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Correlation of Microbiological Stability with Redox Processes in White Wines
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作者 Gheorghe Duca Rodica Sturza +1 位作者 Natalia Vladei Ecaterina Covaci 《Food and Nutrition Sciences》 CAS 2024年第3期211-223,共13页
In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technologica... In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines. 展开更多
关键词 White Wines ACETOBACTER Sulfur Dioxide Redox processes OXYGEN
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Development and Validation of Integrated Nutrient Management Practices of Industrial Processing Varieties: Asterix and Courage in Bangladesh
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作者 Azizul Hoque Md. Maniruzzaman Sikder Abul Khair 《Agricultural Sciences》 2024年第7期780-799,共20页
An experiment was meticulously conducted at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh, during the 2011-2012 potato growing season to develop integrat... An experiment was meticulously conducted at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh, during the 2011-2012 potato growing season to develop integrated crop management practices for the potato seed production of industrial processing varieties Asterix and Courage. Significantly, higher growth and yield parameters were found in the BADC-recommended practice. Later, another experiment was conducted to validate the BADC practice during the 2013-2014 potato growing season in two locations in Bangladesh. Results showed that the production of tuber per hill, tuber weight per hill as well as gross tuber yield per plot, higher proportion of storable seed tubers, and more quality seed potatoes (A-grade and B-grade) seed tubers were found significantly higher in the “BADC developed practice” compared to other treatments. Viral diseases (PLRV and PVY) prevalence was lower in “BADC developed practice”. Moreover, “BADC developed practice” contributed more economic yield by minimizing input cost compared to “Munshiganj advanced farmers’ practice”. Therefore, the “BADC developed practice” was found “superior” regarding yield, quality, and profitability in seed potato production of industrial varieties—Asterix and Courage in Bangladesh. 展开更多
关键词 Integrated NUTRIENT Industrial processing POTATOES
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A Quality Evaluation System for Dissertation Based on Fuzzy Analytic Hierarchy Process
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作者 Kang Xu Zhenhao Zhang +4 位作者 Shuo Wang Yunhui Lv Jiafei Li Xiaodan Cai Yongchun Cui 《Applied Mathematics》 2024年第7期441-454,共14页
A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. T... A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. To construct an optimized quality evaluation system for postgraduate dissertation (QESPD), we summarized the influencing factors and invited 10 experienced specialists to rate and prioritize them based on fuzzy analytic hierarchy process. Four primary indicators (innovation, integrity, scientificity and normativity) and 16 sub-indicators were selected to form the evaluation system. The order of primary indicators by weight, was innovation (0.4269), scientificity (0.2807), integrity (0.1728) and normativity (0.1196). The top five sub-dimensions were theoretical originality, scientific value, data reliability, design rationality and evidence credibility. To demonstrate the effectiveness of the proposed system, a case study was performed. In the case study, it was demonstrated that the established two-index-hierarchy QESPD in this study was a more scientific and reasonable evaluation system worthy of promotion and application. 展开更多
关键词 DISSERTATION Quality Evaluation Indicator System Fuzzy Analytic Hierarchy process Case Study
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Optimization of the Pretreatment of the Mixture of Cassava Peelings and Pineapple Fibers Using Response Surface Methodology and a Process Simulator for the Bioethanol Production
