The plains of Sumatra and Kalimantan were sparsely populated at the turn of the 19th century (less than 4 inhabitants/km2), and the local population relied mainly on shifting cultivation of upland rice. The introduction of rubber by Dutch private Estates in the 1910's triggered a radical change in the landscape but no fundamental change in farming practices, at least at the beginning, with the ...

Abstract The stress state analysis of the sealing cylinder is great significance for safe operation system. In this study, we probe a system that can be simplified as an axisymmetric problem. service, rubber around central pipe contacts casing under action axial pressure, and thus function realized. analytical solution at interface derived based on Love strain in configuration. Then, relationsh...

Most dentists are educated in rubber dam use in dental school, but there is often disparity between what is taught for various restorative procedures and what is practiced in the private sector. It is a common, although undocumented, belief that few practicing dentists routinely use rubber dam isolation. This study repeated a survey conducted in 1985 evaluating U.S. general dentists' attitudes ...

BACKGROUND This survey study aimed at investigating the frequency of rubber dam use during root canal treatment, identifying influencing factors for not using it by Saudi general dental practitioners (GDPs) and endodontists. It also aimed at identifying measures that increase rubber dam usage. METHODS After obtaining an ethical approval, two pilot studies were conducted on staff members at Ta...

The goal of this study is to improve the thermal characteristics of high power LED (light-emitting diode) package using a flat heat pipe (FHP). The heat-release characteristics of high power LED package are analyzed and a novel flat heat pipe (FHP) cooling device for high power LED is developed. The thermal capabilities, including startup performance, temperature uniformity and thermal resistan...

Methods for estimating structural reliability using probability ideas are well established. When the residual ultimate strength of a buried pipeline is exceeded the limit, breakage becomes imminent and the overall reliability of the pipe distribution network is reduced. This paper is concerned with estimating structural failure of underground flexible pipes due to corrosion induced excessive de...

Although permeation of hydrocarbons such as Benzene, Toluene, Ethybenzene, and Xylene (BTEX) through polyethylene (PE) pipe in potable water applications is rarely occurred. It is important to understand permeation mechanism and characterize the potential health risk. The most common potential hydrocarbon substances are originated from gasoline leaks. Previous research has shown that pipe mater...

Ultrasonic fiber optic sensors (UFOS) based on Mach-Zehnder (M-Z) interferometer is proposed to detect guided waves propagating in the pipe, which is common structural component in aerospace, mechanical or civil structures. The sensitivity of UFOS depends on the long sensing distance, while winding around the circumferential direction of the pipe provides arbitrary sensing length as well as sma...

In this note we show a consequence of the recent observation that narrow-pipe hash designs manifest an abberation from ideal random functions for finding collisions for those functions with complexities much lower than the so called generic birthday paradox lower bound. The problem is generic for narrow-pipe designs including classic Merkle-Damg̊ard designs but also recent narrow-pipe SHA-3 cand...

Existing plant types of rubber tree after planting and available tapping tree were investigated, and there were about 28 rubber plantations with different tapping years of 8 varieties “CATAS7-33-97”, “CATAS8-79”, “CATAS7-20-59”, “PR107”, “RRIM600”, “GT1”, “INA873”, “93-114” in South China. The results showed that there were six kinds of existing plant types of rubber tree after planting of rubb...