卤化银探测器及其某些特性

文中简述了卤化银(主要是溴化银)单晶片的某些特性,氯化银单晶片与此大致相似。作为低温晶体探测器,对~(241)Am-α放射源,分辨率为17%。卤化银晶片是固体电解质,只有Ag离子对输出电信号有贡献,有显著的极化现象。在液氮槽内溴化银晶片的电导率在几个数量级内成为可控的,由在室温下外加偏置电压大小所引起的分解状态下的初始电流决定。     

形貌对ZnS微纳结构电化学电极特性影响及机制分析

在低能耗条件下以水热法实现了对ZnS材料的形貌调控,通过扫描电子显微镜及透射电子显微镜表征证明了所获得的ZnS材料为纳米颗粒、微米块和毛线球三种形貌。X射线衍射结果表明ZnS纳米颗粒及ZnS微米块为闪锌矿结构,ZnS毛线球为纤锌矿结构。以三种形貌的ZnS材料分别构建了电化学电极,以循环伏安法和交流阻抗谱对ZnS基电极的电化学特性进行了表征。结果表明,毛线球形貌的ZnS材料较大的比表面积使得以其构建的电极中电子传导速率最快,电化学特性最为优异。     

刚度和阻尼可调前桥油气悬架的设计

根据CF700型号拖拉机前桥悬架的参数要求,设计一种刚度和阻尼均可调的油气悬架系统。建立油气悬架刚度和阻尼的数学模型,计算油气弹簧的结构参数,仿真研究油气弹簧不同工作状态下的动刚度、阻尼力和输出力的特性以及各结构参数变化对油气弹簧输出力特性的影响。结果表明:油气弹簧液压缸有杆腔和无杆腔连通时阻尼力和悬架输出力较小,两腔分离时阻尼力和悬架输出力较大,通过调节两腔连通时节流面积的大小,可以调节悬架阻尼力和输出力;通过额外连通一个蓄能器,明显减小了油气弹簧的动刚度和悬架的输出力;比例阀节流孔径的大小影响悬架的阻尼力和输出力,节流孔径越大,悬架阻尼力和输出力越小。所设计的油气弹簧可以实现悬架"软"、"硬"状态的切换,并能在一定范围内对悬架刚度和阻尼进行调节。将油气悬架的刚度和阻尼系数线性化后代入振动仿真模型,得到前桥悬架拖拉机座椅安装位置垂向振动加速度均方根值、俯仰振动角加速度均方根值及前轮动载荷均方根值分别降低了9.2%、42.4%、70.3%,提高了拖拉机的行驶安全性和乘坐舒适性。该研究为后期开发半主动油气悬架提供重要理论依据。     

RL_Spider:一种自主垂直搜索引擎网络爬虫

在分析相关spider技术的基础上,提出了将强化学习技术应用到垂直搜索引擎的可控网络爬虫方法。该方法通过强化学习技术得到一些控制经验信息,根据这些信息来预测较远的回报,按照某一主题进行搜索,以使累积返回的回报值最大。将得到的网页存储、索引,用户通过搜索引擎的搜索接口,就可以得到最佳的搜索结果。对多个网站进行主题爬虫搜索,实验结果表明,该方法对于网络的查全率和查准率都具有较大的提高。     

Measure controllable volumetric mesh parameterization

Volumetric parameterization is a fundamental problem in solid and physical modeling. In practice, it is highly desirable to control the volumes of the regions of interest in the parameter domain. This work introduces a novel volumetric parameterization method, which allows users to prescribe the target volumetric measure of the input solid.Given a simply connected tetrahedral mesh with a single boundary surface, we first compute a volumetric harmonic map to parameterize the solid onto the unit solid ball; then we compute an optimal mass transportation map from the unit solid ball with the push-forward volume element induced by the harmonic map onto the parameter domain with the user prescribed volumetric measure. The composition of the volumetric harmonic map and the optimal mass transportation map gives a measure controllable volumetric parameterization. Furthermore, this method can handle solids with empty voids inside.The method has solid theoretic foundation, and is based on conventional algorithms in computational geometry, and easy to implement. The experimental results demonstrate the efficiency and efficacy of the proposed method.     

Priority load control algorithm for optimal energy management in stand-alone photovoltaic systems

In stand-alone PV System facilities no grid connection exists, therefore the solar generator and battery bank have to be carefully sized in order to supply the energy demand for a given period of time. Batteries are considered as a weak component of the system, comprising an important part of the total cost and are usually replaced one or two times during PV system lifetime. A priority load control algorithm has been developed in order to gain an optimal energy management over system loads and the battery storage, and therefore provides a better energy management efficiency and guarantee the energy supply for critical loads. This will increase the reliability of the system and the end-user satisfaction. This article describes a stand-alone PV system model used for the development of a priority load control algorithm and explains and implements the algorithm. The results of several test scenario simulations are shown and discussed.     

白象山铁矿精细化成本管控体系的构建及应用

铁矿是一种重要的矿物资源，其价格主要由市场决定。因此，在价格一定的条件下，铁矿企业要想进一步提高经济效益，提高市场竞争力，主要通过降低成本的途径来实现。以白象山铁矿为例，为实现白象山铁矿原矿成本控制，主要从技术创新和生产管理出发，通过采用防治水技术优化、采用安全高效采矿工艺、分级支护、大数据精准充填、自动化技术攻关、生产管理降本、财务收支管理降本、技术管理降本、增加零星工程自营等多种方法来降低成本。精细化成本管控体系不仅为该矿创造了巨大的经济效益，而且可为其他类似条件的矿山提供借鉴。     

Parallel concatenated convolutional codes from linear systems theory viewpoint

The aim of this work is to characterize two models of concatenated convolutional codes based on the theory of linear systems. The problem we consider can be viewed as the study of composite linear system from the classical control theory or as the interconnection from the behavioral system viewpoint. In this paper we provide an input–state–output representation of both models and introduce some conditions for such representations to be both controllable and observable. We also introduce a lower bound on their free distances and the column distances.     

Profiled rotary dresser with controlled size and distribution of abrasive grits: Performance assessment

This paper reports on a novel proprietary profiled rotary dresser which, in contrast with conventional tools, enables a controlled arrangement of geometrically defined abrasives over complex profiles. Output forces and abrasives’ wear were investigated during dressing and grinding tests. This showed a significant reduction in radial dressing forces (˜37%) and volumetric loss of material per grit (˜21%) when compared with conventional tools, together with low grinding forces and workpiece surface roughness variability for different wear conditions. The novel dresser proves the ability to obtain uniform wear rates along complex profiles, while allowing abrasive segment replacement to restore the dressing conditions.     

矿井多级机站可控式通风系统的研究与实践

本文对矿井多级机站可控式通风系统研究工作作总结，并列举了工业应用情况，说明多级机站可控式通风技术是一种节能、易于风量痫节等特点的新技术。