Groundwater balance and conservation under different water pricing and agricultural policy scenarios: A case study of the Hamadan-Bahar plain

Government subsidies for agricultural activities in recent decades have encouraged farmers of Hamadan-Bahar plain to extend the number of wells and irrigated farms, with no consideration of groundwater resource conservation. As a result, the level of the groundwater table has decreased continuously in this area, threatening the life of groundwater aquifer. The objective of the study is to analyze the impacts of irrigation water pricing and agricultural policy scenarios on aquifer conservation by considering the dynamic relations between aquifer groundwater balance and the agriculture sector. For this purpose a combination of simulation and optimization techniques is considered in a dynamic framework. Firstly, dynamic treatments of groundwater and the main factors affecting the balance of studied aquifer are simulated. Then, optimization behaviour of agriculture sector related to farmers' decision-making processes is defined on the time horizon. Thereafter all of the equations are used simultaneously by a non-linear dynamic programming method, which maximize present value of gross margins of agriculture sector subject to groundwater constrains and other input limitations. The analysis of the results indicates that water pricing by itself can considerably reduce the agricultural demand for aquifer groundwater in the Hamadan-Bahar plain.     

Predicting capacity utilization: Federal Reserve vs time-series models

This study evaluates the Federal Reserve forecasts of manufacturing capacity utilization employing, as benchmarks, the forecasts from a univariate model which utilizes past information in capacity utilization, and from a bivariate model which utilizes past information in both capacity utilization and the federal funds rate. In addition to accurately predicting the directional change in capacity utilization, the Federal Reserve forecasts are “weakly” rational and generally superior to the bivariate forecasts. In light of another finding that monetary policy is non-neutral, we argue the Federal Reserve forecasts of capacity utilization have positively contributed to the Fed’s success in maintaining a low inflationary environment.

Scheduling of re-entrant flow shops

We propose and develop a scheduling system for a very special type of flow shop. This flow shop processes a variety of jobs that are identical from a processing point of view. All jobs have the same routing over the facilities of the shop and require the same amount of processing time at each facility. Individual jobs, though, may differ since they may have different tasks performed upon them at a particular facility. Examples of such shops are flexible machining systems and integrated circuit fabrication processes. In a flexible machining system, all jobs may have the same routing over the facilities, but the actual tasks performed may differ; for instance, a drilling operation may vary in the placement or size of the holes. Similarly, for integrated circuit manufacturing, although all jobs may follow the same routing, the jobs will be differentiated at the photolithographic operations. The photolitho-graphic process establishes patterns upon the silicon wafers where the patterns differ according to the mask that is used.The flow shop that we consider has another important feature, namely the job routing is such that a job may return one or more times to any facility. We say that when a job returns to a facility it reenters the flow at that facility, and consequently we call the shop a re-entrant flow shop. In integrated circuit manufacturing, a particular integrated circuit will return several times to the photolithographic process in order to place several layers of patterns on the wafer. Similarly, in a flexible machining system, a job may have to return to a particular station several times for additional metal-cutting operations.These re-entrant flow shops are usually operated and scheduled as general job shops, ignoring the inherent structure of the shop flow. Viewing such shops as job shops means using myopic scheduling rules to sequence jobs at each facility and usually requires large queues of work-in-process inventory in order to maintain high facility utilization, but at the expense of long throughput times.In this paper we develop a cyclic scheduling method that takes advantage of the flow character of the process. The cycle period is the inverse of the desired production rate (jobs per day). The cyclic schedule is predicated upon the requirement that during each cycle the shop should perform all of the tasks required to complete a job, although possibly on different jobs. In other words, during a cycle period we require each facility to do each task assigned to it exactly once. With this requirement, a cyclic schedule is just the sequencing and timing on each facility of all of the tasks that that facility must perform during each cycle period. This cyclic schedule is to be repeated by each facility each cycle period. The determination of the best cyclic schedule is a very difficult combinatorial optimization problem that we cannot solve optimally for actual operations. Rather, we present a computerized heuristic procedure that seems very effective at producing good schedules. We have found that the throughput time of these schedules is much less than that achievable with myopic sequencing rules as used in a job shop. We are attempting to implement the scheduling system at an integrated circuit fabrication facility.     