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作者 Paul Nestor Djomou Djonga George Elambo Nkeng +2 位作者 Madjoyogo Hervé Sirma Ahmat Tom Thierry Tchamba Tchuidjang 《Energy and Power Engineering》 2024年第2期79-96,共18页
The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production ... The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production of bioethanol remains a challenge given the crystallinity of cellulose and the presence of the complex. The pretreatment aimed to solubilize the lignin fraction and to make cellulose more accessible to the hydrolytic enzymes, was done using the organosolv process. A mathematical modeling was performed to point out the effect of the temperature on the kinetics of the release of the reducing sugars during the pretreatment. Two mathematical model was used, SAEMAN’s model and Response surface methodology. The first show that the kinetic parameters of the hydrolysis of the cellulose and reducing sugar are: 0.05089 min<sup>-1</sup>, 5358.1461 J·mol<sup>-1</sup>, 1383.03691 min<sup>-1</sup>, 51577.6100 J·mol<sup>-1</sup> respectively. The second model was used. Temperature is the factor having the most positive influence whereas, ethanol concentration is not an essential factor. To release the maximum, an organosolv pre-treatment of this sub-strate should be carried out at 209.08°C for 47.60 min with an ethanol-water ratio of 24.02%. Organosolv pre-treatment is an effective process for delignification of the lignocellulosic structure. 展开更多
关键词 BIOETHANOL Cassava Peeling Pineapple Fibers Organosolv process and Optimization
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Study Progress Analysis of Effluent Quality Prediction in Activated Sludge Process Based on CiteSpace
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作者 Kemeng Xue 《Journal of Water Resource and Protection》 CAS 2024年第6期450-465,共16页
In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge pr... In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge process in the wastewater treatment. By the way of trend map, keyword knowledge map, and co-cited knowledge map, specific visualization analysis and identification of the authors, institutions and regions were concluded. Furthermore, the topics and hotspots of water quality prediction in activated sludge process through the literature-co-citation-based cluster analysis and literature citation burst analysis were also determined, which not only reflected the historical evolution progress to a certain extent, but also provided the direction and insight of the knowledge structure of water quality prediction and activated sludge process for future research. 展开更多
关键词 Biological Model Effluent Quality Prediction Activated Sludge process CITESPACE Knowledge Map Co-Citation Cluster Analysis
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Mapping Climate Services for Disaster Risk Management: A Systematic Review and Research Gaps from a Policy Process Perspective
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作者 Aboubacar Issaka Ousman Gaoh Wolfram Laube +1 位作者 Georges Abbevi Abbey Moussa Waongo 《American Journal of Climate Change》 2024年第2期314-360,共47页
Climate services (CS) are crucial for mitigating and managing the impacts and risks associated with climate-induced disasters. While evidence over the past decade underscores their effectiveness across various domains... Climate services (CS) are crucial for mitigating and managing the impacts and risks associated with climate-induced disasters. While evidence over the past decade underscores their effectiveness across various domains, particularly agriculture, to maximize their potential, it is crucial to identify emerging priority areas and existing research gaps for future research agendas. As a contribution to this effort, this paper employs the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to review the state-of-the-art in the field of climate services