Ghosh Model Research Articles

Absence of Local Conserved Quantity in the Heisenberg Model with Next-Nearest-Neighbor Interaction

We rigorously prove that the S=1/2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$S=1/2$$\\end{document} anisotropic Heisenberg chain (XYZ chain) with next-nearest-neighbor interaction, which is anticipated to be non-integrable, is indeed non-integrable in the sense that this system has no nontrivial local conserved quantity. Our result covers some important models including the Majumdar–Ghosh model, the Shastry–Sutherland model, and many other zigzag spin chains as special cases. These models are shown to be non-integrable while they have some solvable energy eigenstates. In addition to this result, we provide a pedagogical review of the proof of non-integrability of the S=1/2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$S=1/2$$\\end{document} XYZ chain with Z magnetic field, whose proof technique is employed in our result.

Influence of Sb doping on thermal properties and electrical conductivity mechanism of SbxSe50–xSn20Te30 chalcogenide glassy systems

Tunability of thermal, and electrical characteristics of SbxSe50-xSn20Te30 (x = 2, 4, 6, and 8 at. %) bulk glass systems with varying doping concentrations are the major objective of this study. The melt quenching technique has been employed to synthesize the samples. Various thermal parameters have been inspected by using DSC measurements. The effect of Sb addition on the glass transition temperature (Tg), crystallization temperature (Tc), peak crystallization temperature (Tp), and melting temperature (Tm) have been observed from DSC thermograms. The dependence of Tg, Tc, Tp, and Tm on the heating rate has been measured. The thermal analysis is performed under non-isothermal conditions at heating rates of 5, 10, 15, and 20 K/min. The activation energies for the glass transition temperature are estimated by using the Kissinger method and are found to decrease from (211.21-168.85) KJ.mol−1. Thermal stability and glass forming ability for all glassy compositions have been examined in terms of Hruby's parameter. In addition, electrical conductivity mechanisms over vast temperature and frequency ranges are analyzed. The DC conductivity mechanism has been analyzed by deploying Mott and Greaves's variable range hopping model, while the AC conductivity mechanism has been analyzed by deploying the modified correlated barrier hopping model. AC conductivity scaling property has been examined by using the Pan and Ghosh model. The influence of Sb addition has been observed as the DC and AC conductivity increases with the increase of doping concentration.

Temperature Dependence of the Thermo-Optic Coefficient of SiO2 Glass.

This paper presents a thorough analysis on the temperature dependence of the thermo-optic coefficient, dn/dT, of four bulk annealed pure-silica glass samples (type I-natural quartz: Infrasil 301; type II-quartz crystal powder: Heraeus Homosil; type III-synthetic vitreous silica: Corning 7980 and Suprasil 3001) from room temperature down to 0 K. The three/four term temperature dependent Sellmeier equations and respective coefficients were considered, which results from fitting to the raw data obtained by Leviton et al. The thermo-optic coefficient was extrapolated down to zero Kelvin. We have obtained dn/dT values ranging from 8.16 × 10-6 up to 8.53 × 10-6 for the four samples at 293 K and for a wavelength of 1.55 μm. For the Corning 7980 SiO2 glass, the thermo-optic coefficient decreases monotonically, from 8.74 × 10-6 down to 8.16 × 10-6, from the visible range up to the third telecommunication window, being almost constant above 1.3 μm. The Ghosh's model was revisited, and it was concluded that the thermal expansion coefficient only accounts for about 2% of the thermo-optic coefficient, and we have obtained an expression for the temperature behavior of the silica excitonic bandgap. Wemple's model was also analyzed where we have also considered the material dispersion in order to determine the coefficients and respective temperature dependences. The limitations of this model were also discussed.

Input-output price indexes: forgoing the Leontief and Ghosh models

ABSTRACT In input-output analysis, the Leontief and Ghosh models can be used to determine the price indexes of goods, which is convenient for analyzing inter-industry inflation. Their respective merits are debated, but both provide the same solution. We demonstrate that, contrary to common belief, it is superfluous to use the Leontief or Ghosh model to calculate price indexes: the price index vector alone satisfies the accounting identities without assuming constant coefficients. So, in contrast to the Leontief and Ghosh models, price indexes can be derived ‘instantly’, without a round-by-round process. Conducting research on price indexes deduce from the Leontief or Ghosh model becomes pointless: it suffices to study price indexes deduced from the data. We illustrate these findings with an application for France 2018. The same is demonstrated for prices with the data given in physical quantities.

