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Community-led total sanitation(CLTS)implementation in West Mamprusi Municipal Assembly in Ghana.What do communities think eleven years on?
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作者 Elijah Adam Emmanuel Badu 《Global Health Journal》 2024年第2期67-73,共7页
Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)stil... Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)still have no access to adequate toilet facilities.This has brought untold health repercussions to the inhabitants,the community,and the environment at large.To address this menace,the community-led total sanitation(CLTS)was implemented.This study aimed to assess communities’perspectives on the implementation of CLTS and to understand the factors influencing its success and failures.Methods A mixed-method approach involving sequential qualitative and quantitative methods was employed in this study.Participants for the quantitative study were randomly selected and surveyed using questionnaires.The qualitative study employed focus group discussion involving purposively sampled participants including assembly members,opinion leaders,and assembly staff.Results The CLTS program in WMMA realized an apparent use of construction and proper use of household latrines leading to a reduction of open defecation free(ODF)and two communities achieving sanitized status in the history of the study area,enabling the training of latrine artisans and natural leaders to facilitate the CLTS expansion and sustainability,improved sanitation and hygiene,strengthened the enforcement of community rules and regulations and many others.Conclusion The CLTS program has received more widespread acceptance in the study area than the previous government policy of constructing public toilets,which was greeted with massive failures due to poor implementation.To ensure that gains achieved through CLTS implementation are sustained longer,it is recommended that chiefs and opinion leaders should be involved in the CLTS programs to ensure checks and enforcement.The entrenchment of bylaws and more education to address enduring myths and misconceptions will sustain the program.Subsidies in the form of sanitation loans for latrine construction materials by the government and supporting non-governmental organizations(NGOs)will be paramount in sustaining ODF. 展开更多
关键词 Community-led total sanitation(CLTS) Community development Ghana sanitation
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Rural Resilience: A Comprehensive Study on Water Supply, Sanitation, Disease Patterns, and Hygiene Practices in Munshiganj, Bangladesh
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作者 Jubayer Hoque Rifat Islam +6 位作者 Md. Mustafizur Rahman Md. Golam Rabbani Md. Selim Reja Saifur Rahman Soykat Saim Raiyan Md. Shafiqul Ahsan Emon Sakil Khan 《Journal of Environmental Protection》 2024年第1期63-75,共13页