for disaster risk management. A comprehensive search across five literature databases combined with a snowball search method using ResearchRabbit was conducted and yielded 242 peer-reviewed articles, book sections, and reports over 2013-2023 after the screening process. The analysis revealed flood, drought, and food insecurity as major climate-related disasters addressed in the reviewed literature. Major climate services addressed included early warning systems, (sub)seasonal forecasts and impact-based warnings. Grounded in the policy processes’ theoretical perspective, the main focus identified and discussed three prevailing policy-oriented priority areas: 1) development of climate services, 2) use-adoption-uptake, and 3) evaluation of climate services. In response to the limitations of the prevalent supply-driven and top-down approach to climate services promotion, co-production emerges as a cross-cutting critical aspect of the identified priority areas. Despite the extensive research in the field, more attention is needed, particularly pronounced in the science-policy interface perspective, which in practice bridges scientific knowledge and policy decisions for effective policy processes. This perspective offers a valuable analytical lens as an entry point for further investigation. Hence, future research agendas would generate insightful evidence by scrutinizing this critical aspect given its importance to institutions and climate services capacity, to better understand intricate facets of the development and the integration of climate services into disaster risk management. 展开更多
关键词 Climate Services Disaster Risk Management Policy process Science-Policy Interface Institutional Analysis
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Parallel Image Processing: Taking Grayscale Conversion Using OpenMP as an Example
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作者 Bayan AlHumaidan Shahad Alghofaily +2 位作者 Maitha Al Qhahtani Sara Oudah Naya Nagy 《Journal of Computer and Communications》 2024年第2期1-10,共10页
In recent years, the widespread adoption of parallel computing, especially in multi-core processors and high-performance computing environments, ushered in a new era of efficiency and speed. This trend was particularl... In recent years, the widespread adoption of parallel computing, especially in multi-core processors and high-performance computing environments, ushered in a new era of efficiency and speed. This trend was particularly noteworthy in the field of image processing, which witnessed significant advancements. This parallel computing project explored the field of parallel image processing, with a focus on the grayscale conversion of colorful images. Our approach involved integrating OpenMP into our framework for parallelization to execute a critical image processing task: grayscale conversion. By using OpenMP, we strategically enhanced the overall performance of the conversion process by distributing the workload across multiple threads. The primary objectives of our project revolved around optimizing computation time and improving overall efficiency, particularly in the task of grayscale conversion of colorful images. Utilizing OpenMP for concurrent processing across multiple cores significantly reduced execution times through the effective distribution of tasks among these cores. The speedup values for various image sizes highlighted the efficacy of parallel processing, especially for large images. However, a detailed examination revealed a potential decline in parallelization efficiency with an increasing number of cores. This underscored the importance of a carefully optimized parallelization strategy, considering factors like load balancing and minimizing communication overhead. Despite challenges, the overall scalability and efficiency achieved with parallel image processing underscored OpenMP’s effectiveness in accelerating image manipulation tasks. 展开更多
