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天然气储气井泄漏伤害定量计算及风险评估

化工管理 2024年第7期 86-90页

作者：陈虹燕于永政王智立江苏安全技术职业学院江苏徐州221004

天然气储气井是高压储气设施,为天然气储备和调峰提供了重要的支撑作用。因其运行环境特殊,在高压低温环境下,其附件和本体会产生点蚀、氢脆、腐蚀、磨损的可能性较大,具有一定的危险性。文章针对加气站真实工况中点蚀形成的小孔径泄漏... 详细信息

天然气储气井是高压储气设施,为天然气储备和调峰提供了重要的支撑作用。因其运行环境特殊,在高压低温环境下,其附件和本体会产生点蚀、氢脆、腐蚀、磨损的可能性较大,具有一定的危险性。文章针对加气站真实工况中点蚀形成的小孔径泄漏和外力冲击形成的大孔径泄漏进行预设,直径分别为2 mm和20 mm,并针对不同泄漏孔径进行了泄漏量的计算,应用喷射火模型和蒸气云爆炸模型进行数值计算对比,用数值模拟软件模拟蒸气云爆炸前汽云扩散状态图,并为加气站安全管理、消防及安全疏散提供建议。

关键词：天然气蒸气云爆炸定量评价风险分析

An Application of Context Middleware Based on Fuzzy Logic for Wireless Sensor Networks

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Wireless Sensor Network 2009年第5期1卷 365-369页

作者： Ye NING Ruchuan wang Shouming MA zhili wang 不详

The research of context-aware computing based on wireless sensor network (WSN) aims at intelligently connecting computers, users, and environment. So its application system should be flexibly adaptable to dynamic changes of context and application requirements and proactively provides the information satisfied with current context for users. The middleware can be very effective to provide the support runtime services for context-aware computing. In this paper we propose middleware architecture for context processing. This architecture is based on fuzzy logic control (FLC) system for context reasoning and sensor fusion. We propose a formal context representation model in which a user’s context is described by a set of roles and relations correspond to a context space. A middleware prototype has been developed, which detect tourist’ physical context and provide reminding. The experiments prove that the model and approach proposed are feasible.

关键词： WSN Context-Aware Middleware FLC Pervasive Computing

超声联合超声造影对乳腺病变的诊断效能及影响因素

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中国医学影像学杂志 2024年第1期32卷 67-72页

作者：付乃芹李俊康姜莹李诗雨牛瑞兰王知力解放军总医院第一医学中心超声诊断科北京100853

目的探究超声联合超声造影(CEUS)对乳腺病变的诊断效能,分析诊断准确度的影响因素。资料与方法回顾性收集2022年1月—2023年2月在解放军总医院第一医学中心行乳腺超声、CEUS检查并有明确病理结果的784例患者的临床资料和超声图像。分析... 详细信息

目的探究超声联合超声造影(CEUS)对乳腺病变的诊断效能,分析诊断准确度的影响因素。资料与方法回顾性收集2022年1月—2023年2月在解放军总医院第一医学中心行乳腺超声、CEUS检查并有明确病理结果的784例患者的临床资料和超声图像。分析超声、CEUS对乳腺病变良恶性的诊断效能,使用Logistic回归分析诊断错误的独立危险因素。结果超声联合CEUS对乳腺病变良恶性诊断的敏感度、特异度和准确度分别为89.2%、84.4%和88.7%,曲线下面积为0.932。多因素分析结果显示:病变表现为非肿块型(OR=1.927,P=0.047)、囊实混合性(OR=3.729,P=0.000)、超声造影高增强(OR=1.937,P=0.023)时诊断错误率高,>1.0 cm病变(OR=0.688,P=0.004)及常规超声探及可疑淋巴结的病变(OR=0.143,P=0.011)时诊断错误率低。结论乳腺病变表现为非肿块型,囊实混合性及CEUS高增强时超声联合CEUS诊断错误率较高,需要进一步探索不同病变的增强模式。

关键词：乳腺疾病超声检查超声造影诊断鉴别因素分析统计学

Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis

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Journal of Forestry Research 2024年第3期35卷 155-165页

作者： Yanjun wang Guangze Jin zhili Liu Center for Ecological Research Northeast Forestry UniversityHarbin 150040People's Republic of China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040People's Republic of China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin 150040People's Republic of China

Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.

