基于STM32的农业大棚监测与控制系统

随着大数据处理、云计算、物联网、人工智能等技术的逐渐成熟,智能控制成为优化生产、解决劳动力成本攀升问题的有效方式之一.此外,智能控制还有重用性、高端制造等特性,这些特性共同促成其在众多领域得到应用,其中就包括在智慧农业上的应用. 本设计是智能控制在农业大棚具体实现,是基于单片机和GPRS网络的农业控制系统.功能主要有:采集大棚内温湿度、风机和加热器状态、TFT彩屏显示空气温湿度和加热器状态,风机、加热器、卷帘门开关状态现场可控,GPRS上传空气温湿度和风机、加热器、卷帘门开关状态给远程服务器,打开或关闭开关,服务器数据库数据存储,自动控制参数设置等.由以上功能组合实现了一套远程监控、智能控制系统.     

触摸、光线双控多点高亮LED台灯的研究

采用光敏电阻、三级管、可控硅、等器件实现对家用高亮LED台灯光照强度智能感知和对启动开关的智能控制,以低成本完成既定功能,同时对LED节能优势方面作了大量的研究。     

10kV配网设备安装调试技术探究

10 kV配电网是电力系统的重要组成部分,承担着电能的输送、交换和分配,其配电设备安装质量的好坏直接影响着供电质量。文章首先分析了安装之前的准备工作,其次对配网中的真空断路器、变压器、电缆和隔离开关等安装和调试技术进行了分析探讨。     

10 kV配网设备安装调试技术探究

10 kV配电网是电力系统的重要组成部分,承担着电能的输送、交换和分配,其配电设备安装质量的好坏直接影响着供电质量。文章首先分析了安装之前的准备工作,其次对配网中的真空断路器、变压器、电缆和隔离开关等安装和调试技术进行了分析探讨。     

音乐发光电源开关

开关是最常用的电气控制元件,普通开关功能单一。本文介绍的音乐发光开关除具有普通开关的功能外,还具有发光指示及音乐提示功能,当你闭合开关的同时,你能欣赏到一首甜美的乐曲,给你一种轻松舒适的感觉。电路结构十分简单,制作调试容易,成本低廉,适于小型企业或个体企业作产品生产。 电路原理见图。交流电压的半个周期在二极管VD_3～VD_5上有约2.1V的电压降,此电压经电容C_1滤波,LED_1稳压后(VD_3～VD_5本身亦具稳压功能),成为较平滑的直流电,供IC音乐电路工作用,音乐信号自③脚输出推动压电陶瓷片HTD放音;IC的②脚为触发端,高电平有效,为了克服通电时IC连续放     

对ZCS PWM DC/DC移相全桥变换器的简要分析

随着电力电子技术的发展,对直流变换器的要求越来越高,尤其在高压大功率场合.为了提高DC/DC变换器的效率,现在广泛采用软开关技术,尤其采用ZCS技术较多.本文在基本的移相全桥ZCS PWM变换器基本原理的基础上进行了改进,并分析在副边采用辅助电路的工作原理和实验测试.本文在移相全桥ZCS PWM变换器基本原理的基础上,在副边采用了一个辅助电路,实现了所有主开关和辅助开关的ZCS.论述了该变换器的工作时序和工作状态.在拓扑结构基础上,调试出一台样机,并列出了实验波形.     

浅谈黑河塘电站2号机组出口隔离开关B相烧毁的原因及预防

文章通过对黑河塘电站2号机组出口隔离开关B相被烧坏的事故处理以及刀闸被烧的原因分析和处理,提出了预防措施。不仅为解决黑河塘电站本次事故起到了指导作用,也对行业中同类开工的调试投产和检修运行工作有一定借鉴作用。     

一二次融合断路器在配网中的应用

为适应一次设备数字化、集成化、标准化、模块化应用发展方向,提高其智能感知、智能、智能控制能力,提出一种一二次完全融合的高压智能开关设计方案.利用内置位置传感器、SF6气敏、电流传感器等多源智能传感元件,在机箱及汇控箱上设置智能控制模块,实现了设备状态自感知、二次回路的智能化,有效提高了断路器的智能化程度.     

一二次融合断路器在配网中的应用

为适应一次设备数字化、集成化、标准化、模块化应用发展方向,提高其智能感知、智能、智能控制能力,提出一种一二次完全融合的高压智能开关设计方案.利用内置位置传感器、SF6气敏、电流传感器等多源智能传感元件,在机箱及汇控箱上设置智能控制模块,实现了设备状态自感知、二次回路的智能化,有效提高了断路器的智能化程度.     

