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Many researchers have examined the relationship between the original equipment manufacturer (OEM) and the third-party remanufacturer (TPR) and found that is mutually beneficial or competitive. This...

Crude oil prices are of vital importance for market participants and governments to make energy policies and decisions. In this paper, we apply a newly proposed autoregressive conditional interval ...

Owing to the convergence of multiple cultures coupled with the unprecedented rapid development in the decades since the late 1990s, the value creation and innovation logic of Asia-Pacific business ...

To seek more business opportunities, cross-market retailers pursue horizontal joint promotion (HJP) to promote their products together. It is important to determine the factors that make cross-mark...

In recent years, the body of literature on frequentist model averaging in econometrics has grown significantly. Most of this work focuses on models with different mean structures but leaves out the...

This article presents a non-expected utility decision model which is nonlinear in the winning probabilities. The model not only explicitly expresses bidders’ attitudes to risk, but also addresses t...

Subway delays would affect passengers’ travels and cause panic, having massive impacts on urban transit systems. Analyzing causes and the duration of subway delays would necessarily assist operatio...

It is normal for enterprises to engage in remanufacturing nowadays. Nevertheless, the concern of enterprises and researchers is whether remanufacturers should compete for leadership in supply chain...

In this paper we propose an estimation procedure which uses joint data on the underlying asset and option prices to extract market prices of return and volatility risks in the context of the G.A.R.C.H. diffusion model. The procedure is flexible and simple to implement. Firstly, a quasi-closed form pricing formula for European options in the G.A.R.C.H. diffusion model is derived. This result greatly eases the computational burden for computing option prices, and well suited for our model estimation. Then, based upon the joint data, we develop an efficient importance sampling-based maximum likelihood (E.I.S.- M.L.) estimation method for the objective and risk-neutral parameters of the G.A.R.C.H. diffusion model and a particle filter algorithm for latent state variable. Hence, this allows us to infer the market prices of risks that link the objective measure and the risk-neutral measure. Finally, we illustrate our approach using actual data on the Hang Seng Index (H.S.I.) and index warrant prices. The results show that both the return and volatility risks are priced by the market. Moreover, an option pricing study demonstrates that the market price of the volatility risk plays an important role in fitting option prices.

The anti-bullwhip effect, coined by Li et al. in 2005 based on the findings in a simulation study, is the contrary effect of the well-known bullwhip effect. Although there is ample empirical evidence that suggests both effects exist, current literature has not yet provided an integrated framework to address how the two effects are related with each other. By extending the classic work of Lee, Padmanabhan, and Whang of 1997 to a multi-stage supply chain, we derive closed-form formula to analytically describe how the two effects originate initially and then evolve over time and space in the supply chain. Our results show both the bullwhip effect and the anti-bullwhip effect can occur when facing different end-customer demands. However, the magnitude of these effects gradually decreases when moving upstream. We also show the impact of long lead-time on increasing the magnitude of information transformation at the next stage and simultaneously decreasing the magnitude at higher stages. These analytical result...

Supply chain disruption causes tremendous loss to supply chains and global businesses. Organizational structure and operational features of supply chain networks, therefore, constitute a major portion of research for coping with supply chain disruption risk. This article first discusses the theoretical foundation, analyses the strength theory of strong and weak ties and the collaborative theory of strong and weak ties. Also, research methods are explicated; the scale-free networks and the theory of strong ties are integrated; the features of supply chain networks are considered from single statistical parameters and comprehensive analyses. Next, we provide numeric simulation of the properties of supply chain networks, verifying the accuracy of parameter analyses of single statistics and comprehensive analyses. Ultimately, when coping with supply chain disruption risk, each node enterprise of supply chain network is supposed to deploy the characteristics of scale-free networks to systematically man...

