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    Design of environmental performance measurement systems for agriculture

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    University of Technology Sydney. Faculty of Business.The research question addressed in this thesis is: how can Environmental Performance Measurement Systems (EPMS) be designed and used in an agricultural setting to support managers in water and economic sustainability-related decision making and control. Sustainability and the increasing scarcity of natural resources such as freshwater are of growing social interest. Agriculture has a significant impact on the sustainability of freshwater at both global and local levels. As agriculture is economically and socially significant in meeting human needs for food and clothing, it is surprising that there has been very little management accounting research conducted within an agricultural setting and almost none on its role in environmental sustainability. Extant EPMS research manifests two underlying theoretical problems, which are also reflected in broader performance measurement systems research. First, the research provides little insight into how to design valid environmental performance measures which could provide managers with precise information to enable decision making and control over environmental sustainability. I argue that there are two key reasons for this: that theories from natural science are yet to inform EPMS design; and that while environmental management typically occurs at an operational level, EPMS typically reside at the organisational level. The second theoretical problem is the lack of existing research that considers how environmental performance standards can be developed for use as targets to support managers in improving sustainability-related decision making and control. I address these two problems with a new theoretical construction of a multi-level decomposition EPMS model - which I label, Water and Economic Sustainability Performance Measurement (WESM). The model integrates science into an accounting framework. This design overcomes the two key challenges with EPMS validity. I subsequently examine how the WESM model can be used to support managers in improving sustainability-related decision making and control using a two- phased crop production simulation modelling approach. The simulation results provide significant implications for the cotton industry (and agriculture more broadly) with the potential to save hundreds of gigalitres of water and increase profitability by tens of millions of dollars per crop season for cotton farming in Australia. The research also makes a theoretical contribution to the accounting literature by developing and applying theory from science to overcome inherent validity and target setting problems in PMS design. In addition, I demonstrate the usefulness of simulation modelling as a research method, which has yet to have a great deal of application in accounting research designs beyond few costing studies

    UHPLC-QTOF/MS๋ฅผ ํ™œ์šฉํ•œ building block ์ „๋žต ๋ฐ ์ด๋ฅผ ํ™œ์šฉํ•œ Gymnema ๋ฐ Gynostemma ์† triterpenoids ๋Œ€์‚ฌ์ฒด ํ”„๋กœํŒŒ์ผ๋ง ์—ฐ๊ตฌ

