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A Study of Capital Structure of Indian Power Generation and Supply Firms: Unbalanced Panel Data

A Study of Capital Structure of Indian Power Generation and Supply Firms: Unbalanced Panel Data

This paper reveals the determinants of capital structure of power generation and supply firms (PGSFs) in India for the period 1993-2004 using unbalanced panel data. We try for several estimation methods of panel data, random effects estimation technique is selected after using specification tests. The results are similar with earlier studies relating to traditional determinants of capital structure like tangibility, profitability, however signs of variables: size, growth opportunities, cost of borrowing, and liquidity in the firm effects and firm and time effects are correct but not significant. Among the macro-economic variables, inflation and bank development are significantly related with leverage of PGSFs. The findings from the unbalanced panel data model reveal presence of major theories of finance in the case of Indian PGSFs. Further study suggests, focus should be on designing pro-bank and stock market finance policies to overcome the problems faced by PGSFs. This study proposes to offer special treatment to individual and institutional taxpayers in tax rebate for increasing investment in the equity and bonds of PGSFs.

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Analyzing the Kuznets Relationship using Nonparametric and Semiparametric Methods

Analyzing the Kuznets Relationship using Nonparametric and Semiparametric Methods

Abstract: This paper studies the income inequality and economic development relationship by using unbalanced panel data of OECD and non-OECD countries for the period 1962 - 2003. The nonparametric estimation results show that income inequality in OECD countries are almost on the backside of the inverted-U relationship, while non-OECD countries are approximately on the foreside, except that the relationship in both country groups shows an upturn at a high level of development. Development has an indirect effect on inequality through control variables, but the modes are different in the two country groups. The model specification tests show that the relationship is not necessarily captured by the conventional quadratic function. The cubic and fourth-degree polynomials, respectively, fit the OECD and non-OECD country groups best. Our finding is robust regardless whether the specification uses control variables. Development plays a dominant role in mitigating inequality.

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Income Inequality, Poverty, and the Rule of Law: Latin America vs the Rest of the World1

Income Inequality, Poverty, and the Rule of Law: Latin America vs the Rest of the World1

The overall unbalanced panel sample period covers the years 1995 – 2014 for 147 countries, of which seventeen are from Latin America. With the exception of the institutional variables, discussed below, most of the data are available from the World Bank’s World Development Indicators (WDI) collected from various sources. The list of the variables and their sources are in Table 1. For dependent variables, and as a robustness check, I use three different measures of income inequality: the Gini coefficient, Gini ∈ (0, 1) with 1 being the most unequal. An issue with with using the Gini coefficient it is a relative measure that is unable to capture absolute income, thus, it is conceivable that a drop in Gini coincides with a rise in poverty. As such, and as a robustness check, I also use the Palma ratio, which is the ratio of the richest 10% to the poorest 40% income share, this measure, or similar to it, for inequality can be found in a number of studies, such as Gottschalk and Smeeding (2000) and Daly and Wilson (2013). The third inequality variable I use is the intra-time standard deviation of income shares across income quintiles, SD(Share) = P 5

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Technical change and efficiency in Irish agriculture

Technical change and efficiency in Irish agriculture

Abstract: This paper calculates average technical efficiency levels and rates of technical change for Irish agriculture using an unbalanced panel of 2,603 farms drawn from the Irish National Farm Survey over the period 1984 to 1998. An average technical efficiency level of between 65 and 70 per cent with a slight upward trend over the period was found. The efficiency of individual farms is positively associated with the size of the farm household, the ratio of debt to assets and the farmer’s age, and negatively related to being located in the West of Ireland, having an off-farm job and size of farm. Technical progress is observed at an unweighted rate of approximately 0.9 per cent and a weighted rate of 2.1 per cent per annum over the 1984-98 period. There is evidence that this rate of growth has been slowing over time. Technical progress was considerably faster on farms in the East of the country compared to Western farms, on larger farms compared to smaller ones, and on dairy and tillage farms compared to cattle and sheep farms.

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A semiparametric panel model for unbalanced data with application to climate change in the United Kingdom

A semiparametric panel model for unbalanced data with application to climate change in the United Kingdom

This paper is concerned with developing a semiparametric panel model to explain the trend in UK temperatures and other weather outcomes over the last century. We work with the monthly averaged maximum and minimum temperatures observed at the twenty six Meteorological O¢ ce stations. The data is an unbalanced panel. We allow the trend to evolve in a nonparametric way so that we obtain a fuller picture of the evolution of common temperature in the medium timescale. Pro…le likelihood estimators (PLE) are proposed and their statistical properties are studied. The proposed PLE has improved asymptotic property comparing the the sequential two-step estimators. Finally, forecasting based on the proposed model is studied.

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Cervical cancer screening service utilisation in UK.

Cervical cancer screening service utilisation in UK.