A supply-driven model consuming simultaneously all primary inputs: unfolding analytical potential beyond the Ghosh model

The Ghosh model fails to endogenise the simultaneous consumption of primary inputs and, consequently, is unused. It is argued that this limitation stems from being specified mirroring the Leontief model. In particular, primary inputs are considered homogeneous and independent despite being heterogeneous and (intersectorally) dependent. A new supply-driven model endogenising the consumption of all primary inputs except the one driving the model is developed. It displays new features: structural linearity and structural variability. An input multiplier analysis illustrates that the new model's total requirements matrix represents the actual structure of the economy, overcoming the Ghosh model's ‘limitation’. Also, it is exemplified how to use complementary information from the Ghosh model to deepen structural analyses. Thus, this paper solves a long-lasting theoretical inconsistency in IO modelling and unfolds new analytical potential, hopefully rekindling the interest in supply-driven analyses.

Thermal efficiency of metal foams on pool boiling

This paper presents an experimental work on pool boiling using HFE-7100 at saturated conditions, under atmospheric pressure, and copper and nickel foams as the heating surface with four different thicknesses varying between 0.5 mm and 3 mm, followed by an analysis of the effect of foam fin-efficiency based on Ghosh model. All foams showed a better heat transfer coefficient (HTC) than the plain surface; however, as the heat flux increased, the HTC from the thicker nickel foams decreased due to the bubble vapor flow inside the foam. On the other hand, the thinner nickel foam showed better HTC at high heat fluxes with a maximum enhancement of 120%. The foam efficiency presented a similar tendency with the HTC, i.e., as the thickness decreases the efficiency increases; however, as compared with copper foams with a similar area but different porous diameter, the copper foams are 40% more efficient than the nickel ones due to the foam material, which has a thermal conductivity 4.5 times higher.

Transportation, storage and GHG emissions: A new perspective of input-output subsystem analysis

We develop an input–output subsystem analysis based on the Ghosh model to study the emissions of a sector given the productive structure of the economy. Our method complements the traditional subsystem analysis based on the demand-driven model by considering the emissions associated to the primary inputs of the subsystem. This is particularly relevant to study the emissions associated to the activity of sectors that produce mainly for other sectors. We apply both methodologies to analyze the transportation and storage subsystem emissions in Spain in 2014. The outcomes from the demand-driven model point to land and air transport as the main responsible for subsystem emissions, while the supply-driven model also considers storage sector as significant in explaining the subsystem emissions. When intermediate demand is relevant, the consideration of both models helps to better identify the activities responsible for the subsystem emissions, allowing for more accurate policy recommendations.

Модифікація структури моделі Гоша в міжгалузевому аналізі

The current Ghosh model is based on the use of value-added forecast data. The forecasts of gross domestic product and value added have long and regularly been developed by different national and international economic and financial structures, including governmental ones. The level of methods and accuracy of such forecasts is quite high as compared with the final demand forecasts on which the Leontief model is based. Therefore, from the econometric point of view, the accuracy of predictions of output made by using the Ghosh model should be at least not worse than that provided by the classical Leontief model. The modified Ghosh model formally differs from its current model by the presence of a new matrix. However, this difference is only a structural feature, and in mathematical terms these models are identical. At the same time, the modified Ghosh model is more attractive and promising than the current one due to the following factors. It uses one matrix instead of two matrices that appear in the current model. The modified model has a structure (unlike the current one) similar to the structure of the classical Leontief model. Due to this, the modified model is more understandable and easy to use. However, the most important feature lies in the fact that the use of a new matrix significantly expands the possibilities of theoretical research within the input-output structures. Due to constructing a new matrix in the modified Ghosh model, new relations between the vectors of final demand and value added were discovered, which can be efficiently used in balancing the system of input-output matrices. It was also established that the corresponding matrices of the classical Leontief model and the modified Ghosh model have identical diagonal elements in pairs, and this is useful in various analytical studies. Keywords: modified Ghosh model, input-output, Leontief model, value added, final demand

