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To realize the operation optimizing of today’s distribution power system (DPS), like economic dispatch, contingency analysis, and reliability and security assessment etc., it is beneficial and indispensable that a faster linear load flow method is adopted with a reasonable accuracy. Considering the high R/X branch ratios and unbalanced features of DPS, the purpose of this paper is to propose a faster and non-iterative linear load flow solution for DPS.

Based on complex function theory, the derivations of the injection current linear approximation have been proposed for the balanced and the single-, double- and three-phase unbalanced loads of DPS on complex plane. Then, a simple and direct linear load flow has been developed with loop-analysis theory and node-branch incidence matrix.

The methodology is appropriate for balanced and single-, double- and three-phase hybrid distribution system with different load models. It provides a fast and robust load flow method with a satisfactory accuracy to handle the problems of DPS whenever the load flow solutions are required.

The distributed generators (DGs) with unity or fixed power factors can be easily included. But the power and voltage nodes cannot be dealt with directly and need to be further studied.

By combining the current linear approximation with the loop theory-based method, a new linear load flow method for DPS has been proposed. The method is valid and acute enough for balanced and unbalanced systems and has no convergent problems.

The purpose of this paper is to analyze the mechanism of particle erosion in butterfly valve pipelines under hydraulic transportation conditions. The results will affect the sealing and safety of butterfly valve pipelines and hopefully serve as reference for the anti-erosion design of butterfly valve pipelines.

Through the discrete element method (DEM) simulation that considers the force between particles, the detached eddy simulation (DES) turbulence model based on realizable k-epsilon is used to simulate the solid-liquid two-phase flow-induced erosion condition when the butterfly valve is fully opened. The simulation is verified by building an experimental system correctness. The solid-liquid two-phase flow characteristics, particle distribution and erosion characteristics of the butterfly valve pipeline under transportation conditions are studied.

The addition of particles may enhance the high-speed area behind the valve. It first increases and then decreases with increasing particle size. With increasing particle size, the low-velocity particles change from being uniformly distributed in flow channel to first gathering in the front of the valve and, then, to gathering in lower part of it. Fluid stagnation at the left arc-shaped flange leads to the appearance of two high-speed belts in the channel. With increasing fluid velocity, high-speed belts gradually cover the entire valve surface by focusing on the upper and lower ends, resulting in the overall aggravation of erosion.

Considering the complexity of solid-liquid two-phase flow, this is the first time that the DEM method with added inter-particle forces and the DES turbulence model based on realizable k-epsilon has been used to study the flow characteristics and erosion mechanism of butterfly valves under fully open transportation conditions.

This paper examines diverging views on the Chongqing model, the policy experiment led by Bo Xilai from 2007 to 2012 that was famous for its “red songs” and the campaign against organized crime. It has impressed both the supporters of socialist identity of China and the supporters of liberal identity and led to an intense debate concerning China’s path of development. This paper attempts to discuss and clarify to what extent the Chongqing model represented a genuine socialist experiment and the implications of the model for China’s future.

This study aims to: first, examine the effect of interaction orientation (IO) and brand orientation (BO) on marketing capabilities and small and medium enterprises' (SMEs') performance, and second, assess the complementarity effect of IO and BO on marketing capabilities and SMEs' performance.

A model was developed and tested using a survey methodology. Data were collected from 538 SMEs located in Qatar and analysed by structural equation modelling with AMOS.

First, IO affects SMEs' performance only indirectly via marketing capabilities, whereas BO affects SMEs' performance both directly and indirectly. Second, contrary to expectations, the complementarity between IO and BO produced a destructive/suppressive effect, rather than a synergistic effect, on both marketing capabilities and SMEs' performance, reflecting the importance of a trade-off to enhance both marketing capabilities and SMEs' performance.

To the authors' knowledge, this is the first paper to examine the complementary effect of BO and IO on marketing capabilities and performance.

The purpose of this paper is to estimate the returns to rural schooling in China, addressing both endogeneity in rural individuals’ schooling and self-selection into off-farm work.

This paper exploits geographical proximity to rural secondary schools to create instrumental variables (IV) for individuals’ years of schooling. It addresses both endogenous schooling and self-selection using the two-step procedure developed in Wooldridge (2002, p. 586).

The preferred IV estimate of schooling returns, 7.6 percent, is considerably higher than most previous estimates found in rural China.

This paper is among the few papers that examine returns to rural schooling in China while simultaneously addressing both endogeneity in individuals’ schooling and self-selection into off-farm work. Its findings suggest that rural education in China is potentially able to generate a respectable level of economic returns if policies are designed to provide greater school accessibility to rural individuals.

The purpose of this paper is to design and implement a fully integrated low‐phase noise and large tuning range dual‐band LC voltage‐controlled oscillator (VCO) in 0.13 μm complementary metal oxide semiconductor (CMOS) technology.

Two parallel‐connected single‐band VCOs are designed to implement the proposed VCO. Adopting a simple and straight‐forward architecture, the dual‐band VCO is configured to operate at two frequency bands, which are from 1.48 GHz to 1.78 GHz and from 2.08 GHz to 2.45 GHz. A band selection circuit is designed to perform band selection process based on the controlling input signal.