This research project investigates the current status of water supply, sanitation, and hygiene practices in Munshiganj District, Bangladesh. Data collection involved a structured questionnaire and a reconnaissance sur... This research project investigates the current status of water supply, sanitation, and hygiene practices in Munshiganj District, Bangladesh. Data collection involved a structured questionnaire and a reconnaissance survey. Findings reveal that 30% of individuals rely on surface water (hand-tube wells, rivers, and ponds), prioritized as canal > river > pond, while 70% depend on groundwater (subterranean electric motor, deep tube-well). Drinking water is generally sufficient, with 95% reporting adequacy throughout the year. About 45% use hand tube-well water, 28% use deep tube-well water, and 11% use supply tap water for various purposes. Bathing trends include underground water through electric motor > pond > hand tube-well water > river, while for cooking, the order is underground water through electric motor > pond > hand tube-well water > river. Toilet water supply ranks as supply tap water > hand tube-well water > deep tube-well water. Although sanitation awareness is high, some lack knowledge of good hygiene practices. After defecating, handwashing methods include soap, ash, soil, or water. Children’s waste disposal varies, with some discarding it in open areas. Approximately 40% suffer from diseases like Diarrhoea due to unsafe water, primarily affecting children and elders. Training exists, but a significant portion lacks sanitation education. Dry skin or exposure to cold water may cause temporary irritation. Local government involvement in sanitation efforts is less active compared to non-governmental organizations. Results emphasize the need to enhance community awareness of safe water supplies and sanitation practices. . 展开更多
关键词 Water Supply sanitation Practices Hygiene Awareness Groundwater Dependency Community Health Intervention
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Perception of the Mechanization of Rice Cultivation and Its Effects on the Soil in the Senegal River Valley
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作者 Cheick Atab Mane Siré Diedhiou +2 位作者 Arfang Ousmane Kémo Goudiaby Mohamed Sall Guillaume Gillet 《Agricultural Sciences》 2024年第6期704-718,共15页
In Senegal, particularly in the Senegal River valley, agricultural mechanization remains limited, mainly due to a lack of agricultural equipment, a lack of expertise in agricultural machinery and an apprehension of th... In Senegal, particularly in the Senegal River valley, agricultural mechanization remains limited, mainly due to a lack of agricultural equipment, a lack of expertise in agricultural machinery and an apprehension of the consequences on soil quality. To better understand agricultural mechanization of rice cultivation, this survey study has been carried out in the Senegal river