关键词： Tree size Organ age(or root order) Carbon(C) Nitrogen(N) Phosphorus(P) Pinus koraiensis

唐山市刺参(Apostichopus japonicus)养殖情况和主要病害防治

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河北渔业 2024年第6期 31-36页

作者：王志丽岳强刘志强王广宇刘建朝唐山市水产技术推广站河北唐山063000 唐山市曹妃甸区农业农村局河北唐山063299

刺参(Apostichopus japonicus)是唐山市重要的水产养殖品种,2022年养殖面积已超过5100 hm2,年产量超过7700 t。本文基于唐山地区多年的刺参苗种繁育和成参养殖的实践经验,总结了几种唐山地区常见的高温、细菌性疾病、霉菌病、寄生虫病... 详细信息

刺参(Apostichopus japonicus)是唐山市重要的水产养殖品种,2022年养殖面积已超过5100 hm2,年产量超过7700 t。本文基于唐山地区多年的刺参苗种繁育和成参养殖的实践经验,总结了几种唐山地区常见的高温、细菌性疾病、霉菌病、寄生虫病的预防和治疗措施。

关键词：唐山市刺参(Apostichopus japonicus) 病害防治

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China fertility report,2006-2016 An analysis based on China fertility survey 2017

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China Population and Development Studies 2019年第2期2卷 430-439页

作者： Dan He Xuying Zhang Ya’er Zhuang zhili wang Yu Jiang China Population and Development Research Center Beijing 100081China Renmin University of China Beijing 100872China

Based on China fertility survey 2017,this report presents the national fertility level,age-specific fertility rate and parity distribution.The survey results show that during 2006-2016 the mean ages at first marriage and first birth increased by 2.7 and 2.6 years respectively.From 2006 to 2011,the total fertility rate was around 1.60-1.70,and experienced notable fluctuations during 2012-2016.Compared the age-specific fertility in 2006 with in 2011,the curve in 2016 shifted significantly to the right side.Affected by the relaxation of the fertility policy,the proportion of second births among the total births had increased year by year since 2012.

关键词： China fertility survey Total fertility rate Age-specific fertility Parity distribution

China Family Development Report(2015)

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China Population and Development Studies 2017年第1期1卷 98-115页

作者： Hongyan LIU Yaer ZHUANG Ying LIANG Weiming GUO zhili wang Hui wang Haidong wang Fei CAI China Population and Development Research Center Beijing China

Introduction The family is the most basic unit of society and its development provides important support and impetus to social advances.China has the largest population in the world and the greatest number of families,whose sizes,structures and types are becoming increasingly diverse and complex,keeping pace with ever-changing external circumstances.

关键词： becoming sizes advances

China fertility survey 2017:design and implementation

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China Population and Development Studies 2019年第1期2卷 259-271页

作者： Yaer Zhuang Shenghui Yang Jianan Qi Bohua Li Xueqing Zhao zhili wang China Population and Development Research Center BeijingChina Renmin University of China BeijingChina

This paper examines the design and the process used to carry out the China Fertility Survey 2017,a national representative survey that collected data on fertility desire,childbearing behavior,the use of childbearing services,and the determinants of childbearing behavior.The sampling method adopted was three-stage stratified probabilities proportional to size(PPS),and survey implementation made use of Computer Assisted Personal Interviewing(CAPI).CAPI played a significant role in survey design,last-stage sampling,interviewer training,face-to-face interviews,and questionnaire review and quality control.The survey results were compared with relevant data in the Integrated Management Information System for Population and Family Planning to check consistency.Ex post facto weighting was applied to correct sample structure bias.The process used to acquire accurate personal information is summarized.Suggestions based on consideration of sampling frame distortion by population mobility and other factors are put forward in the hope of improving similar sampling surveys in the future.

关键词： Fertility survey Quality control Ex post facto weighting

Controllable image generation based on causal representation learning

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Frontiers of Information Technology & Electronic Engineering 2024年第1期25卷 135-148页

作者： Shanshan HUANG Yuanhao wang zhili GONG Jun LIAO Shu wang Li LIU School of Big Data and Software Engineering Chongqing UniversityChongqing 401331China School of Materials and Energy Southwest UniversityChongqing 400715China

Artificial intelligence generated content(AIGC)has emerged as an indispensable tool for producing large-scale content in various forms,such as images,thanks to the significant role that AI plays in imitation and production.However,interpretability and controllability remain challenges.Existing AI methods often face challenges in producing images that are both flexible and controllable while considering causal relationships within the images.To address this issue,we have developed a novel method for causal controllable image generation(CCIG)that combines causal representation learning with bi-directional generative adversarial networks(GANs).This approach enables humans to control image attributes while considering the rationality and interpretability of the generated images and also allows for the generation of counterfactual images.The key of our approach,CCIG,lies in the use of a causal structure learning module to learn the causal relationships between image attributes and joint optimization with the encoder,generator,and joint discriminator in the image generation module.By doing so,we can learn causal representations in image’s latent space and use causal intervention operations to control image generation.We conduct extensive experiments on a real-world dataset,CelebA.The experimental results illustrate the effectiveness of CCIG.

关键词： Image generation Controllable image editing Causal structure learning Causal representation learning