单一震源地震发生的等效物理模型

建立了模拟单一潜在震源区地震孕育和发生的等效物理模型，给出了通过调整各次地震之间断层位移速率来拟合已有地震序列的方法。通过考虑模型参数的不确定性，提出了在未来一定年限内潜在震源区发生震级在不同震级段的概率预报方法。通过两种等效物理模型的对比，本文认为就工程地震危险性评定而言，可用简单的滑块－弹簧模型代替滑块－弹粘塑性模型     

Electromagnetic fields in offices.

With the increased use of electric and electronic equipment in our offices, our daily exposure to electromagnetic fields has become increasingly complex due to the great variety of the frequency content of the fields. Today focus has shifted from monitors as the dominating sources of electromagnetic fields to other electronic equipment, cabling, nearby substations, power lines and stray currents in buildings. In the last 5 years wireless communication has become common in our offices. These devices use radio frequency waves to communicate and are therefore sources of radio frequency fields in our offices. To a certain degree, they all add to the complicated issue of the extensive field frequencies found in offices. The exposure of office workers is generally considered to be low and not in conflict with the existing guidelines, but if a precaution approach is applied there are a number of measures that can be taken to reduce the electromagnetic fields in offices in order to obtain a good electrical environment.     

高邮人的筑台与古今防汛

高邮人有筑台御水的传统。据明隆庆《高邮州老·建置志》记载:“秦并楚、(高邮)又居秦,始建台,置邮亭,名秦邮。”说明秦朝在建高邮亭时曾先筑高台,又因邮亭是建在高高的土台上,便被形象地称为“高邮亭”,且邮亭系秦所建,故后人又称高邮为“秦邮”。秦代建高邮亭时为什么要先筑高台呢?这是因为高邮地处里下河地区,地势低洼,不筑台就不能抵御洪水。高邮     

Leachability testing of metallic wastes.

The performance of two tests, a batch test and a percolation test for the characterization of waste as suggested in the EU council decision 2003/33/EC was investigated. The tests were carried out on two solid waste streams from a metal recycling industry. The concentrations of heavy metals such as Cu, Zn and Pb were more than one order of magnitude lower than the proposed limit values. Generally, batch test values were equal or higher than percolation test values. With the proposed test procedures both materials could be considered as non-dangerous wastes. The test performance was also investigated using a leachant with higher ionic strength instead of demineralized water as prescribed. The results clearly show a significant increase in the concentration of some heavy metals. Total concentrations of phenolic compounds and polychlorinated biphenyls were less than 1 p.p.m. and 2 p.p.b., respectively. The precision of the batch and the percolation tests were on average 48 and 35%, respectively.     

The effect of an ergonomic intervention on musculoskeletal, psychosocial, and visual strain of VDT data entry work: the Polish part of the international study.

A group of routine data entry operators (female) was included in the Polish MEPS (musculoskeletal--eyestrain--psychosocial--stress) study. Before the intervention, ergonomic assessment revealed improper working conditions such as inadequate lighting, uncomfortable chairs, and lack of forearm and wrist support while medical examination revealed that trapezius muscle load along with upper arm, head and back angles were higher than advisable. Subjects complained about neck and shoulder pain, visual problems, and psychosocial conditions. The ergonomic intervention included installation of new luminaires and Venetian blinds, new chairs, repair of ventilators, and optometric corrections. The results after the intervention showed mainly improvement in chair comfort, lighting conditions, visual strain, and sitting posture. However, financial limitations did not allow satisfactory completion of the intervention leading to a mixed interpretation of the results.     

A cross-country comparison of short- and long-term effects of an ergonomic intervention on musculoskeletal discomfort, eyestrain and psychosocial stress in VDT operators: selected aspects of the international project.

