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181.
Anaerobic co-digestion of organic wastes from households, slaughterhouses and meat processing industries was optimised in a half technical scale plant. The plant was operated for 130 days using two different substrates under organic loading rates of 10 and 12 kgCOD.m(-3).d(-1). Since the substrates were rich in fat and protein components (TKN: 12 g.kg(-1) the treatment was challenging. The process was monitored on-line and in the laboratory. It was demonstrated that an intensive and stable co-digestion of partly hydrolysed organic waste and protein rich slaughterhouse waste can be achieved in the balance of inconsistent pH and buffering NH4-N. In the first experimental period the reduction of the substrate COD was almost complete in an overall stable process (COD reduction >82%). In the second period methane productivity increased, but certain intermediate products accumulated constantly. Process design options for a second digestion phase for advanced degradation were investigated. Potential causes for slow and reduced propionic and valeric acid degradation were assessed. Recommendations for full-scale process implementation can be made from the experimental results reported. The highly loaded and stable codigestion of these substrates may be a good technical and economic treatment alternative.  相似文献   
182.
In the UK, 1950-75 was a lively period in the long-running debates between proponents of absorption and marginal costing. In the nexus of competing interests, management accountants advocated and defended rival costing systems with much vigour and passion. Expressed in the language of the times, these debates were 'battles' in the costing 'war'. We focus on these battles, analysing the various forces that operated upon the combatants, and locate them in the wider costing war. We conclude that no final resolution of the conflict was achieved in the twentieth century, nor is one likely in the foreseeable future.  相似文献   
183.
This article tests three common budgetary decision–making theories in the US states. Pooled time series cross–section analysis is used from 1960 to 1996 to test the garbage can theory and incrementalism, and from 1989 to 1996 to test various theories of rational budgeting. The results demonstrate that there was some support for all three theories in terms of their impact on reducing state budget outputs. Rational budgeting reduces expenditures in aggregate, incrementalism has relatively low explanatory power below the aggregates, and garbage can budgeting is more prevalent in functional areas than for government as a whole. These findings imply that the future research agenda on budgetary decision–making theories should focus more on a system–wide approach, which takes into account many of the characteristics of all three rival models of decision–making, rather than exclusively focusing on each one singly.  相似文献   
184.
The primary objective of this project is to identify gaps, whether real or perceived, that hinder effective groundwater management in New Zealand. These gaps show as gaps in information, gaps in implementation, gaps in technological and management tools, and gaps in understanding of fundamental processes. The secondary objective is to propose a management strategy to close the identified gaps. Several methods are used to meet these objectives: surveys distributed to selected staff in each regional council; the review of various written reports; the analysis of land-use databases; and private consultation within each regional council. Results show that groundwater management in New Zealand is generally reactionary with the main gaps being in strategic planning and national guidelines. Most gaps appear to be predominantly information and implementation issues. In some cases there are gaps in the understanding of fundamental processes within an aquifer system, including the long-term effects of land-use on groundwater quality. An adaptive management approach is suggested as a means of closing these gaps.  相似文献   
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186.
The effects of competitive interactions on investment decisionsand on the dynamics of the price of a nonstorable commodityare studied in a model of incremental investment with time tobuild and operating flexibility. I find that an increase inuncertainty may encourage firms to increase their capacity.Furthermore, I show that it may be optimal to invest in additionalcapacity during periods in which part of the operational capacityis not being utilized. The impact of competition on the propertiesof the endogenous output price is dramatic. For example, I findthat price volatility may be increasing in the number of competitorsin the industry.  相似文献   
187.
The paper examines the relationship between transitory terms‐of‐trade shocks and private saving. Using a model allowing for nonseparability between the consumption of tradables and nontradables, the paper estimates the intertemporal elasticity of substitution while accounting for the intratemporal elasticity of substitution between the consumption of tradables and nontradables. Empirical analysis of data for five industrial countries indicates that in response to transitory terms‐of‐trade shocks, intertemporal substitution of consumption and intratemporal substitution of consumption between tradables and nontradables both have large effects on private saving.  相似文献   
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189.
The American Psychological Association Task Force recommended that researchers always report and interpret effect sizes for quantitative data. However, no such recommendation was made for qualitative data. Thus, the first objective of the present paper is to provide a rationale for reporting and interpreting effect sizes in qualitative research. Arguments are presented that effect sizes enhance the process of verstehen/hermeneutics advocated by interpretive researchers. The second objective of this paper is to provide a typology of effect sizes in qualitative research. Examples are given illustrating various applications of effect sizes. For instance, when conducting typological analyses, qualitative analysts only identify emergent themes; yet, these themes can be quantitized to ascertain the hierarchical structure of emergent themes. The final objective is to illustrate how inferential statistics can be utilized in qualitative data analyses. This can be accomplished by treating words arising from individuals, or observations emerging from a particular setting, as sample units of data that represent the total number of words/observations existing from that sample member/context. Heuristic examples are provided to demonstrate how inferential statistics can be used to provide more complex levels of verstehen than is presently undertaken in qualitative research.  相似文献   
190.
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