History of geothermal exploration in Indonesia from 1970 to 2000

Reconnaissance surveys undertaken since the 1960s show that more than 200 geothermal prospects with significant active surface manifestations occur throughout Indonesia. Some 70 of these were identified by the mid-1980s as potential high-temperature systems using geochemical criteria of discharged thermal fluids. Between 1970 and 1995, about 40 of these were explored using geological mapping, geochemical and detailed geophysical surveys. Almost half of the surveyed prospects were tested by deep (0.5–3 km) exploratory drilling, which led to the discovery of 15 productive high-temperature reservoirs. Several types of reservoirs were encountered: liquid-dominated, vapour-dominated, and a vapour layer/liquid-saturated substratum type. All three may be modified by upflows (plumes) containing magmatic fluid components (volcanic geothermal systems). Large, concealed outflows are a common feature of liquid-dominated systems in mountainous terrain. All explored prospects are hosted by Quaternary volcanic rocks, associated with arc volcanism, and half occur beneath the slopes of active or dormant stratovolcanoes. By 1995, five fields had been developed by drilling of production wells; three of them supplied steam to plants with a total installed capacity of 305 MW_e. By 2000, with input from foreign investors, the installed capacity had reached 800 MWe in six fields, but geothermal developments had stalled because of the 1997–1998 financial crisis.     

螺栓连接单搭接件疲劳特性试验与全寿命估算方法研究

飞机搭接件结构在疲劳载荷下会产生裂纹并扩展,而目前对搭接件结构参数与其疲劳寿命的关系研究还不够系统,且寿命估算模型只考虑了全寿命的一部分。对不同结构参数的三螺栓单搭接件的疲劳特性进行了试验研究,并以现有工程方法为基础,构建了基于材料初始不连续状态的搭接件全寿命估算模型。结果表明,搭接件的疲劳破坏具有一定的隐蔽性,在一定条件下,采用直孔形式、增大孔间距和螺栓预紧力、减小孔直径等都可以改善搭接件的疲劳特性。数值估算结果与试验结果的对比表明,所建寿命模型具有一定的精度,能满足工程需要,计算结果和结论可作为该类结构损伤容限设计的参考依据。     

数值分析在确定竖井保安矿柱与回采方案中的应用

本文首先简述了矿层单元与竖井单元的理论结果,讨论了矿山开采岩体分级在选定力学模型中的作用。结合某矿山竖井保安矿柱重新圈定的实际问题,运用矿层单元与竖井单元进行了板状矿体开采对竖井影响的三维分析,充分发挥电子计算机与数值方法的长处,经过对多种可能回采方案的试算与比较,得到了矿山生产设计中急需的参考数据。     

农村公路桥梁损伤状况调查研究

通过湖北黄石地区农村公路桥梁的实地调查,采用权重综合评定法,对农村公路桥梁按损伤程度进行了分类研究,结果表明中等损伤的三类桥居多,损伤基本集中在7个部位,病害类型以混凝土裂缝、混凝土腐蚀、钢筋锈蚀、桥面铺装损伤为主。为后期桥梁加固提供了调查依据。     

The effect of stream regulation on the physico-chemical properties of the palmiet river,South Africa

The effect of regulation, by multiple impoundment, on ‘discontinuity’ (recovery) ‘distances’ (sensu Ward and Stanford, 1983) for various physico-chemical attributes of the Palmiet River (a short, steep gradient, cool temperate, acid, low-nutrient system) was investigated. Physico-chemical features were measured monthly, from February 1986 to August 1987, at 11 sites along the river, but concentrating on two zones: one below an upper-reach impoundment, Nuweberg Dam, and one below a middle-reach impoundment, Arieskraal Dam. Median total suspended solids, nitrates, nitrites and ammonium all increased below both dams with varying levels of ‘recovery’. Median spot temperatures, pH and alkalinity increased below Nuweberg, but decreased below Arieskraal Dam, whereas the converse was true for soluble reactive phosphate. Nuweberg had no effect on conductivity and total dissolved solids, while Arieskraal caused a slight decrease. The river remained well oxygenated down its length. Distinct seasonal variations were recorded for: flow rate, with flow reversal below Nuweberg and flow constancy below Arieskraal; temperature, with seasonal shifts and dampening of annual temperature range below both dams; alkalinity, with seasonal shifts below Arieskraal, and nitrites and nitrates, but not for any other attributes. At least partial recovery was noted in all cases, but in some instances, recovery was incomplete to the estuary. The implications of such alterations, for invertebrates, in terms of reduction in habitat diversity as well as for food supply must be considerable and studies are currently under way to determine community structure and diversity.     