关键词 Parallel Computing Image processing OPENMP Parallel Programming High Performance Computing GPU (Graphic processing Unit)
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HV Process Model of Software Development
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作者 Hemant Kumar Vipin Saxena 《Journal of Software Engineering and Applications》 2024年第7期553-570,共18页
Software Development Life Cycle (SDLC) is one of the major ingredients for the development of efficient software systems within a time frame and low-cost involvement. From the literature, it is evident that there are ... Software Development Life Cycle (SDLC) is one of the major ingredients for the development of efficient software systems within a time frame and low-cost involvement. From the literature, it is evident that there are various kinds of process models that are used by the software industries for the development of small, medium and long-term software projects, but many of them do not cover risk management. It is quite obvious that the improper selection of the software development process model leads to failure of the software products as it is time bound activity. In the present work, a new software development process model is proposed which covers the risks at any stage of the development of the software product. The model is named a Hemant-Vipin (HV) process model and may be helpful for the software industries for development of the efficient software products and timely delivery at the end of the client. The efficiency of the HV process model is observed by considering various kinds of factors like requirement clarity, user feedback, change agility, predictability, risk identification, practical implementation, customer satisfaction, incremental development, use of ready-made components, quick design, resource organization and many more and found through a case study that the presented approach covers many of parameters in comparison of the existing process models. . 展开更多
关键词 Software process Model Software Development Software Engineering Software Risk Management and Software Quality
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Parallel Technologies with Image Processing Using Inverse Filter
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作者 Rahaf Alsharhan Areej Muheef +2 位作者 Yasmin Al Ibrahim Afnan Rayyani Yasir Alguwaifli 《Journal of Computer and Communications》 2024年第1期110-119,共10页
Real-time capabilities and computational efficiency are provided by parallel image processing utilizing OpenMP. However, race conditions can affect the accuracy and reliability of the outcomes. This paper highlights t... Real-time capabilities and computational efficiency are provided by parallel image processing utilizing OpenMP. However, race conditions can affect the accuracy and reliability of the outcomes. This paper highlights the importance of addressing race conditions in parallel image processing, specifically focusing on color inverse filtering using OpenMP. We considered three solutions to solve race conditions, each with distinct characteristics: #pragma omp atomic: Protects individual memory operations for fine-grained control. #pragma omp critical: Protects entire code blocks for exclusive access. #pragma omp parallel sections reduction: Employs a reduction clause for safe aggregation of values across threads. Our findings show that the produced images were unaffected by race condition. However, it becomes evident that solving the race conditions in the code makes it significantly faster, especially when it is executed on multiple cores. 展开更多
关键词 PARALLEL PARALLELIZATION Image processing Inverse Filtering OPENMP Race Conditions
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Research on Image Preprocessing Algorithm for Rail Surface Recognition
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作者 Jihong Zuo Lili Liu +1 位作者 Chuanyin Yang Yufeng Tang 《Open Journal of Applied Sciences》 2024年第10期2801-2808,共8页
