond demonstrating the author’s knowledge of relevant research – it also includes the author’s argument or stance in relation to the research reviewed. Stance is revealed through the use of hedging expressions (words that reduce the strength of one’s claim), boosters (words that strengthen a claim) and attitude markers (words that signal the author’s attitude towards research reviewed).
Evaluative language
The main objective in citing other researchers’ work in the Literature Review is to analyse and evaluate existing research to situate the proposed research and justify it as an answer to the research gap. This process of analysis and evaluation also enables the author to establish their stance towards the research that is being cited. In order to fulfil these objectives, authors use the following language features:
Language features that signal evaluation (adjectives and adverbs)
Attitudinal expressions (phrases that signal the author’s attitude)
Here are some examples of evaluative language (highlighted in green) from Confirmation Reports in Engineering. They identify inadequacies in previous research and lead into the research gap, and also signal the author’s stance towards current research.
Click on the numbers in superscript (Note 1-8) to see each example of evaluative language explained.
Key: Evaluatory language
Extract B
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Although high-frequency ultrasound (US) can achieve the degradation of refractory compounds, one of its shortcomings is its relatively low efficiency Note 1 mostly due to the inevitable Note 2 recombination of generated radicals (ca. 80%) to form more stable Note 3 molecules (H2O2, H2O, etc),which reduces the effective Note 4 contact radicals and target contaminants. In order to counter these effects and enhance the oxidation performance by US, its combination with other AOP technologies (photocatalysis, Fenton process, ozonation, etc) has been tested in an attempt to show either an additive or a synergistic Note 5 benefit. The hybrid technique of combining ultraviolet (UV) irradiation and US has been found to be beneficial Note 6 […] Currently, information regarding the US/UV process is relatively limited, Note 7 and a similar conjecture of the auxiliary role of photolysis of the ultrasonically generated H2O2 is proposed. There is a need for more detailed information Note 8 concerning the exact role of H2O2 in the treatment reactions and a mechanistic model to describe the US/UV process; these are addressed in this study. |
| Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014 |
Evaluative language structures:
Although+ statement, problem
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Although Ultrasound (US) can achieve the degradation of refractory compounds, one of its shortcomings is its relatively low efficiency, mostly due to the inevitable recombination of generated radicals (ca. 80%) to form more stable molecules (H2O2), H2O etc), 3 which reduces the effective contact between radicals and target contaminants. |
| Adapted from: L. Xu. “Degradation of Refractory Contaminants in Water by Chemical –Free Radicals Generated by Ultrasound and UV Irradiation”, PhD confirmation report, Dept. of Civil and Env. Eng., POLYU, Hong Kong, 2014 |
Despite + positive statement+ problem
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Despite the many benefits, the application of high frequency application systems is still limited. |
| Adapted from J. Liu. “Investigation of Power Conversion and Control Scheme for High Frequency AC Power Distribution System”, PhD confirmation report, Dept. of Elect. Eng., POLYU, Hong Kong (No date). |
Positive sentence+ semicolon+ however, + negative evaluation.
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Filippova and Strobe (2007) build on an entity-grid coherence model and extend it from co-reference to semantic relatedness ; however, the extension from co-reference to semantic relatedness is not very profitable in their research. |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Negative openings
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Few studies, however, have investigated heat transfer characteristics in an inverse diffusion flame. |
| Adapted from: J. Miao. “Combustion, Thermal and Emission Characteristics of gas-fired Inverse Diffusion Flames Burning Mixed LPG/Hydrogen Fuel”, PhD confirmation report, Dept. of Mech. Eng., POLYU, Hong Kong, (No date). |
Other negative openings
There is little evidence that…
Yet, no study has investigated the …
Coherent organisation of information structures:
Inter-paragraph and intra-paragraph coherence
A Literature Review details, evaluates and synthesises several perspectives on multiple themes. The complex and extensive information thus provided can only be processed easily if it is organised in a logical and coherent manner, both within a paragraph (Inter- paragraph coherence) and between paragraphs (intra-paragraph coherence).
Developing an effective and coherent paragraph structure (inter-paragraph coherence)
This is achieved when each paragraph starts with a topic sentence with specific controlling ideas in the sentence and these ideas are then elaborated before the paragraph concludes with a summary sentence. A controlling idea is part of the topic sentence in a paragraph, which is the main focus of the paragraph. It is illustrated in the paragraph and explained in point 3 in the notes that follow the extract.
