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1.
面向生态文明的超循环经济:理论、模型与实例 总被引:1,自引:0,他引:1
在全球气候变化背景下,研究适应生态文明要求的新的经济运行模式——超循环经济的基本原理、结构模型、运行机理和实际应用。首先,运用系统结构分析方法梳理不同时期经济运行模式的演进过程:由"从摇篮到产品"的粗放经济,到"从摇篮到坟墓"的末端治理经济,再到"从摇篮到摇篮"的循环经济。延续这一绿色发展趋势,根据文明演化的共生理论和艾根创立的超循环理论,提出超循环经济的理论构想,并描绘"从孕育到孕育"的超循环经济的概念结构。其次,将超循环经济思想应用于林纸拓展系统(EFPS)。在分析中国造纸工业的发展现状和瓶颈及其与林业和生态环境相互关系的基础上,按照资源链、生态链和价值链(简称"三链",或3C)逐层拓展的逻辑顺序,研究EFPS超循环经济的系列结构模型。具体来说,依次建立起各层次的超循环结构模型——制浆造纸系统的资源链核心层模型、供应链系统的资源链拓展层模型、生态环境系统的生态链拓展层模型,以及社会经济系统的价值链拓展层模型。然后将各层次的结构模型综合起来,形成EFPS超循环经济的多重拓展-嵌套整体模型。该模型既能展示EFPS超循环经济系统的全貌,又包含其各层次的系统结构。因此既能为各级政府在制定国家和地区的循环经济总体发展规划时提供参考,又能为制造企业、营林组织、供应链、行业协会等各类经济主体的绿色经营决策提供支撑。最后,在上述实证研究的基础上进行理论提升。一方面提出超循环经济的5R原则:减量化、再循环、再利用、再分配和再培育。另一方面基于5R原则和3C循环链,构建5R-3C理论模型,并研究其5R-3C共生运行机理。研究表明,在超循环经济模式下,产业与生态系统可以实现互利共生的良性循环。以上研究成果的主要创新之处在于:在原理上,揭示了面向生态文明的超循环经济的概念结构、本质属性和5R原则;在机理上,创立了超循环经济的5R-3C模型及其共生运行机理;在实施上,以林纸拓展系统为例,为超循环经济理论的"落地生根"和推广应用构建了具体的多重拓展-嵌套模型。 相似文献
2.
Vos RA Balhoff JP Caravas JA Holder MT Lapp H Maddison WP Midford PE Priyam A Sukumaran J Xia X Stoltzfus A 《Systematic biology》2012,61(4):675-689
In scientific research, integration and synthesis require a common understanding of where data come from, how much they can be trusted, and what they may be used for. To make such an understanding computer-accessible requires standards for exchanging richly annotated data. The challenges of conveying reusable data are particularly acute in regard to evolutionary comparative analysis, which comprises an ever-expanding list of data types, methods, research aims, and subdisciplines. To facilitate interoperability in evolutionary comparative analysis, we present NeXML, an XML standard (inspired by the current standard, NEXUS) that supports exchange of richly annotated comparative data. NeXML defines syntax for operational taxonomic units, character-state matrices, and phylogenetic trees and networks. Documents can be validated unambiguously. Importantly, any data element can be annotated, to an arbitrary degree of richness, using a system that is both flexible and rigorous. We describe how the use of NeXML by the TreeBASE and Phenoscape projects satisfies user needs that cannot be satisfied with other available file formats. By relying on XML Schema Definition, the design of NeXML facilitates the development and deployment of software for processing, transforming, and querying documents. The adoption of NeXML for practical use is facilitated by the availability of (1) an online manual with code samples and a reference to all defined elements and attributes, (2) programming toolkits in most of the languages used commonly in evolutionary informatics, and (3) input-output support in several widely used software applications. An active, open, community-based development process enables future revision and expansion of NeXML. 相似文献
3.