The rail surface status image is affected by the noise in the shooting environment and contains a large amount of interference information, which increases the difficulty of rail surface status identification. In orde... The rail surface status image is affected by the noise in the shooting environment and contains a large amount of interference information, which increases the difficulty of rail surface status identification. In order to solve this problem, a preprocessing method for the rail surface state image is proposed. The preprocessing process mainly includes image graying, image denoising, image geometric correction, image extraction, data amplification, and finally building the rail surface image database. The experimental results show that this method can efficiently complete image processing, facilitate feature extraction of rail surface status images, and improve rail surface status recognition accuracy. 展开更多
关键词 Image processing Image Graying Image Denoising Image Database
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Non-Recursive Base Conversion Using a Deterministic Markov Process
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作者 Louis M. Houston 《Journal of Applied Mathematics and Physics》 2024年第6期2112-2118,共7页
We prove that non-recursive base conversion can always be implemented by using a deterministic Markov process. Our paper discusses the pros and cons of recursive and non-recursive methods, in general. And we include a... We prove that non-recursive base conversion can always be implemented by using a deterministic Markov process. Our paper discusses the pros and cons of recursive and non-recursive methods, in general. And we include a comparison between non-recursion and a deterministic Markov process, proving that the Markov process is twice as efficient. 展开更多
关键词 Base Conversion RECURSION Euclidean Division Geometric Series Markov process
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Robotic Process Automation with New Future Trends
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作者 Abu Tayab Yanwen Li 《Journal of Computer and Communications》 2024年第6期12-24,共13页
The invention concept of Robotic Process Automation (RPA) has emerged as a transformative technology that has revolved the local business processes by programming repetitive task and efficiency adjusting the operation... The invention concept of Robotic Process Automation (RPA) has emerged as a transformative technology that has revolved the local business processes by programming repetitive task and efficiency adjusting the operations. This research had focused on developing the RPA environment and its future features in order to elaborate on the projected policies based on its comprehensive experiences. The current and previous situations of industry are looking for IT solutions to fully scale their company Improve business flexibility, improve customer satisfaction, improve productivity, accuracy and reduce costs, quick scalability in RPA has currently appeared as an advance technology with exceptional performance. It emphasizes future trends and foresees the evolution of RPA by integrating artificial intelligence, learning of machine and cognitive automation into RPA frameworks. Moreover, it has analyzed the technical constraints, including the scalability, security issues and interoperability, while investigating regulatory and ethical considerations that are so important to the ethical utilization of RPA. By providing a comprehensive analysis of RPA with new future trends in this study, researcher’s ambitions to provide valuable insights the benefits of it on industrial performances from the gap observed so as to guide the strategic decision and future implementation of the RPA. 展开更多
关键词 Robotic process Automation Artificial Intelligence Machine Learning Cognitive Computing INTEROPERABILITY Data Security
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基于Processing的何香凝艺术参与式创新转化应用研究
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作者 凌杰 《湖南包装》 2023年第6期33-36,43,共5页
