Natural Disposability Research Articles

An Empirical Study on Agricultural Product Distribution Technology by Means of ICT Convergence

When it comes to the high distribution cost ratio of agricultural products, the major causes include lack of competition among distribution channels and inefficiency of distribution steps in addition to inevitable aspects such as the large volume and weight compared to the price, distance between producers and consumers, advanced types of consumption, gradual decomposition, and natural spoilage, the last two of which are primary factors that increase the distribution cost ratio. In general, agricultural products are vulnerable to supply shock, and thus price fluctuation rates are higher than those of industrial products. In particular, vegetables and fruits, which are difficult to keep fresh for a long period of time and easily affected by weather conditions, are of high price fluctuation rates. For these reasons, it is of urgent need to come up with ways to minimize natural spoilage and disposal in distribution of agricultural products. The suggested system provides various functions : a function to predict weight reduction of products during the storage and distribution process based on the analysis of data collected by the server to judge the level of quality deterioration.

Industrial Energy and Environment Efficiency of Chinese Cities: An Analysis Based on Range-Adjusted Measure

Industrial energy and environment efficiency evaluation is essential in guiding national and environmental policy making, since the industrial sector is the largest energy consumer and major pollutants producer in China. This study utilizes the Range-Adjusted Measure (RAM)-based models to evaluate the energy and environment efficiency of industrial sectors in 31 Chinese major cities. The empirical results show that eastern Chinese cities outperform their western counterparts in terms of industrial energy efficiency, and central Chinese cities outperform their eastern counterparts in terms of industrial environment efficiency. Under natural disposability, 23 cities exhibit decreasing returns to scale, and under managerial disposability, 18 cities exhibit increasing damages to scale.

Investment strategy for sustainable society by development of regional economies and prevention of industrial pollutions in Japanese manufacturing sectors

A balance between industrial pollution prevention and economic growth becomes a world-wide issue to develop a sustainable society in many industrial nations. To discuss the issue, this study proposes a new use of DEA environmental assessment to determine how to effectively allocate capital for developing regional industries. The amount of capital is used to invest for technology innovation for both local economic growth and environmental protection. In this study, the proposed approach separates outputs into desirable and undesirable categories. Inputs are also separated into two categories, one of which indicates an amount of investment on capital assets. The other category is used for production activities. The proposed approach unifies them by two disposability concepts. This study has evaluated the performance of manufacturing industries in 47 prefectures (local government units in Japan) by Unified Efficiency under Natural disposability (UEN), Unified Efficiency under Managerial disposability (UEM) and Unified Efficiency under Natural and Managerial disposability (UENM). The UENM is further separated into its two cases: with and without a possible occurrence on desirable congestion, or technology innovation, on undesirable outputs. This study has empirically confirmed that Japanese manufacturing industries need to make their efforts to reduce greenhouse gas emissions and air pollution substances by investing in technology innovation. Furthermore, most of economic activities are currently located at metropolitan regions (e.g., Tokyo) in Japan. To develop a sustainable society, Japan needs to allocate capital into regions with a high level of investment effectiveness by shifting the manufacturing industries from the metropolitan regions to much promising local areas identified in this study. Such a shift, along with technology innovation, makes it possible to reduce air pollutions in the entire Japan by balancing economic growth and pollution prevention. This empirical study confirms that the proposed approach is useful in both guiding regional planning and developing a sustainable society. It is easily envisioned that the proposed approach is useful for not only Japan but also the other industrial and developing nations.

DEA (Data Envelopment Analysis) assessment of operational and environmental efficiencies on Japanese regional industries