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    ํ•™์œ„๋…ผ๋ฌธ(๋ฐ•์‚ฌ)--์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› :์•ฝํ•™๋Œ€ํ•™ ์•ฝํ•™๊ณผ,2019. 8. Oh, Won Keun.๊ตญ๋ฌธ์ดˆ๋ก Part 1. Gymnema sylvestre๋Š” ์ „ํ†ต์ ์œผ๋กœ ์•„์œ ๋ฅด๋ฒ ๋‹ค ์˜ํ•™์—์„œ ๋‹น๋‡จ์น˜๋ฃŒ์— ์‚ฌ์šฉ๋˜์–ด์™”๋‹ค. ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋ฒ ํŠธ๋‚จ๊ณผ ์ธ๋„์˜ Gymnema sylvestre์„ ํ˜•ํƒœํ•™์ ์œผ๋กœ ๊ตฌ๋ถ„ํ•˜์˜€๊ณ  ๋ฒ ํŠธ๋‚จ์˜ Gymnema sylvestre์—์„œ ๋ถ„๋ฆฌํ•œ 6๊ฐœ์˜ ์‹ ๊ทœํ™”ํ•ฉ๋ฌผ (1-6)์˜ ์กฐ๊ฐ์ด์˜จ ํŒจํ„ด์„ ํ™”ํ•™์„ฑ๋ถ„ ๋ถ„์„์— ํ™œ์šฉํ•˜์˜€๋‹ค. ๋ณธ ์‹๋ฌผ์˜ ๋ถ„๋ฆฌ ๋ฐ ๋™์ •์„ ํ†ตํ•˜์—ฌ ์ด๋ฏธ ์•Œ๊ณ  ์žˆ๋Š” ์กฐ๊ฐ์ด์˜จ์˜ ํŒจํ„ด๊ณผ ์ด ์‹๋ฌผ์˜ oleanane triterpenoid ์˜ ์ƒํ•ฉ์„ฑ ๊ณผ์ •์„ ํ† ๋Œ€๋กœ building block ์ „๋žต์„ ํ™œ์šฉํ•˜์—ฌ ๊ฐ๊ฐ์˜ ํ”ผํฌ๋ฅผ ๋™์ •ํ•˜์˜€๋‹ค. ์ด ๊ณผ์ •์—์„œ ์†Œ๋ถ„ํš, mass ์กฐ๊ฐ์ด์˜จ ํŒจํ„ด, relative mass defect filtering, reference์™€ ๋น„๊ต ๋“ฑ์˜ ๋ฐฉ๋ฒ•์ด ์ ์šฉ๋˜์—ˆ๋‹ค. ์ด 119๊ฐœ์˜ ํ”ผํฌ๊ฐ€ oleanane triterpenoid ๊ณ„์—ด๋กœ ๋ถ„๋ฅ˜๋˜์—ˆ์œผ๋ฉฐ ๊ทธ ์ค‘ 77๊ฐœ์˜ ํ”ผํฌ๊ฐ€ ์‹ ๊ทœํ™”ํ•ฉ๋ฌผ์ž„์„ ํ™•์ธํ•˜์˜€๋‹ค. Part 2. ์ฒœ์—ฐ๋ฌผ์€ PTP1B์–ต์ œ๋ฅผ ํ†ตํ•œ ํ•ญ๋‹น๋‡จ ํšจ๊ณผ ํ›„๋ณด๋ฌผ์งˆ์˜ ํ›Œ๋ฅญํ•œ ์›์ฒœ์ด๋ฉฐ ์ด์— ๋”ฐ๋ผ ์„ ๋ณ„๋œ Korea Bioactive Natural Material Bank์˜ ์‹๋ฌผ์ถ”์ถœ๋ฌผ๋“ค์— ๋Œ€ํ•œ ์Šคํฌ๋ฆฌ๋‹ ์ž‘์—…์„ ์‹ค์‹œํ•˜์˜€์œผ๋ฉฐ ๊ทธ ๊ฒฐ๊ณผ Gymnema latifolium 70% ์—ํƒ„์˜ฌ ์ถ”์ถœ๋ฌผ์ด PTP1B ์–ต์ œ ํšจ๋Šฅ์„ ๋ณด์˜€๋‹ค. ์ด๋Š” ํ˜„์žฌ ๋ฒ ํŠธ๋‚จ์—์„œ ํ•ญ๋‹น๋‡จ ์น˜๋ฃŒ์ œ๋กœ Gymnema latifolium์ด ํ™œ์šฉ๋˜๊ณ  ์žˆ๋Š” ๊ฒฐ๊ณผ์™€๋„ ์ผ์น˜ํ•˜์˜€๋‹ค. ์ด์— ๋ณธ ์—ฐ๊ตฌ๋Š” 14์ข…์˜ ์‹ ๊ทœ oleanane triterpene์ธ Gymlatinosides (1-14)์™€ 6๊ฐœ์˜ ๊ธฐ์ง€๋ฌผ์งˆ์„ ๋ถ„๋ฆฌ ๋™์ •ํ•˜์˜€๋‹ค. Gymlatinoside GL2์™€ GL3๋Š” ์ƒ๋ฆฌํ™œ์„ฑ ๊ฒฐ๊ณผ ๊ฐ๊ฐ IC50 ๊ฐ’ 28.66ยฑ2.57 ๊ณผ 19.83ยฑ0.40์„ ๋‚˜ํƒ€๋‚ด์–ด PTP1B๋ฅผ ์œ ์˜๋ฏธํ•˜๊ฒŒ ์–ต์ œํ•˜์˜€์Œ์„ ํ™•์ธํ•˜์˜€๋‹ค. ๋˜ํ•œ building block ์ „๋žต์„ ์ด์šฉํ•˜์—ฌ 54๊ฐœ์˜ ์‹ ๊ทœ ํ”ผํฌ๋ฅผ ์ถ”์ •ํ•˜์˜€๋‹ค. Part 3. Gynostemma longipes ์—์„œ๋Š” 8์ข…์˜ ์‹ ๊ทœ 12,23-dione dammarane triterpenoid์™€ 1์ข…์˜ gypetonoside๊ฐ€ ๋ถ„๋ฆฌ๋˜์—ˆ์œผ๋ฉฐ building block ์ „๋žต์„ ์ด์šฉํ•˜์—ฌ 32๊ฐœ์˜ ํ”ผํฌ๊ฐ€ ์‹ ๊ทœ๋ฌผ์งˆ๋กœ ์ถ”์ •๋จ์„ ํ™•์ธํ•˜์˜€๋‹ค. ๋ถ„๋ฆฌํ•œ 9์ข…์˜ ํ™”ํ•ฉ๋ฌผ์— ๋Œ€ํ•ด์„œ๋Š” AMPK ํ™œ์„ฑ์„ ๊ฒ€์‚ฌํ•˜์˜€์œผ๋ฉฐ C2C12 ๊ทผ์œก์„ธํฌ์— 7์ข…์˜ ํ™”ํ•ฉ๋ฌผ (1, 3-8)์„ ์ฒ˜์น˜ํ•˜์˜€์„ ๊ฒฝ์šฐ AMPK ํ™œ์„ฑ์„ ์ฆ๊ฐ€์‹œํ‚ค๋Š” ๊ฒƒ์œผ๋กœ ํ™•์ธํ•˜์˜€๋‹ค. ํ™”ํ•ฉ๋ฌผ 1์˜ ๊ฒฝ์šฐ ์‹๋ฌผ ๊ฑด์กฐ๋Ÿ‰ ๋Œ€๋น„ 2.08%์˜ ํ•จ๋Ÿ‰์„ ๊ฐ€์ง€๋Š” ๊ฒƒ์œผ๋กœ ํ‰๊ฐ€๋˜์–ด ํ–ฅํ›„ ๊ธฐ๋Šฅ์„ฑ์‹ํ’ˆ์œผ๋กœ์˜ ๋ฐœ์ „ ๊ฐ€๋Šฅ์„ฑ์„ ์ œ์‹œํ•˜์˜€๋‹ค. ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” Gynostemma longipes์˜ AMPK ํ™œ์„ฑ์„ ํ†ตํ•œ ๊ทผ์œก์„ธํฌ ์ฆ์‹์„ ํ™•์ธํ•˜์˜€๋‹ค.The quality control of a medicinal plant requires a rapid, accurate, and comprehensive analysis of the chemical profile of the bioactive extract. Common HRMS-based compound annotations relied on the mass fragmentation analysis of detected peaks to identify the partial structure of the compounds before merging them together. Herein, we applied a universally accepted concept that most of the natural products of the same organic origin are generated by the same building blocks using several conservative biosynthetic processes. The detection of metabolites - both known and unknown - can be redefined by an inverse approach, in which, prebuilt natural products were predicted using key prefabricated LEGO-type building blocks and their biosynthetic construction rules. The conventional mass fragmentation