以何香凝艺术为对象,分析了其在创造性转化中存在的问题。通过研究运用Processing技术和参与式设计对创造性转化的潜力,发现Processing技术和参与式设计相互协作,可以成为何香凝艺术发展的双重推动力。基于这一发现,提出了一种基于Proce... 以何香凝艺术为对象,分析了其在创造性转化中存在的问题。通过研究运用Processing技术和参与式设计对创造性转化的潜力,发现Processing技术和参与式设计相互协作,可以成为何香凝艺术发展的双重推动力。基于这一发现,提出了一种基于Processing的何香凝艺术参与式创新转化应用策略,旨在促进何香凝艺术的创新转化。该策略将Processing技术与参与式设计相结合,提供了一种新的途径,以增加公众对何香凝艺术的参与度和认知度,进而推动其在当代社会中的发展和扩大影响力。 展开更多
关键词 参与式设计 生成艺术 何香凝 创新性转化 processING
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基于Arduino与Processing互动编程的特种仓库智能测控系统设计 被引量:2
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作者 崔北尧 王峰 +2 位作者 刘士军 李伟光 王一飞 《现代电子技术》 2023年第18期177-182,共6页
基于Arduino与Processing互动编程方式进行特种仓库智能测控系统设计。该系统以Arduino为主控单元,利用各种传感器实时采集库区火情、烟雾、温度、湿度、有害气体浓度等关键参数;采用中位值平均滤波法对参数进行处理,并根据库内参数发... 基于Arduino与Processing互动编程方式进行特种仓库智能测控系统设计。该系统以Arduino为主控单元,利用各种传感器实时采集库区火情、烟雾、温度、湿度、有害气体浓度等关键参数;采用中位值平均滤波法对参数进行处理,并根据库内参数发出相应控制信号,作用于对应节点设备,实现自动控制。同时,保留人工干预措施,仓库管理人员可以根据库内环境参数做出相应的管控措施。所设计系统是集常规监测、自动控制、无人值班等功能于一体的智能化系统,对弹药、危险品、生化物品等高危物品的存储有一定的借鉴意义。 展开更多
关键词 特种仓库智能测控系统 Arduino芯片 processING 温湿度传感器 自动控制 算术平均滤波 程序设计
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中国铁矿石选矿技术发展与展望 被引量:10
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作者 韩跃新 张小龙 +2 位作者 高鹏 李艳军 孙永升 《金属矿山》 CAS 北大核心 2024年第2期1-24,共24页
铁矿石作为钢铁工业最为重要的原材料,是我国重要的战略性矿产资源之一。我国铁矿资源储量丰富,但97%以上属于贫矿,需要经过选矿富集后才能供给高炉炼铁。多年来,在我国选矿工作者的共同努力下,我国铁矿选矿技术得到长足进步和发展。通... 铁矿石作为钢铁工业最为重要的原材料,是我国重要的战略性矿产资源之一。我国铁矿资源储量丰富,但97%以上属于贫矿,需要经过选矿富集后才能供给高炉炼铁。多年来,在我国选矿工作者的共同努力下,我国铁矿选矿技术得到长足进步和发展。通过回顾我国铁矿选矿技术的发展历程,综述单一弱磁选、单一浮选、重选—磁选—反浮选、磁化焙烧—磁选等主要选矿技术在我国铁矿选矿厂的应用,总结我国典型多金属共生型铁矿石如伴生稀土/萤石型铁矿石、伴生钛铁矿型铁矿石、伴生多金属硫化物型铁矿石和伴生硼铁矿型铁矿石的选矿现状,介绍影响我国铁矿选矿技术进步的关键设备如圆锥破碎机、高压辊磨机、半自磨机、立环脉动高梯度磁选机、高频振动细筛、搅拌磨机等,指出我国铁矿选矿未来要以“高效节能、低碳减排”为原则,以“优质优用、劣质能用”为战略,开发选冶联合工艺,研发大型高效设备,研制低温环保药剂,提高智能控制水平,加强资源综合利用。 展开更多
关键词 铁矿石 选矿技术 高效利用 低碳环保 智能控制
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凝固剂及加工条件对豆腐凝胶形成及品质影响研究进展 被引量:4
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作者 孙冰玉 郑欣茹 +6 位作者 刘琳琳 吕铭守 黄雨洋 朱颖 曲敏 朱秀清 石彦国 《食品工业科技》 CAS 北大核心 2024年第3期388-396,共9页
豆腐的本质是一种蛋白质凝胶体,是大豆蛋白(主要是7S和11S球蛋白)在热处理下发生变性使蛋白质分子结构展开,再通过盐离子、氢离子或酶等凝固剂作用下发生聚集,形成致密均匀且具有网状结构蛋白凝胶。豆腐凝胶的形成及豆腐品质受多种因素... 豆腐的本质是一种蛋白质凝胶体,是大豆蛋白(主要是7S和11S球蛋白)在热处理下发生变性使蛋白质分子结构展开,再通过盐离子、氢离子或酶等凝固剂作用下发生聚集,形成致密均匀且具有网状结构蛋白凝胶。豆腐凝胶的形成及豆腐品质受多种因素的影响。本文从凝固剂种类(盐类、酸类和酶类凝固剂)以及加工条件(加工原料、制浆方法、豆浆体系pH、热处理条件)角度出发,阐明凝固剂及加工条件对豆腐凝胶形成以及品质的影响研究进展。以期为豆腐制品的工业化生产提供理论指导,为豆腐食品的研究开发与品质调控提供科学依据。 展开更多
关键词 豆腐凝胶 凝固剂 加工条件 形成机理 品质调控
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Study on Licker-In and Flat Speeds of Carding Machine and Its Effects on Quality of Cotton Spinning Process 被引量:1
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作者 Md. Mominul Motin Ayub Nabi Khan Md. Obaidur Rahman 《Journal of Textile Science and Technology》 2023年第3期198-214,共17页
Spinning has a significant influence on all textile processes. Combinations of all the capital equipment display the process’ critical condition. By transforming unprocessed fibers into carded sliver and yarn, the ca... Spinning has a significant influence on all textile processes. Combinations of all the capital equipment display the process’ critical condition. By transforming unprocessed fibers into carded sliver and yarn, the carding machine serves a critical role in the textile industry. The carding machine’s licker-in and flat speeds are crucial operational factors that have a big influence on the finished goods’ quality. The purpose of this study is to examine the link between licker-in and flat speeds and how they affect the yarn and carded sliver quality. A thorough experimental examination on a carding machine was carried out to accomplish this. The carded sliver and yarn produced after experimenting with different licker-in and flat speed combinations were assessed for important quality factors including evenness, strength, and flaws. To account for changes in material qualities and machine settings, the study also took into consideration the impact of various fiber kinds and processing circumstances. The findings