A balance between industrial pollution and economic growth becomes a major policy issue to attain a sustainable society in the world. To discuss the problem from economics and business perspectives, this study proposes a new use of DEA (Data Envelopment Analysis) as a methodology for unified (operational and environmental) assessment. A unique feature of the proposed approach is that it separates outputs into desirable and undesirable categories. Such separation is important because energy industries usually produce both desirable and undesirable outputs. This study discusses how to unify the two types of outputs under natural and managerial disposability. The proposed DEA approach evaluates various organizations by the three efficiency measures such as OE (Operational Efficiency), UEN (Unified Efficiency under Natural disposability) and UENM (Unified Efficiency under Natural and Managerial disposability). An important feature of UENM is that it separates inputs into two categories and unifies them under the two disposability concepts in addition to the proposed output separation and unification. This study incorporates an amount of capital assets for technology innovation, as one of the two input group, into the measurement of UENM. Then, it compares UENM with the other two efficiency measures. This study is the first research effort in which DEA has an analytical capability to quantify the importance of investment on capital assets for technology innovation. To confirm the practicality of the proposed approach, this study applies the three efficiency measures to a data set regarding manufacturing and non-manufacturing industries of 47 prefectures in Japan. This study empirically confirms the validity of Porter hypothesis in Japanese manufacturing industries, so implying that environmental regulation has been effective for betterment on the performance of Japanese manufacturing industries. Another important finding is that the emission of greenhouse gases is a main source of unified inefficiency in the two groups of industries. Therefore, Japanese industries, examined in this study, need to make their efforts to reduce the greenhouse gas emissions and air pollution substances by investing in capital assets for technology innovation.

DEA radial measurement for environmental assessment: A comparative study between Japanese chemical and pharmaceutical firms

Climate change and various pollutants have been influencing our societies and economies. Recently, many individuals, firms and public entities (e.g., the United Nations) are interested in environmental protection (e.g., reduction of CO2 emission). This study discusses a use of DEA (Data Envelopment Analysis) to measure unified (operational and environmental) efficiency by considering energy utilization and environmental protection. A DEA model used in this study belongs to the radial measurement whose frontier is shaped by the Debreu-Farrell type of efficiency measure. In applying DEA to environmental assessment, it is necessary for us to classify outputs into desirable and undesirable categories because private and public entities usually produce the two types of outputs as a result of their economic activities. After the classification, it is necessary for us to unify between desirable and undesirable outputs and then to incorporate the concept of natural and managerial disposability into DEA. Furthermore, this study theoretically explores how to measure the type of RTS (Returns to Scale) under natural disposability and how to measure the type of DTS (Damages to Scale) under managerial disposability. Such scale measures are quantitatively explored under two disposability concepts. As an illustrative application, this study compares between Japanese chemical and pharmaceutical firms in terms of their unified efficiency measures and the type of RTS/DTS. This study finds two empirical implications. One of the two implications is that approximately 50% of firms in the two groups belong to decreasing RTS. Therefore, it is recommended that they should reduce their corporate sizes to enhance the operational performance. The other implication is that 59.5% of chemical firms, belonging to increasing DTS, should reduce their sizes to reduce their environmental performance. Alternatively, this study recommends that they should introduce new environmental technology to reduce an amount of their undesirable outputs. The technology innovation on undesirable outputs has more practicality than the scale decrease for the chemical firms.

A comparative study among fossil fuel power plants in PJM and California ISO by DEA environmental assessment

This study compares among fossil fuel power plants in PJM and California ISO by their unified (operational and environmental) performance. DEA (Data Envelopment Analysis) is used as a methodology. For comparative analysis, DEA incorporates strategic concepts such as natural and managerial disposability into the computational process. This study explores both how to measure Returns to Scale (RTS) under natural disposability and how to measure Damages to Scale (DTS) under managerial disposability. This empirical study obtains two implications on US energy policy. One of the two policy implications is that California ISO outperforms PJM in terms of the three unified efficiency measures. The result implies that strict regulation on undesirable outputs, as found in California, is important in enhancing the performance of US fossil fuel power plants. Thus, it is necessary for federal and local governments to regulate the fossil fuel power plants under the strict implementation of environmental protection. Under such a policy direction, it is possible for US fossil fuel power plants to attain economic prosperity (by enhancing their operational efficiencies) and to satisfy environmental regulation (by enhancing their environmental efficiencies). The other policy implication is that coal-fired and gas-fired power plants in PJM and California ISO need to reduce their operational sizes or introduce technology innovation on desirable and undesirable outputs and/or new management for environmental protection within their operations. Meanwhile, oil-fired power plants may increase their operational sizes if they can introduce technology innovation and new management on undesirable outputs.

