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二元母猪场几个生产技术问题
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作者 曲乃昌 催雅茹 +6 位作者 林荫海 陈鸿鹏 杨志 王林 张凤山 郭英全 程光远 《黑龙江畜牧兽医》 CAS 北大核心 2000年第4期41-41,共1页
关键词 二元母猪 种公猪 饲养管理 猪舍环境
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二元树上的无规则性定理 被引量:1
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作者 赵静 魏杰 《河北工业大学学报》 CAS 2003年第4期103-107,共5页
概率论中无规则性概念的基本思想是,在二值等可能Bemoulli序列中,0和1的出现是无规则的,而且想要通过选择来控制它稍偏多于0或1也是不可能的.本文的目的是要建立二元树上的一类与Markov链场有关的极限定理,其中包含无规则性概念的推广.
关键词 无规则性 选择函数 二元树上的马尔可夫随机
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Comparative analysis of isothermal and non-isothermal solidification of binary alloys using phase-field model 被引量:2
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作者 肖荣振 安国升 +2 位作者 朱昶胜 王智平 杨世银 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3639-3644,共6页
Based on the entropy function, a two-dimensional phase field model of binary alloys was established. Meanwhile, an explicit difference method with uniform grid was adopted to solve the phase field and solute field con... Based on the entropy function, a two-dimensional phase field model of binary alloys was established. Meanwhile, an explicit difference method with uniform grid was adopted to solve the phase field and solute field controlled equations. And the alternating direction implicit(ADI) algorithm for solving temperature field controlled equation was also employed to avoid the restriction of time step. Some characteristics of the Ni-Cu alloy were captured in the process of non-isothermal solidification, and the comparative analysis of the isothermal and the non-isothermal solidification was investigated. The simulation results indicate that the non-isothermal model is favorable to simulate the real solidification process of binary alloys, and when the thermal diffusivity decreases, the non-isothermal phase-field model is gradually consistent with the isothermal phase-field model. 展开更多
关键词 phase-field model binary alloys isothermal solidification non-isothermal solidification
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规模二元母猪场圈舍空气质量对比试验 被引量:1
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作者 郭继柱 王滨 +1 位作者 张新萍 董琴 《黑龙江畜牧兽医(下半月)》 北大核心 2015年第12期70-71,共2页
为了对新疆生产建设兵团第十三师标准化规模猪场圈舍设计提供科学理论依据,笔者对猪场圈舍的内环境进行综合评价,测定圈舍内空气温度、湿度、NH3浓度、细菌总数和粉尘含量,同时与中、小型集约化养猪场环境参数及管理标准GB/T17824.4—19... 为了对新疆生产建设兵团第十三师标准化规模猪场圈舍设计提供科学理论依据,笔者对猪场圈舍的内环境进行综合评价,测定圈舍内空气温度、湿度、NH3浓度、细菌总数和粉尘含量,同时与中、小型集约化养猪场环境参数及管理标准GB/T17824.4—1999(简称"国标")中有关空气指标要求进行对比分析。结果表明:标准化猪舍(试验组)较传统猪舍(对照组)温度、湿度更符合规模猪场猪只的生理需求;试验组、对照组圈舍NH3浓度均符合国标要求,细菌总数和粉尘含量均超出国标要求。说明在气候干燥、地域偏远、风沙天气较多的独特地理气候条件下,标准化规模猪场圈舍设计需要进行综合考虑,着重解决空气质量问题。 展开更多
关键词 规模二元母猪 圈舍 空气质量 对比测定 试验
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浅谈元极科研
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作者 李荣镜 《人天科学研究》 1996年第5期1-3,共3页
为了促进元极科研的进一步开展,建议运用现代先进科技手段,对十月胎音、三元能量、三元场进行多角度、长时期的测试、记录,由此进行理论研究,为三元能量广泛应用于各领域开辟道路。
关键词 十月胎音 三元能量 二元场 现代科学
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Morphological evolution and growth kinetics of Kirkendall voids in binary alloy system during deformation process-Phase field crystal simulation study 被引量:2
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作者 Wen-jing MA Chang-bo KE +2 位作者 Shui-bao LIANG Min-bo ZHOU Xin-ping ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第3期599-607,共9页
The formation and growth of Kirkendall voids in a binary alloy system during deformation process were investigated byphase field crystal model.The simulation results show that Kirkendall voids nucleate preferentially ... The formation and growth of Kirkendall voids in a binary alloy system during deformation process were investigated byphase field crystal model.The simulation results show that Kirkendall voids nucleate preferentially at the interface,and the averagesize of the voids increases with both the time and strain rate.There is an obvious coalescence of the voids at a large strain rate whenthe deformation is applied along the interface under both constant and cyclic strain rate conditions.For the cyclic strain rate appliedalong the interface,the growth exponent of Kirkendall voids increases with increasing the strain rate when the strain rate is largerthan1.0×10-6,while it increases initially and then decreases when the strain rate is smaller than9.0×10?7.The growth exponent ofKirkendall voids increases initially and then decreases gradually with increasing the length of cyclic period under a square-waveform constant strain rate. 展开更多
