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An Improved Hybrid Deep Learning Approach for Security Requirements Classification
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作者 Shoaib Hassan QianmuLi +2 位作者 Muhammad Zubair Rakan AAlsowail Muhammad Umair 《Computers, Materials & Continua》 2025年第3期4041-4067,共27页
As the trend to use the latestmachine learning models to automate requirements engineering processes continues,security requirements classification is tuning into the most researched field in the software engineering ... As the trend to use the latestmachine learning models to automate requirements engineering processes continues,security requirements classification is tuning into the most researched field in the software engineering community.Previous literature studies have proposed numerousmodels for the classification of security requirements.However,adopting those models is constrained due to the lack of essential datasets permitting the repetition and generalization of studies employing more advanced machine learning algorithms.Moreover,most of the researchers focus only on the classification of requirements with security keywords.They did not consider other nonfunctional requirements(NFR)directly or indirectly related to security.This has been identified as a significant research gap in security requirements engineering.The major objective of this study is to propose a security requirements classification model that categorizes security and other relevant security requirements.We use PROMISE_exp and DOSSPRE,the two most commonly used datasets in the software engineering community.The proposed methodology consists of two steps.In the first step,we analyze all the nonfunctional requirements and their relation with security requirements.We found 10 NFRs that have a strong relationship with security requirements.In the second step,we categorize those NFRs in the security requirements category.Our proposedmethodology is a hybridmodel based on the ConvolutionalNeural Network(CNN)and Extreme Gradient Boosting(XGBoost)models.Moreover,we evaluate the model by updating the requirement type column with a binary classification column in the dataset to classify the requirements into security and non-security categories.The performance is evaluated using four metrics:recall,precision,accuracy,and F1 Score with 20 and 28 epochs number and batch size of 32 for PROMISE_exp and DOSSPRE datasets and achieved 87.3%and 85.3%accuracy,respectively.The proposed study shows an enhancement in metrics values compared to the previous literature studies.This is a proof of concept for systematizing the evaluation of security recognition in software systems during the early phases of software development. 展开更多
关键词 requirements engineering security requirements deep learning CNN XGBoost CLASSIFICATION
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Exporting Perfumes to China:Key Compliance and Import Requirements
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作者 Jarius Ji 《China Detergent & Cosmetics》 2025年第2期12-15,共4页
China's perfume market has been experiencing significant growth.The “2024 China Perfume and Fragrance White Paper”,jointly published by Eternal Group,DSM-Firmenich,and Ipsos in September 2024,reveals that the ma... China's perfume market has been experiencing significant growth.The “2024 China Perfume and Fragrance White Paper”,jointly published by Eternal Group,DSM-Firmenich,and Ipsos in September 2024,reveals that the market surged from 11.4 billion yuan in 2018 to 22.9 billion yuan in 2023,achieving a compound annual growth rate(CAGR) of 15%.With projections estimating a rise to 44 billion yuan by 2028 at a 14% CAGR,the sector's long-term growth prospects remain strong. 展开更多
关键词 growth prospects white paper China COMPLIANCE perfumes perfume market import requirements
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Large Language Models in Software Engineering Education: A Preliminary Study on Software Requirements Engineering Courses
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作者 Feng Chen Shaomin Zhu +1 位作者 Xin Liu Ying Qian 《计算机教育》 2025年第3期24-33,共10页
The advent of large language models(LLMs)has made knowledge acquisition and content creation increasingly easier and cheaper,which in turn redefines learning and urges transformation in software engineering education.... The advent of large language models(LLMs)has made knowledge acquisition and content creation increasingly easier and cheaper,which in turn redefines learning and urges transformation in software engineering education.To do so,there is a need to understand the impact of LLMs on software engineering education.In this paper,we conducted a preliminary case study on three software requirements engineering classes where students are allowed to use LLMs to assist in their projects.Based on the students’experience,performance,and feedback from a survey conducted at the end of the courses,we characterized the challenges and benefits of applying LLMs in software engineering education.This research contributes to the ongoing discourse on the integration of LLMs in education,emphasizing both their prominent potential and the need for balanced,mindful usage. 展开更多
关键词 Large language models Software engineering Software requirements engineering EDUCATION
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Communications in Urban Low-Altitude Drone Logistics Networks:Requirements,Solutions and Challenges
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作者 Duan Ruiyang Mao Yinian +1 位作者 Chen Jialong Song Jian 《China Communications》 2025年第9期37-47,共11页
