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I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

Recounts the merger of Jerusalem’s Neighbourhood Self Management Organizations (NSMOs) and Community Service Organizations (CSOs) into the Joint Community Neighbourhood Management Organization (JCNM). Refers to literature on institutional theory and the process of decentralization. Focuses then on the NSMOs and CSOs, providing some background information on how and why they were originally set up and what their goals were. Compares the differences between the organizations, as well as the basic principles they have in common – hence the merge into one organization. Discusses the problems the JCNM has faced over the years, including issues such as identify, legitimacy, composition of board of directors, professional or political values, and restructuring the organization. Draws a quadrant model of patronage and centralization, suggesting that the NCNM aims to occupy a particular quadrant but is being hampered in doing so because policy makers prefer to keep things the way they are.

Cutoff frequency ƒT characteristics for AlGaAs/GaAs HBTs with planar structures are studied, by two‐dimensional simulation, with an emphasis placed on their dependences on the collector parameters. It is shown that the sub‐collector resistance becomes an important factor to achieve a higher ƒT in the high current region, and so it should be made as low as possible. Effects of introducing semi‐insulating external collectors are also studied. It is shown that the introduction of semi‐insulating layer is effective to improve the ƒT characteristics provided that it is slightly away from the intrinsic collector region.

Recent studies have shown that hyperuricemia is a predictor of non-communicable disease and an increment of mortality rate. Also, elevated serum uric acid may be associated with obesity in the adult population. This study aims to evaluate the association between serum uric acid levels with metabolic parameters and risk of obesity in the Iranian population.

The cross-sectional study was done on 550 participants, who were referred to a hospital for elective angiography in Rasht, Iran; anthropometric indices (waist circumference (WC) and body mass index (BMI)) and hematological factors were measured using the standard approaches. Based to the angiography results, the severity of atherosclerosis was defined.

The mean (SD) concentration of serum uric acid for all participants was 5.15 (1.37) mg/dl. Individuals who were at the highest tertile had higher mean (SD) of weight (p = 0.004), creatinine and blood urea nitrogen (p < 0.001) lower fasting blood sugar (FBS) (p = 0.000) and HbA1c (p = 0.016), and they were mostly men compared with those in the lowest tertile. After adjusting for confounders, FBS (ß = –0.145, p = 0.001) and HbA1c (%) (ß = –0.130, p = 0.019) had inverse and weight (ß = 0.156, p = 0.001) had direct association with serum uric acid. After adjustment for additionally potential confounders subjects in the highest tertile of serum uric acid had 92 per cent higher chance of obesity compared with subjects in the lowest tertile (OR 1.92; 95 per cent CI 1.13, 3.23).

The present study has concluded that increase serum uric acid related to high risk of obesity and low mean of FBS and HbA1c.

In this paper, we describe an energy transport simulation method for graded AlGaAs/GaAs HBTs, which uses Al composition‐, doping density‐, and energy‐dependent transport parameters estimated by a Monte Carlo method. For several representative Al composition x and doping densities, parameters such as electron mobility, energy relaxation time and upper valley fraction are evaluated as a function of electron energy. For the other x, these are determined by linear extraporation. The problem of this extraporation method is also described. Calculated cutoff frequency characteristics and electron velocity profiles are compared with those by using more simplified approaches, indicating the importance of using adequate transport parameters.

This article analyses and discusses spatial conditions contributing to confidentiality in HIV healthcare facilities carried out by two non-governmental organisations in Uganda, the AIDS Information Centre (AIC) and The AIDS Support Organisation (TASO). The provision of confidential space was found to be the most important architectural quality promoting client wellbeing, where Voluntary Counselling and Testing (VCT) as well as ongoing services to people living with HIV are provided. The study shows that confidential space is a requirement in a number of situations: when the client approaches the health centre; during the visit; and in the meeting between client, counsellor and medical staff. An unobtrusive location of the centre and separate, private counselling rooms are thus the most favourable spatial conditions.

This article is based on a qualitative, explorative case study carried out in Jinja, Uganda during four months in 2004. Direct observation, interviews, primarily with clients and staff, spatial analyses and a qualitative content analysis were carried out.

Numerical device simulation is developed to study the steady‐state and transient current‐voltage characteristics of double heterostructure AlGaAs/GaAs PNPN electro‐photonic device when its performance is influenced by the presence of interface and bulk recombination mechanism. The simulation results show that the holding current and voltage and the breakover point are strongly affected by varying the minority carrier lifetime at outer heterojunctions. Numerical results also indicate that shortening the minority carrier lifetime in the inner PN homojunction region only increases the OFF‐state current. These results are in agreement with experimental data on AlGaAs/GaAs PNPN devices. The numerical modelling approach taken in this study is shown to be essential in the design and optimization of PNPN switch.

The purpose of this paper is to investigate educational functions of the World Heritage Site by examining the case of cultural tourism in a Japanese Buddhist temple.

Japan accepted the World Heritage Convention in 1992. “Historic Monuments of Ancient Nara” were decided to be listed on the World Cultural Heritage in 1998. It was composed of buildings, monuments and related cultural landscape, including five Buddhist temples and one Shinto shrine. Among them, the Gango-ji, focused in this paper, is one of the oldest Buddhist temples in Japan.

It has been keeping many cultural properties related to the folk religious practice and providing many activities for the local community. The material culture of folk-belief is now preserved in a building in the temple yard. And there is an exhibition room. The main hall and the exhibition room are the important facilities for social education, where the visitors can watch and touch the real materials. According to the staffs of the temple, the tourists had better stay in the main hall after 1 h study at the exhibition room.

Heritage is a process of the contemporary people engaging in the usage of past as resources. The buildings as the tangible heritage used by the present community are combined with the actions as the intangible heritage of the people who preserve the heritage. The temporal tourists are also permitted to enjoy the process as participants. They can learn many things through their experiences at the heritage site.

A computer program for the solution of the single carrier semiconductor equations in GaAs has been developed to simulate charge storage and transfer in GaAs charge‐coupled devices. An uncoupled Newton method is used to solve the steady state problem, and a stable, uncoupled method is used for the transient solution. Using transient simulation, the transfer of a charge packet from well to well can be simulated over time. By comparing the size of the charge packet before and after the transfer, information on the charge transfer inefficency can be derived.

Numerical and analytical solutions of the carrier continuity equation are found for the problem of charge transfer in charge‐coupled devices in the presence of potential barriers. The analytical solution is for a rectangular potential barrier and is useful for obtaining a qualitative understanding of charge transfer over a potential barrier. Numerical results show that the charge transfer inefficiency is strongly affected when the shape of the potential barrier is varied and the height of the potential barrier remains fixed.