Developing coherence across the text (Inter-paragraph coherence)
This is achieved through the following strategies:
- Linking ideas across paragraphs (paragraph hooks)
- The use of effective headings and sub headings (clear, concise and specific headings that allow the reader to anticipate the content of the section).
The following extract from a Confirmation Report in Computer Engineering illustrates strategies which help the author to develop an effective organisational structure.
Click on the numbers in superscript (Note 1-6) to see their explanation.
Note: […] indicates sections have been edited due to space constraints.
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2.1.2 A Taxonomical Account Note 1 The task of text summarization can be classified along various dimensions. Note 2 One is the informational coverage, according to which there are extract, a summary of sentences or phrases verbatim from the source document(s), and abstract, a summary containing original sentences via content reformulation or paraphrase, which is sometimes called non-extractive summary Note 3 (Spärck Jones, 2007: 1473). Non-extractive summarization is a typical human reserve and its computerization usually involves deep semantic / logical analysis on the discourse level and the language generation technique. FRUMP (Dejong, 1982) is an early documented non-extractive system, followed by STREAK, PLANDOC (McKeown et al., 1995), SUMMON (McKeown and Radev, 1995), SUMMARIST (Hovy and Lin, 1999), SumUM (Saggion and Lapalme, 2002), the template-filling approach (Paice and Jones, 1993), the cut-and-paste approach (Jing and McKeown, 1999), etc. Note 4 However, the vast majority of implemented systems and models are targeted at extractive summarization, which has enjoyed a long history and is still the main force. Note 5Taking a functional dimension, Note 6 we can divide summaries into indicative, informative and critical types. Indicative summaries […]. |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Inter-paragraph coherence
In order to link ideas between paragraphs, authors use paragraph hooks and transition statements. These strategies are exemplified in the following extract.
Repeated ideas are color coded.
Click on the numbers in superscript to see their explanations.
Note: […] indicates sections have been deleted due to space constraints.
Extract
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Both the global coherence models and local coherence models may only reveal some coherence patterns and address some issues involved in text summarization. As it is assumed that hybrid models can combine the strengths of individual models, many researchers have explored the potentials of such combinations […]. The lexical cohesion methods (see 2.2.2) are capable of capturing sentence relatedness on a word level, and it is possible to integrate lexical cohesion into a global coherence model. Such an attempt is reported by Alonso i Alemany and Fuentes Fort (2003), who build a hybrid model of text summarization that combines rhetorical relations to account for coherence and lexical chains to account for cohesion. Other hybrid models Note 1 seek to build computationally robust algorithms into coherence approaches. One example is Barzilay and Lee’s (2004) […]. Information ordering approaches are discussed in the section that follows Note 2 2.3.4 Information ordering |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Writing statements of transition and overview
The content of a Literature Review can be complex and include multiple themes, making information processing a challenge for the reader. Authors often use the strategy of including metadiscourse – or information about the text itself – in addition to the content. This strategy helps the reader to understand its organisation and recognise important information easily. Here are some examples of metadiscourse from a selection of confirmation reports.
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Extract 1 |
| Adapted from: R. Zhang. “Coherence-Based Text Summarisation”, PhD confirmation report, Dept. of Computing, POLYU, Hong Kong, 2010. |
Explanatory notes:
The phrases in bold are examples of metadiscourse as they inform the reader about the information presented in the section.
Use of “work” and “works” in Literature Reviews
Novice authors often use “work” and “works” inappropriately when writing the Literature Review. “Work” must be used to convey a precise meaning by using more specific words such as “investigation”, “analysis”, “research” or “review”, as “work” is a vague term that does not indicate the type of work carried out. In the plural form, it refers to work in the arts, such as that of an artist, a composer or a musician. The use of “works” to refer to scientific research is inappropriate and “the literature” is a more acceptable option. The following examples illustrate these two points.
- Overuse of “work”
Some authors use “work” to indicate a study (or studies), an investigation, or research in the field. This may not be grammatically wrong, but is not in line with academic conventions which require that words with specific meanings be used. The meaning of “work” is very vague here, and is therefore not the best word choice. Look at the example below.
- Smith’s (2016) work extends the scope of this research method.
This sentence is grammatically correct, but the meaning of “work” is vague. It can be better written as follows:
- Smith’s (2016) investigation extends the scope of this research method.
- Studies conducted by Smith (2016; 2014) have extended the scope of this research method.
- Misuse of “works” in the Literature Review
The word “works” is often used to describe work in the arts, such as that of an artist, a composer or a musician. One example is, “This album contains the early works of the impressionists whose paintings have influenced many artists in history”.