This paper proposes two types of dummy variables for an interval regression model to assess the impact of economic shocks/crises on an interval time series (ITS), e.g. daily intervals of energy prices. We present different economic interpretations of the two types of dummy variables for an interval regression model. Particularly, we discuss how they measure the direction and magnitudes of the change of an ITS caused by an economic crisis, and develop the corresponding hypothesis tests. A main advantage of the proposed ITS modelling approach over traditional point-based methods is that it can assess the change in both the trend and volatility of an asset price process simultaneously. This is due to the informational gain of an ITS sample over a point-valued sample, e.g. closing prices, since an interval observation contains both the trend and variation information of a price process in a given period. Using the proposed interval framework, we focus on the impact of the subprime mortgage crisis in the commo...

This article formulates a gaming model of the closed-loop supply chain with manufacturers (as the leader), sellers and consumers where consumers may or may not be willing to pay remunerative price for remanufactured products vis-a-vis new products. In the model, manufacturers produce new as well as remanufactured products, whereas sellers distribute them. In stable circumstances, this article presents the functional formula of the optimal manufacturing pricing decisions. The results show that when the cost of new products is significantly lower than that of remanufactured ones, manufacturers choose to produce new products only. When the difference between cost of new and remanufactured products is moderate, manufacturers tend to produce both new and remanufactured products, and in some regions, production of new and remanufactured products is proportional to each other. When the difference between cost of new and remanufactured products is enormous, their production and sale tend to stop. Also, th...

With the rapid growth of seaborne commodity trades, port development and management has become a challenging issue to the government, enterprise and academia. To alleviate pressures on spatial demand and the environment, sustainable development and scientific management of a port is of crucial importance for its investment, construction and operation. In this article, a research path based on throughput estimation is proposed. The container port of Tianjin could expect to face immense, increasing pressure in the future several years. To meet future increasing capacity requirement, constructing new waterway and berths in a bigger contiguous area or new locations becomes a crucial strategy. Moreover, the strategy of accommodating peak seasonal traffic means existing container terminals have to attain higher output by redesigning their high-precision schedule, reconfiguring terminal topology, improving worker efficiency and employing more modern container-handling facilities.

Shenzhen Port (SZP), once a negligible local port, has risen dramatically to a world-leading container port and an “equal” player with Hong Kong Port (HKP). Will this market share reallocation continue, or will equilibrium be eventually realized for HKP to prosper continuously? We examine the relationship between these two ports to answer this question. We propose a new transformation method to describe the growth of container cargo transport demand, define the quantitative measures of the competition relationship and port competitiveness, and present a rigorous analytical framework with econometric tests and models to understand the true relationship between HKP and SZP. Direct empirical tests suggest that SZP complements HKP; however, the two ports exhibit strong competition when the effect of demand growth is excluded. Considering transshipment separately, we find that the impact of SZP on HKP is negative in transshipment but complementary in direct shipment. We may conclude that HKP does not affect SZ...

The air transport industry crucially depends on traffic forecasting for supporting management decisions. In this study, a singular spectrum analysis (SSA)-based ensemble forecasting modeling approach is proposed. The original air passenger time series is first decomposed into three components: trend, seasonal oscillations, and irregular component. The trend is predicted by generalized regression neural network (GRNN), whereas seasonal oscillations are predicted by radial basis function networks (RNFNs). The empirical results of Hong Kong (HK) air passenger data show a significant improvement of the proposed ensemble method in comparison to other results of competing models.

A new coating stationary phase was prepared and the thermodynamics of the interaction between surfactants and hydrophobically associating water-soluble polymers (HAWP) were investigated according to their chromatographic parameters on the stationary phase. The results indicated that the strength of interaction between single chain sulfonates and HAWP increased as the degrees of mineralization increased and decreased as the substituent carbon number increased, however, the opposite occurred for betaines. The strength of interaction between double chain sulfonates and HAWP increased as the degrees of mineralization increased, and decreased at first and increased later as the double substituent carbon number increased. Besides, the mutual forces between different surfactants with HAWP have also been compared.