Eisen L Coleman M Lozano-Fuentes S McEachen N Orlans M Coleman M 《PLoS neglected tropical diseases》2011,5(3):e1016
Background
Emerging information technologies present new opportunities to reduce the burden of malaria, dengue and other infectious diseases. For example, use of a data management system software package can help disease control programs to better manage and analyze their data, and thus enhances their ability to carry out continuous surveillance, monitor interventions and evaluate control program performance.Methods and Findings
We describe a novel multi-disease data management system platform (hereinafter referred to as the system) with current capacity for dengue and malaria that supports data entry, storage and query. It also allows for production of maps and both standardized and customized reports. The system is comprised exclusively of software components that can be distributed without the user incurring licensing costs. It was designed to maximize the ability of the user to adapt the system to local conditions without involvement of software developers. Key points of system adaptability include 1) customizable functionality content by disease, 2) configurable roles and permissions, 3) customizable user interfaces and display labels and 4) configurable information trees including a geographical entity tree and a term tree. The system includes significant portions of functionality that is entirely or in large part re-used across diseases, which provides an economy of scope as new diseases downstream are added to the system at decreased cost.Conclusions
We have developed a system with great potential for aiding disease control programs in their task to reduce the burden of dengue and malaria, including the implementation of integrated vector management programs. Next steps include evaluations of operational implementations of the current system with capacity for dengue and malaria, and the inclusion in the system platform of other important vector-borne diseases. 相似文献4.
Mingyao Liu Shahram Montazeri Tony Jedlovsky Ryan van Wert Jun Zhang Ren-Ke Li Jun Yan 《In vitro cellular & developmental biology. Animal》1999,35(2):87-93
Summary In the present study, a unique mechanical strain apparatus for three-dimensional organotypic cultures was developed into a
computerized system. It consists of a personal computer running Windows-based software, the Bio-Stretch Manager, a Bio-Stretch
Controller, and three sets of magnet boards. Cells are cultured on a Gelfoam? sponge that is placed in a 35-mm petri dish
with one end glued to the dish, and the other end attached to a coated steel bar. The petri dish is placed in front of a magnet,
and the movement of the steel bar is controlled by dynamically changing the magnetic field. Up to five stretch patterns of
variable frequency, duty cycle, and magnitude can be designed for each stretch regimen. Three different stretch regimens can
be tested simultaneously. The operational characteristics of sponges were examined. Attachment of cells to the sponges was
observed on several cell types. These features provide wide options for using this system to study the effects of mechanical
stretch on cells. 相似文献
5.
Raw hydrobiological (abundance, biomass, and numbers of phytoplankton, zooplankton, zoobenthos, periphyton, and bacterioplankton species) and physicochemical indices of ecosystems are integrated into information system Ecology of Freshwater in Russia and Neighboring Countries. This system is dedicated to environmental control by biotic indices in former USSR countries. The information system is realized as an Ecograde application based on Microsoft Access software as well as a web site. 相似文献
6.
Andrew Arno 《American anthropologist》2003,105(4):807-819
The ethnographic interpretation of "meaningless" ritual—ritual in which participants are not able to give verbal accounts of the symbolic meanings involved—poses basic questions about the relationships among language, culture, and meaning. Along with verbal meaning expressible in language, rituals are often observed to have important practical meaning outside of language. Aside from basic how-to, facilitating dimensions, practical meaning systems can also constitute metaphor and accomplish reference in ways that are parallel to, yet distinct from, verbal and gestural language functions. Techniques of language analysis are useful in interpreting practical meaning in ritual if language meaning is viewed from the perspective of Wittgensteinian use-based semantics and language is seen in context of a more general multidomain meaning system module that supports the communicative aspects of culture. [Keywords: ritual, aesthetics, communication, ethnography, Fiji] 相似文献
7.