valley. Precisely, this work aimed to characterize farm machinery and its effects on soil and rice cultivation. A questionnaire was administered to 304 out of 1270 farmers, spread over 8 rice-growing areas, 4 of which are located in the Podor department, three in Dagana and one in Saint-Louis. The results showed that 99.3% of farmers used motorized equipment, with 95.7% using tractor and 3.6% a power tiller. Offset tillage, which is a shallow cultivation practice carried out to break up hard soil without turning it over, was most widespread among growers (95.4%). 78.3% of the valley’s farmers felt that the machinery used to carry out tillage operations was inefficient. According to the farmers, the main constraints on the use of agricultural machinery in the valley were: the upkeep and maintenance of equipment (57%), the lack of expertise in mechanization (31%), and issues adapting machinery to local conditions (12%). Those constraints have contributed to a drop in yields in recent years, the spread of weeds on cultivated plots and the gradual degradation of the soil in the area according to 78% of farmers. 展开更多
关键词 Agricultural mechanization Characterization Constraints SOIL RICE
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Sustainable agricultural mechanization in Timor-Leste:status,challenges and further action
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作者 Jelle Van Loon Mayling Flores Rojas 《Circular Agricultural Systems》 2024年第1期57-66,共10页
Despite many efforts over two decades of independence,Timor-Leste's cereal production and agricultural productivity have decreased dramatically,reflected by high food insecurity and rural poverty.This paper analys... Despite many efforts over two decades of independence,Timor-Leste's cereal production and agricultural productivity have decreased dramatically,reflected by high food insecurity and rural poverty.This paper analyses the country's current agricultural mechanization efforts to guide future actions that aim to stimulate growth through sustainable mechanization.We combined information from scientific publications,governmental and international cooperation communications,and data collected during field missions to assess the situation.Our study provides recommendations to reverse a failed tractorization campaign and presents a comprehensive overview of a strategy,in alignment with a proposed and renewed national agricultural mechanization policy,that would enable the modernization and sustainable intensification of current food production systems in a nutrition-sensitive,climate-smart,economically viable,and gender-inclusive fashion.The recommendations suggest a focus on scale-appropriate solutions that respond to upland smallholder farmers'capacities and consider good rural transport options,with the first steps to redirect the situation already taken through a technical cooperation program between FAO and the Ministry of