An aged emulsion from polymer flooding was dewatered using demulsification and centrifugal separation, and factors of influence on electrical dehydration were investigated. The lowest moisture (0.12%) was achieved at 16000 rpm separated separation. In recycled oil, there were significantly decreases in content of nitrogen, impurities, and iron. The results of simulative electrical dehydration showed that a small amount of separated wastewater (10%) could increase current continually. However, the recycled oil can achieve a satisfactory result of dehydration even mixed with 30% wastewater. It indicated that polymer, impurities, resins, and asphaltene contributed to the electric field collapse of the electric dehydrator.

This paper presents an integrated forecasting model based on the TEI@I methodology for forecasting demand for port logistics services – specifically, port container throughput. The model analyzes port logistics time series data and other information in several steps. In the first step, several econometric models are built to forecast the linear segment of port logistics time series. In the second step, a radial basis function neural network is developed to predict the nonlinear segment of the time series. In the third step, the event-study method and expert system techniques are applied to evaluate the effects of economic and other events that may impact demand for port logistics. In the final step, synthetic forecasting results are obtained, based on the integration of predictions from the above three steps. For an illustration, Hong Kong port's container throughput series is used as a case study. The empirical results show the effectiveness of the TEI@I integrated model for port logistics forecasting.

We develop a production-inventory model for deteriorating items with demand disruption. This differs from the conventional inventory model which is affected only by either deterioration or disruption. In real-life production-inventory systems, deterioration of products and demand disruption are inevitable. The objective of this paper is to address these issues and to be able to derive the optimal production run time and replenishment policy for spot market purchases. We divide the problem into different scenarios according to disruption's time and magnitude. In each scenario the optimal production and inventory plans are provided so that the manufacturer can satisfy the new demand and decrease the loss. Then a numerical example is used to illustrate the model.

Data communication service has an important influence on e-commerce. The key challenge for the users is, ultimately, to select a suitable provider. However, in this article, we do not focus on this aspect but the viewpoint and decision-making of providers for order allocation and pricing policy when orders exceed service capacity. It is a multiple criteria decision-making problem such as profit and cancellation ratio. Meanwhile, we know realistic situations in which much of the input information is uncertain. Thus, it becomes very complex in a real-life environment. In this situation, fuzzy sets theory is the best tool for solving this problem. Our fuzzy model is formulated in such a way as to simultaneously consider the imprecision of information, price sensitive demand, stochastic variables, cancellation fee and the general membership function. For solving the problem, a new fuzzy programming is developed. Finally, a numerical example is presented to illustrate the proposed method. The results show that...

Bid criteria are of prime importance to bidders because they are the basis for the bidders to select bid price or bid mark-up. This article presents the alternative expressions of the bid criteria of the conditional negative and positive profit ratios proposed by Seydel and Olson (1990) and Lai et al. (2002), respectively, and interprets them in the traditional demand and supply theory. It is found that there is a ‘frontier’ bid mark-up if the bidders adopt the conditional profit ratio as their sole bid criterion.

We investigate a robust version of the portfolio selection problem under a risk measure based on the lower-partial moment (LPM), where uncertainty exists in the underlying distribution. We demonstrate that the problem formulations for robust portfolio selection based on the worst-case LPMs of degree 0, 1 and 2 under various structures of uncertainty can be cast as mathematically tractable optimization problems, such as linear programs, second-order cone programs or semidefinite programs. We perform extensive numerical studies using real market data to reveal important properties of several aspects of robust portfolio selection. We can conclude from our results that robustness does not necessarily imply a conservative policy and is indeed indispensable and valuable in portfolio selection.

Cuddington and World Bank-method are modified with trade credits and trade misinvoicing to estimate the short-term and total capital flight (CF) from China. Trade Misinvoicing are adjusted with the transit trade through Hong Kong. It is shown that the short-term is the main component of the CFs from China. Export under-invoicing is the main channel of CFs since 1994, and illegal capital inflow and CF exist simultaneously in China.

The traditional portfolio theory first proposed by Markowitz only provides a solution to capital allocation to a pre-determined set of assets, regardless of asset quality. To remedy this gap, a mul...