Our analysis used 17 years of information, from 1992 to 2008 for the unbalanced panel consisting of 3,758 women and 33,075 observations and for the balanced panel consisting of 857 women and 11,998 observations. In congruence with the cervical screening eligibility guidelines in the UK the analysis differentiate between different age groups of women: age group 16 to 24, age group 25 to 49, age group 50 to 64, age group 65 and older. Provision of cervical cancer screening for the women had to be from NHS to be included in our analysis, because there exists also the possibility of private provision in UK. The dependent variable takes the value of 1 if a cervical cancer screening was done through NHS provision and 0 if no cervical cancer screening was done. Pure private provision as well as provision provided both pri- vately and publicly for cervical cancer screening were excluded in our analysis.

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Inequality and development: Evidence from semiparametric estimation with panel data

Inequality and development: Evidence from semiparametric estimation with panel data

Evidences from nonparametric and semiparametric unbalanced panel data models with fixed effects show that Kuznet’s inverted-U relationship is confirmed when economic development reaches a threshold. The model tests justify semiparametric specification. The integrated net contribution of control variables to inequality reduction is significant.

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A SENSITIVITY ANALYSIS AND AN IMPLEMENTATION OF THE WELLKNOWN VOGEL’S APPROXIMATION METHOD FOR SOLVING UNBALANCED TRANSPORTATION PROBLEM

A SENSITIVITY ANALYSIS AND AN IMPLEMENTATION OF THE WELLKNOWN VOGEL’S APPROXIMATION METHOD FOR SOLVING UNBALANCED TRANSPORTATION PROBLEM

ABSTRACT Though, in the literature, many heuristic approaches were developed in getting an initial solution, VAM (Vogel’s approximation method) is considered to be a better efficient heuristic approach since it often provides an optimal or near optimal solution to the transportation problem. In general, transportation problems involved in supply-chain management fields are unbalanced (total supply > total demand or total supply < total demand) and large-scale problem size. Always, an unbalanced transportation problem is balanced before VAM procedure is applied. But, sometimes, using VAM with unbalanced feature can provide an improved VAM solution. To study this, a sensitivity analysis of VAM has been performed. Based on the sensitivity analysis of VAM, we can conclude that when we solve an unbalanced transportation problem using VAM procedure it is vital to solve the unbalanced transportation problem both ways with balancing and without balancing to get the initial costs of VAM and take the better one as the initial cost to the considered unbalanced transportation problem. Further, in solving large-scale transportation problems, an implementation of VAM is preferred due to time-consuming computations of VAM. In this paper, an attempt has been made to implement the coding of VAM successfully using C++ and compared to the existing coding of VAM from Nabendu Sen et al. [12] via many numerical examples. Based on the results of numerical examples, we can conclude that the correctness of the newly coded VAM is promising as compared with the previously coded one by Nabendu Sen et al. [12].

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Effects of Working Strategy and Duration Variance on Productivity and Work in Process A Simulation-Based Investigation and Oops Game: Cost-Benefits Tradeoff Analysis of Reliable Planning for Construction Activities.

Effects of Working Strategy and Duration Variance on Productivity and Work in Process A Simulation-Based Investigation and Oops Game: Cost-Benefits Tradeoff Analysis of Reliable Planning for Construction Activities.

Improving productivity and reducing work in process (WIP) are two activities that can improve project performance, but are often difficult to accomplish. The construction process is complex and consists of a large number of interdependent and sequential tasks. Construction activities are simulated as serial production lines (SPLs) using STROBOSCOPE to investigate the effects that different working strategies (push/pull and balanced/unbalanced) have on productivity and WIP. The sensitivity to task duration variance is also examined for the different working strategies. The simulation results are used to compare the models based on their performance. Results show that in presence of duration variance, push strategies result in higher productivity, while pull strategies result in lower amounts of WIP. Pull strategies are more sensitive to the presence of duration variance. It is also shown that WIP is a function of the coefficient of variation. The results of simulations are used to compare the tradeoffs between strategies. The findings will help construction managers to better understand the effects of working strategies and conditions to decide which working strategy is best suited for their needs.

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Development of models to study VSC response to AC system faults and the potential impact on network protection

Development of models to study VSC response to AC system faults and the potential impact on network protection

converter to reach its new steady state condition is around 50ms. The output current of the converter is limited to around 1.5 pu in accordance with the limits set in the model. It is also clear that the converter is capable of providing unbalanced fault currents under unbalanced fault conditions. However, neither the response (in terms of both voltage and current) is dissimilar to a conventional synchronous machine output under such fault conditions. Finally, the reactive power injection during the fault from the converter is zero, and therefore the reactive current injection is obviously also zero. This is not in accordance with the requirement of the grid code, therefore further upgrading of the controller (development of fault detection algorithm) should be done to satisfy the grid code.