Communications system has a signifi-cant impact on both operational safety and logisti-cal efficiency within low-altitude drone logistics net-works.Aiming at providing a systematic investiga-tion of real-world communi... Communications system has a signifi-cant impact on both operational safety and logisti-cal efficiency within low-altitude drone logistics net-works.Aiming at providing a systematic investiga-tion of real-world communication requirements and challenges encountered in Meituan UAV’s daily oper-ations,this article first introduces the operational sce-narios within current drone logistics networks and an-alyzes the related communication requirements.Then,the current communication solution and its inherent bottlenecks are elaborated.Finally,this paper explores emerging technologies and examines their application prospects in drone logistics networks. 展开更多
关键词 communication challenges communication requirements drone logistics low-altitude economy
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Beamforming Design for Transmissive RISs-Aided Indoor Communications Under Different Service Requirements
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作者 Pang Lihua Wang Yue +3 位作者 Zhang Yang Zhang Yiteng Chen Yijian Wang Anyi 《China Communications》 2025年第8期58-75,共18页
As emerging services continue to be explored,indoor communications geared towards different user requirements will face severe challenges such as larger penetration losses and more critical multipath issues,leading to... As emerging services continue to be explored,indoor communications geared towards different user requirements will face severe challenges such as larger penetration losses and more critical multipath issues,leading to difficulties in achieving flexible coverage.In this paper,we introduce transmissive reconfigurable intelligent surfaces(RISs)as intelligent passive auxiliary devices into indoor scenes,replacing conventional ultra-dense small cell and relay forwarding approaches to address these issues at low deployment and operation costs.Specifically,we study the optimization design of active and passive beamforming for the transmissive RISs-aided indoor multiuser downlink communication systems.This involves considering more realistic indoor congestion modeling and near-field propagation characteristics.The goal of our optimization is to minimize the total transmit power at the access point(AP)for different user service requirements,including quality-of-service(QoS)and wireless power transfer(WPT).Due to the nonconvex nature of the optimization problem,adaptive penalty coefficients are imported to solve it alternatively with closed-form solutions for both active and passive beamforming.Simulation results demonstrate that the use of transmissive RISs is indeed an efficient way to achieve flexible coverage in indoor scenarios.Furthermore,the proposed optimization algorithm has been proven to be effective and robust in achieving energy-saving transmission. 展开更多
关键词 active and passive beamforming different user requirements indoor communications NEAR-FIELD transmissive reconfigurable intelligent surface(RIS)
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Specifying Requirements of Real-Time System with Rules and Templates 被引量:8
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作者 Wu Guo-qing Xiao Hai-feng +1 位作者 Zheng Pen Ying Shi 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第3期278-284,共7页
This paper presents a model specifying requirements of real-time systems. Different from existing researches, this model mainly uses rules and templates to represent hierarchical FSMs (Finite State Machine). In this m... This paper presents a model specifying requirements of real-time systems. Different from existing researches, this model mainly uses rules and templates to represent hierarchical FSMs (Finite State Machine). In this model, one rule corresponds to one state transition of FSM and one template corresponds to one FSM. Rules and information with respect to a FSM can be written in a template. So templates include not only state diagrams, but also information that can not be described by FSM, such as performance requirements. The specification using this model consists of a collection of templates and it is easy for users to understand and to review. After introduced the related researches and principles of the model, this paper specifies requirements of a real-time system with this model, and discusses characters of this model in the end. 展开更多
关键词 requirements specification model requirements specification real-time system finite state machine
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Macromineral requirements of Dorper×thin-tailed Han crossbred female lambs 被引量:1
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作者 JI Shou-kun XU Gui-shan +4 位作者 DIAO Qi-yu DENG Kai-dong JIANG Cheng-gang TU Yan ZHANG Nai-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第8期1617-1626,共10页
A comparative slaughter trial was conducted to determine the net mineral requirements for maintenance and growth of Dorper crossbred female lambs raised from 20 to 35 kg of body weight(BW).Thirty-five Dorper×th... A comparative slaughter trial was conducted to determine the net mineral requirements for maintenance and growth of Dorper crossbred female lambs raised from 20 to 35 kg of body weight(BW).Thirty-five Dorper×thin-tailed Han crossbred female lambs of(20.3±1.14) kg BW were used: 7 lambs were randomly chosen and slaughtered at the beginning of the experiment as the baseline group for measuring the initial body composition; another 7 lambs were randomly chosen and offered a pelleted mixed diet ad libitum and slaughtered at(27.0±0.73) kg BW; the remaining 21 lambs were randomly divided into 3 groups of 7 animals each and subjected to the same diet either ad l ibitum or at 70 or 40% of ad libitum intake.The 21 lambs were fed in 7 slaughter groups, with each group consisting of one lamb from each treatment(ad libitum, 70 or 40% of ad libitum intake).The 3 groups were slaughtered when the sheep fed ad libitum attained(33.8±0.52) kg of BW.The body composition of five minerals(Ca, P, Na, K, and Mg) was determined.The net mineral requirements for maintenance were 35.01, 25.18, 9.30, 31.35, and 2.03 mg kg–1 empty BW(EBW) for Ca, P, Na, K, and Mg, respectively, and the net growth requirement per kg of EBW gain ranged from 9.73 to 8.87 g of Ca, 5.83 to 5.27 g of P, 1.73 to 1.63 g of Na, 3.73 to 4.08 g of K, and 0.26 to 0.25 g of Mg for Dorper crossbred lambs in China, respectively.The estimates of mineral requirements with Dorper crossbred lambs in the current study were not consistent with the recommendations from previous studies. 展开更多