A production system is designed with three elements: works, connections and pathways (WCP), which cover how people work, how people connect and how the production line is constructed, from the point of view of a flow unit. The design principle of highly specifying WCP leads to two operations pillars that support the Toyota production system (TPS): just-in-time (JIT) and autonomation. Some stochastic models are proposed to verify the logic of highly specifying work for JIT. The stochastic models show that works are highly specified to reduce the variability whereas highly specifying connections and pathways without resource pooling expose variability in works as low inventory exposes the hidden problems in a factory. To achieve JIT, highly specifying works in each workstation is fundamental; the key solution is to reduce the variability of works. The information entropy theory is used to verify the logic of highly specifying WCP for autonomation. Highly specifying WCP can reduce the information needed by w...

Collaborative credit granting is a key link in the operation of Agile Virtual Enterprise (AVE) chain and its supply chain. This paper first analyzes the measurement model of modern credit risk, and then it pro- poses the selection model of collaborative credit-granting guaranty techniques grounded on capital property pricing, and some important conclusions are further reached on the basis of the empirical studies. Mean- while, n-tier expansion is constructed for the collaborative credit-granting monitoring mechanism grounded on AVE. Under this mechanism, the credit risk in the AVE enterprises can be optimized; and the AVE chain matches the working mechanisms in their capacities of real-time resource sharing, n-tier resource alloca- tion, mission assignment, control and supervision. In the end, the distance management and risk blockage could be accomplished on the supply chains in all the AVE enterprises by forming a strong self-organized and self-control working chain, and the research orientation is indicated by integrating this mechanism with AVE-based Collaborative Planning, Forecasting and Replenishment (CPFR) working system.

This paper addresses a topic of supply chain management from a new perspective: incorporating risk aversion in a supply contract model. A pay to delay capacity reservation contract is analyzed by using the concept of conditional value-at-risk (Cvar). First, we construct the manufacturer’s optimal ordering problem by using the dynamic programming approach. Then, we derive the manufacturer’s optimal ordering strategy and compare our results with those obtained by using expectation performance and mean-variance tradeoff. Finally, numerical results are shown to reveal the impact of risk aversion on the manufacturer’s optimal decisions. The analysis presented in this paper reveals advantages of using the Cvar approach over the mean-variance approach.

With the announcement on 21 July 2005 that the RMB exchange rate regime would be reformed, great attention has been paid to the impact of the RMB's appreciation on China's trade. Since China is in transition from a pegged to a managed floating regime, no existing appropriate model and method can be utilized to investigate this question directly. In this paper, a scenario analysis technique is used to study this issue, coupled with the introduction of the substituted variables: Japanese yen and Euro exchange rate. Our results show that RMB appreciation would not bring severe effects on China's trade in 2005; however, a possible sustained reduction of export growth in 2006 should be given more attention. It is also necessary and urgent to press forward with the reform of RMB exchange rate regime, and put in place the related supporting policies to avoid sudden fluctuations such as the Japanese situation after the “Plaza Accord”.

We introduce the concept of an explicitly B-preinvex fuzzy mapping. Some properties of explicitly B-preinvex fuzzy mappings are also established. Further, various relationships between explicit B-preinvex fuzzy mappings and B-preinvex fuzzy mappings are established.

A stochastic linear goal programming model for multistage portfolio management is proposed. The model takes into account both the investment goal and risk control at each stage. A scenario generation method is proposed that acts as the basis of the portfolio management model. In particular, by matching the moments and fitting the descriptive features of the asset returns, a linear programming model is used to generate the single-stage scenarios. Scenarios for multistage portfolio management are generated by incorporating this single-stage method with the time-series model for the asset returns. Meanwhile, no arbitrage opportunity exists in the proposed method. A real case is solved via the goal programming model and the scenario generation approach which demonstrates the effectiveness of the model. We also comment on some practical issues of the approach.

In choosing a bidding strategy, the original multivariate approach cannot handle a more general and usual bidding situation when the mean value of the bid price for the strategic bidder is not zero. This problem is solved by extending the original approach, assuming that the cost estimate is normally distributed with a non‐zero mean value. The new obtained formula for the probability of winning and the expected profit for the generalized approach are proved to be not influenced by the contract datum parameters and are suitable for determining the optimal mark‐up strategy for a future construction contract. A supplementary model is proposed and combined with the original model to determine relevant parameters in the bid distribution and to justify the previously originally obtained estimation formula. Finally, the real data in the original approach is used to demonstrate the new multivariate analysis approach.