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Phase Current Control in Grid Connected Photo Voltaic Power Plants to Avoid Over voltages in Healthy Phases

Phase Current Control in Grid Connected Photo Voltaic Power Plants to Avoid Over voltages in Healthy Phases

Since This report needs knowledge of grid voltage angle for the phase current control under unbalanced voltage sags, Phase Locked Loop (PLL) was used which is explained in paper [13]. Moreover the phase currents are defined independently, methods to prevent the controller from trying to inject a zero sequence into the grid further more rescaling the instantaneous current references is proposed to prevent over currents.

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Simulation and Analysis of Single Phase Shunt Active Filter Based on PQ Theory

Simulation and Analysis of Single Phase Shunt Active Filter Based on PQ Theory

The Power Electronic converters and loads are the sources of harmonics and reactive power which greatly affect the performance of the power system network[1].To overcome the problem of power quality, recent efforts have been made on development of better filtering technique. The active filters gathered more concentration because of excellent performance to overcome the harmonic and reactive power problems. But the performance of the active filters depends upon shunt active power filter with controlling done over Instantaneous active and reactive power (P-Q) theory has been purposed to verify its capability and ability to reduce the harmonics [3]. The advantage of p-q theory is that it is instantaneous and it performs in time domain system. The shunt active filter connected to AC distribution system in the presence of different shares of Electronic loads [1] is analyzed. It has been investigated through simulations that even under unbalanced and distorted states of distribution supply voltage and unbalanced loading, shunt active filter is able to mitigate the harmonics (THD) specified by power quality standards the control theory that is employed to formulate the control strategy of the active filter [2].

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Online Full Text

Online Full Text

In general, the inertial continuously variable transmission contains the pulsed mechanism with unbalanced inertial elements, for example, planetary gear with unbalanced satellites, and two overrunning clutches. The main purpose of the pulsed mechanism is to create alternative-sign impulses of the torque. One of the overrunning clutches (the output overrunning clutch) transmits direct impulses of the torque to the output shaft, the other one (the body overrunning clutch) transmits the reverse impulse of the torque on the body of the transmission. The presence of two overrunning clutches determines the possible way for increasing of the reliability of the transmission by reducing the number of the overrunning clutches. For example, the well-known Hobbs’ inertial transmission [1] has only the body overrunning clutch.

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Simulation of Three Phase Soft Starter using Multiple SCRS

Simulation of Three Phase Soft Starter using Multiple SCRS

In this strategy as unbalanced voltage supply is apply to the motor, current flowing throughout it is also unbalanced. To manage the unequal current require to apply firing position α with a remedial position Δα. The nonstop monotonic function between fixed starting and ending points is interpreted as a purpose of the load to be prohibited. The purpose is first empirically single-minded by reproduction process. In this system remedial position is additional with the firing position of phase which contains high current while corrective position is subtracted from the firing position of phase which contains a lesser amount of current. Corrective position can be finding out by equating voltage at motor load. By try and error method we are able to find out the range for the corrective position. The corrective position varies in range of 0˚ to 30˚. At firing angle (α) 0˚ to 60°, a corrective position Δα = 0˚ while at firing position (α) 150° to 180˚, Δα = 30˚. The graph for corrective position Δα is shown in Fig. 4.

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Detection Tool for Unbalanced Bids

Detection Tool for Unbalanced Bids

A literature review was conducted to determine the state-of-the-art in the area of unbalanced bids. In 2004, the American Association of State Highway and Transportation Officials (AASHTO) conducted a survey about how State De- partment of Transportation (DOT) agencies were handling unbalanced bids [8]. A total of 27 State DOTs responded to the survey. The survey results showed that most states did not have any formal procedure to detect unbalanced bids. Florida DOT used a statistical analysis approach to define an acceptable range for each line item price. It also developed a computer program that automatical- ly detects any out of range item price. Texas DOT defined an acceptable range for each line item based on engineering estimates. Then, the possible monthly payments trends of the first and second bidders were computed using the pro- posed bidders’ time schedules. The two trends were then compared to help the evaluators find out unbalanced bids. North Carolina DOT used a contractual provision to prevent unreasonable line item prices. Unit or lump sum prices were considered reasonable and acceptable if they were close to the average of the engineering estimate and other bidder prices. Wang [9] developed a bid- der-based quantitative approach that examined separately every line item price using four tasks, namely, preparation, evaluation, explanation, and adjustment. Arditi and Chotibhongs [10] developed two automated Excel spreadsheet pro- cessing models to detect mathematically and materially unbalanced bids. The models compare the price of each line item against engineering estimates and other bidders’ prices. Shrestha and Joshi [11] conducted a statistical analysis on a historical data set that was collected from 264 bids for 70 road projects to inves- tigate if the submitted bids were unbalanced. Skitmore and Cattell [12] used si- mulation to investigate the impact of two common errors commonly made by bid evaluators. Hyari [13] developed a bid rebalancing model that is based on prevention of unbalanced bids rather than their detection. The model adjusts all line item prices of the lowest bids.