Three groups of data entry female visual display terminal (VDT) workers from Norway (n = 30), Poland (n = 33) and the USA (n = 29) were compared. Before intervention, the Norwegian group reported more neck pain compared with the Polish group. The Polish group reported less shoulder pain than both the U.S. and the Norwegian groups. The clinical examination documented fewer symptoms and signs of musculoskeletal illness among the Polish participants compared with the Norwegian and the U.S. groups. After intervention, the Norwegian group reported a reduction in neck pain while the U.S. group reported a reduction in shoulder pain. The Polish group reported an increase in neck, shoulder and forearm pain at follow-up compared to after intervention. The Polish group recorded higher flexion of the upper arm at follow-up parallel with an increase of pain in the upper part of the body. Visual discomfort showed variable results in the 3 countries.     

Safety climate in Finnish- and Swedish-speaking companies.

The aim of this study was to compare assessments made by Finnish- and Swedish-speaking workers in Finland about the safety climate in their companies, because an earlier study showed that the accident frequency of Swedish-speaking workers was one third lower than that of Finnish-speaking workers. 148 Finnish-speaking and 138 Swedish-speaking workers from 14 small and medium-sized companies participated in this study. They filled out a Finnish safety climate questionnaire, the reliability of which was above the acceptable level. There were no differences between the language groups in the total variables of safety climate and safety action. Based on the differences in single items, we interpreted that Swedish-speaking workers stressed collective safety more, whereas Finnish-speaking workers put more emphasis on their personal responsibility for safety.     

Public Perception of Flood Hazard in the Niger Delta,Nigeria

Summary Our study had the aim of understanding how floodplain dwellers regard the risk of flooding. About 500 questionnaires were administered to landowners in the selected settlements in the study area using systematic random sampling. The results of analysis show, among other things, that the population regards most important the causes of floods as heavy, prolonged rainfall and river overflow. Nevertheless, they have little knowledge of the frequency of severe floods, and flood alleviation schemes. Most flood victims do not get compensation or relief during flood disaster, and the reason why they remain in the study area is influenced by their occupations, especially fishing, subsistence agriculture, and the presence of crude oil in the region which has attracted many migrants who cannot afford the high cost of accommodation and are therefore forced to live in vulnerable areas of the floodplain. Finally, the study concludes that flood control in the region needs the cooperation of government, community efforts and an enlightenment programmes through environmental education and mass media.     

Non-native Species <Emphasis Type="Italic">DO</Emphasis> Threaten the Natural Environment!

Sagoff [Journal of Agricultural and Environmental Ethics 18 (2005), 215–236] argues, against growing empirical evidence, that major environmental impacts of non-native species are unproven. However, many such impacts, including extinctions of both island and continental species, have both been demonstrated and judged by the public to be harmful. Although more public attention has been focused on non-native animals than non-native plants, the latter more often cause ecosystem-wide impacts. Increased regulation of introduction of non-native species is, therefore, warranted, and, contra Sagoff’s assertions, invasion biologists have recently developed methods that greatly aid prediction of which introduced species will harm the environment and thus enable more efficient regulation. The fact that introduced species may increase local biodiversity in certain instances has not been shown to result in desired changes in ecosystem function. In other locales, they decrease biodiversity, as they do globally.     

Class: an Essential Aspect of Watershed Planning

A study of a watershed planning process in the Cache River Watershed in southern Illinois revealed that class divisions, based on property ownership, underlay key conflicts over land use and decision-making relevant to resource use. A class analysis of the region indicates that the planning process served to endorse and solidify the locally-dominant theory that landownership confers the right to govern. This obscured the class differences between large full-time farmers and small-holders whose livelihood depends on non-farm labor. These two groups generally opposed one another regarding wetland drainage. Their common identity as “property owner” consolidated the power wielded locally by large farmers. It also provided an instrument – the planning document – for state and federal government agencies to enhance their power and to bring resources to the region. The planning process simultaneously ameliorated conflicts between government agencies and the large farmers, while enhancing the agencies’ capacity to reclaim wetlands. In this contradictory manner, the plan promoted the environmental aims of many small-holders, and simultaneously disempowered them as actors in the region’s political economy. An erratum to this article is available at .