Agriculture.Beyond this,a reform of the current government mechanization hire schemes is needed:integrated approaches,as found from business model analyses and training exercises during field missions,are needed,that entail context-specific solutions for targeted rural communities,with special attention given to participatory extension,inclusive co-validation of technologies,and private sector-led business model development around mechanization service delivery.Finally,the authors hope the presented way forward can serve as a roadmap for smallholder farmers and developing nations in similar conditions elsewhere in the world. 展开更多
关键词 SUSTAINABLE AGRICULTURAL mechanization
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A Device to Improve Collaborative Practices of Sanitation Department Agents of a Territory: The Case of the Lamkansa District in Casablanca
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作者 Abdessalam Hijab Hafida Boulekbache Eric Henry 《Intelligent Information Management》 2023年第1期24-46,共23页
The aim of this article is to strengthen and improve the collaboration between professional agents of a service that manages one of the technical processes acting on a given territory by synchronizing the spatio-tempo... The aim of this article is to strengthen and improve the collaboration between professional agents of a service that manages one of the technical processes acting on a given territory by synchronizing the spatio-temporal dimensions including all agents assembled for the task. This proposal was tested in the Lamkansa neighborhood in Casablanca, Morocco. The employed approach is based GIS resources and on systemic analysis of communication present in a territory. We were inspired by several methodological developments that carried multi-actor processes in land use planning. We focused our work on strengthening the collaboration between professionals, field agents and office agents, in the process of design and monitoring the liquid sanitation system. The device is based on geolocation and synchronous feedback of topological, geographical, and multimedia data related to the liquid sanitation network. Thanks to a geo-collaborative, participative, and motivating logic, we reduced the management costs of the network and made it faster and more efficient by equally mobilizing another type of non-specialized actors (the inhabitants). This device uses spatial and temporal dimensions to consolidate collaborative work tools through ICT and GIS technologies that thematize and exchange information collected in the field. Furthermore, this device raises great interest as it entails the concept of integration of several actors in a geo-collaborative mode while combining geomatics with communication and information sciences. 展开更多
关键词 DEVICE ICT GIS Collaborative Practices Spatialized Information Synchronization Professional Agents Technical Processes sanitation Environment TERRITORY