pattern analysis and NMR experiments are for the confirmation of the existence of predicted compounds. Furthermore, we proposed a new idea of multilayer metabolite profiling, which provides simple, distinct, and comprehensive chromatogram interface with not only original information about retention time of metabolites, but also considerable insight into structure formation as well as the chemical relationship among plant metabolites. In this study, the building block strategy was applied effectively to explore the triterpenoid composition of three medicinal plants including Gymnema sylvestre, Gymnema latifolium and Gynostemma longipes. Overall, we expect this new approach can be used, with much practicality, for massive structural characterization and for exploring the biosynthetic relationships among various compounds in medicinal plants. Part 1: Discrimination of different geographic varieties of Gymnema sylvestre and development of a building block strategy to classification, identification and metabolite profiling of its oleanane triterpenoids The major class of bioactive metabolites in Gymnema sylvestre, a popular Ayurevedic medicinal plant for the treatment of diabetes mellitus, is oleanane triterpenoids. In this study, a targeted, biosynthesis-inspired approach using UHPLC-qTOF/MS was implemented to elucidate the whole chemical profile of the plant for the standardization of the Vietnamese G. sylvestre variety. The known compounds reported in the literature were first analyzed to identify the building blocks of the biosynthetic intermediates and the construction rules for synthesizing oleanane triterpenoids in the plant. These blocks were recombined to build up a theoretical virtual library of all reasonable compounds consistent with the deduced construction rules. Various techniques, including microfractionation, relative mass defect filtering, multiple key ion analysis, mass fragmentation analysis, and comparison with standard references, were applied to determine the presence of these predicted compounds. Conventional isolation and structure elucidation of 6 of the new compounds were carried out to identify new building blocks and validate the assignments. Consequently, 119 peaks were quickly assigned to oleanane triterpenoid, and among them, 77 peaks are predicted to be new compounds based on their molecular formulas and mass fragmentation patterns. All the identified metabolites were then classified into different layers to analyze their logical relationships and construct a multilayered chemical profile of the oleanane triterpenoids. Part 2: Oleanane triterpenoids from Gymnema latifolium and their PTP1B inhibitory activities Natural products are promising sources of lead compounds that play significant roles in the discovery of new antidiabetic agents via the mechanism of PTP1B inhibition. In our ongoing research to find PTP1B inhibitors from natural products, hundreds of plants extracts available in Korea Bioactive Natural Material Bank has been screened against this biological target. An extract of the Gymnema latifolium Wall. ex. Wight showed considerable PTP1B inhibitory activity. This result was in good agreement with the use of this plant in Vietnam as an antidiabetic herbal medicine, similar with its taxonomical relative G. sylvestre. It is also well-known that most