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Multicarrier modulated multi level inverter based DVR and 
		DSTATCOM for mitigating swell

Multicarrier modulated multi level inverter based DVR and DSTATCOM for mitigating swell

unbalanced swells effectively. But, DVR is capable of regulating the voltage more effectively compared to DSTATCOM. It is also observed that the total harmonic distortion in the load voltage is less in case of DVR compared to DSTATCOM and also as the inverter output levels increase; the THD in the load voltage reduces. However, there is not much difference in the injected voltage of 3 level and 5 level inverters. The above technique can be extended for higher levels for further reduction in the THD content.

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Arithmetic of 5th Generation Computer

Arithmetic of 5th Generation Computer

Conversion from decimal to balanced ternary number requires converting the decimal number to unbalanced ternary notation (represented with 0, 1, and 2). Then we have to append a zero before the unbalanced number. The unbalanced ternary is then converted to balanced ternary by adding runs of 1’s i.e 1111… with considering carry, then again from the resultant unbalanced ternary numbers subtract runs of I’s i.e 1111… without considering borrowing (the thing to be noted is that the string of 1s should be of the same length as the ternary numbers, so if the result of the addition has more number of digits, then subtract nothing from these extra digits). In order to add 1s to the unbalanced ternary notation, ternary arithmetic addition operation is performed. The following table 2 shows the basic addition operations performed on ternary arithmetic.

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Cryptanalysis  of  The  Lifted  Unbalanced  Oil  Vinegar  Signature  Scheme

Cryptanalysis of The Lifted Unbalanced Oil Vinegar Signature Scheme

Proposed nearly twenty years ago, the Unbalanced Oil and Vinegar (UOV) scheme still remains unbroken. Further, this simple and elegant signature scheme boasts small signatures and fast signing times. Arguably, the only drawback to UOV is its rather large public key size. The work of Petzoldt mitigates this by generating the pair (( F , T ), P ) from a portion of the public key’s Macaulay matrix and the map T . By choosing this portion to be easy to store, i.e. if it is a cyclic matrix or generated from a pseudo-random number generator, the public key’s bit size can be much reduced [37].

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PI and RST Control Design and Comparison for Matrix Converters Using Venturini Modulation Strategy

PI and RST Control Design and Comparison for Matrix Converters Using Venturini Modulation Strategy

conversion [1]. Interest in this converter topology was rather academic with efforts provided in many research laboratories [1]. MC uses bidirectional current and voltage power switches that connect converter input and output phases [2]. The direct conversion is performed without intermediate DC link circuit for energy storage [2] [3]. MC was introduced firstly in 1976. To prevent the spread of current harmonics caused by the MC to the supply network, an input LC filter is used. It provides a very low impedance path and absorbs current harmonics [1] [2]. Venturini and Alesina proposed a generalized high-frequency switching strategy in 1980 [3]. The objec- tive of this control strategy is to achieve an ideal electronic transformer capable of varying the voltage, current, frequency and power factor [4]. Another method, known as the direct transfer function approach, proposes the multiplication of the input voltages vectors by the modulation matrix M to obtain a vector of output voltages which correspond to a point of synthesis [4]. However, the simultaneous commutation of controlled bidirection- al switches used in MC is very difficult to achieve without generating over current or overvoltage spikes which can destroy the power semiconductors [3]. Also, the load side of the MC is directly affected by the distorted and/or unbalanced input voltages due to the lack of DC intermediate circuit in the MC. The performance of the MC deteriorates, when it is exposed to the harmonic and non-sinusoidal currents and some papers have pre- sented mitigation methods [3] [5]. Conventional PI controller works well only if the mathematical model of the system could be computed. However, it is difficult to implement the conventional PI controller for variable as well as complex systems [5] [6]. So, RST Controller is investigated. This regulator, whose synthesis is purely algebraic, is a sophisticated algorithm based on pole placement method which exploits many numerical re- sources [7] [8]. The method used to determine the gains of the PI controller is the compensation method of poles, we note here that the interest of the compensation of the poles occurs only if the system parameters are accu- rately identified as gains K p and K i are based on these same parameters. If the actual parameters are differ-

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Unbalanced Load Compensation

Unbalanced Load Compensation

Practical systems rarely have perfectly balanced loads, currents, voltages or impedances in all three phases. The analysis of unbalanced cases is greatly simplified by the use of the techniques of symmetrical components. An unbalanced system is analyzed as the superposition of three balanced systems, each with the positive, negative or zero sequence of balanced voltages. In case of unbalance in three phase systems it gives rise to sequence currents i.e positive, negative and zero sequence currents.

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