China’s regional energy and environmental efficiency: A Range-Adjusted Measure based analysis

Energy and environmental efficiency evaluation has recently attracted increasing interest in China. In this study, we utilize the Range-Adjusted Measure (RAM) based nonparametric approach to evaluate the regional energy and environmental efficiency of China over the period of 2006–2010. The desirable/good and undesirable/bad outputs, as well as the energy and non-energy inputs are considered in the efficiency evaluation so as to characterize the energy consumption, economic production, and CO2 emission process of different China’s regions. In addition, the economic concepts of natural disposability and managerial disposability are incorporated in the evaluation instead of the strong and weak disposability in conventional environmental efficiency evaluation. Therefore, the types of returns to scale and damages to scale of different China’s regions are measured and correspondingly the strategy and policy implications are proposed for guiding the future improvement of regional energy and environmental efficiency. This study finds that: (i) Beijing, Shanghai, and Guangdong had the highest integrated energy and environmental efficiency during the study period, which could be seen as the benchmarks of inefficient China’s regions. (ii) On average, east China had the highest integrated efficiency under natural disposability, and west China had the highest integrated efficiency under managerial disposability. (iii) During 2006–2010, the average production efficiency of China slightly decreased and the average emission efficiency of China slightly increased. (iv) Among China’s 30 regions, 19 regions exhibited decreasing returns to scale, 4 regions shown increasing returns to scale, and 7 regions have mixed returns to scale types under natural disposability in our study period. In addition, under managerial disposability, there are 18, 3 and 9 regions respectively exhibited increasing, decreasing and mixed damages to scale types over time. (v) For most Chinese regions, it is not recommended to simply increase or maintain their current scales of production, but alternatively, they should pay more attentions on technology innovation of energy utilization efficiency improvement, since up to 2010, China still had large energy conservation and emission reduction potentials.

DEA environmental assessment: Measurement of damages to scale with unified efficiency under managerial disposability or environmental efficiency

This study proposes a use of Data Envelopment Analysis (DEA) for environmental assessment. Firms usually produce not only desirable but also undesirable outputs as a result of their economic activities. The concept of disposability on undesirable outputs is separated into natural and managerial disposability. Natural disposability is an environmental strategy in which firms decrease their inputs to reduce a vector of undesirable outputs. Given the reduced input vector, they attempt to increase desirable outputs as much as possible. Managerial disposability involves the opposite strategy of increasing an input vector. The concept of disposability expresses an environmental strategy that considers a regulation change on undesirable outputs as a new business opportunity. Firms attempt to improve their unified (operational and environmental) performance by utilizing new technology and/or new management. Considering the two disposability concepts, this study discusses how to measure unified efficiency under managerial disposability and then discusses how to measure environmental efficiency. The proposed uses of DEA can serve as an empirical basis for measuring new economic concepts such as “Scale Damages (SD)”, corresponding to scale economies for undesirable outputs, and “Damages to Scale (DTS)”, corresponding to returns to scale for undesirable outputs.

Vibrational Stark Effects in the Active Site of Ketosteroid Isomerase Point to Large Electric Fields Driving Chemical Catalysis

Enzymes are extraordinary catalysts that actuate nearly all biomolecular processes with speed and specificity. Nevertheless, the physical origins of enzymes’ catalytic power remain elusive despite investigations of many enzymes’ mechanisms over the last half-century. Ketosteroid isomerase (KSI) is a small and proficient enzyme - accelerating an isomerization reaction ∼1 trillion-fold over its intrinsic rate in water - that has been employed as a test system to examine the catalytic strategies at Nature's disposal. Electrostatic interactions are broadly purported to play an essential role in catalysis, but this proposal has yet to be experimentally tested in a quantitative fashion. Toward this end, vibrational Stark effect spectroscopy provides a toolkit to measure electric fields in biomolecular environments. By measuring the vibrational Stark effect of an intrinsic probe that mimics the reactive species of KSI's catalytic cycle, we found that KSI's active site focuses an extremely large electric field onto the scissile bond, potentially enabling its speedy chemical conversion through electrostatic interactions. Moreover, we observed a strong correlation between active site electric field and catalytic power across several KSI mutants. These studies are building toward a highly reductionist picture of KSI's catalysis and possibly enzyme catalysis in general.