Nantamol Limphitakphong Chanathip Pharino Premrudee Kanchanapiya 《The International Journal of Life Cycle Assessment》2016,21(12):1789-1798
Purpose
Urbanization and industrial development intensify water utilization and wastewater generation. The efficiency of wastewater treatment systems varies and depends on system design and wastewater condition. The research aims to examine seven existing centralized municipal wastewater treatment plants (WWTPs) in Bangkok to discover which system configuration yields the best environmental and economic performance. The degree of environmental impact and operational costs from different system designs were investigated to help select future wastewater treatment systems.Methods
Life cycle assessment (LCA) has been conducted to evaluate environmental impacts from centralized municipal wastewater treatment systems. Life cycle impact assessment method based on endpoint modeling (LIME) was applied, with three major potential environmental impact categories including eutrophication, global warming, and acidification. All seven centralized municipal WWTPs in Bangkok were investigated as case studies. The system configurations are classified into five types of activated sludge (AS) systems. The contribution of impacts from individual processes in each type of AS system was analyzed. The methodology covered major on-site and off-site operational processes excluding construction and maintenance phases. Average annual data were calculated to develop an inventory dataset. JEMAI-Pro software was utilized in this study to analyze the life cycle impact of the systems.Results and discussion
The level of environmental impact from a WWTP depends on the configuration of the AS system. The highest potential environmental impact from a municipal WWTP is eutrophication, which is obviously affected by ammonium and phosphorous discharges into water bodies. The vertical loop reactor activated sludge (VLRAS) system yielded the best treatment performance among the five AS sub-systems. The consumption of electricity used to operate the system contributed significantly to global warming potential and correlated considerably with operating costs. Comparing among three system sizes, the large-scale WWTP revealed inefficient electricity consumption, whereas the medium plant provided better performance in chemical use and operating costs.Conclusions
Centralized municipal WWTPs with capacities ranging from 10 to 350?×?103 m3/day were evaluated with respect to environmental performance and costs during the operating phase. Among all case studies, a medium-scale WWTP with a VLRAS system offered the best operating performance in terms of low environmental impact, resource consumption, and cost. To enhance WWTP management, it is vital to improve the efficiency of electricity consumption in primary and secondary treatment processes and increase wastewater collection efficiency to maximize the plant operating capacity and minimize overall environmental impacts.8.
Debby G Keuken Joke A Haafkens Marian J Hellema Jako S Burgers Clara J Moerman 《Implementation science : IS》2007,2(1):1-7
Background
The Research-Based Education and Quality Improvement (ReBEQI) European partnership aims to establish a framework and provide practical tools for the selection, implementation, and evaluation of quality improvement (QI) interventions. We describe the development and preliminary evaluation of the software tool NorthStar, a major product of the ReBEQI project.Methods
We focused the content of NorthStar on the design and evaluation of QI interventions. A lead individual from the ReBEQI group drafted each section, and at least two other group members reviewed it. The content is based on published literature, as well as material developed by the ReBEQI group. We developed the software in both a Microsoft Windows HTML help system version and a web-based version. In a preliminary evaluation, we surveyed 33 potential users about the acceptability and perceived utility of NorthStar.Results
NorthStar consists of 18 sections covering the design and evaluation of QI interventions. The major focus of the intervention design sections is on how to identify determinants of practice (factors affecting practice patterns), while the major focus of the intervention evaluation sections is on how to design a cluster randomised trial. The two versions of the software can be transferred by email or CD, and are available for download from the internet. The software offers easy navigation and various functions to access the content. Potential users (55% response rate) reported above-moderate levels of confidence in carrying out QI research related tasks if using NorthStar, particularly when developing a protocol for a cluster randomised trialConclusion
NorthStar is an integrated, accessible, practical, and acceptable tool to assist developers and evaluators of QI interventions. 相似文献9.
The goal of this article is to present the Human Health Risk Assessment (HRA) software developed as one of the NORISC 1 decision support software system components that could be used as a tool for facilitating management of urban contaminated sites. The NORISC-HRA software provides sufficient technical and procedural support to conduct a simple site-specific risk assessment. The employed HRA methodology is generally based on U.S. Environmental Protection Agency (USEPA) procedures. The software determines the level and spatial distribution of human health risks at a given site and sets up site-specific preliminary Health-Based Remedial Goals (HBRGs)/Risk-Based Concentrations (RBCs) for soil and groundwater. The NORISC-HRA software is recommended for use when national soil and groundwater limit values are exceeded. Exposure pathways considered in this software are associated with three land use patterns—residential, industrial/commercial, and recreational. The aricle also presents the software testing results obtained at one of the NORISC test sites—the Massa site (Avenza-Carrara, Tuscany, Italy). Findings of the HRA indicated that the contaminated soil at the Massa test site might pose potential cancer and non-cancer risks to industrial workers in its present condition. Arsenic was the dominant substance responsible for most of the baseline risk and at the RBC of 1.77 mg/kg it was the primary driver of remedial decisions at the Massa site. 相似文献
10.