The proposed VCO features phase noise of −104.7 dBc/Hz and −108.8 dBc/Hz at 1 MHz offset frequency for both low corner and high corner end of the low‐band operation. For high‐band operation, phase‐noise performance of −101.1 dBc/Hz and −110.4 dBc/Hz at 1 MHz offset frequency are achieved. The measured output power of the dual‐band VCO ranges from −8.4 dBm to −5.8 dBm and from −9.6 dBm to −8.0 dBm for low‐band and high‐band operation, respectively. It was also observed that the power differences between the fundamental spectrum and the nearby spurious tone range from −67.5 dBc to −47.7 dBc.

The paper is useful to both the academic and industrial fields since it promotes the concept of multi‐band or multi‐standard system which is currently in demand in the telecommunication industry.

The purpose of this paper is to provide a numerical study of conjugate heat transfer by mixed convection and conduction in a lid-driven enclosure with thick vertical porous layer. The effect of the relevant parameters: Richardson number (Ri=0.1, 1, 10) and thermal conductivity ratio (Rk=0.1, 1, 10, 100) are investigated.

The studied system is a two dimensional lid-driven enclosure with thick vertical porous layer. The left vertical wall of the enclosure is allowed to move in its own plane at a constant velocity. The enclosure is heated from the right vertical wall isothermally. The left and the right vertical walls are isothermal but temperature of the outside of the right vertical wall is higher than that of the left vertical wall. Horizontal walls are insulated. The governing equations are solved by finite volume method and the SIMPLE algorithm.

From the finding results, it is observed that: for the two studied cases, heat transfer rate along the hot wall is a decreasing function of thermal conductivity ratio irrespective of Richardson numbers contrary to the heat transfer rate along the fluid-porous layer interface which is an increasing function of thermal conductivity ratio. At forced convection dominant regime, the difference between heat transfer rate for upward and downward moving wall is insensitive to the thermal conductivity ratio. For downward moving wall, average Nusselt number is higher than that of upward moving wall.

Some applications: building applications, furnace design, nuclear reactors, air solar collectors.

From the bibliographic work and the authors’ knowledge, the conjugate mixed convection in lid-driven partially porous enclosures has not yet been investigated which motivates the present work that represent a continuation of the preceding investigations.

This paper aims to help scholars know about the focus and frontier in the field of corporate social responsibility (CSR). Although related research in CSR started 60 years ago, there is not much systematical literature review on CSR in recent years. This paper applies scientometric method, especially co-word analysis, to explore the frontier and focus of CSR in the twenty-first century, based on the articles from 2001 to 2014 in SSCI database.

In this paper, the authors first use the scientometric method and co-word analysis for keywords filtering and apply social network methodology to investigate the networks of high-frequency keywords and high-frequency authors.

The authors summarize the current state of CSR research in two aspects. By co-word analysis of high-frequency keywords, the findings show that the focus and frontier are highly related to CSR. Based on the findings of social network analysis, this paper concludes four important research directions and possible future research of CSR.

The findings in this paper will help scholars of CSR or other related fields to realize the focus and frontier of CSR and provide some guidance for their future research.

The purpose of this paper is to examine the role of independent vs interdependent self-construal in non-smokers’ responses to an anti-smoking message that focuses on either personal or relational consequences of smoking.

Two web-based experimental studies were conducted among US college non-smokers. In the first study, participants’ self-construal was measured. Then participants were randomly assigned to view an anti-smoking message emphasizing either relational or personal consequences of smoking. Message evaluation, smoking attitudes, and behavioral intentions were assessed after message exposure. The second study followed the same procedure except that participants’ self-construal was manipulated by randomly assigning participants to an independent or interdependent self-construal priming task prior to message exposure.

Both studies showed a noticeable pattern of interaction between message focus and self-construal: non-smokers with a salient interdependent self-construal responded more favorably to an anti-smoking message emphasizing personal (vs relational) consequences of smoking whereas non-smokers with a salient independent self-construal responded more favorably to an anti-smoking message emphasizing relational (vs personal) consequences of smoking. However, the interaction effect was small in the first study.

Findings from this study are original in that they run counter to the general belief that messages matching people’s self-perceptions will be more persuasive. On the other hand, matching health risk messages with people’s dominant self-construal may reduce the messages effectiveness due to defensive processing. As a result, communication practitioners should take a great caution of tailoring threatening smoking prevention messages to target audiences’ self-perceptions.

How do institutional pressures influence the cluster firm’s innovation? Institutional pressure consists of regulative, normative and cognitive pressures; most scholars have only focused on the influence of regulative pressure as institutional environment on innovation. In addition, the nature of strategic cognition, as the mediator act on innovation strategy, remains underexplored in the literature. Based on institution theory and ambidextrous innovation theory, this study aims to propose a framework to examine the mechanism of institutional pressures acting on ambidextrous innovation through the moderated mediating role of strategic cognition in clusters.

Using survey data collected from 422 sampled firms in China, regression models were used to test hypotheses from the mediating role of strategic cognition between institutional pressures and cluster firm’s ambidextrous innovation.

The results showed that regulative, cognitive pressures and, especially, normative pressures have significant positive effects on cluster firms’ ambidextrous innovation. Strategic cognition presented by prospector and analyzer mediates the relationship between institutional pressure and ambidextrous innovation except defender; dynamic environment positively moderates the mediating effects of prospector cognition on explorative innovation, and negatively moderates the mediating effects of analyzer cognition on exploitative innovation.

The findings of this study have some implications that strategic cognition played a partially meditating role between the institutional pressure and ambidextrous innovation. Government should construct a dynamic innovation policy system according to the resource endowment in different regions; furthermore, classification support system to cluster firms with different strategic cognition should be built.