关键词 macrominerals comparative slaughter trials maintenance requirements growth requirements SHEEP
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Automated Test Case Generation from Requirements: A Systematic Literature Review 被引量:1
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作者 Ahmad Mustafa Wan M.N.Wan-Kadir +5 位作者 Noraini Ibrahim Muhammad Arif Shah Muhammad Younas Atif Khan Mahdi Zareei Faisal Alanazi 《Computers, Materials & Continua》 SCIE EI 2021年第5期1819-1833,共15页
Software testing is an important and cost intensive activity in software development.The major contribution in cost is due to test case generations.Requirement-based testing is an approach in which test cases are deri... Software testing is an important and cost intensive activity in software development.The major contribution in cost is due to test case generations.Requirement-based testing is an approach in which test cases are derivative from requirements without considering the implementation’s internal structure.Requirement-based testing includes functional and nonfunctional requirements.The objective of this study is to explore the approaches that generate test cases from requirements.A systematic literature review based on two research questions and extensive quality assessment criteria includes studies.The study identies 30 primary studies from 410 studies spanned from 2000 to 2018.The review’s nding shows that 53%of journal papers,42%of conference papers,and 5%of book chapters’address requirementsbased testing.Most of the studies use UML,activity,and use case diagrams for test case generation from requirements.One of the signicant lessons learned is that most software testing errors are traced back to errors in natural language requirements.A substantial amount of work focuses on UML diagrams for test case generations,which cannot capture all the system’s developed attributes.Furthermore,there is a lack of UML-based models that can generate test cases from natural language requirements by rening them in context.Coverage criteria indicate how efciently the testing has been performed 12.37%of studies use requirements coverage,20%of studies cover path coverage,and 17%study basic coverage. 展开更多
关键词 Test case generation functional testing techniques requirementsbased test case generation system testing natural language requirement requirements tractability coverage criteria
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Effective Hybrid Content-Based Collaborative Filtering Approach for Requirements Engineering 被引量:1
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作者 Qusai Y.Shambour Abdelrahman H.Hussein +1 位作者 Qasem M.Kharma Mosleh M.Abualhaj 《Computer Systems Science & Engineering》 SCIE EI 2022年第1期113-125,共13页
Requirements engineering(RE)is among the most valuable and critical processes in software development.The quality of this process significantly affects the success of a software project.An important step in RE is requ... Requirements engineering(RE)is among the most valuable and critical processes in software development.The quality of this process significantly affects the success of a software project.An important step in RE is requirements elicitation,which involves collecting project-related requirements from different sources.Repositories of reusable requirements are typically important sources of an increasing number of reusable software requirements.However,the process of searching such repositories to collect valuable project-related requirements is time-consuming and difficult to perform accurately.Recommender systems have been widely recognized as an effective solution to such problem.Accordingly,this study proposes an effective hybrid content-based collaborative filtering recommendation approach.The proposed approach will support project stake-holders in mitigating the risk of missing requirements during requirements elicitation by identifying related requirements from software requirement repositories.The experimental results on the RALIC dataset demonstrate that the proposed approach considerably outperforms baseline collaborative filtering-based recom-mendation methods in terms of prediction accuracy and coverage in addition to mitigating the data sparsity and cold-start item problems. 展开更多
关键词 requirements engineering recommender systems requirements elicitation collaborative filtering content-based filtering
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Economical Requirements Elicitation Techniques During COVID-19: A Systematic Literature Review
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作者 Tauqeer ul Amin Basit Shahzad +1 位作者 Fazal-e-Amin Muhammad Shoaib 《Computers, Materials & Continua》 SCIE EI 2021年第5期2665-2680,共16页
Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and... Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and a project may fail if there are excessive costs and schedule overruns.COVID-19 has affected the software industry by reducing interactions between developers and customers.Such a lack of interaction is a key reason for the failure of software projects.Projects can also fail when customers do not know precisely what they want.Furthermore,selecting the unsuitable elicitation technique can also cause project failure.The present study,therefore,aimed to identify which requirements elicitation technique is the most cost-effective for large-scale projects when time to market is a critical issue or when the customer is not available.To that end,we conducted a systematic literature review on requirements elicitation techniques.Most primary studies identified introspection as the best technique,followed by survey and brainstorming.This finding suggests that introspection should be the first choice of elicitation technique,especially when the customer is not available or the project has strict time and cost constraints.Moreover,introspection should also be used as the starting point in the elicitation process of a large-scale project,and all known requirements should be elicited using this technique. 展开更多
关键词 COVID-19 software engineering requirements engineering requirements elicitation INTROSPECTION project failure SLR on elicitation techniques large-scale projects economical elicitation techniques costeffective time constraints
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Towards a Formalized Ontology-Based Requirements Model
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作者 蒋丹东 张申生 王英林 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期34-39,共6页
The goal of this paper is to take a further step towards an ontological approach for representing requirements information. The motivation for ontologies was discussed. The definitions of ontology and requirements ont... The goal of this paper is to take a further step towards an ontological approach for representing requirements information. The motivation for ontologies was discussed. The definitions of ontology and requirements ontology were given. Then, it presented a collection of informal terms, including four subject areas. It also discussed the formalization process of ontology. The underlying meta-ontology was determined, and the formalized requirements ontology was analyzed. This formal ontology is built to serve as a basis for requirements model. Finally, the implementation of software system was given. 展开更多
关键词 requirements ontology ONTOLOGY meta-ontology requirements model formalized
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A Requirements Engineering Environment for Embedded Real-Time Software—SREE
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作者 LI Yonghua SHU Fengdi +1 位作者 WU Guoqing LIANG Zhengping 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期533-538,共6页
The paper presents the embedded real-time software-oriented requirements engineering environment—SREZ. It involves the whole process of software requirements engineering, including the definition, analysis and checki... The paper presents the embedded real-time software-oriented requirements engineering environment—SREZ. It involves the whole process of software requirements engineering, including the definition, analysis and checking of requirements ,specifications. We first explain the principles of the executable specification language RTRSM. Subsequently, we introduce the main functions of SREE, illustrate the methods and techniques of checking requirements specifications, especially how to perform simulation execution, combining prototyping method with RTRSM and animated representations. At last, we compare the SREE with other requirements specifications methods and make a summary for SREE's advantages. 展开更多
关键词 embedded real-time system requirements specification requirements verification simulation execution
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Testing agile requirements models
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作者 BOTASCHANJANJewgenij PISTERMarkus RUMPEBernhard 《Journal of Zhejiang University Science》 CSCD 2004年第5期587-593,共7页
This paper discusses a model-based approach to validate software requirements in agile development processes by simulation and in particular automated testing. The use of models as central development artifact needs t... This paper discusses a model-based approach to validate software requirements in agile development processes by simulation and in particular automated testing. The use of models as central development artifact needs to be added to the portfolio of software engineering techniques, to further increase efficiency and flexibility of the development beginning already early in the requirements definition phase. Testing requirements are some of the most important techniques to give feedback and to increase the quality of the result. Therefore testing of artifacts should be introduced as early as possible, even in the requirements definition phase. 展开更多
关键词 requirements UML Model-based testing requirements evolution
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Crop water requirements of major crops indryland of northern China
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作者 ZHONG Zhao-zhan, ZHAO Ju-bao, JU Hui, YU Xiao-chuan(Agrometeorology Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第4期346-354,共9页
The concept of crop water requirements is discussed, based on which the calculation modelof crop water requirements is established. In light with crop, soil and meteorological data. the cropwater requirements of majo... The concept of crop water requirements is discussed, based on which the calculation modelof crop water requirements is established. In light with crop, soil and meteorological data. the cropwater requirements of major crops in sub-humid and send-arid dryland farming areas of northernChina. including wheat maize , cotton. millet, soybean, sweet potato and potato, are calculated, andthe patterns of crop water requirements of these crops are revealed and discussed in this paper. 展开更多