J. Votruba 《Engineering in Life Science》1982,2(2):119-126
Most mathematical models for describing the physiological state in fermentations lead to solutions of the so-called “stiff differential systems” during simulation on a digital computer There is no suitable conventional software for solving these systems As a result of a relatively extensive screening of suitable methods for the solution of “stiff” differential systems (about 200 methods) it may be concluded that the semiimplicit RUNGE -KUTTA -formulas of the ROSENBROCK type, which constitute a part of the collection of programmes STIFFSOLVER-80, are optimal for the simulation of fermentation processes For determining kinetic parameters from integral data the authors use the system of programmes BIOKIN Their practical application is discussed for 3 examples:
- 1 Growth of the yeast Saccharomyces cerevisiae and changes in the content of specific compounds (proteins and ergosterol)
- 2 Quantitative evaluation of “;direct oxygen transfer” in the submerged culture.
- 3 Biosynthesis of a new antibiotic substance mucidin
11.
Reinout Heijungs Manfred Lenzen 《The International Journal of Life Cycle Assessment》2014,19(7):1445-1461
Purpose
The analysis of uncertainty in life cycle assessment (LCA) studies has been a topic for more than 10 years, and many commercial LCA programs now feature a sampling approach called Monte Carlo analysis. Yet, a full Monte Carlo analysis of a large LCA system, for instance containing the 4,000 unit processes of ecoinvent v2.2, is rarely carried out by LCA practitioners. One reason for this is computation time. An alternative faster than Monte Carlo method is analytical error propagation by means of a Taylor series expansion; however, this approach suffers from being explained in the literature in conflicting ways, hampering implementation in most software packages for LCA. The purpose of this paper is to compare the two different approaches from a theoretical and practical perspective.Methods
In this paper, we compare the analytical and sampling approaches in terms of their theoretical background and their mathematical formulation. Using three case studies—one stylized, one real-sized, and one input–output (IO)-based—we approach these techniques from a practical perspective and compare them in terms of speed and results.Results
Depending on the precise question, a sampling or an analytical approach provides more useful information. Whenever they provide the same indicators, an analytical approach is much faster but less reliable when the uncertainties are large.Conclusions
For a good analysis, analytical and sampling approaches are equally important, and we recommend practitioners to use both whenever available, and we recommend software suppliers to implement both. 相似文献12.
Mingming Hu René Kleijn Kossara P. Bozhilova-Kisheva Francesco Di Maio 《The International Journal of Life Cycle Assessment》2013,18(9):1793-1803
Purpose
The framework of life cycle sustainability analysis (LCSA) has been developed within the CALCAS project but the procedure on how an LCSA should be carried out is still far from standardized. The purpose of this article is to propose an approach to put the LCSA framework into practice. This approach is illustrated with an on-going case study on concrete recycling.Methods
In the context of an EC-FP7 project on technology innovation for concrete recycling, five operational steps to implement the LCSA framework are proposed: (1) broad system definition, (2) making scenarios, (3) defining sub-questions for individual tools, (4) application of the tools and (5) interpreting the results in an LCSA framework. Focus has been put on the goal and scope definition (steps 1–3) to illustrate how to define a doable and meaningful LCSA. Steps 4–5 are not complete in the case study and are elaborated theoretically in this paper.Results and discussion
The experience from the case study shows that the operational steps are especially useful at the stage of defining the goal and scope. Breaking down the sustainability questions into different scales and different aspects gives the possibility to define the sub-questions suitable to be assessed by the individual analytical tools (e.g., LCA, LCC, SLCA, MFA, etc.). The C2CA-LCSA shows a practical approach to model the life cycle impacts of the broad system is to start by modelling the technological system at the micro level and then scale it up with the realistic scenario settings that are generated with the knowledge gained from the MFA studies at the meso-level and from the policy/economic studies at the macro level. The combined application of LCA, LCC and SLCA at the project level shows not all the cost items and only one social impact indicator can be modelled in the process-based LCA structure. Thus it is important to address the left out information at the interpretation step.Conclusions
Defining sub-questions on three different levels seems most useful to frame an LCSA study at the early stage of goal and scope definition. Although this study provides some useful steps for the operationlisation of the LCSA concept, it is clear that additional case studies are needed to move LCSA into a practical framework for the analysis of complex sustainability problems. 相似文献13.