species belonging to the same genus possess similar chemical composition and thus exhibit similar biological activities. Further chemical investigation of this plant led to the isolation of 14 new oleanane triterpenes Gymlatinosides GL1-GL14 and 6 known oleanolic acid analogs. The structures of the new compounds were elucidated using diverse spectroscopic methods. Among them, compounds Gymlatinosides GL2 and GL3 showed significant PTP1b inhibitory effect. The building block strategy was also applied successfully to predict the structures of 54 new compounds which may have similar skeleton and biosynthesis construction with those isolates. Part 3: 12,23-Dione dammarane triterpenes from Gynostemma longipes and their muscle cell proliferation activities via activation of the AMPK pathway. The aging population is growing rapidly around the world. Sarcopenia, characterized by decreased muscle mass, strength, and function, is a common feature of the elderly population. AMP-activated protein kinase (AMPK) is an essential sensor and regulator of glucose, lipid, and energy metabolism throughout the body. Previous studies have shown that AMPK pathway activation by regular exercise and appropriate dietary control have beneficial effects on skeletal muscle. In the process of searching for new AMPK activators from medicinal plants, we isolated and characterized eight new 12,23-dione dammarane triterpenoids (1โ€“3 and 5โ€“9), as well as one known gypentonoside A from Gynostemma longipes. Application of the building blocks and their construction rules also led to the assignment of 26 possible new compounds. All 9 isolated compounds were tested for their AMPK activation activities, seven compounds (1 and 3โ€“8) were significantly activated AMPK phosphorylation in mouse C2C12 skeletal muscle cell lines. Since G. longipes contained a significant amount of active compound Longipenoside A1 (over 2.08% per dried raw plant), it suggested the potential of this plant to be developed as a functional food or botanical drug that enhances muscle proliferation by activating AMPK signaling pathways.1. Introduction 1 Purpose of research 5 2. Materials and methods 7 2.1. Plant materials 7 2.2. Morphology and anatomy analysis 7 2.3. ITS1-5.8S-ITS2 sequence analysis 7 2.3. Establishment of a Virtual Mass Library based on Building Blocks 8 2.4. UPLC-ESI-MSn Experiments 9 2.5. Hydrolysis of Total Extract 10 2.6. Extraction and isolation schemes 11 2.6.1. General experimental procedures 11 2.6.2. Isolation scheme 12 2.6.3. Physical and chemical characteristics of isolated compounds 14 3. Results and discussion 16 3.1. Discrimination of different geographic varieties of G. sylvestre 16 3.1.1. Agronomical characteristics 16 3.1.2. Morphological and anatomical characteristics 16 3.1.3. Internal transcribed spacer ITS1-5.8S-ITS2 sequence analysis 21 3.2. Development of a building block strategy to classification, identification and metabolite profiling of oleanane triterpenoids in the Vietnamese G. sylvestre variety using UHPLC-qTOF/MS 23 3.2.1. Building Blocks and Construction Rules of Triterpenoids isolated from G. Sylvestre. 