关键词 Northem China dryland crops crop water requirements pattern of crop waterrequirements
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Eliciting Requirements from Stakeholders’ Responses Using Natural Language Processing
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作者 Mohammed Lafi Bilal Hawashin Shadi AlZu’bi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第4期99-116,共18页
Most software systems have different stakeholders with a variety of concerns.The process of collecting requirements from a large number of stakeholders is vital but challenging.We propose an efficient,automatic approa... Most software systems have different stakeholders with a variety of concerns.The process of collecting requirements from a large number of stakeholders is vital but challenging.We propose an efficient,automatic approach to collecting requirements from different stakeholders’responses to a specific question.We use natural language processing techniques to get the stakeholder response that represents most other stakeholders’responses.This study improves existing practices in three ways:Firstly,it reduces the human effort needed to collect the requirements;secondly,it reduces the time required to carry out this task with a large number of stakeholders;thirdly,it underlines the importance of using of data mining techniques in various software engineering steps.Our approach uses tokenization,stop word removal,and word lemmatization to create a list of frequently accruing words.It then creates a similarity matrix to calculate the score value for each response and selects the answer with the highest score.Our experiments show that using this approach significantly reduces the time and effort needed to collect requirements and does so with a sufficient degree of accuracy. 展开更多
关键词 Software requirements requirements elicitation natural language processing
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Professional Requirements for Contemporary Teachers
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作者 丁丽红 《海外英语》 2011年第3X期135-136,共2页
The rapid development of high-tech based information technology marks the era of a knowledge-based economy. This form of economy, characterized by knowledge, has raised new demands for most teachers. To rise to the ch... The rapid development of high-tech based information technology marks the era of a knowledge-based economy. This form of economy, characterized by knowledge, has raised new demands for most teachers. To rise to the challenge, teachers must maintain innovative attitudes and practical abilities that will meet the social requirements. The writer examines the professional requirements for contemporary teachers in this paper. 展开更多
关键词 CONTEMPORARY TEACHERS PROFESSIONAL requirements teachers’ CULTURE
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An Approach towards Goal-Oriented Requirements Ontology: Consistency and Completeness Based Requirements Analysis
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作者 Mohammad Mustafa Taye Said Ghoul 《Journal of Software Engineering and Applications》 2023年第2期31-49,共19页
The paper presents a new approach to managing software requirement elicitation techniques with a high level of analyses based on domain ontology techniques, where we established a mapping between user scenario, struct... The paper presents a new approach to managing software requirement elicitation techniques with a high level of analyses based on domain ontology techniques, where we established a mapping between user scenario, structured requirement, and domain ontology techniques to improve many attributes such as requirement consistency, completeness and eliminating duplicate requirements to reduce risk of overrun time and budgets. One of the main targets of requirement engineering is to develop a requirement document with high quality. So, we proposed a user interface to collect all vital information about the project directly from the regular user and requirement engineering;After that, the proposal will generate an ontology based on semantic relations and rules. Requirements Engineering tries to keep requirements throughout a project’s life cycle consistent necessities clear, and up to date. This prototype allows mapping requirement scenarios into ontology elements for semantically interrupted. The general points of our prototype are to guarantee the identification requirements and improved nature of the Software Requirements Specification (SRS) by solving incomplete and conflicting information in the requirements specification. 展开更多
关键词 requirements Engineering requirements Elicitation Domain Ontology ONTOLOGY
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Dietary requirements of synthesizable amino acids by animals:a paradigm shift in protein nutrition 被引量:26
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作者 Guoyao Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第1期1-12,共12页