To Help or Not to Help? The Good Samaritan Effect and the Love of Money on Helping Behavior

This research tests a model of employee helping behavior (a component of Organizational Citizenship Behavior, OCB) that involves a direct path (Intrinsic Motives → Helping Behavior, the Good Samaritan Effect) and an indirect path (the Love of Money → Extrinsic Motives → Helping Behavior). Results for the full sample supported the Good Samaritan Effect. Further, the love of money was positively related to extrinsic motives that were negatively related with helping behavior. We tested the model across four cultures (the USA., Taiwan, Poland, and Egypt). The Good Samaritan Effect was significant for all four countries. For the indirect path, the first part was significant for all countries, except Egypt, whereas the second part was significant for Poland only. For Poland, the indirect path was significant and positive. The love of money may cause one to help in one culture (Poland) but not to help in others. Results were discussed in the light of ethical decision making.

The economics of conflicts of interest in financial institutions

A conflict of interest exists when a party to a transaction can gain by taking actions that are detrimental to its counterparty. This paper examines the growing empirical literature on the economics of conflicts of interest in financial institutions. Economic analysis shows that, although conflicts of interest are omnipresent when contracting is costly and parties are imperfectly informed, there are important factors that mitigate their impact and, strikingly, it is possible for customers of financial institutions to benefit from the existence of such conflicts. The empirical literature reaches conclusions that differ across types of conflicts of interest but are overall more ambivalent and certainly more benign than the conclusions drawn by journalists and politicians from mostly anecdotal evidence.     

An elementary proposition on technical progress and non-traded goods

We explore the effect of technical progress on the endogenously determined range of non-traded goods by using a Ricardian model with continuum of goods. By defining technical progress on the basis of proportional changes in the relative productivity across sectors, we show that the range of non-traded goods decreases if technical progress is unbiased or if it is biased toward the goods that a country has more comparative advantage.     

North–South Trade Liberalization and Economic Welfare

We consider a general equilibrium model of a developing economy (the South) that opens to trade with a developed economy (the North). The southern economy is characterized by open urban unemployment and rural–urban migration, a competitive agricultural sector and a monopolistically competitive manufacturing sector. Hence, there is potential for both inter‐ and intra‐industry trade to arise on liberalization, in addition to distortionary effects of duality. Southern comparative advantage in agriculture may arise from the labor market distortion and the basis for intra‐industry trade is love for variety. We characterize various configurations of the trade pattern, and the resulting welfare consequences of opening to trade in this context. We illustrate a new mechanism under which in some circumstances it may be possible for trade liberalization to lower economic welfare in the South.     

Johnson's algorithm: A key to solve optimally or approximately flow shop scheduling problems with unavailability periods

Johnson's algorithm (JA) is perhaps the most classical algorithm in the scheduling area. JA gives the optimal solution to the two machine flow shop to minimize the makespan in polynomial time. Researchers have tried to extend this notorious result to obtain polynomial time algorithms for more general cases. Such importance motivated us to devote this paper to JA applied to three flow shop problems with unavailability periods to minimize the makespan. First we focus on the optimality condition of JA. Then we propose a modification of JA. After we calculate new performances of JA as a heuristic. Last we deal with an extension of JA.     

Equity Control of Multinational Firms: Effects on Resource Allocation and National Welfare

In this paper, we re-examine the effects of equity control of multinational firms on resource allocation and national welfare in a model with rural–urban migration and urban unemployment. A large number of recipient (host) countries are developing countries with dual economies. We indicate, among other things, that a restriction on multinational investment may lower the unemployment rate and increase the total employment in the host country. Furthermore, we find that the restriction on multinational investment raises the national welfare in the host economy if the tariff imposed on imports is sufficiently large and the difference between domestic and foreign capital rental is sufficiently small.