23 3.2.2. Relative mass filtering 28 3.2.3. Identification of Targeted Metabolites by UPLC-MSn. 29 3.3. Structure elucidation of selective isolation of new compounds predicted by virtual block library 45 3.3.1. Gymnemoside GS1 - Compound 1 50 3.3.1. Gymnemoside GS2 - Compound 2 53 3.3.3. Gymnemoside GS3 - Compound 3 54 3.3.4. Gymnemoside GS4 - Compound 4 56 3.3.5. Gymnemoside GS5 โ€“ Compound 5 57 3.3.6. Gymnemoside GS6 - Compound 6 58 3.4. Metabolite Profiling of Oleanane Triterpenoids 59 4. Conclusions 61 Part 2. Oleanane triterpenoids from Gymnema latifolium and their PTP1B inhibitory activities 62 1. Introduction 62 Purpose of research 64 2. Materials and methods 65 2.1. Plant materials 65 2.2. Extraction and isolation schemes 65 2.2.1. General experimental procedures 65 2.2.2. Isolation scheme 66 2.2.3. Physical and chemical characteristics of isolated compounds 70 2.3. Acid Hydrolysis 72 2.4. PTP1B Assay 73 3. Results and discussion 75 3.1. Authentication of Gymnema latifolium Wall ex. Wight 75 3.2. Oleanane triterpenoids isolated from G. latifolium 78 3.2.1. Gymlatinoside GL1 (1) 82 3.2.2. Gymlatinoside GL2 (2) 86 3.2.3. Gymlatinoside GL3 (3) 87 3.2.4. Gymlatinoside GL4 (4) 88 3.2.5. Gymlatinoside GL5 (5) 89 3.2.6. Gymlatinoside GL6 (6) 90 3.2.7. Gymlatinoside GL7 (7) 91 3.2.8. Gymlatinoside GL8 (12) 97 3.2.9. Gymlatinoside GL9 (13) 99 3.2.10. Gymlatinoside GL10 (14) 100 3.2.11. Gymlatinoside GL11 (15) 101 3.2.12. Gymlatinoside GL12 (16) 102 3.2.13. Gymlatinoside GL13 (17) 104 3.2.14. Gymlatinoside GL14 (18) 105 3.3. PTP1B inhibitory activities of isolated compounds 106 3.4. Building block assignments for oleanane glycosides in G. latifolium 106 3.4.1. 3-ฮฒ-hydroxy oleanane glycosides 106 3.4.2. 23-hydroxy oleanane glycosides 111 4. Conclusions 113 Part 3: 12, 23-Dione dammarane triterpenoids from Gynostemma longipes and their muscle cell proliferation activities via activation of the AMPK pathway. 114 1. Introduction 114 Purpose of research 116 2. Materials and methods 117 2.1. Plant materials 117 2.2. Isolation and structure elucidation of compounds 119 2.2.1. General experimental procedures 119 2.2.2. Isolation scheme 120 2.2.3. Physical and chemical characteristics of isolated compounds 121 2.2.4. Acid hydrolysis 123 2.2.5. Quantitative analysis of Longipenoside A1 (compound 1) 123 2.3. Muscle regeneration activity of G. longipes extract and isolated compounds 124 2.3.1. Cell proliferation assay 124 2.3.2. Western blot analysis 125 2.3.3. Immunochemical staining with BrdU antibody 126 2.3.4. Flow cytometry analysis for BrdU and PI staining 127 2.3.5. Flow cytometry of cell cycle status 127 2.3.6. Glucose uptake assay 128 2.3.7. Measurement of ATP level 128 2.3.8. Statistical analysis 129 3. Results and discussion 130 3.1. Structural determination of new compounds 130 3.1.1. Longipenoside A1 (1) 134 3.1.2. Longipenoside A2 (2) 137 3.1.3. Longipenoside A3 (3) 138 3.1.4. Longipenoside A4 (5) 139 3.1.5. Longipengenol (6) 140 3.1.6. 3-dehydro longipengenol (7) 141 3.1.7. Longipenoside A5 (8) 142 3.1.7. Longipenoside A6 (9) 143 3.2. Annotations of dammarane triterpenoids in G. latifolium using building block strategy 144 3.3. Dammarane triterpenes enhanced muscle proliferation through activating AMPK 146 3.4. Effects of dammarane triterpenes on DNA synthesis during cell proliferation. 152 3.5. Effects of dammarane triterpenes on glucose uptake and ATP levels 155 3.6. Enhancement of cell proliferation by dammarane triterpenes through cell cycle regulation 156 4. Conclusion 158 References 160Docto