泛函连接网络计算软件及其在生物多样性研究中的应用 总被引:14,自引:0,他引:14
针对农田生物多样性分析的需要,研制出泛函连接网络(FLANN)计算软件。该软件由7个Java类和1个HTML文件组成,是一种Internet在线计算工具,可运行于多种操作系统和Web浏览器上,并在各种类型的PC及工作站上使用,可读取多种类型的数据库文件。对水稻田昆虫生物多样性的两组取样调查数据Zmar18和Zapr15,用生物多样性工具软件LUMP和非监督分类-离差平方和聚类法进行统计归纳及分类,分别划分为21个和20个功能群,各包含60个样本。以FLANN计算软件对昆虫生物多样性进行了模式分类分析。结果表明,泛函连接网络的模式分类及预测与实际测查结果吻合良好。泛函连接网络Internet在线计算软件的应用可促进生物多样性数据采集和分析的规范化,有利于数据和信息共享,也为形成高度的生物多样性智能分析系统提供了一种工具。 相似文献
14.
Ulrike Fillinger Khadija Kannady George William Michael J Vanek Stefan Dongus Dickson Nyika Yvonne Geissbühler Prosper P Chaki Nico J Govella Evan M Mathenge Burton H Singer Hassan Mshinda Steven W Lindsay Marcel Tanner Deo Mtasiwa Marcia C de Castro Gerry F Killeen 《Malaria journal》2008,7(1):1-25
Background
As the population of Africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed.Methods
A recently initiated Urban Malaria Control Programme in Dar es Salaam delegates responsibility for routine mosquito control and surveillance to modestly-paid community members, known as Community-Owned Resource Persons (CORPs). New vector surveillance, larviciding and management systems were designed and evaluated in 15 city wards to allow timely collection, interpretation and reaction to entomologic monitoring data using practical procedures that rely on minimal technology. After one year of baseline data collection, operational larviciding with Bacillus thuringiensis var. israelensis commenced in March 2006 in three selected wards.Results
The procedures and staff management systems described greatly improved standards of larval surveillance relative to that reported at the outset of this programme. In the first year of the programme, over 65,000 potential Anopheles habitats were surveyed by 90 CORPs on a weekly basis. Reaction times to vector surveillance at observations were one day, week and month at ward, municipal and city levels, respectively. One year of community-based larviciding reduced transmission by the primary malaria vector, Anopheles gambiae s.l., by 31% (95% C.I. = 21.6–37.6%; p = 0.04).Conclusion
This novel management, monitoring and evaluation system for implementing routine larviciding of malaria vectors in African cities has shown considerable potential for sustained, rapidly responsive, data-driven and affordable application. Nevertheless, the true programmatic value of larviciding in urban Africa can only be established through longer-term programmes which are stably financed and allow the operational teams and management infrastructures to mature by learning from experience. 相似文献15.
Carbon intensity targets, namely carbon emissions per unit of GDP, are used as macro-level indicators of low carbon performance at the province- and city-level in China. However, this measure is too aggregated to provide a meaningful indication of low carbon performance and inform practical management strategies. Most traditional low carbon city indicators have no direct relationship with national carbon intensity reduction targets and do not provide municipal government administrators with the practical information they need to inform low carbon development at the local level. This paper integrates city-level carbon intensity targets with a low carbon city indicator system by means of a decomposed method to offer a better approach for carbon intensity reduction performance evaluation. Using Xiamen as a case study, one of the NDRC's low-carbon project areas, a target integrated indicator system is presented, including indicator values which have been determined through scenario analysis and calculation. The indicators and values can help local municipal governments to meet their carbon intensity reduction targets by providing an indication of current performance and identifying sectors where there is scope for further improvement. The methodology provides the theoretical basis and reference values for the evaluation of a city's low carbon performance within the context of achieving a carbon reduction target, thereby enhancing the potential for scientific and operational evaluation at the local level. 相似文献
16.
《Genetic analysis, techniques and applications》1996,12(3-4):151-162
Hybridization to sets of bacterial colonies or PCR products arrayed on high density filters is used in a number of experimental schemes. In many cases it is desirable to collect quantitative information (‘hybridization signatures’) rather than indications on ‘positive’ and ‘negative’ colonies. We present a practical system, based on an imaging plate analyser and a customized version of commercial software, that makes such quantification feasible, and define its performance in terms of reproducibility and linearity. The system is far superior to methods based on autoradiography and should be useful in many projects that involve the increasingly popular high density filter format. 相似文献
17.