Some novice authors, however, are not clear about the meaning of this word. As a result, they often use it incorrectly when referring to studies that have been conducted in the field.
In Section 2, I survey a massive collection of works, which serve as the background and stepping stones for achieving the goals of this project.
There are three problems with the sentence. The word “works” is incorrectly used, its tone is informal, and it is unnecessarily lengthy. It can be better written as follows:
Section 2 reviews the literature in the field, which serves as the background information for the project.
Activity 1>> 2
Consider the sentences below and identify the errors connected with the use of “work” and “works” by highlighting the error in each one.
Click check to see the answer.
- Errors
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The following paragraphs are from a Confirmation Report in Electronic and Information Engineering. Paragraph A (in italics) presents background information.Sentences in paragraph B are not in sequence. Re-order them to make the paragraph more coherent.
Hint: Paragraph B discusses cellular components.
- Although the ‘Cellular Component’ ontology is directly related to the subcellular localization, we cannot simply use GO terms to annotate the subcellular locations of proteins.
- In fact, for those proteins that are annotated as ‘Subcellular Location Unknown’ in Swiss-Prot, many of them have GO terms also labelled as ‘Cellular Component Unknown’ in the GO database.
- Because of this limitation, it is necessary to make use of the other two ontologies as they are also relevant (although not directly) to the subcellular localization of proteins.
- This is realized through a GO Processor, which consists of two parts: GO vector construction and GO vector post-processing.
- The reason is that the percentage of proteins that have annotation of cellular components in the GO database is less than the percentage of proteins that have subcellular locations annotations in the Swiss-Prot database .
- On the other hand, proteins with subcellular locations clearly annotated in Swiss-Prot may still be marked as ‘Cellular Component Unknown’ in the GO database .
- We have investigated several approaches to extracting subcellular localization information from the GO database.
Adapted from: S. Wan. “Protein Subcellular Localization Prediction Based on Gene Ontology and SVM”, PhD confirmation report, Dept. of Elec. and Inf. Eng., POLYU, Hong Kong, 2011.
Answer Key
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B Although the ‘Cellular Component’ ontology is directly related to the subcellular localization, we cannot simply use GO terms to annotate the subcellular locations of proteins. The reason is that the percentage of proteins that have annotation of cellular components in the GO database is less than the percentage of proteins that have subcellular locations annotations in the Swiss-Prot database. In fact, for those proteins that are annotated as ‘Subcellular Location Unknown’ in Swiss-Prot, many of them have GO terms also labelled as ‘Cellular Component Unknown’ in the GO database. On the other hand, proteins with subcellular locations clearly annotated in Swiss-Prot may still be marked as ‘Cellular Component Unknown’ in the GO database. Because of this limitation, it is necessary to make use of the other two ontologies as they are also relevant (although not directly) to the subcellular localization of proteins. We have investigated several approaches to extracting subcellular localization consists of two parts: GO vector construction and GO vector post-processing. This is realized through a GO Processor, which consists of two parts: GO vector construction and GO vector post-processing. |
Answer Key: d, b, f, e, c, a, g.
Explanation for the organisation of information:
- The linking expression ‘Although’ in ‘d’ concedes a point about ‘Cellular Component ontology’, an idea that is stated in Paragraph A (In the GO database, the annotations of gene products are organized in three related ontologies: cellular components…). ‘Cellular component ontology’ is therefore a paragraph hook ‘d’ should be the first sentence in paragraph B.
- ‘b’ follows on from ‘d’, as it provides a reason for why ‘we cannot simply use GO terms to annotate the subcellular locations of proteins’.
- ‘f’ illustrates the reason (b) with an example using ‘in fact’ and follows sentence ‘b’.
- ‘e’ provides information that contrasts with that provided in ‘f’ (on the other hand). In ‘f’, we know that for ‘proteins annotated as ‘Subcellular Location Unknown’ in Swiss-Prot, many of them have GO terms also labelled as ‘Cellular Component Unknown’ in the GO database’. In ‘e’, we are informed that, in contrast, proteins with subcellular locations clearly annotated in Swiss-Prot may still be marked as ‘Cellular Component Unknown’ in the GO database.
- ‘c’ refers to a ‘limitation’ – that outlined in ‘e’ and thus follows sentence ‘e’.
- ‘a’ outlines the writer’s efforts to extract ‘subcellular localization information from the GO database’.
- ‘g’ explains how their effort was realised, and hence follows ‘a’.
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