Structural analysis of inter-industrial linkages: an application to the Australian construction industry

With the rapid growth in economic and technological development, the linkage of the construction industry with the economy has changed in the past decades, which may have generated corresponding changes in other industries. This study sheds new light on the measurement of structural changes in the inter-industrial linkages of an industry using the Leontief model and the Ghosh model based on the hypothetical extraction method. The Australian national input–output tables provided in the World Input–Output Database are employed as an empirical study exploring the influence of construction linkages on other industries’ production input and output. The results indicate that construction effects have become weaker in relation to promoting economic growth, although the mining and quarrying industry and some service industry activities demonstrate strong and positive backward and forward linkages with the construction industry in Australia. This research provides an approach for measuring corresponding changes in other industries caused by one industry’s inter-industrial changes.

A follow-up note on the plausibility of the Leontief and Ghosh closed models

ABSTRACTHerein we consider Leontief and Ghosh models that partly endogenize both part of final demand and part of value-added. We use Osterhaven's [(2012) Adding Supply-driven Consumption Makes the Ghosh Model Even More Implausible. Economic Systems Research, 24, 101–111] numerical three-sector example to show that anomalies of the sort he finds for a Ghosh closed model can also be found in the closed version of a Leontief model. By assuming, as Oosterhaven did, that aggregate exogenous resources are fixed, we obtain mirror results to his in a Ghosh setting, albeit in the more-traditional Leontief instance. Such numerical anomalies for the three-sector case turn out to be generic to both partially closed models for any 2×2 input–output model. A proof for the general n×n case remains to be uncovered.

A Nonlinear Supply-Driven Input-Output Model

One of the major limitations of the supply-driven input-output (I-O) Ghosh model concerns its linear production function. Using the I-O table, this paper replaces the linear production function with the Cobb-Douglas (CD) production function within the supply-driven model. The two models are compared both theoretically and empirically. Nonlinear production function, relative substitutability of primary factors, and variability of the proportion of intermediate inputs over product levels are the characteristics of the proposed model. The consideration of sectors' Solow residual as Total Factor Productivity (TFP) of sectors is yet another characteristics of the proposed model. The model is also plausible in value added and supply shock computations.

Influence of the post-necking prediction of hardening law on the theoretical forming limit curve of aluminium sheets

This study clarified the influence of the post-necking prediction of the hardening law on the theoretical forming limit curve (FLC) of aluminium sheets subjected to punch-stretching tests. A procedure was developed to identify the parameters of a recently developed hardening model (Kim–Tuan hardening model) based on the curve fitting method. Subsequently, this model was used to capture the post-necking behaviours of two aluminium alloy sheets (AL5052-O and AL6016-T4), which were compared with those of various other hardening models, including the Swift model, Voce model, Hockett–Sherby model, Ghosh model, and a linear combination of the Swift and Voce models. These hardening models, with their extrapolations for post-necking prediction, were employed to analytically calculate the FLCs of the tested materials based on the modified maximum force criterion (MMFC). Furthermore, a simple and effective method was found to estimate the level of limited strain in the plane strain mode, namely FLC0. The proposed method was used to clarify the influence of the hardening law and yield function on the level of the computed FLC. The results indicated that the flow curves predicted by the Kim–Tuan hardening model effectively matched the experimental data obtained from uniaxial tensile tests, while their extrapolations provided intermediate predictions of the post-necking behaviour between the flow curves of the Swift and Voce models. In addition, the proposed hardening model improved the accuracy of the computed FLC for the studied materials.

Capacity of a quantum memory channel correlated by matrix product states

We study the capacity of a quantum channel where channel acts like controlled phase gate with the control being provided by a one-dimensional quantum spin chain environment. Due to the correlations in the spin chain, we get a quantum channel with memory. We derive formulas for the quantum capacity of this channel when the spin state is a matrix product state. Particularly, we derive exact formulas for the capacity of the quantum memory channel when the environment state is the ground state of the AKLT model and the Majumdar–Ghosh model. We find that the behavior of the capacity for the range of the parameters is analytic.