关键词 Kirkendall void binary alloy phase field crystal method growth exponent DEFORMATION
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Phase-field simulation of lamellar growth for a binary eutectic alloy 被引量:1
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作者 李新中 刘冬梅 +3 位作者 孙涛 苏彦庆 郭景杰 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期302-307,共6页
Using general multi-phase-field model,detailed microstructures corresponding to different initial lamellar sets were simulated in a binary eutectic alloy with an asymmetric phase diagram.The simulation results show th... Using general multi-phase-field model,detailed microstructures corresponding to different initial lamellar sets were simulated in a binary eutectic alloy with an asymmetric phase diagram.The simulation results show that regular or unstable oscillating lamellar structures depend on the initial lamellar widths of two solid phases.A lamellar morphology map associating with the initial widths has been derived,which is capable of showing the condition of forming various lamella structures.For instance,a regular lamella was formed with fast solidification while large lamella resulted from disorder growth with low interfacial velocity. The investigated interface velocities indicate that with fast solidification to form regular lamella,a disorder growth manner or a large lamellar spacing causes a low interface velocity.These results are in good agreement with those proposed by Jackson-Hunt model. 展开更多
关键词 phase-field simulation microstructure eutectic lamella
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Recovery of Foreign Interest Rates from Exchange Binary Options 被引量:1
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作者 M. Mitsuhiro Y. Ota 《Computer Technology and Application》 2015年第2期76-88,共13页
One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scho... One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scholes model and recovers the real drift of binary call options from their market prices. For space-dependent real drift, we obtain stable linearization and an integral equation. We also find that using market prices of options with different strike prices enables us to identify the term structure of the real drift. Results demonstrate that our new approach can confirm the existence of arbitrage opportunities in a binary option transaction. 展开更多
关键词 Inverse problem binary option real drift arbitrage opportunities Black-Scholes model.
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Prevention of rockburst by guide holes based on numerical simulations 被引量:6
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作者 ZHU Qi-hu LU Wen-bo +2 位作者 SUN Jin-shan LUO Yi CHEN Ming 《Mining Science and Technology》 EI CAS 2009年第3期346-351,共6页
We studied variations in the stress field around guide holes drilled during tunnel excavation to understand the mechanical mechanism by which these holes help prevent rockburst.The study used elasto-plastic analysis o... We studied variations in the stress field around guide holes drilled during tunnel excavation to understand the mechanical mechanism by which these holes help prevent rockburst.The study used elasto-plastic analysis of a circular chamber under non-axisymmetrical loads.The results showed that the unloading of in-situ stresses, and the forming of a secondary stress field, leads to a severe change in the stress field around the guide holes.This causes the formation of an X-shaped area of plastic deformation, which prevents the rockburst.Adopting a sub-model finite element technique, we