Effect of Flow Directions on Multiphase Flow Boiling Heat Transfer Enhanced by Suspending Particles in a Circulating Evaporation System

A circulating fluidized bed evaporator(including down-flow, horizontal, and up-flow beds) was constructed to study the effect of flow directions on multiphase flow boiling heat transfer. A range of experimental investigations were carried out by varying amount of added particles(0-2%), circulation flow rate(2.15-5.16 m~3/h) and heat flux(8-16 kW/m~2). The comparison of heat transfer performance in different vertical heights of the horizontal bed was also discussed. Results reveal that the glass bead particle can enhance heat transfer compared with vapor-liquid two-phase flow for all beds. At a low heat flux(q = 8 kW/m), the heat-transfer-enhancing factor of the horizontal bed is obviously greater than those of the up-flow and down-flow beds. With the increase in the amount of added particles, the heat-transfer-enhancing factors of the up-flow and down-flow beds increase, whereas that of the horizontal bed initially increases and then decreases. However, at a high heat flux(q=16 kW/m), the heat-transfer-enhancing factors of the three beds show an increasing tendency with the increase in the amount of added particles and become closer than those at a low heat flux. For all beds, the heat-transfer-enhancing factor generally increases with the circulation flow rate but decreases with the increase in heat flux.     

奥美拉唑致不良反应1例分析

我院急诊在临床应用奥美拉唑过程中遇到1例发生不良反应,经积极处理后好转,现将治疗体会介绍如下。1临床资料患者:女,36岁。因患慢性浅表性胃炎,自服奥美拉唑20mg,1次／天,当服到第2天后,突然出现全身瘙     

关于高师大学生就业能力及其培养缺陷的思考

高师大学生的就业问题值得关注,要解决其就业,关键是提高其就业能力。高师大学生的就业能力主体现在具有良好的思想素质、较高的化修养、较强的业务能力、良好的身体和心理素质、先进的教育理念、科学的就业观和良好的自我监控能力。要培养其就业能力,应突出改变现行高师教育中的缺陷,构建适应未来教师需要的知识结构和教学技能;倡导和支持学生参加教育科学研究;重视师德教育中存在的问题,并突出职业价值观和教育成功期望的培养。     

文献检索课教学课堂上的"三十六计"(连载三)

五、如何维持课堂纪律 第二十二计:防患未然 [提要]教师在课前、课上采取各种方式集中学生注意力,防止破坏课堂秩序的现象发生.     

公共体育场馆服务外包风险识别与规避机制研究

摘要：公共体育场馆服务外包是改革的趋势之一,构建服务外包风险识别与规避机制有利于减少相关风险。采用专家访谈和问卷调查法,在调查公共体育场馆服务外包项目状况的基础上,识别服务外包过程中的风险,进而构建服务外包的规避机制,研究认为：公共体育场馆服务外包项目主要有保洁、安保、绿化、设施的管理与维护等,基本上停留在日常管理业务服务外包上,而咨询、策划等高端服务项目外包还处在待开发阶段;公共体育场馆服务外包存在着有限理性风险、外包关系潜在锁定风险、逆向选择风险、道德风险、腐败风险、外包关系协调六大风险;通过建立合理的接包商选择机制、监督机制、激励机制、质量考评机制、自我保护机制、合同的弹性机制、人才培养与引进机制、“关系”管理机制八大机制对场馆的服务外包的风险进行规避。为公共体育场馆服务外包提供理论与实践依据。     

Existence and global exponential stability of equilibrium of competitive neural networks with different time scales and multiple delays

In this paper, some sufficient conditions are obtained for existence and global exponential stability of a unique equilibrium point of competitive neural networks with different time scales and multiple delays by using nonlinear Lipschitz measure (NLM) method and constructing suitable Lyapunov functional. The results of this paper are new and they complete previously known results.     

Optimal local sensor decision rule for target detection with channel fading statistics in multi-sensor networks

In this paper, we investigate the optimal local sensor decision rule based on non-ideal transmission channels between local sensors and the fusion center for distributed target detection system. The optimality of a likelihood-ratio test (LRT)-based local decision rule at local sensor, which requires only the knowledge of channel statistics instead of instantaneous channel state information (CSI), is established. The coupled local decision rule at each sensor is derived in a closed-form for coherent BPSK and OOK and non-coherent OOK. The iterative person-by-person optimization (PBPO) algorithm is employed to solve the coupled local thresholds. Simulation analysis reveals that the derived thresholds according to the local decision rule are consistent to the exhaustive searching. Furthermore, the detection performance of the system with the proposed optimal local decision rule for different reception modes and modulations is analyzed and compared.     

项目型组织成员知识转移动机实证研究—与组织情境的跨层次作用

知识是项目型组织(project-based organizations,PBOs)持续发展的关键资源,其有效地转移和共享不但有助于项目的成功,更有利于PBOs的长远发展。本研究运用多层线性模型,通过采集和分析来自中国建筑第*工程局有限公司的480个项目型组织样本问卷数据,探讨组织情景对项目型组织成员知识转移动机和知识转移效果的跨层次影响。结果表明:知识转移动机是决定知识转移行为的关键所在;组织情境差异化影响成员的知识转移动机和知识转移效果。这一发现揭示了组织情景影响成员知识动机和知识转移效果的内在机理,拓展了主流文献的相关研究,并为项目型组织知识管理实践提供借鉴。     

地区差异下居民消费对用水量的影响分析——基于门槛模型的实证研究

基于Hansen非动态面板门槛回归模型,从全国和东部、中部和西部三大区域就居民消费对用水量的门槛效应进行实证分析,结果表明:在居民收入和人力资本的作用下,居民消费对用水量的影响存在显著的门槛效应.全国层面,居民消费对用水量的弹性系数呈现先降后升的变化形态,但增幅降低;区域层面,东部居民消费对用水量的促进作用逐渐降低,西部居民消费促进用水量的增长,中部门槛检验不显著.进一步分析发现:经济发展,特别是城镇化影响门槛值和弹性系数的大小,人力资本作为门槛变量时居民消费对用水量的影响最大.     

结构调整视角下的能源效率变动与回弹效应考察——基于三次产业的实证分析

基于因素分解法对我国1986 ～2013年节能因素进行分析,并将能源效率变化中技术进步的作用进行量化,在此基础上构建能源回弹效应模型对国家层面及三次产业的能源回弹效应进行比较分析.结果表明:技术进步对能源效率的提升具有决定性作用,产业结构调整抑制了能源强度的下降,对能源效率产生负向影响,能源结构调整也有助于能源效率提升,但是效果比较微弱;我国宏观经济的能源回弹效应表现为逆反回弹效应,且呈现阶段性特征,1986～2001年为部分回弹效应,2002 ～ 2013年为逆反回弹效应,技术进步的节能效果并不理想,而且近年来发挥的作用不断弱化;能源回弹效应在三次产业间的表现形式差异较大,第一产业表现为超级节能现象,第二产业表现为强逆反回弹现象,第三产业表现为部分回弹现象.