An Empirical Study on the Indirect Impact of Flight Delay on China’s Economy

Due to the influence on the sectors and industries that have strong relationships with the air transportation industry, flight delays have a huge impact on China’s economy. In this study, the input–output method and the Ghosh model were used to analyze the indirect economic impacts of flight delays on China’s economy. We also constructed simultaneous demand-fare equations to estimate the direct output of the air industry as a result of flight delay control. The final results showed that the total indirect impact of flight delays on China was Ұ350.71 billion in 2013, stressing the importance of controlling flight delays. Since delay control not only provides direct benefits to passengers and carriers, but also indirectly contributes to regional economies, the efforts benefit the entire Chinese society. The great investment in flight delay governance should be shared among various producing sectors.

Dependence of tensile ductility on damage evolution of eutectic Si-particles and pre-existing micro-voids in Al-Si casting alloy

The modified constitutive model for predicting the tensile ductility of Al-Si casting alloys was proposed as an extended form in terms of the effective void area fraction that takes into account the geometric configuration and size distribution of pre-existing micro-voids and eutectic Si particles. And, its prediction accuracy was verified through comparison between the theoretical predictions by original Ghosh’s constitutive model and the experimental results of T4-treated A356 alloys. The theoretical prediction by modified constitutive model shows high accuracy which has only a deviation below 10% for the tensile strain of an individual test specimen, compared with a deviation of approximately 40% from the original Ghosh model. The plastic constraint factor and incoherency parameter of the modified constitutive model can effectively describe not only the geometric array and size distribution of micro-voids and eutectic Si-particles but also the additional variation of load-carrying area by damage evolution of Si-particles. The theoretical prediction based upon the largest size of pre-existing micro-void can predict more exactly the overall tensile strain of a material, comparing with a nominal value of average size.

Investigating multi-regional cross-industrial linkage based on sustainability assessment and sensitivity analysis: A case of construction industry in China

Construction industry is one of the most energy-intensive industries, and its output value plays a vital role in economic growth of China. It's expected to be valuable to investigate its sustainability and improvement paths under the background of environment-friendly and conservation-minded development. At first, we adopted a non-radial data envelopment analysis incorporating both natural and managerial disposability to study regional differences regards comprehensive performance of construction industry in China. And then, a multi-regional cross-industrial linkage analysis was carried out embodiment in the sustainable assessment and sensitivity analysis based on the Ghosh model. Accordingly, we intended to provide a systematic relational network focusing on the key provinces and industries which play important roles in improving the comprehensive performance of construction industry. In detail, Hebei, Shanghai, Hubei, Yunnan and Gansu were found to be the most inefficient on account of the results from sustainable assessment in 2007. In accordance with the results from the sensitivity analysis based on the regional input-output model, the adjustment of rationing in mining & processing of ores, manufacture of non-metallic mineral products and smelting & pressing of metals will effectively increase the comprehensive performance of construction industry in the above-mentioned provinces. Emphatically, the method integration used in this study, which could also be applied in other sectors and countries, is a new try to study an industry from the multi-regional and cross-industrial perspective.

Supply-side inoperability input–output model (SIIM) for risk analysis in manufacturing systems

This paper proposes a methodological approach in risk analysis of interdependent manufacturing systems which is based on Ghosh model - a variation of the Leontief input-output model. The proposed approach is able to quantify the impact of supply perturbations in a manufacturing system in terms of cost-price increase in production output due to increase in prices of value-added input brought about by degraded supply resulting from natural or man-made disasters and sudden policy changes. Unlike demand-driven perturbation models presented in literature, the supply-driven inoperability input-output model (SIIM) appears to be more relevant particularly in make-to-order manufacturing systems as demand is usually pre-determined and production costs typically increase when prices of inputs increase. An actual case study was carried out in a furniture manufacturing firm in central Philippines and three scenarios were presented to illustrate the proposed approach: (1) a sudden log ban in the location of the supplier, (2) increase in labor costs and (3) metal shortage caused by severe weather condition. Results show that supply perturbation of upstream processes does not impact downstream processes as long as these processes remain independent of the perturbed upstream process as described in firm's system structure and topology. This also shows that the magnitude of impact of non-perturbed process depends on its nature of interdependence of the perturbed process. The proposed approach is highly relevant for manufacturing practitioners in formulating and implementing mitigation and adaptation policies.