Returns to scale and damages to scale on U.S. fossil fuel power plants: Radial and non-radial approaches for DEA environmental assessment

This study proposes a new use of Data Envelopment Analysis (DEA) for environmental assessment, paying attention to a methodological bias (i.e., different methods produce different results). DEA is analytically classified into radial and non-radial approaches. The radial approach determines the level of unified (operational and environmental) efficiency by measuring an inefficiency score. The score indicates the distance of a projection from an observed performance to an efficiency frontier. In contrast, the non-radial approach determines the level of unified efficiency by measuring a total amount of slacks because each slack indicates inefficiency. To avoid the methodological bias, this study considers the use of radial and non-radial approaches. In this study, we consider a production process where all organizations produce not only desirable (good) but also undesirable (bad) outputs as a result of their business operations. To unify the two types of outputs, this study discusses the concept of disposability, which is separated into natural and managerial disposability. The natural disposability indicates negative adaptation to a regulation change on undesirable outputs. In contrast, the managerial disposability indicates corporate strategy by which a firm considers the regulation change as a new business opportunity. A firm attempts to improve its unified efficiency by utilizing new environmental technology and/or new management. This type of strategy indicates positive adaptation to the regulation change. Under the two disposability concepts, this study discusses how to measure RTS (Returns to Scale) under natural disposability and DTS (Damages to Scale: corresponding to RTS on undesirable outputs) under managerial disposability. The two scale measures are analytically discussed by the proposed radial and non-radial approaches with SCSCs or without SCSCs, where SCSCs indicate strong complementary slackness conditions. An illustrative example on U.S. fossil fuel power plants indicates a policy implication that they need to introduce new technology for environmental protection. This study also discusses a necessity of examining a methodological bias in energy studies. Empirical findings identified in this study document the practicality of the proposed approaches to measure RTS/DTS.

DEA environmental assessment of coal fired power plants: Methodological comparison between radial and non-radial models

This study discusses how to apply Data Environment Analysis (DEA) for environmental assessment. A unique feature of DEA environmental assessment is that it classifies outputs into desirable (good) and undesirable (bad) outputs because many firms often produce not only desirable outputs but also undesirable outputs as a result of their economic activities. A methodological difficulty of DEA applications is how to combine operational performance on desirable outputs and environmental performance on undesirable outputs in a unified treatment. Although previous DEA environmental studies have utilized mainly radial models and their extensions, this study uses a non-radial DEA model for the output unification because the non-radial model can unify the two types of outputs more easily than the radial models. This study incorporates three types of output unification in DEA environmental assessment. The first unification considers both an increase and a decrease in an input vector along with a decrease in the direction vector of undesirable outputs. This type of unification measures “unified efficiency”. The second unification considers a decrease in an input vector along with a decrease in the vector of undesirable outputs. This type of unification is referred to as “natural disposability” and measures “unified efficiency under natural disposability”. The third unification considers an increase in an input vector but a decrease in the vector of undesirable outputs. This type of unification is referred to as “managerial disposability” and measures “unified efficiency under managerial disposability”. All the unifications increase the vector of desirable outputs. Using the output unification under natural and managerial disposability, this study examines methodological strengths and drawbacks of the proposed non-radial approach. Moreover, using a data set on U.S. coal fired power plants, we compare methodological strengths and drawbacks of radial and non-radial models for DEA environmental assessments. The methodological comparison is important in guiding a large energy issue because policy implications depend upon a methodology(s) used for an empirical study.

Returns to Scale and Damages to Scale with Strong Complementary Slackness Conditions in DEA Assessment: Japanese Corporate Effort on Environment Protection