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Factors Affecting the Adoption of Agricultural Mechanization Technologies by Women Farmers in the Karaga District of Ghana
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作者 Emelia Guo Mamudu A. Akudugu 《Agricultural Sciences》 2023年第9期1238-1248,共11页
Labour-saving or mechanization technologies have become the driving force behind modern agriculture, yet adoption of these technologies remains low in many parts of the developing world, particularly among female farm... Labour-saving or mechanization technologies have become the driving force behind modern agriculture, yet adoption of these technologies remains low in many parts of the developing world, particularly among female farmers in Ghana. This study aims to investigate the factors that hinder the adoption of agricultural mechanization technologies by female farmers in the Karaga District of the Northern Region of Ghana. This region is known for its large agricultural lands and significant role in commercial farming. The research was conducted using qualitative research methodology and involved interviewing 60 female farmers using an interview guide. The principle of sample saturation was used, meaning that further interviews were deemed unnecessary after the 60th interview. The results showed that low adoption of agricultural mechanization technologies is due to poor access to commercial lands, gender biases, lack of access to credit, and poor awareness about the benefits of these technologies. In conclusion, the low adoption of agricultural mechanization technologies is preventing women farmers in the Karaga District and elsewhere in Ghana from fully participating in commercial agricultural production. It is recommended that gender biases and cultural stereotypes be addressed to improve women farmers’ access to lands and credit, which will facilitate the adoption of mechanization technologies and lead to improved agricultural production. 展开更多
关键词 ADOPTION Agricultural mechanization Women Farmers Ghana Karaga District
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基于ProE的联合收割机二级齿轮减速器仿真分析 被引量:1
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作者 靳峰峰 唐光胤 《农机化研究》 北大核心 2024年第2期255-259,共5页
针对联合收割机二级齿轮减速器总体结构进行了设计,基于Pro/E建立了二级齿轮减速器模型并完成了产品的装配,最后利用Pro/E Mechanism仿真模块对所设计产品进行了运动仿真。结果表明:模型满足设计需求,具有较好的稳定性,对二级齿轮减速... 针对联合收割机二级齿轮减速器总体结构进行了设计,基于Pro/E建立了二级齿轮减速器模型并完成了产品的装配,最后利用Pro/E Mechanism仿真模块对所设计产品进行了运动仿真。结果表明:模型满足设计需求,具有较好的稳定性,对二级齿轮减速器进一步的优化设计具有一定参考作用。 展开更多
关键词 联合收割机 二级齿轮减速器 PRO/E 运动仿真 MECHANISM
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基于知识模糊迁徙的城市污水处理膜污染决策
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作者 何政 赵楠 +5 位作者 李杰 陈行行 阜崴 顾剑 韩红桂 刘峥 《北京工业大学学报》 CAS CSCD 北大核心 2024年第3期299-306,共8页
