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Conventional OR/systems practice, it is argued in this paper, is based upon assumptions which make it unsuitable for guiding interventions in nontraditional organizations. Any methodology or method rests upon a social theory,upon craft knowledge, and upon a theory of how change can and should be brought about. Conventional OR/systems is not explicit about any of these matters. Reflecting on why conventional methods often fail to work with nontraditional organizations, however, enables us to get beneath the iceberg and unearth what is being taken for granted. It is then obvious that the nature of many organizations in the social economy requires a different type of practice. Soft OR/systems is a response to the failings of the traditional approach, but goes only some way toward meeting the criticisms.  相似文献   
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Buoyant density of herpes simplex virus in solutions of caesium chloride   总被引:5,自引:0,他引:5  
P G Spear  B Roizman 《Nature》1967,214(5089):713-714
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3.
Walker JJ  Spear JR  Pace NR 《Nature》2005,434(7036):1011-1014
The endolithic environment, the pore space of rocks, is a ubiquitous habitat for microorganisms on the Earth and is an important target of the search for life elsewhere in the Solar System. Photosynthetic, endolithic microbial communities commonly inhabit the outer millimetres to centimetres of all rocks exposed to the Earth's surface. In the most extreme terrestrial climates, such as hot and cold deserts, endolithic microorganisms are often the main form of life. The endolithic microhabitat gives protection from intense solar radiation and desiccation, and it provides mineral nutrients, rock moisture and growth surfaces. Here we describe the discovery and identification of the constituents of an extremely acidic (pH 1) endolithic microbial community inhabiting the pore space of rocks in the geothermal environment of Yellowstone National Park, USA. Subjected to silica mineralization, such endolithic communities constitute biomarkers that can become fossilized and potentially preserved in the geological record. Remnants of these communities could serve as biosignatures and provide important clues about ancient life associated with geothermal environments on the Earth or elsewhere in the Solar System.  相似文献   
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This paper explores some of the unilluminated or less explicit aspects of issues faced by those using systems approaches in real-world problem situations. The paper contends that discourse on systems approaches tends to be dominated by rational logical aspects of methodology, though other aspects of the intervention process, such as political dimensions of legitimacy, have become more important in the last 10–15 years. Unsurprisingly the discourse has been different for different methods. Method has been largely invisible in the hard systems area (or at least relatively little discussed), and although it has been the subject of much debate in the soft systems area, the debate has been nonetheless narrowly defined. It is narrowly defined in its relative neglect of process aspects for conducting a systems study. Since the nature of these processes (for example, the client/consultant relation) changes from hard systems to soft systems to critical systems in a way that makes social process progressively a more important dimension of each approach, this aspect has featured more in discourse on critical systems, but in general it remains a curious area of neglect. There is increasing interest in this area, and some signs that relevant theory and practice from closely related domains is being accessed to strengthen these approaches. This paper attempts to make a contribution by outlining and discussing some areas that could usefully complement existing systems approaches. The paper considers the following areas: (a) client relations, (b) analyst role, (c) language and communication, (d) group processes, (e) culture (and rationalities), (f) information gathering techniques and processes, and (g) change management or implementation. The paper draws on experiences of systems practices in the literature, interviews with systems practitioners, and writings in related areas. The paper ends by discussing some of the implications of these issues for the development of well-rounded systems approaches.  相似文献   
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B Roizman  J M Keller  P G Spear  M Terni  A Nahmias  W Dowdle 《Nature》1970,227(5264):1253-1254
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