角度相关不连续因子在JRR3M堆芯输运计算中的应用

针对含有强吸收体控制组件的日本研究堆JRR3M,在进行堆芯输运方程计算时,给出了角通量不连续因子(AFDF)的定义,并指出使用角通量不连续因子的必要性,提出使用迭代求解的方法来提高计算精度,并使之满足不连续因子自洽性。针对堆芯设计计算量大的特点,使用了超栅元近似方法。该方法能有效缩短计算时间,且灵活性强。利用组件形状函数,能重构出非均匀模型堆芯通量分布。最后讨论了扩散计算时不连续因子的选取问题,指出根据参考的不同,应选择不同的不连续因子。     

Applicability of angular flux discontinuity factor preserving region-wise leakage for integro-differential transport equation

In the current core analysis, spatial homogenization is utilized to reduce the computational time. The discontinuity factor (DF) is one of the effective correction factors to reduce spatial homogenization error. The DF in diffusion equation is widely used; on the other hand the DF in transport equation has not been put to practical use although several efforts have been carried out. In this paper, the angular flux discontinuity factor (AFDF) as the DF for the integro-differential transport equation (e.g., the discrete-ordinate method, the method of characteristics) is theoretically described and its applicability is discussed. The AFDF is used to preserve the region-wise neutron leakage at each spatial mesh and defined as a ratio of heterogeneous and homogeneous angular fluxes at the homogenized region surface. In a homogeneous calculation with the AFDF, the angular flux is discontinuous at the region surface. In this paper the applicability of the AFDF to fuel pin cell homogenization is verified for one-dimensional slab geometry. As a result of this verification, it is confirmed that the AFDF has the capability to reduce the spatial homogenization error of fuel pin cell homogenization.     

Development of Parallel Coupling System between Three-Dimensional Nodal Kinetic Code ENTREE and Two-Fluid Plant Simulator TRAC/BF1

The high-speed three-dimensional neutron kinetic code ENTRÉE was developed based on the polynomial and semi-analytical nonlinear iterative nodal methods (PNLM and SANLM) with also introducing the discontinuity factor. In order to enhance the efficiency of transient calculation, the nonlinear correction-coupling coefficients are intermittently updated based on the changing rate of core state variables. By giving the analytical form for two-node problem matrix elements, the additional computing time in SANLM was minimized. A fast algorithm was developed for the multi table macro-cross section rebuilding process. The reactivity component model was implemented based on the variation of the neutron production and destruction terms. The code was coupled with the two-fluid thermal hydraulic plant simulator TRAC/BF1 through PVM or MPI protocols. Two codes are executed in parallel with exchanging the feedback parameters explicitly. Based on the LMW PWR transient benchmark, it was shown that both PNLM and SANLM spend less than 20% excess computing time in comparison with the coarse mesh finite difference method (CFDM). The implementation of the discontinuity factor was verified based on the DVP problem. Adequacy and parallel efficiency of the coupling system TRAC/BF1-ENTREE was demonstrated based on the BWR cold water injection transient proposed by NEA/CRP.     

The "never-to-be-forgotten investigation": Luella W. Cole, Sidney L. Pressey, and mental surveying in Indiana, 1917–1921.

The case of Cole and Pressey's mental survey of southern counties in Indiana provides a microhistorical view of intelligence testing and its popularization. Providing fresh insight into the nature and commerce of mental surveying outside of the Army's notorious program during World War I, this case is an example of larger phenomena at that time. Intent on popularizing their products, Cole and Pressey attended to the minutiae of the consumption and production of their psychological apparatus in their attempts to create and satisfy market conditions. Here, markets would dictate the success of their scales, and in turn mediate their psychology. I argue that the popularization of intelligence testing had as much to do with the mundane market practices of psychologists as with the intellectual practices of Army elites. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An extended displacement discontinuity method for analysis of stress wave propagation in viscoelastic rock mass

An extended displacement discontinuity method (EDDM) is proposed to analyze the stress wave propagation in jointed viscoelastic rock mass (VRM).The discontinuities in a rock mass are divided into two groups.The primary group with an average geometrical size larger than or in the same order of magnitude of wavelength of a concerned stress wave is defined as "macro-joints",while the secondary group with a high density and relatively small geometrical size compared to the wavelength is known as "micro-defects"...