Giorgio Luigi Valentini Walter Lassonde Samee Ullah Khan Nasro Min-Allah Sajjad A. Madani Juan Li Limin Zhang Lizhe Wang Nasir Ghani Joanna Kolodziej Hongxiang Li Albert Y. Zomaya Cheng-Zhong Xu Pavan Balaji Abhinav Vishnu Fredric Pinel Johnatan E. Pecero Dzmitry Kliazovich Pascal Bouvry 《Cluster computing》2013,16(1):3-15
Two major constraints demand more consideration for energy efficiency in cluster computing: (a) operational costs, and (b) system reliability. Increasing energy efficiency in cluster systems will reduce energy consumption, excess heat, lower operational costs, and improve system reliability. Based on the energy-power relationship, and the fact that energy consumption can be reduced with strategic power management, we focus in this survey on the characteristic of two main power management technologies: (a) static power management (SPM) systems that utilize low-power components to save the energy, and (b) dynamic power management (DPM) systems that utilize software and power-scalable components to optimize the energy consumption. We present the current state of the art in both of the SPM and DPM techniques, citing representative examples. The survey is concluded with a brief discussion and some assumptions about the possible future directions that could be explored to improve the energy efficiency in cluster computing. 相似文献
18.
Using higher organisms in biological early warning systems for real-time toxicity detection. 总被引:3,自引:0,他引:3
W H van der Schalie T R Shedd P L Knechtges M W Widder 《Biosensors & bioelectronics》2001,16(7-8):457-465
Many biological early warning systems (BEWS) have been developed in recent years that evaluate the physiological and behavioral responses of whole organisms to water quality. Using a fish ventilatory monitoring system developed at the US Army Centre for Environmental Health Research as an example, we illustrate the operation of a BEWS at a groundwater treatment facility. During a recent 12-month period, the fish ventilatory system was operational for 99% of the time that the treatment facility was on-line. Effluent-exposed fish responded as a group about 2.8% of the time. While some events were due to equipment problems or non-toxic water quality variations, the fish system did indicate effluent anomalies that were subsequently identified and corrected. The fish monitoring BEWS increased treatment facility engineers' awareness of effluent quality and provided an extra measure of assurance to regulators and the public. Many operational and practical considerations for whole organism BEWS are similar to those for cell- or tissue-based biosensors. An effective biomonitoring system may need to integrate the responses of several biological and chemical sensors to achieve desired operational goals. Future development of an 'electronic canary', analogous to the original canary in the coal mine, could draw upon advances in signal processing and communication to establish a network of sensors in a watershed and to provide useful real-time information on water quality. 相似文献
19.
追踪天使——雷达昆虫学30年 总被引:20,自引:3,他引:20
雷达昆虫学是一门新的学科分支。从它诞生起的30年来,英、美、澳、中四国的观测研究已初步阐明了昆虫在迁飞过程中的成层、定向、集聚等行为现象及其时空分布,揭示了大气结构和运动对昆虫迁飞的影响,为深化人们对昆虫迁飞行为机制的认识提供了许多令人耳目一新的画面;昆虫雷达技术也逐渐从研究走向实用,已经实现了对迁飞性害虫的长期、自动和实时监测。在全国建立VLR网并与GIS相结合,可望实现对我国重大虫灾的及时预警。 相似文献
20.
Evans-Pritchard's The Nuer not only served as the paradigm of "segmentary lineage systems," but it also inspired a wide range of ethnographic literature which contributed to the elaboration of "descent theory." The Nuer ethnography was reanalyzed many times and most recently it was declared that the "segmentary lineage system" constituted a "representational model" only, quite different from the actors' "operational rules" (Holy 1979a). Despite the remarkable insight that it proved in the formation of Nuer local groups and the mechanics of Nuer politics, Holy's analysis falls short of a satisfactory reinterpretation of the Nuer polity for those interested in comparison because it restricted itself to local groups and failed to tackle the Nuer concepts of buth, thok dwiel and mar, central to Evans-Pritchard's interpretation. By relegating lineages to the status of "representation," Holy further obscures the course of comparative analysis since he does not provide any criterion to discover when lineages belong to the "representational" or the "operational" levels. Using a different conceptual framework, it is demonstrated that the groups which Evans-Prit chard interpreted as lineages are not "representations" but are in fact defined around cattle. It is concluded that the Nuer simply did not have any lineages, segmentary or not. 相似文献