一二次融合断路器在配网中的应用

为适应一次设备数字化、集成化、标准化、模块化应用发展方向,提高其智能感知、智能、智能控制能力,提出一种一二次完全融合的高压智能开关设计方案.利用内置位置传感器、SF6气敏、电流传感器等多源智能传感元件,在机箱及汇控箱上设置智能控制模块,实现了设备状态自感知、二次回路的智能化,有效提高了断路器的智能化程度.     

Incumplimiento del salario mínimo en Europa central y oriental

En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.     

Value at Risk in the Suburbs: Eminent Domain and the Geographical Politics of the US Foreclosure Crisis

Several US counties and local governments have recently considered a novel solution to the foreclosure crisis. They plan to use eminent domain to compel the owners of mortgage debt—and specifically of private‐label mortgage‐backed securities—to sell the debt to the government at a price reflecting the loan's market value. The government would then restructure the debt and resell it to new investors. The plans are striking because—in contrast to both development‐driven eminent domain and the federal subprime bank bailout—they would force investors to assume asset devaluation and increased long‐term risk. Notably, the plans have emerged as an instance of financialization‐focused politics in suburbs and suburban cities of color, specifically majority‐black and ‐Latino/a suburbs. Local support for the plans, we argue, is rooted in the long‐term disinvestment of these ‘suburbs of exception', which became targets of subprime lending and eventually sites where the ‘financial exception' has been localized. But these demographic shifts, fragmentation and fiscal pressures have at the same time created a suburban political terrain in which the plans have gained their strongest political support.     

Towards a Theory of Serendipity: A Systematic Review and Conceptualization

Serendipity – the notion of making surprising and valuable discoveries – plays a major role in the success of individuals and organizations alike. Previous research has established the importance of serendipity and identified important individual- and organizational-level antecedents. However, the literature has been dispersed and the boundaries of the concept have been blurry, leading to a lack of conceptual clarity and structure, and thus limiting validity and managerial actionability. Based on a systematic literature review, I synthesize existing management-related research on serendipity and explicate the emergence and composition of serendipity in the organizational context. I first identify three necessary conditions that differentiate serendipity from related concepts such as luck or targeted innovation: agency, surprise, and value. Then, I draw from the literature on sensemaking, event-based theorizing, and quantum-based approaches to management to conceptualize the process of cultivating serendipity in the organizational context as a process of enabling potentiality and materialization, and develop a multi-level theory of (cultivating) serendipity. This conceptualization contributes to our collective understanding of how, why, and when (i.e., under what conditions) organizations can leverage the value in the unexpected, which opens up fruitful avenues for further research.     

Accountability of NGOs in Bangladesh A critical overview

NGOs in Bangladesh have been recognized as effective change agents in the socio-economic arena throughout the world. Their contributions in micro credit, non-formal education and primary health care are widely known. NGOs play a significant role in society. NGO accountability, as a result, has become a critical issue. NGO accountability in Bangladesh has been examined here in relation to patrons, clients and themselves. Of the three relationships only accountability to patrons is in a near satisfactory state. Accountability to clients is handicapped by lack of opportunities of beneficiaries to participate meaningfully in NGO policy making. Accountability to themselves is adversely affected due to the adherence to a strictly hierarchical system and the influence of founding and charismatic NGO leaders.     

Cultural Economy Planning in Creative Cities: Discourse and Practice

While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.     

Input/output ranges and performance: an examination of US machine tool producers

Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.     

Sixty years of discrimination and diversity research in human resource management: A review with suggestions for future research directions

This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.     

Towards an Asian model of human resource management? A comparative analysis of China,Japan and South Korea

There has been much discussion regarding the possible decline and weakening of national systems of human resource management (HRM). Yet, culture and institutions are often cited as the major stumbling blocks to this outcome. Such constraints may dissipate in the analysis, particularly if ‘regional clusters’ are considered where geographic and cultural closeness and ‘openness’ to similar economic pressures exist. In such cases, it might be postulated that convergence in HRM will occur. We argue that China, Japan and South Korea represent such a cluster. This article examines these countries, to see if a degree of convergence is taking place and if it is towards an identifiable ‘Asian’ model of HRM. A model of change is presented that distinguishes between levels of occurrence and acceptance. Details of the development and practice of HRM in each country are then set out. The article ends with a discussion and implications section and a brief conclusion.     

The Early History of the Cumulants and the Gram-Charlier Series

The early history of the Gram-Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev-Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.     

Capturing the Implications of Services Trade Liberalization

This paper evaluates the impact of service sector trade liberalization on the world economy by a ten-region, eleven-sector CGE model with import embodied technology transfer from developed countries to developing countries. Simulation results show that service sector trade liberalization not only directly affects world service production and trade, but also has significant implications for other sectors in the economy. The major channel of the impact is through inter-industry input-output relations and TFP growth induced from services imported by developing countries from developed countries, which may be embodied with new information and advanced technology.