of the investigation showed a direct relationship between the quality of the carded sliver and yarn and the licker-in and flat speeds. Within a limited range, greater licker-in speeds were shown to increase carding efficiency and decrease fiber tangling. On the other hand, extremely high speeds led to more fiber breakage and neps. Higher flat speeds, on the other hand, helped to enhance fiber alignment, which increased the evenness and strength of the carded sliver and yarn. Additionally, it was discovered that the ideal blend of licker-in and flat rates varied based on the fiber type and processing circumstances. When being carded, various fibers displayed distinctive behaviors that necessitated adjusting the operating settings in order to provide the necessary quality results. The study also determined the crucial speed ratios between the licker-in and flat speeds that reduced fiber breakage and increased the caliber of the finished goods. The results of this study offer useful information for textile producers and process engineers to improve the quality of carded sliver and yarn while maximizing the performance of carding machines. Operators may choose machine settings and parameter adjustments wisely by knowing the impacts of licker-in and flat speeds, which will increase textile industry efficiency, productivity, and product quality. 展开更多
关键词 Spinning process Carding Machine Yarn Count FLAT Licker-In Sliver Hank
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自然语言处理领域中的词嵌入方法综述 被引量:7
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作者 曾骏 王子威 +2 位作者 于扬 文俊浩 高旻 《计算机科学与探索》 CSCD 北大核心 2024年第1期24-43,共20页
词嵌入作为自然语言处理任务的第一步,其目的是将输入的自然语言文本转换为模型可以处理的数值向量,即词向量,也称词的分布式表示。词向量作为自然语言处理任务的根基,是完成一切自然语言处理任务的前提。然而,国内外针对词嵌入方法的... 词嵌入作为自然语言处理任务的第一步,其目的是将输入的自然语言文本转换为模型可以处理的数值向量,即词向量,也称词的分布式表示。词向量作为自然语言处理任务的根基,是完成一切自然语言处理任务的前提。然而,国内外针对词嵌入方法的综述文献大多只关注于不同词嵌入方法本身的技术路线,而未能将词嵌入的前置分词方法以及词嵌入方法完整的演变趋势进行分析与概述。以word2vec模型和Transformer模型作为划分点,从生成的词向量是否能够动态地改变其内隐的语义信息来适配输入句子的整体语义这一角度,将词嵌入方法划分为静态词嵌入方法和动态词嵌入方法,并对此展开讨论。同时,针对词嵌入中的分词方法,包括整词切分和子词切分,进行了对比和分析;针对训练词向量所使用的语言模型,从概率语言模型到神经概率语言模型再到如今的深度上下文语言模型的演化,进行了详细列举和阐述;针对预训练语言模型时使用的训练策略进行了总结和探讨。最后,总结词向量质量的评估方法,分析词嵌入方法的当前现状并对其未来发展方向进行展望。 展开更多
关键词 词向量 词嵌入方法 自然语言处理 语言模型 分词 词向量评估
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月球资源开发利用的进展与展望 被引量:5
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作者 杨孟飞 邹志刚 +2 位作者 汪卫华 姚伟 王庆功 《中国空间科学技术》 CSCD 北大核心 2024年第1期1-10,共10页
中国探月工程“绕、落、回”三步走圆满收官,后续将建立国际月球科研站,并进一步规划建立月球基地。月球探测任务由探测勘察进入到开发利用新阶段,月面资源的勘查、开发和利用是未来月球探测的重点任务。总结了月球资源开发利用方面的... 中国探月工程“绕、落、回”三步走圆满收官,后续将建立国际月球科研站,并进一步规划建立月球基地。月球探测任务由探测勘察进入到开发利用新阶段,月面资源的勘查、开发和利用是未来月球探测的重点任务。总结了月球资源开发利用方面的国内外重要进展,涉及月球资源勘探、水冰等挥发分分析、月球矿物冶炼与材料制备、月面建造与月壤3D打印等四个方面。同时,月球资源开发利用面临极端月面环境、独特月壤理化特性、全流程无人自主控制等重大挑战,为解决这些问题,提出了未来月球资源开发利用的重点任务和研究思路,可为后续科学研究和工程任务实施提供参考。 展开更多
关键词 月球资源 开发利用 勘探 矿物开采 水冰提取 月面建造
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无人机多光谱影像的小麦倒伏信息多特征融合检测研究 被引量:3
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作者 朱文静 冯展康 +4 位作者 戴世元 张平平 嵇文 王爱臣 魏新华 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第1期197-206,共10页
为探究多特征融合方法在作物倒伏领域快速精准识别中的适用性,利用无人机获取多田块冠层尺度的不同倒伏率麦田多光谱数据,对原始倒伏图像进行图像拼接、辐射校正、几何校正等预处理,并利用重归一化差值植被指数和阴影指数分别剔除土壤... 为探究多特征融合方法在作物倒伏领域快速精准识别中的适用性,利用无人机获取多田块冠层尺度的不同倒伏率麦田多光谱数据,对原始倒伏图像进行图像拼接、辐射校正、几何校正等预处理,并利用重归一化差值植被指数和阴影指数分别剔除土壤和阴影背景,提取小麦倒伏DSM模型和植被指数分别与多光谱图像进行多特征图像主成分变换融合,筛选差异性较大的纹理特征,采用支持向量机(SVM)、人工神经网络(ANN)和最大似然法(MLC)监督分类模型对多光谱和DSM融合图像、多光谱和归一化植被指数(NDVI)融合图像、多光谱图像和纹理特征图像进行监督分类,并采用总体精度(OA)、 Kappa系数和提取误差综合评价各监督模型的分类性能和倒伏提取精度。分类结果表明:各监督分类方法在不同倒伏区域提取结果建模效果趋势一致,SVM和ANN整体提取精度高于MLC,在高倒伏区域,多光谱与NDVI融合图像的SVM监督模型(OA:92.63%, Kappa系数:0.85,提取误差:1.11%)提取效果最好;在中倒伏区域,多光谱与DSM融合图像的SVM监督模型(OA:90.35%, Kappa系数:0.79,提取误差:9.34%)提取效果最好;在低倒伏区域,均值纹理特征图像的ANN监督模型(OA:91.05%, Kappa系数:0.82,提取误差:8.20%)提取结果较好。本研究将DSM模型、植被指数、纹理特征与多光谱图像进行融合对比,并对多特征融合方法能否高精度有效提取小麦倒伏信息进行了探究,结果表明无人机多光谱遥感结合特征融合技术能有效提取小麦倒伏面积,提取效果优于单特征小麦倒伏图像。本研究结果可为助力小麦倒伏灾情调查数据的精确获取方法提供参考。 展开更多
关键词 无人机遥感 图像处理 多光谱 特征融合 倒伏 小麦
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