Amino acids are building blocks for proteins in all animals. Based on growth or nitrogen balance, amino acids were traditionally classified as nutritionally essential or nonessential for mammals, birds and fish. It wa... Amino acids are building blocks for proteins in all animals. Based on growth or nitrogen balance, amino acids were traditionally classified as nutritionally essential or nonessential for mammals, birds and fish. It was assumed that all the "nutritionally nonessential amino acids (NEAA)" were synthesized sufficiently in the body to meet the needs for maximal growth and optimal health. However, careful analysis of the scientific literature reveals that over the past century there has not been compelling experimental evidence to support this assumption. NEAA (e.g., glutamine, glutamate, proline, glycine and arginine) play important roles in regulating gene expression, cell signaling, antioxidative responses, fertility, neurotransmission, and immunity. Additionally, glutamate, glutamine and aspartate are major metabolic fuels for the small intestine to maintain its digestive function and to protect the integrity of the intestinal mucosa. Thus, diets for animals must contain all NEAA to optimize their survival, growth, development, reproduction, and health. Furthermore, NEAA should be taken into consideration in revising the "ideal protein" concept that is currently used to formulate swine and poultry diets. Adequate provision of all amino acids (including NEAA) in diets enhances the efficiency of animal production. In this regard, amino acids should not be classified as nutritionally essential or nonessential in animal or human nutrition. The new Texas A&M University's optimal ratios of dietary amino acids for swine and chickens are expected to beneficially reduce dietary protein content and improve the efficiency of their nutrient utilization, growth, and production performance. 展开更多
关键词 DIET METABOLISM NUTRITION Protein requirements
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Applying CBR to Machine Tool Product Configuration Design Oriented to Customer Requirements 被引量:12
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作者 WANG Pengjia GONG Yadong +2 位作者 XIE Hualong LIU Yongxian NEE Andrew Yehching 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第1期60-76,共17页
Product customization is a trend in the current market-oriented manufacturing environment. However, deduction from customer requirements to design results and evaluation of design alternatives are still heavily relian... Product customization is a trend in the current market-oriented manufacturing environment. However, deduction from customer requirements to design results and evaluation of design alternatives are still heavily reliant on the designer's experience and knowledge. To solve the problem of fuzziness and uncertainty of customer requirements in product configuration, an analysis method based on the grey rough model is presented. The customer requirements can be converted into technical characteristics effectively. In addition, an optimization decision model for product planning is established to help the enterprises select the key technical characteristics under the constraints of cost and time to serve the customer to maximal satisfaction. A new case retrieval approach that combines the self-organizing map and fuzzy similarity priority ratio method is proposed in case-based design. The self-organizing map can reduce the retrieval range and increase the retrieval efficiency, and the fuzzy similarity priority ratio method can evaluate the similarity of cases comprehensively. To ensure that the final case has the based on grey correlation analysis is proposed to evaluate similar cases best overall performance, an evaluation method of similar cases to select the most suitable case. Furthermore, a computer-aided system is developed using MATLAB GUI to assist the product configuration design. The actual example and result on an ETC series machine tool product show that the proposed method is effective, rapid and accurate in the process of product configuration. The proposed methodology provides a detailed instruction for the product configuration design oriented to customer requirements. 展开更多
关键词 customer requirements case-based reasoning machine tool case retrieval case evaluation computer-aided system
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Regional distribution of wheat yield and chemical fertilizer requirements in China 被引量:8
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作者 XU Xin-peng HE Ping +7 位作者 CHUAN Li-min LIU Xiao-yan LIU Ying-xia ZHANG Jia-jia HUANG Xiao-meng QIU Shao-jun ZHAO Shi-cheng ZHOU Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第10期2772-2780,共9页
Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a ... Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a total of 5408 field experiments were collected from 2000 to 2015 across the major wheat production regions in China to analyze the spatial distribution of wheat yield,the soil nutrient supply capacity(represented by relative yield,defined as the ratio of the yield under the omission of one of nitrogen(N),phosphorus(P)and potassium(K)to the yield under the full NPK fertilizer application),and N,P and K fertilizer requirements by combining the kriging interpolation method with the Nutrient Expert Decision Support System for Wheat.The results indicated that the average attainable yield was 6.4 t ha^(−1),with a coefficient of variation(CV)of 24.9% across all sites.The yields in North-central China(NCC)and the northern part of the Middle and Lower reaches of the Yangtze River(MLYR)were generally higher than 7 t ha^(−1),whereas the yields in Southwest China(SWC),Northeast China(NEC),and the eastern part of Northwest China(NWC)were usually less than 6 t ha^(−1).The precentage of area having a relative yield above 0.70,0.85,and 0.85 for N,P,and K fertilizers accounted for 52.3,74.7,and 95.9%,respectively.Variation existed in N,P,and K fertilizer requirements,with a CV of 24.8,23.9,and 29.9%,respectively,across all sites.More fertilizer was needed in NCC and the northern part of the MLYR than in other regions.The average fertilizer requirement was 162,72,and 57 kg ha^(−1) for N,P2O5,and K2O fertilizers,respectively,across all sites.The incorporation of the spatial variation of attainable yield and fertilizer requirements into wheat production practices would benefit sustainable wheat production and environmental safety. 展开更多
关键词 WHEAT attainable yield fertilizer requirements nutrient expert system spatial variation
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