Thermoelectric materials: a new rapid synthesis process for non-toxic and high-performance tetrahedrite compounds

The feasibility to synthesize, in large quantity, pure and non-toxic tetrahedrite compounds using high-energy mechanical-alloying from only elemental precursors is reported in the present paper for the first time. Our processing technique allows a better control of the final product composition and leads to high thermoelectric performances (ZT of 0.75 at 700 K), comparable to that reported on sealed tube synthesis samples. Combined with spark plasma sintering, the production of highly pure and dense samples is achieved in a very short time, at least 8 times shorter than in conventional liquid-solid-vapor synthesis process. The process described in this paper is a promising way to produce high performance tetrahedrite materials for cost-effective and large-scale thermoelectric applications.

EVA : economic value added : resumo e aplicação da metodologia

Faz uma exposição da metodologia EVA®, demonstrando sua aplicação no gerenciamento da empresa e na avaliação de seu desempenho. Particularmente, mostra sua utilidade como no ferramenta de aferição e incentivo de seus dirigentes, bem como de seu uso em decisões de investimento e desinvestimento

Study of the measurement of value-added

Includes bibliography

Modifying Fences to Prevent Ungulate Use of Cropland and High-Value Pastures

Big game can damage crops and compete with livestock for valuable forage. Ranchers have reported their tolerance for big game would increase if the animals could be prevented from using key areas critical for spring livestock use. Likewise, some farmers have high value areas that must be protected. Fences provide the most consistent long term control compared to other deterrent methods, but are costly to erect. Many designs of woven wire and electric fences are currently used. Costs of erecting deer proof fencing could be greatly reduced if an existing fence could be modified instead of being replaced entirely. This study investigates the possibility of modifying existing fences to prohibit deer and elk crossings. Preliminary results indicate effective modifications can be made to existing fences for $1300- $3500 per mile for materials. Traditional complete construction of game fences cost more than $10,000 per mile. These fences may be used in lieu of compensation programs for ranchers. Also, if farmers and ranchers can keep big game out of important foraging areas, their tolerance for these animals on the rest of their property may greatly increase.

New ruralities – old gender dynamics?: A reflection on high-value crop agriculture in the light of the feminisation debates

While a remarkable continuity in smallholder agricultural production has been identified, the shift from subsistence orientation towards more wage dependence appears in a different light when analysed under a gender perspective. "Feminisation" has been a catchphrase to characterise some of these processes; however, the debate has been subject to overgeneralisation, and can only inadequately grasp the gender dynamics in what has been referred to as "new ruralities". Illustrated for high-value crop production as an expression of agricultural transition in the Global South, this contribution offers a critical account of the feminisation thesis. Instead of discarding the notion of feminisation, it advocates a reassessment of its potential as a comprehensive framework against which empirical findings can be reflected. While conventional uses of the feminisation thesis have, in their great majority, come up with the conclusion that for women it can always only get worse, I propose a perspective which reveals gains and risks and how they are shared between men and women as they engage in new agricultural labour markets. This perspective rests on a methodology for case-based, comparative studies developed in this paper as a contribution for assessing the nature of agricultural transition and to investigate the qualitative change associated with new ruralities. A distinctive appreciation of the substance of agricultural change for different members of the rural society – namely men and women, but also different men, and different women – is the premise for overcoming barriers to shared development, and for framing effective governance in the context of global development.