analyzed the factors that influence the distribution of the plastic area, such as the guide hole distribution and the in-situ stress state.The calculations showed that higher initial stresses result in greater adjustment to the stress field.When the stress concentration is greater the size of the plastic area surrounding the guide hole is larger.A multi-row distribution of the guide holes shaped like a quincunx can increase the interconnectivity of the plastic areas and allow the plastic area to extend from the tunnel wall deep into the surrounding rock.An optimized design was put forward based on the distribution of the plastic area around guide holes and the factors that influence it. 展开更多
关键词 ROCKBURST guide hole shear failure finite element method sub-model
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我国研制成功光学成像新系统
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《广东科技》 2002年第9期64-64,共1页
我国科学家近日研制出了一套具有大视角、免对焦等先进功能的新型光学成像系统。这项名为“二元光学半球视场成像技术”的新成果原理与常规的光学系统成像原理不同,它将二元光学与半球成像系统结合,获得大视场凝视,不仅结构更加轻巧... 我国科学家近日研制出了一套具有大视角、免对焦等先进功能的新型光学成像系统。这项名为“二元光学半球视场成像技术”的新成果原理与常规的光学系统成像原理不同,它将二元光学与半球成像系统结合,获得大视场凝视,不仅结构更加轻巧,而且不用调焦就能获得清晰图像。这一系统在空间光学、海洋光学等领域应用时,无需转动部件即可获得水平视场达170度的图像,并可自动消除大气、海水等因素造成的环境干扰,获得精确的目标捕获。 展开更多
关键词 光学成像系统 二元光学半球视成像技术 应用 空间光学 海洋光学
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Market Analysis of Typical Products in Italy: Bivariate Statistical Relationships Between Qualitative Variables
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作者 Lanfranchi Maurizio Giannetto Carlo Zirilli Agata Alibrandi Angela 《Chinese Business Review》 2012年第1期65-74,共10页
The denominations of origin being perceived by the consumers in terms of both intrinsic qualities and of extrinsic qualities, have contributed in no uncertain manner to the increase of the typical products in question... The denominations of origin being perceived by the consumers in terms of both intrinsic qualities and of extrinsic qualities, have contributed in no uncertain manner to the increase of the typical products in question, positively influenced also by the noted emergencies coming from verified alimentary alarms during the beginning of the XXI century. The objective of this paper, is to determine the habits of purchase of typical and traditional products of the people of Messina (Sicily, Italy). To do this a "motivational" survey was carried out by traditional methodology of descriptive researches. The adopted methodology of research was quantitative and random. The random research strives to identify the factors that depend on the behaviour of purchase and the appraisal of the existing relationships of cause-effect in a determined population. The interviewed were given a questionnaire composed of 17 questions on their knowledge of the typical products characteristics, the frequency of consumption, the monthly amounts destined to the purchase, the motivations that push them to the purchase of typical products rather than pre-packed. Methodologically, our statistical analysis has been performed using the log-likelihood ratio test in order to investigate the existence of association between the joint distributions of qualitative measured variables. 展开更多
关键词 typical products market analysis statistical analysis log-likelihood ratio test
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晶体相场法研究Kirkendall效应诱发的相界空洞的形成和演变 被引量:2
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作者 卢艳丽 卢广明 +2 位作者 胡婷婷 杨涛 陈铮 《金属学报》 SCIE EI CAS CSCD 北大核心 2015年第7期866-872,共7页
采用二元晶体相场模型研究了Kirkendall效应诱发的相界空洞的形成及扩展过程.模拟结果表明:对于取向差角较小的相界,空洞向原子迁移率高的一侧(a相)方向移动,空洞的形状由最初的平行四边形向六边形演化,空洞周围原子湮没速率大于产生速... 采用二元晶体相场模型研究了Kirkendall效应诱发的相界空洞的形成及扩展过程.模拟结果表明:对于取向差角较小的相界,空洞向原子迁移率高的一侧(a相)方向移动,空洞的形状由最初的平行四边形向六边形演化,空洞周围原子湮没速率大于产生速率,从而造成空洞扩大,空洞扩展过程中伴有相界的移动及相的长大和缩小.对于取向差角较大的相界,空洞还会沿相界方向扩展,使得空洞连通,将相界割裂开,割裂后的两侧相界呈现锯齿状.扩散过程中,体系的自由能逐渐降低.对于取向差角较小的相界,原子迁移率差值增大,自由能下降无明显差异.对于取向差角较大的相界,原子迁移率相差越大,自由能下降速率越快.随着相界取向差角的增大,自由能的下降速率逐渐增大.相界空洞的模拟结果与实验观察一致. 展开更多
关键词 二元晶体相模型 Kirkendall效应 相界 空位 Kirkendall空洞
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