This study proposes a use of Data Envelopment Analysis (DEA) for environmental assessment. All organizations in private and public sectors produce not only desirable (good) but also undesirable (bad) outputs as a result of their economic activities. The proposed use of DEA determines the level of unified (operational and environmental) efficiency of all the organizations. A contribution of this study is that it explores how to measure not only RTS (Returns to Scale) on desirable outputs but also a new concept regarding “DTS: Damages to Scale” (corresponding to RTS for undesirable outputs). This study discusses how to measure RTS under natural disposability and DTS under managerial disposability by DEA. The measurement of RTS and DTS is formulated by incorporating “Strong Complementary Slackness Conditions (SCSCs)”. As a result, this study can handle an occurrence of multiple reference sets and multiple projections in the RTS/DTS measurement. The incorporation of SCSCs makes it possible both to restrict DEA multipliers in a specific range without any prior information and to identify all possible efficient organizations as a reference set. Using the unique capabilities of SCSCs, this study discusses the use of DEA environmental assessment by exploring how to classify the type of RTS/DTS with SCSCs. Such analytical capabilities are essential, but not previously explored in DEA environmental assessment for energy industries. As an illustrative example, this study applies the proposed approach for the performance evaluation of Japanese manufacturing industries. This study finds that these firms need to introduce technology innovation to reduce an amount of greenhouse gases and wastes. The empirical result confirms the importance of measuring RTS/DTS in DEA environmental assessment.

Returns to Scale, Damages to Scale, Marginal Rate of Transformation and Rate of Substitution in DEA Environmental Assessment

This study discusses a new use of DEA (Data Envelopment Analysis) environmental assessment to measure MRT (Marginal Rate of Transformation) and RS (Rate of Substitution) between desirable and undesirable outputs. To discuss MRT and RS, this study first examines a concept of disposability from the perspective of corporate strategies to adapt a regulation change on undesirable outputs. The concept of disposability is separated into natural and managerial disposability. Then, this study explores the computational framework of RTS (Returns to Scale) and DTS (Damages to Scale). The type of RTS is measured within the natural disposability, while the type of DTS is measured within the managerial disposability. Considering the two types of disposability, this study discusses MRT and RS between desirable and undesirable outputs. As an illustrative example, this study applies the proposed approach to evaluate the performance of US coal-fired power plants. This study finds that the regulation policy on NOx and SO2 has been effective on their emission controls under US Clean Air Act (CAA). The regulation on CO2, or a major source of the global warming and climate change, is still insufficient in the United States. Therefore, this study recommends that US federal and local governments should regulate the amount of CO2 emission under the CAA.

DEA radial and non-radial models for unified efficiency under natural and managerial disposability: Theoretical extension by strong complementary slackness conditions

This study proposes a use of Data Envelopment Analysis (DEA) for environmental assessment. All radial and non-radial models are discussed under natural and managerial disposability. The natural disposability implies corporate strategy by which a firm attempts to decrease an input vector to decrease a vector of undesirable outputs. Given the decreased input vector, a firm attempts to increase a vector of desirable outputs as much as possible. This type of strategy, supported by economists, indicates negative adaptation to a regulation change on undesirable outputs. In contrast, the managerial disposability indicates opposite strategy by increasing the input vector. This disposability expresses corporate strategy by which a firm considers the regulation change as a new business opportunity. A firm attempts to improve its performance by utilizing new environmental technology and/or new management. This type of strategy, supported by corporate strategists in U.S. business schools, indicates positive adaptation to the regulation change on undesirable outputs. Using the proposed DEA assessment, this study examines the relationship among energy consumption, economic development and environmental protection in Japanese prefectures. To theoretically extend the use of DEA for environmental assessment, this study incorporates Strong Complementary Slackness Conditions (SCSCs) into the proposed radial models. The incorporation of SCSCs has three methodological strengths. First, DEA/SCSCs can handle an occurrence of multiple reference sets and multiple projections. Second, the incorporation of SCSCs makes it possible to restrict dual variables (multiples) in a specific range without any prior information. Finally, DEA/SCSCs can bypass the conventional procedure (i.e., a radial model combined with an additive model) used for DEA radial measurement.

DEA radial measurement for environmental assessment and planning: Desirable procedures to evaluate fossil fuel power plants

Energy policy depends on a proper use of methodology in guiding a large energy issue such as the global warming and climate change. DEA is one of such methodologies that are often used for preparing environmental policy, which is closely linked to various energy issues. Unfortunately, the use of DEA applied to environmental policy is insufficient, often misguiding policy makers and other individuals who are involved in energy issues. This study provides three guidelines for a use of DEA in preparing environmental assessment. First, it is important to prepare both primal and dual formulations to confirm whether information regarding all production factors (i.e., inputs, desirable and undesirable outputs) is fully utilized in DEA assessment. Second, DEA has model variations in radial and non-radial measurements. It is necessary for us to examine environmental issues by different models in order to avoid a methodological bias existing in those empirical studies. Finally, DEA environmental assessment needs to incorporate the concept of natural and managerial disposability. The natural disposability indicates that a firm negatively adapts a regulation change on undesirable outputs. In contrast, the managerial disposability indicates that a firm positively adapts the regulation change because the firm considers the regulation change as a new business opportunity.