针对城市污水处理膜污染难以精准决策的问题,提出一种基于知识模糊迁徙的膜污染决策方法。首先,结合城市污水处理运行过程数据和运行经验,利用模糊规则的形式实现膜污染决策知识的表达;其次,提出一种知识重构机制(knowledge reconstruct... 针对城市污水处理膜污染难以精准决策的问题,提出一种基于知识模糊迁徙的膜污染决策方法。首先,结合城市污水处理运行过程数据和运行经验,利用模糊规则的形式实现膜污染决策知识的表达;其次,提出一种知识重构机制(knowledge reconstruction mechanism,KRM),动态平衡源域与目标域之间的准确性和多样性,并采用知识迁徙的方法完成决策知识重构;最后,建立一种基于数据和知识驱动的区间二型模糊神经网络(data-knowledge-driven interval type-2 fuzzy neural network,DK-IT2FNN)的决策模型,利用模糊规则设计模型参数,采用迁徙梯度下降算法动态调整网络权值,提高决策精度。实验结果表明,该模型能够实现膜污染的精准决策。 展开更多
关键词 城市污水处理 膜污染 知识重构机制(knowledge reconstruction mechanism KRM) 模糊神经网络 模糊迁徙 梯度下降算法
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椰壳纤维加筋土遗址生态注浆材料的性能 被引量:3
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作者 芦苇 骆望 +2 位作者 李东波 刘秦龙 刘加平 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第1期90-98,共9页
为提升土遗址注浆料的力学性能,以椰壳纤维掺和糯米浆、烧料礓石以及黄土改性注浆料为研究对象,研究了椰壳纤维长度和掺量(质量分数)对土遗址注浆料流动性、收缩性、抗压强度和抗折强度的影响.结果表明:椰壳纤维的掺量和长度越大,浆体... 为提升土遗址注浆料的力学性能,以椰壳纤维掺和糯米浆、烧料礓石以及黄土改性注浆料为研究对象,研究了椰壳纤维长度和掺量(质量分数)对土遗址注浆料流动性、收缩性、抗压强度和抗折强度的影响.结果表明:椰壳纤维的掺量和长度越大,浆体的流动性越低,而椰壳纤维的长度与浆体的收缩率无明显相关性;椰壳纤维良好的桥接能力可以有效提高浆体固化后的抗压强度、抗折强度和延性;椰壳纤维的长度和掺量均存在最优值,建议最优配比为纤维长度6 mm、掺量0.5%~0.6%,此时浆体固化后的抗压强度、抗折强度分别提升49.09%和32.08%;过多、过长的椰壳纤维易发生弯折、团聚,导致浆体的流动性和强度大幅降低. 展开更多
关键词 椰壳纤维 土遗址 生态注浆材料 力学性能 增强机理
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Al-Mg系合金中合金化元素作用及其对力学性能的影响 被引量:2
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作者 赵飞 黄文森 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期1-11,18,F0002,共13页
铝镁合金是轻量化材料应用领域中一种重要的金属材料,属于中高强度铝合金,具有较高的塑性、良好的耐蚀性以及优良的焊接性等优势,目前在航空航天、交通运输和军工制造等领域具有广阔的应用前景。笔者综述了铝镁合金力学性能特点以及用途... 铝镁合金是轻量化材料应用领域中一种重要的金属材料,属于中高强度铝合金,具有较高的塑性、良好的耐蚀性以及优良的焊接性等优势,目前在航空航天、交通运输和军工制造等领域具有广阔的应用前景。笔者综述了铝镁合金力学性能特点以及用途,介绍了Al-Mg系合金中的强化机制,重点阐述了Al-Mg系合金中主合金化元素Mg及其含量对合金微观组织和力学性能的影响规律及机理,详细论述了Mn、Zr、Ti、Sc、Er、Y等微合金化元素的作用以及对Al-Mg系合金微观组织和力学性能的影响规律。最后,结合Al-Mg系合金当前研究现状,提出了今后值得研究的方向。 展开更多
关键词 Al-Mg系合金 合金化 强化机制 力学性能
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基于RoBERTa和图增强Transformer的序列推荐方法 被引量:2
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作者 王明虎 石智奎 +1 位作者 苏佳 张新生 《计算机工程》 CAS CSCD 北大核心 2024年第4期121-131,共11页
自推荐系统出现以来,有限的数据信息就一直制约着推荐算法的进一步发展。为降低数据稀疏性的影响,增强非评分数据的利用率,基于神经网络的文本推荐模型相继被提出,但主流的卷积或循环神经网络在文本语义理解和长距离关系捕捉方面存在明... 自推荐系统出现以来,有限的数据信息就一直制约着推荐算法的进一步发展。为降低数据稀疏性的影响,增强非评分数据的利用率,基于神经网络的文本推荐模型相继被提出,但主流的卷积或循环神经网络在文本语义理解和长距离关系捕捉方面存在明显劣势。为了更好地挖掘用户与商品之间的深层潜在特征,进一步提高推荐质量,提出一种基于Ro BERTa和图增强Transformer的序列推荐(RGT)模型。引入评论文本数据,首先利用预训练的Ro BERTa模型捕获评论文本中的字词语义特征,初步建模用户的个性化兴趣,然后根据用户与商品的历史交互信息,构建具有时序特性的商品关联图注意力机制网络模型,通过图增强Transformer的方法将图模型学习到的各个商品的特征表示以序列的形式输入Transformer编码层,最后将得到的输出向量与之前捕获的语义表征以及计算得到的商品关联图的全图表征输入全连接层,以捕获用户全局的兴趣偏好,实现用户对商品的预测评分。在3组真实亚马逊公开数据集上的实验结果表明,与Deep FM、Conv MF等经典文本推荐模型相比,RGT模型在均方根误差(RMSE)和平均绝对误差(MAE)2种指标上有显著提升,相较于最优对比模型最高分别提升4.7%和5.3%。 展开更多
关键词 推荐算法 评论文本 RoBERTa模型 图注意力机制 Transformer机制
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32份居民日常使用洗手液抑菌效果分析
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作者 杨海锋 华丽 +3 位作者 王红梅 潘周舟 汪礼 裔书瑜 《工业微生物》 CAS 2024年第3期116-119,共4页
