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A typical photovoltaic grid-connection power system usually consists of multi-stage converters to perform multiple functions simultaneously. To simplify system configuration, reduce cost and improve conversion efficiency, this paper aims to develop a buck–boost-type inverter. The proposed inverter has both step-up and step-down functions, so that it is suitable for applications with wide voltage variation. As only one power switch operates with high frequency at one time, switching losses can significantly be reduced.

A step-up/down inverter is developed by adopting a buck-interleaved buck–boost (BuIBB) DC-DC converter and connecting with an H-bridge unfolding circuit with line-commutated operation.

The proposed circuit can work functionally as either a buck-type or boost-type inverter, so that partial energy can be directly delivered to output to improve efficiency. The input current is shared by two inductors, leading to the reduction of current stresses.

To apply the proposed inverter to micro-inverter applications in the future, developing a step-up/down inverter with a higher conversion ratio will be considered.

A laboratory prototype is built accordingly to verify the feasibility of the proposed inverter. The experimental results are presented to show the effectiveness.

This paper proposes a step-up/down inverter by using the BuIBB converter, which is innovatively studied.

Traditionally, industrial power supplies have been exclusively controlled through analog control to sustain high reliability with low cost. However, with the perpetual decrement in cost of digital controllers, the feasibility of a digitally controlled switch mode power supply has elevated significantly. This paper aims to outline the challenges related to the design of digital proportional-integral (PI) controlled synchronous rectifier (SR) buck converter by comparing controller performance in continuous and discrete time. The trapezoidal approximation-based digital PI control is designed for low voltage and high-frequency SR buck converter operating under continuous conduction mode.

The analog and digital controller are designed using a SISO tool of MATLAB. Here, zero-order hold transform is used to convert the transfer function from continuous to discrete time. Frequency and time domain analysis of continuous plant, discrete plant and close loop system is performed. The designed digital PI control is simulated in MATLAB Simulink. The simulated results is also verified on hardware designed around digital signal processing control.

The continuous and discrete control loops are validated with multiple tests in the time and frequency domain. The detailed steady state theoretical analysis and performance of the SR buck converter is presented and verified by simulation. It is found that the delay in digital control loop results in a low phase margin. This phase margin decreases with higher bandwidth. The hardware experiments with the digital control loop are carried out on a 10 W prototype. The chosen parameters for the SR buck converter are found to be optimum for steady and transient state response.

This paper compares the digital and analog control approach of compensator design. It focuses on the implications created at the time of transforming the control design from continuous to discrete time. Further, it also focuses on the selection of parameters such as phase margin, bandwidth and low pass filter.

The purpose of this paper is to provide young communication managers with a theoretical framework to better understand what they are doing.

The paper combines theoretical reflections with empirical material from an observation study, a “shadowing study” of eight communication managers in German companies undertaken by the author.

Communication management is explained as a second‐order management function, i.e. a function which not only coordinates organizational performance by planning, organizing, controlling, but also institutionalizes certain concerns in the organization. Drawing on the shadowing study, the paper describes how communication managers “manage the management of others” by acting in certain roles, e.g. the missionary (not the guru), the agent of common sense (not the enforcer), the buck's stop (not the CEO's darling). Communication management, it is argued, is not predominantly concerned with power in the organizations, but with influence.

Based on week‐long observations of eight experienced communication executives' everyday activities, the paper argues against concepts which implicitly or explicitly debase “soft”, “influence‐based” and “people‐oriented” approaches and portray “proper” communication management as “hard”, “power‐based” and “system‐oriented”.

The purpose of this study is to show in power-voltage curve, a unique maximum power point (MPP) is existed which has the maximum power.

This paper presents a MPP tracker algorithm for a standalone system includes DC-DC buck converter and battery storage.

By using this algorithm, the maximum available power is achieved and simultaneously, the battery is charged and also protected against overcharge and discharge. The operation of the proposed algorithm is evaluated in with Proteus software to be sure that it can be implemented in microcontroller in reality.

The simulations results show that the proposed algorithm is able to detect the MPP under different irradiations. Moreover, the battery is charged during the day by PV and protected against overcharge and discharge.

With this number the Library Review enters on its ninth year, and we send greetings to readers at home and abroad. Though the magazine was started just about the time when the depression struck the world, its success was immediate, and we are glad to say that its circulation has increased steadily every year. This is an eminently satisfactory claim to be able to make considering the times through which we have passed.

This article aims to focus on social structures and national and international factors as they influence international adoption. Special attention is paid to the impact of media, social welfare policies, legislation, and international monitoring groups on international adoption.

The article reviews relevant literature in sociology, social work, and the media. Much of the focus is on adoption in the USA since it has the largest number of internationally adopted children.

International adoption is becoming more common and is likely to continue to do so despite the concerns of some countries, some minority groups, and international monitoring agencies regarding trafficking in children, cultural genocide, and social justice issues related to transracial/intercultural adoption.

Adoption has generally been studied by social workers, psychologists and others concerned with its impact on the individual adoptee, birth mother and adoptive family. This article presents a sociological perspective of international adoption and considers its implications for families. The article is useful for policy makers, practitioners and others concerned with the occurrence of international adoption and its potential consequences.

The overall goal of science is to build a valid and reliable body of knowledge about the functioning of the world and how applying that knowledge can change it. As personnel and human resources management researchers, we aim to contribute to the respective bodies of knowledge to provide both employers and employees with a workable foundation to help with those problems they are confronted with. However, what research on research has consistently demonstrated is that the scientific endeavor possesses existential issues including a substantial lack of (a) solid theory, (b) replicability, (c) reproducibility, (d) proper and generalizable samples, (e) sufficient quality control (i.e., peer review), (f) robust and trustworthy statistical results, (g) availability of research, and (h) sufficient practical implications. In this chapter, we first sing a song of sorrow regarding the current state of the social sciences in general and personnel and human resources management specifically. Then, we investigate potential grievances that might have led to it (i.e., questionable research practices, misplaced incentives), only to end with a verse of hope by outlining an avenue for betterment (i.e., open science and policy changes at multiple levels).