Weak and strong disposability vs. natural and managerial disposability in DEA environmental assessment: Comparison between Japanese electric power industry and manufacturing industries

The economic concept of weak and strong disposability has long dominated studies on DEA (Data Envelopment Analysis) environmental assessment. This study reviews the two disposability concepts from their conceptual and methodological implications. In particular, this study is interested in the concept of weak disposability because the concept is believed to have an analytical capability to measure an occurrence of “congestion”. The two economic concepts on disposability, accepted by production economists, are replaced by natural and managerial disposability in this study. The natural disposability implies an environmental strategy by which a firm attempts to decrease an input vector to reduce a vector of undesirable outputs. Given the decreased input vector, a firm attempts to increase a vector of desirable outputs as much as possible. This type of strategy indicates negative adaptation. In contrast, the managerial disposability indicates an opposite strategy by increasing the input vector. This disposability expresses an environmental strategy by which a firm considers a regulation change as a new business opportunity. A firm attempts to improve its unified performance by utilizing new clean air technology and/or new management. The strategy indicates positive adaptation. Considering the two groups of disposability, this study compares between weak/strong disposability and natural/managerial disposability in terms of their conceptual and methodological differences, focusing upon the concept of congestion and technology innovation. Furthermore, using the concept of natural and managerial disposability, this study compares Japanese electric power firms with manufacturing firms. This study finds that the manufacturing firms outperform the electric power firms under natural disposability. An opposite result is found under managerial disposability. This empirical study also finds that the two groups of Japanese firms have attained desirable (good) congestion due to technology innovation. Based upon such empirical results, this study identifies two policy implications. One of the two implications is that the two groups of Japanese industries have attained a high level of technology innovation by a result of environmental regulation. The other is that the electric power industry operates more efficiently to reduce the CO2 emission than the manufacturing industries.

Environmental assessment by DEA radial measurement: U.S. coal-fired power plants in ISO (Independent System Operator) and RTO (Regional Transmission Organization)

The economic concept of weak and strong disposability on undesirable outputs dominated the previous discussions on DEA (Data Envelopment Analysis) radial measurement for environmental assessment. This study reexamines the economic concept from the perspective of corporate strategies on how to adapt a regulation change on undesirable outputs. The economic concept of disposability, conventionally accepted by production economists, is replaced by natural and managerial disposability in this study. The natural disposability implies an environmental strategy that a firm attempts to decrease an input vector to reduce a vector of undesirable outputs. Given the decreased input vector, the firm attempts to increase a vector of desirable outputs as much as possible. This type of strategy indicates negative adaptation. Meanwhile, the managerial disposability indicates an opposite strategy by increasing the input vector. This disposability expresses an environmental strategy by which a firm considers a regulation change on undesirable outputs as a new business opportunity. A firm attempts to improve its unified (operational and environmental) performance by utilizing new technology and/or new management. The strategy indicates positive adaptation. Considering the two types of disposability, this study discusses how to measure unified efficiency under natural and managerial disposability by DEA radial models. To document the practicality of the proposed DEA environmental assessment, this study applies it to compare the performance of U.S. coal-fired power plants under ISOs/RTOs (Independent System Operators/Regional Transmission Organizations) with that of the other power plants not belonging to any organization. This study identifies two empirical findings. One of the two findings is that the latter coal-fired power plants outperform the former power plants belonging to ISOs/RTOs in terms of three efficiency measures. This result indicates that ISOs and RTOs do not provide an effective coordination for coal-fired power plants at the level that can be found in the other power plants. The other finding is that there is technological improvement in the operation of coal-fired power plants.