日常生活中,民众经常会用到洗手液,尤其是具有抑菌功效的洗手液产品,为保障民众的洗手效果,确保洗手液能够真正发挥抑菌功效,文章对从居民家中收集32份正在使用的洗手液产品进行监测,并参照我国现行标准GB 15979-2002溶出性抗(抑)菌产... 日常生活中,民众经常会用到洗手液,尤其是具有抑菌功效的洗手液产品,为保障民众的洗手效果,确保洗手液能够真正发挥抑菌功效,文章对从居民家中收集32份正在使用的洗手液产品进行监测,并参照我国现行标准GB 15979-2002溶出性抗(抑)菌产品抑菌性能试验方法,评估不同洗手液产品对大肠杆菌的抑制效果。测试结果表明,在8份冲水洗手液中,有6份对大肠杆菌的抑菌率>99.99%,判定其具有较强抑菌作用;在24份免洗洗手液中,有23份对大肠杆菌的抑菌率>90%,判定为具有较强抑菌作用,而剩余1份样品的抑菌率为81.8%,被判定为具有抑菌作用。因此,可以认为居民日常使用的抑菌洗手液大多都对大肠杆菌具有较好的抑制作用,可达到预期抑菌效果。 展开更多
关键词 洗手液 大肠杆菌 抑菌
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种子休眠与萌发调控的研究进展 被引量:4
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作者 宋松泉 唐翠芳 +3 位作者 雷华平 姜孝成 王伟青 程红焱 《作物学报》 CAS CSCD 北大核心 2024年第1期1-15,共15页
休眠使植物种子能够为萌发安排时间,直到环境条件变得有利于幼苗的存活与生长。种子的休眠特性具有重要的生态适应性意义和显著的农业价值。植物激素脱落酸(ABA)和赤霉素(GA)是种子休眠与萌发的关键因素,处于休眠状态的成熟种子含有高... 休眠使植物种子能够为萌发安排时间,直到环境条件变得有利于幼苗的存活与生长。种子的休眠特性具有重要的生态适应性意义和显著的农业价值。植物激素脱落酸(ABA)和赤霉素(GA)是种子休眠与萌发的关键因素,处于休眠状态的成熟种子含有高水平的ABA和低水平的GA;ABA诱导和维持种子休眠,而GA拮抗ABA的作用和促进种子萌发。萌发延迟-1 (DOG1)是种子休眠的主要调控因子,与ABA协同作用延迟萌发。DOG1通过与PP2C ABA过敏感萌发(AHG1/AHG3)结合以增强ABA的信号转导,以及抑制AHG1的作用以增加ABA的敏感性和强加种子休眠。印记基因在受精前后受到表观遗传机制的调控,与种子休眠的建立与释放密切相关。近年来,种子休眠的调控研究取得了显著的进展。本文综述了植物激素ABA和GA对种子休眠与萌发的控制, DOG1调控种子休眠的作用机制,以及种子休眠与萌发的表观遗传调控,并提出了在本领域需要进一步研究的科学问题,以期为深入理解种子休眠与萌发的分子机制、抗穗萌发育种以及促进休眠种子的萌发提供参考。 展开更多
关键词 DOG1 表观遗传 分子机制 植物激素 种子休眠
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基于CNN-SAEDN-Res的短期电力负荷预测方法 被引量:4
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作者 崔杨 朱晗 +2 位作者 王议坚 张璐 李扬 《电力自动化设备》 EI CSCD 北大核心 2024年第4期164-170,共7页
基于深度学习的序列模型难以处理混有非时序因素的负荷数据,这导致预测精度不足。提出一种基于卷积神经网络(CNN)、自注意力编码解码网络(SAEDN)和残差优化(Res)的短期电力负荷预测方法。特征提取模块由二维卷积神经网络组成,用于挖掘... 基于深度学习的序列模型难以处理混有非时序因素的负荷数据,这导致预测精度不足。提出一种基于卷积神经网络(CNN)、自注意力编码解码网络(SAEDN)和残差优化(Res)的短期电力负荷预测方法。特征提取模块由二维卷积神经网络组成,用于挖掘数据间的局部相关性,获取高维特征。初始负荷预测模块由自注意力编码解码网络和前馈神经网络构成,利用自注意力机制对高维特征进行自注意力编码,获取数据间的全局相关性,从而模型能根据数据间的耦合关系保留混有非时序因素数据中的重要信息,通过解码模块进行自注意力解码,并利用前馈神经网络回归初始负荷。引入残差机制构建负荷优化模块,生成负荷残差,优化初始负荷。算例结果表明,所提方法在预测精度和预测稳定性方面具有优势。 展开更多
关键词 短期电力负荷预测 卷积神经网络 自注意力机制 残差机制 负荷优化
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番茄钵苗移栽探出式取钵机构设计与试验 被引量:3
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作者 辛亮 王明成 +3 位作者 孙国玉 张浩 孙铭翼 王航 《农业机械学报》 EI CAS CSCD 北大核心 2024年第3期96-105,共10页
为了降低番茄钵苗移栽过程取钵机构对秧苗钵土根系的损伤,同时避免机械式钵苗移栽机构设计特殊取苗轨迹与姿态的优化难题,提出了一种可与系列移栽机构配合使用的番茄钵苗探出式取钵机构,实现取苗各关键位置机构秧针以固定角度完成探出... 为了降低番茄钵苗移栽过程取钵机构对秧苗钵土根系的损伤,同时避免机械式钵苗移栽机构设计特殊取苗轨迹与姿态的优化难题,提出了一种可与系列移栽机构配合使用的番茄钵苗探出式取钵机构,实现取苗各关键位置机构秧针以固定角度完成探出入钵、移动送苗及收回推秧工序。根据钵苗移栽取钵过程分析与设计要求,建立了探出式取钵机构力学分析模型,并获得影响秧针扎入钵土时驱动杆受最小驱动力的因素。基于Matlab App Designer平台开发了取钵机构计算机辅助分析设计软件,获得满足番茄钵苗移栽要求的取钵机构设计参数集。采用三因素五水平二次回归正交旋转中心组合试验方法,以驱动杆斜杆夹角、钵体含水率、入钵深度为试验因素,以钵体完整率和取苗成功率为评价指标,试制样机并搭建台架实施参数组合优化及验证试验,结果表明:探出式取钵机构可有效地配合取苗机构完成各项性能工作要求,在参数组合为驱动斜杆间夹角112°、钵体含水率57.5%、入钵深度28.4 mm时作业效果最佳,钵体完整率为96.44%,取苗成功率为97.06%,满足钵苗移栽作业性能。 展开更多
关键词 番茄 钵苗移栽 探出式 取钵机构 力学分析
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益生菌在鸡养殖中的应用及其作用机理 被引量:2
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作者 何彩梅 龚福明 林连兵 《中国家禽》 北大核心 2024年第3期95-103,共9页
益生菌是一种新型绿色的添加剂,能通过促生长调控、维持微生态平衡、维持肠道屏障结构和功能完整及增强免疫等机制改善鸡的健康并提高其生长性能与品质,同时也不会污染环境和发生药物残留。文章对益生菌在鸡养殖业中的应用及其作用机理... 益生菌是一种新型绿色的添加剂,能通过促生长调控、维持微生态平衡、维持肠道屏障结构和功能完整及增强免疫等机制改善鸡的健康并提高其生长性能与品质,同时也不会污染环境和发生药物残留。文章对益生菌在鸡养殖业中的应用及其作用机理进行综述,以期为鸡用益生菌的研究及应用提供理论参考。 展开更多