    Cash holding, state ownership and firm value: The case of Vietnam

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    Using a sample of 650 listed firms on the Vietnamese stock exchange over the period 2008-2015, we examine the effect of cash holding level on firm value. The results find out the cash holding has an impact on firm value in an inverted U-shaped form. Furthermore, this study investigates whether the state ownership influences firm value. We point out that there is a statistically insignificant positive relationship between state ownership and firm value unless the state ownershipโ€™s advantages are utilized. The findings have implications of cash management in state-owned firms. ยฉ 2016, Econjournals. All rights reserved

    Nonparametric estimation of the fragmentation kernel based on a PDE stationary distribution approximation

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    We consider a stochastic individual-based model in continuous time to describe a size-structured population for cell divisions. This model is motivated by the detection of cellular aging in biology. We address here the problem of nonparametric estimation of the kernel ruling the divisions based on the eigenvalue problem related to the asymptotic behavior in large population. This inverse problem involves a multiplicative deconvolution operator. Using Fourier technics we derive a nonparametric estimator whose consistency is studied. The main difficulty comes from the non-standard equations connecting the Fourier transforms of the kernel and the parameters of the model. A numerical study is carried out and we pay special attention to the derivation of bandwidths by using resampling

    Teaching experiments in constructing mathematical problems that st relate to real life

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    EVALUATION OF SOLAR RADIATION ESTIMATED FROM HIMAWARI-8 SATELLITE OVER VIETNAM REGION

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    The development of Solar energy system is growing rapidly in Vietnam in recent years by encouragement of the Government in renewable energy. Requirement for accurate knowledge of the solar radiation reaching the surface is increasingly important in the successful deployment of Solar photovoltaic plants. However, measurements of different components of solar resources including direct normal irradiance (DNI) and global horizontal irradiance (GHI) are limited to few stations over whole country. Satellite imagery provides an ability to monitor the surface radiation over large areas at high spatial and temporal resolution as alternatives at low cost. Observations from the new Japanese geostationary satellite Himawari-8 produce imagery covering Asia-Pacific region, permitting estimation of GHI and DNI over Vietnam at 10-minute temporal resolution. However, accurate comparisons with ground observations are essential to assess their uncertainty. In this study, we evaluated the Himawari-8 radiation product AMATERASS provided by JST/CREST TEEDDA using observations recorded at 5 stations in different regions of Vietnam. The result shows good agreement between satellite estimation and observed data with high correlation of range 0.92-0.94, but better in clear-sky episodes.Because of AMATERASS outperform, we used it for validating ERA-Interim reanalysis in the spatial scale. The comparison was made dividedly for 7 climate zones and 4 seasons. The conclusion is that ERA-Interim is also well associated with satellite-based estimates in seasonal trend for all season, but in average the reanalysis has negative bias towards satellite estimates. This underestimation is more pronounced in the months of JJA and SON periods and in the north part of Vietnam because of unpredicted cloud in the ERA reanalysis

    DEVELOPMENT AND APPLICATION OF THE ENVIRONMENTAL HYDRODYNAMIC 3D MODEL FOR COMPUTATION AND FORECASTING OF OIL POLLUTIONS IN COASTAL MARINE ENVIRONMENT

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    Joint Research on Environmental Science and Technology for the Eart

    COLOR AND COD REMOVAL OF DYEING WASTEWATER BY COMBINATION TREATMENT OF COAGULATION AND FENTON OXIDATION

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    Joint Research on Environmental Science and Technology for the Eart

    Improving Zero-shot Translation with Language-Independent Constraints

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    An important concern in training multilingual neural machine translation (NMT) is to translate between language pairs unseen during training, i.e zero-shot translation. Improving this ability kills two birds with one stone by providing an alternative to pivot translation which also allows us to better understand how the model captures information between languages. In this work, we carried out an investigation on this capability of the multilingual NMT models. First, we intentionally create an encoder architecture which is independent with respect to the source language. Such experiments shed light on the ability of NMT encoders to learn multilingual representations, in general. Based on such proof of concept, we were able to design regularization methods into the standard Transformer model, so that the whole architecture becomes more robust in zero-shot conditions. We investigated the behaviour of such models on the standard IWSLT 2017 multilingual dataset. We achieved an average improvement of 2.23 BLEU points across 12 language pairs compared to the zero-shot performance of a state-of-the-art multilingual system. Additionally, we carry out further experiments in which the effect is confirmed even for language pairs with multiple intermediate pivots.Comment: 10 pages version accepted in WMT 201
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