Data envelopment analysis for environmental assessment: Comparison between public and private ownership in petroleum industry

Environmental assessment recently becomes a major policy issue in the world. This study discusses how to apply Data Envelopment Analysis (DEA) for environmental assessment. An important feature of the DEA environmental assessment is that it needs to classify outputs into desirable (good) and undesirable (bad) outputs because private and public entities often produce not only desirable outputs but also undesirable outputs as a result of their production activities. This study proposes the three types of unification for DEA environmental assessment by using non-radial DEA models. The first unification considers both an increase and a decrease in the input vector along with a decrease in the direction vector of undesirable outputs. This type of unification measures “unified efficiency”. The second unification considers a decrease in an input vector along with a decrease in the vector of undesirable outputs. This type of unification is referred to as “natural disposability” and measures “unified efficiency under natural disposability”. The third unification considers an increase in an input vector but a decrease in the vector of undesirable outputs. This type of unification is referred to as “managerial disposability” and measures “unified efficiency under managerial disposability”. All the unifications increase the vector of desirable outputs. To document their practical implications, this study has applied the proposed approach to compare the performance of national oil firms with that of international oil firms. This study identifies two important findings on the petroleum industry. One of the two findings is that national oil companies under public ownership outperform international oil companies under private ownership in terms of unified (operational and environmental) efficiency and unified efficiency under natural disposability. However, the performance of international oil companies exhibits an increasing trend in unified efficiency. The other finding is that national oil companies need to satisfy the environmental standard of its own country while international oil companies need to satisfy the international standard that is more restricted than the national standards. As a consequence, international oil companies outperform national oil companies in terms of unified efficiency under managerial disposability.

Returns to scale and damages to scale under natural and managerial disposability: Strategy, efficiency and competitiveness of petroleum firms

Environmental assessment recently becomes a major policy issue all over the world. This study discusses how to use Data Environment Analysis (DEA) for environmental assessment for planning corporate strategy and international competitiveness. An important feature of DEA environmental assessment is that it classifies outputs into desirable (good) and undesirable (bad) outputs because all private and public entities produce not only desirable outputs but also undesirable outputs as a result of their production activities. This study proposes the two types of output unification for DEA environmental assessment by using a non-radial model. One of the two output unifications is that it considers a decrease in an input vector along with a decrease in the vector of undesirable outputs. This type of unification is referred to as “natural disposability”. The other unification considers an increase in an input vector but a decrease in the vector of undesirable outputs. This type of strategy is referred to as “managerial disposability”. Both unifications increase the vector of desirable outputs. After developing the two concepts on disposability, this study theoretically explores how to measure Returns to Scale (RTS) under natural disposability and Damages to Scale (DTS) under managerial disposability. To document the practicality of the proposed approach, this study applies it to compare the performance of national oil firms with that of international oil companies. This study identifies four important findings on the petroleum industry. First, national oil companies outperform international oil companies in the unified efficiency under natural disposability. Second, international oil companies outperform national oil companies in the unified efficiency under managerial disposability. Third, national oil firms exhibit a mixed result on RTS, while international oil firms exhibit decreasing RTS. Finally, both national and international oil companies exhibit increasing DTS, implying that all oil firms need to decrease their operational sizes for improving their environmental performance on CO2 emission. As an alternative strategy, the result suggests that they need to introduce technology innovation (e.g. clean air technology) into their business operations. The technology based strategy has more practicality than the size reduction in their operations.

Maturity indices of Indian horse-chestnut (Aesculus indica Colebr.) seeds under temperate Kashmir conditions

Our study on maturity indices of Aesculus indica Colebr. seeds was conducted under temperate Kashmir conditions in 2006. Seed collection was started from 15 July and continued until the maturation of seeds in December. The seeds were harvested fortnightly from identified trees and on each collection date maturity indices, viz. seed color, seed weight, moisture content, seed dimension, specific gravity and germination percentage were recorded. The study revealed that at the time of maturity (Nov.-Dec.) the seed color was a shiny chocolate brown, with a moisture content of 58.37% and a specific gravity of 0.82. Germination was maximum (80%) at its maturity with a maximum seed weight of 52.03 g per seed. We recommend that the seeds should be collected before their natural disposal.