关键词 益生菌 鸡养殖 作用机理
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碳减排“时-空-效-益”统筹理论:Ⅲ.效率统筹 被引量:2
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作者 魏一鸣 王翔宇 +1 位作者 陈炜明 唐葆君 《北京理工大学学报(社会科学版)》 CSSCI 北大核心 2024年第5期30-38,共9页
碳减排效率表现为在达成碳减排目标同时尽可能降低社会成本,实现碳减排效率最优的关键在于统筹政府管制与市场机制。作为碳减排“时-空-效-益”统筹理论系列论文的组成部分,构建了效率统筹方法框架,首先阐释了碳减排效率的概念内涵,提... 碳减排效率表现为在达成碳减排目标同时尽可能降低社会成本,实现碳减排效率最优的关键在于统筹政府管制与市场机制。作为碳减排“时-空-效-益”统筹理论系列论文的组成部分,构建了效率统筹方法框架,首先阐释了碳减排效率的概念内涵,提出了效率统筹的理论框架;进而采用新制度经济学的理论视角,系统分析了市场机制与政府干预在碳减排过程中的互动机制与互补路径;并结合相对斜率决策准则,应用C3IAM/EcOp模型和CEEPA-CETA-FM模型深入探索了如何在不同减排机制下实现减排资源的优化配置,科学回答了碳减排混合机制的设计问题,为统筹政府管制与市场机制提供方法基础。 展开更多
关键词 碳减排效率 效率统筹 市场机制 政府管制 混合机制
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数字经济赋能乡村生态农产品价值实现的典型模式与形成机制分析 被引量:8
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作者 栾晓梅 陈池波 +2 位作者 田云 常静 黄娟 《四川农业大学学报》 CSCD 北大核心 2024年第1期224-230,共7页
【目的】生态农产品价值实现是多元化推进乡村振兴的关键举措,探索数字经济赋能乡村生态农产品价值实现的典型模式和形成机制有利于培育壮大乡村绿色发展新动能,促进和美乡村建设和农民增收。【方法】通过对全国数字化先进县的典型案例... 【目的】生态农产品价值实现是多元化推进乡村振兴的关键举措,探索数字经济赋能乡村生态农产品价值实现的典型模式和形成机制有利于培育壮大乡村绿色发展新动能,促进和美乡村建设和农民增收。【方法】通过对全国数字化先进县的典型案例进行梳理,从其关键做法,主要成效和价值体现,以及何以实现等方面系统分析数字经济赋能乡村生态农产品价值实现的典型模式和形成机制。【结果】“互联网+现代农业”融合发展、产学研合作,以及物联网与大数据技术应用是案例中数字经济赋能乡村生态农产品价值实现的3种典型模式。在此基础上,得出数字经济赋能乡村生态农产品价值实现的3条形成路径,即数字经济通过推动产业升级,为乡村生态农产品价值实现提供驱动力;数字经济通过提高乡村农产品流通效率,为乡村生态农产品价值实现创造良好的条件;数字经济通过创新商业模式,为乡村生态农产品价值实现建立有效路径。【结论】目前乡村数字经济发展仍处于较低水平,相应的政策措施和管理机制应该联合政府、企业和社会多方力量,聚焦在数字基础设施建设和人才培养等方面,推动乡村数字技术渗透的广度和深度,促进乡村生态农产品价值实现。 展开更多
关键词 生态农产品 数字经济 典型模式 机制
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寒地玉米秸秆力学特性研究 被引量:3
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作者 郭思佳 刘新柱 +5 位作者 刘向东 刘春山 邢蕾 王海祥 许健伟 王树林 《农机化研究》 北大核心 2024年第6期170-174,共5页
为了合理利用玉米秸秆这种生物质资源,采集了寒地整株玉米秸秆,结合自制试验装置,利用电子万能试验机等设备,测试了整株玉米秸秆不同直径部位在相同加载速率下有节段径向和轴向压缩及无节段抗弯的力学性能。对试验数据进行了拟合,建立... 为了合理利用玉米秸秆这种生物质资源,采集了寒地整株玉米秸秆,结合自制试验装置,利用电子万能试验机等设备,测试了整株玉米秸秆不同直径部位在相同加载速率下有节段径向和轴向压缩及无节段抗弯的力学性能。对试验数据进行了拟合,建立了相关数学模型,结果表明:当直径小于20mm时,轴向压缩实验中直径对压力影响并不明显,直径达到25mm左右时影响开始显现,直径大于29mm后影响非常显著;径向压缩时,离秸秆顶端较近的几节直径与压力近似线性相关,但随着直径的增加径向压力并不是均值上升,具有一定的离散性。抗弯试验中,在初始阶段压力在某一范围内上下波动,直径对压力影响并不显著;当直径大于23mm后,所需压力值显著增加;当直径大于30mm之后,直径对压力的影响产生了较为明显的波动性。试验数据真实可靠,拟合结果具有较强的可参考性,可为更好地开发利用秸秆资源及优化秸秆收获装置结构提供理论依据。 展开更多
关键词 玉米秸秆 力学性能 压缩 弯曲
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数字平台场域互动观的建构研究 被引量:1
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作者 舒成利 刘芳颖 +1 位作者 赵晶旭 高山行 《华东经济管理》 CSSCI 北大核心 2024年第4期59-71,共13页
文章依据社会学中的场域理论,提出“数字平台场域互动观”。研究发现,数字平台具有“场域”属性,是一种商业场域,场域理论在此具有独到的解释力;互动在数字平台中扮演核心角色,是数字平台运行的微观基础;数字平台的场域互动模式包括同... 文章依据社会学中的场域理论,提出“数字平台场域互动观”。研究发现,数字平台具有“场域”属性,是一种商业场域,场域理论在此具有独到的解释力;互动在数字平台中扮演核心角色,是数字平台运行的微观基础;数字平台的场域互动模式包括同场域互动模式、跨场域互动模式和复跨场域互动模式;数字平台的互动模式决定了其治理机制,并呈现出多样化的特点,从而要求有相对应的保障机制。文章构建了一个平台研究的系统性理论框架,为推动数字平台领域研究、数字平台健康持续发展以及政府有效精准地规制数字平台提供了新思路。 展开更多
关键词 数字平台 场域理论 互动模式 治理机制 保障机制
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