In this paper, we introduce the concepts of a strictly preinvex fuzzy mapping, a semistrictly preinvex fuzzy mapping, a strictly prequasi-invex fuzzy mapping and a semistrictly prequasi-invex fuzzy mapping. Some properties of these mappings and relations among them are studied. A few interesting theorems are proved, including that: (1) a strictly prequasi-invex fuzzy mapping has at most one global minimum point; (2) the solution set is invex if the fuzzy mapping is prequasi-invex and (3) prequasi-invex fuzzy mappings satisfy most of the basic properties of the preinvex fuzzy mappings.

The effects of Japanese yen's depreciation on Chinese exports in 2002 (only considering the exports of the Mainland of China) are analysed. An AR(2) valuation function for the Chinese exports is constructed. The results on sensitivity tests show that the depreciation of Japanese yen would not bring severe effects on the Chinese exports in 2002, though the increasing trend of Chinese exports would become slower.

A study of the vehicle transportation system for a manufacturer is presented. An algorithm based on a dynamic programming model is developed so as to find the optimal transportation arrangements referring to the composition of the vehicles as well as the routing of these vehicles. The algorithm is run under the current condition as well as under a number of different scenarios. It is shown the algorithm can solve the problem with reduced computational complexity. The findings and suggestions resulting from the study can help the department manager in reviewing current operations arrangement and determining future operations arrangements.

This paper is concerned with when to implement preventive maintenance (PM) and replacement for a repairable ‘single-unit’ system in use. Under the main assumption that a ‘single-unit’ system gradually deteriorates with time, a sequential method is proposed to determine an optimal PM and replacement strategy for the system based on minimising expected loss rate. According to this method, PM epochs are determined one after the other, and consequently we can make use of all previous information on the operation process of the system. Also the replacement epoch depends on the effective age of the system. A numerical example shows that the sequential method can be used to solve the PM and replacement problem of a ‘single-unit’ system efficiently. Some properties of the loss functions W(Ln,bn) and Wr(N) with respect to PM and replacement respectively are discussed in the appendix.

We study the optimal portfolio selection problem with transaction costs. In general, the efficient frontier can be determined by solving a parametric non-quadratic programming problem. In a general setting, the transaction cost is a V-shaped function of difference between the existing and the new portfolio. We show how to transform this problem into a quadratic programming model. Hence a linear programming algorithm is applicable by establishing a linear approximation on the utility function of return and variance.

In this paper. we are concerned with approximate solutions to a multiobjective and nonconvex programming problem. A new concept of e-proper efficiency is :ntroduced. A few of necessary and/or sufficient conditions for an e-efficient solution (:.esp.. an e-properly efficient. an e-weak efficient solution) are derived via scalarization and an alternative theorem. The resultsin this paper generalize and refine some known results in multiobjective optimization.

In this paper, we propose a two-level hierarchical optimization model for an institution (say an enterprise) to allocate resources among its departments. The top decision maker (the board or the general manager) of the institution makes a decision on how to allocate resources to n departments. In the lower level, the head (the manager) of each department is requested to estimate the maximum benefit his department will gain if it consumes a certain amount of resources, possibly obtained from the top decision-maker. In the top level, the top decision-maker allocates resources to n departments by solving an optimization problem in which the information of the expected maximum benefits of the n departments are involved. An incentive strategy is also suggested to support the top decision-maker in inducing the lower-level decision makers of the departments to provide him information truthfully. Under a very mild assumption, we prove that an allocation decision made by the top decision-maker with thc method pres...

In this paper we study second-order optimality conditions for the multi-objective programming problems with both inequality constraints and equality constraints. Two weak second-order constraint qualifications are introduced, and based on them we derive several second-order necessary conditions for a local weakly efficient solution. Two second-order sufficient conditions are also presented.