Comparison of Constitutive Relationships of Tubes Established Using Uniaxial Tensile Tests and Tube Hydroforming Experiments

The aim of the present paper is to evaluate existing constitutive models and to fitting hardening laws of SS304 tubes for the accurate prediction of the deformation behaviors of the tubes in hydroforming. Uniaxial tensile test (UTT) and free hydro-bugling (FHB) experiments were conducted on SS304 tubes, and a hi-speed three-dimensional (3D) digital image correlation (DIC) system was applied to obtain the deformation data of the samples. Eight constitutive relationships of the tubes were then established by fitting the equivalent stress and strain data with the four existing constitutive models of Hollomon, Ghosh, Voce and Ghosh/Voce, and the fitting accuracy of the obtained constitutive relationships were analyzed and compared. The results show that Ghosh/Voce model holds the highest accuracy in describing the deformation behaviors of the tubes in UTT and FHB, followed by the Ghosh model and then the Hollomon model. The Voce model holds the lowest accuracy. A distinct discrepancy between the constitutive relationships obtained using UTT and FHB experiments are observed in present research conditions.

Sensitivity analysis of technology and supply change for CO2 emission intensity of energy-intensive industries based on input–output model

Sensitivity analysis based on Leontief model is applied for identifying the key factors leading to the change of CO2 emission or energy consumption in the competitive market from demand perspective. On the other hand, this kind of research from supply-side is also valuable for the economy with characteristics of rationing. Based on previous research achievements, this paper developed out sensitivity analysis based on the Ghosh model. In addition, we implemented sensitivity analysis based on the Leontief and Ghosh model respectively to study the most sensitive factors leading to the change of CO2 emission intensities of the six energy-intensive industries. In terms of 2010 Chinese symmetrical input–output table, the results obtained from the two sensitivity analyses are different. From the demand perspective, the level of production technology in the construction industry plays very important role in the CO2 emission intensity of energy-intensive industries. While, from the supply side, the adjustment of rationing in extraction of petroleum and nature gas should be paid more attention. At last, comparative analysis was carried out and corresponding policy suggestions were put forward. Emphatically, the method used in this paper could be applied to other industries within supply chains of a country, even in the world wide.

Economic and Environmental Impact of National Food Security Act of India

The Government of India has enacted the National Food Security Act (NFSA) on September 12, 2013. The NFSA aims to provide subsidized food grains to approximately two thirds of India’s population. The legislation is a landmark, and perhaps the largest food security program in the world. The ambitious programme of the Government, besides offering several opportunities, throws many challenges in its implementation. In this background, the current paper evaluates the widespread impact of implementing NFSA on the Indian economy. The study applied a modified Leontief and Ghosh model under Input–output framework. The study also assessed the environmental impact of this act focusing on various environmental indicators. Further, the additional land requirement, labour generation and GDP growth that NFSA entails have also been computed. The impacts on sectoral prices have also been calculated. The result shows that the food grain sector has to grow by 3.75 % annually to match provision of food grains according to the norm set by the act. Apart from the targeted food grains sector, we noticed some indirect impact on other sectors such as Chemicals and Chemical Products, Mineral Fuels, Live stock products and Other Oilseeds and Crops. Overall the country needs to gear up in terms of food grain productivity, otherwise, NFSA must be supplemented by import, which would entail huge burden to country’s exchequer. On the other hand, the additional GDP and labour growth is expected to generate 1.51 % and 6.21 % respectively due to NFSA compared to 2016–17. But the impact on the environment is also not favourable. The economy is likely to generate additional GHG emissions of 10.39 million metric tonne of CO2 equivalent due to this act. A significant generation of water pollution is also expected. The overall land requirement on account of NFSA has been found to be sizeable whose availability remains as a big constraint. The study also throws some insight on the achievements of The Millennium Development Goals in the context of NFSA. In the context of Indian sub-continent, we find a perfect synergy between the basic objective of National Food Security Act and Millennium Development Goal. Overall, NFSA impact will enhance the growth of the economy. However, additional pressure on environment and land cannot be ignored. For sustainable food grains production in the economy, the nation should consider the improvement of agriculture productivity as well as to minimize the environmental effect by introducing more sustainable farming practice.