Seasonal variation of high-molecular-weight compounds in the water-soluble fraction of organic urban aerosols

Aerosol samples were collected in Zurich, Switzerland, at an urban background site and were analyzed with size exclusion chromatography (SEC) and laser/desorption ionization mass spectrometry (LDI-MS) for water-soluble organic compounds with high molecular weight. Daily samples were collected during two campaigns in winter and summer, for 1 month each. The concentration of high-molecular-weight compounds (humic-like substances (HULIS)) was between 0.4 and 4 μg/m3 in winter and summer. The most intense signals in the LDI-MS mass spectra were measured between m/z150 and 500, comparing well with the mode of the two main high mass peaks determined with SEC corresponding to masses between 200 and 600 Da. For the maximum molecular weight, however, different results were obtained by the two techniques: whereas a maximum molecular weight between 1300 and 3300 Da was found with SEC, hardly any peaks above m/z700 were measured with LDI-MS. During summer the maximum molecular weight of HULIS (determined with SEC) correlates positively with several parameters such as ozone and increased temperature indicative of enhanced atmospheric photo-oxidation. The HULIS concentration also correlates positively with the oxalic acid concentration in the particles. This suggests that HULIS are generated by secondary processes in summer. The lack of such correlations during winter suggests that other sources and processes might be important during colder seasons.

The Problem with Value-Added Measurement

Measuring student learning through standardized tests is a lot harder than modern education reformers would have you believe.

Input-output-based genuine value added and genuine productivity in China's industrial sectors (1995-2010)

The rapid growth of China's economy has brought about huge losses of natural capital in the form of natural resource depletion and damages from carbon emissions. This paper recalculates value added, capital formation, capital stock, and related multifactor productivity in China's industrial sectors by further developing the genuine savings method of the World Bank. The sector-level natural capital loss was calculated using China's official input–output table and their extensions for tracing final consumers. The capital output elasticity in the productivity estimation was adjusted based on these tables. The results show that although the loss of natural capital in China's industrial sectors in terms of value added has slowed, the impacts on their productivity during the past decades is still quite clear.

Production fragmentation, upstreamness, and value-added : evidence from factory Asia 1990-2005

We exploit the recent release of the 2005 Asian Input-Output Matrix to dress a picture of the geographic fragmentation of value added in Factory Asia from 1990 to 2005. We document 3 stylized facts. The first is that the average share of foreign value added embedded in production rose by about 7 percentage points between 1990 and 2005, from 9% to 16%. The second is that, contrary to popular belief, China's production embeds a smaller share of foreign value added than other Factory Asia countries'. Between 1990 and 2005 among Factory Asia countries China grew most after Japan as a source of value added to other countries' production. Third, country-industries at the upstream and downstream extremities of the supply chain embed a smaller share of foreign value added than those with intermediate levels of upstreamness.

Heckscher-Ohlin : evidence from virtual trade in value added

The fragmentation of production chains across borders is one of the most distinctive feature of the last 30 years of globalization. Nonetheless, our understanding of its implications for trade theory and policy is only in its infancy. We suggest that trade in value added should follow theories of comparative advantage more closely than gross trade, as value-added flows capture where factors of production, e.g. skilled and unskilled labor, are used along the global value chain. We find empirical evidence that Heckscher-Ohlin theory does predict manufacturing trade in value-added, and it does so better than for gross shipment flows. While countries exports across a broad range of sectors, they contribute more value-added in techniques using their abundant factor intensively.

A unified framework of trade in value added : physical, monetary, exchange rates, and GHG emissions

Koopman et al. (2014) developed a method to consistently decompose gross exports in value-added terms that accommodate infinite repercussions of international and inter-sector transactions. This provides a better understanding of trade in value added in global value chains than does the conventional gross exports method, which is affected by double-counting problems. However, the new framework is based on monetary input--output (IO) tables and cannot distinguish prices from quantities; thus, it is unable to consider financial adjustments through the exchange market. In this paper, we propose a framework based on a physical IO system, characterized by its linear programming equivalent that can clarify the various complexities relevant to the existing indicators and is proved to be consistent with Koopman's results when the physical decompositions are evaluated in monetary terms. While international monetary tables are typically described in current U.S. dollars, the physical framework can elucidate the impact of price adjustments through the exchange market. An iterative procedure to calculate the exchange rates is proposed, and we also show that the physical framework is also convenient for considering indicators associated with greenhouse gas (GHG) emissions.