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This paper proposes a stochastic production planning model for an international enclosure manufacturing company with seasonal demand and market growth uncertainty. The company purchases material and subassembly from overseas and long lead times have been observed. To prevent excess inventory and stockout, the company is required to forecast its demand and project its purchasing decisions and production load to its key suppliers in an effort to reduce risks for both parties. To assist purchasing and production decisions, a two-stage stochastic production planning model that explicitly includes uncertainty is developed with the goal of minimising the total production, inventory, and overtime costs under all scenarios. The model is solved using real data from the company and results have demonstrated the effectiveness of the model compared with various deterministic models. Parametric analyses are performed to derive managerial insights related to issues such as overtime usage, inventory holding costs and the proper selection of scenarios under pessimist, neutral, and optimist outlooks. The model has been implemented and an annual saving of more than $400,000 in inventory cost has been achieved. [ABSTRACT FROM AUTHOR]

The toy industry faces relentless change and an unpredictable buying public, which creates immense challenges in anticipating best sellers and predicting volume. Like the high-technology industry, toys also suffer from many supply chain ailments including short product life, rapid product turnover, and seasonal demand. Coupled with long supply lines and ongoing political and economic turmoil in Asia, toy makers face an unusually complex set of risks. Managers in many businesses can learn valuable lessons in managing uncertainty from toy makers. This article describes supply chain lessons focused on reducing risk by actively managing both demand and supply variability. These lessons include product variety strategies based on product extensions; rolling mix strategies; leveraged licensing agreements; coordinated outsourcing strategies; and hedging against political and currency risk by producing in many different countries. [ABSTRACT FROM AUTHOR]

Highlights • Unique aspects of three different CSP collector designs are identified. • Central receiver technology is most sensitive to the solar field optical errors. • Both latitude and annual solar irradiation are critical in the plant site selection. Abstract The optical performance of a concentrating solar power (CSP) collector is critical to the overall efficiency of the system. This study presents a detailed optical comparison between three representative CSP collector designs including linear Fresnel, parabolic trough, and central-receiver technologies. Optical models are implemented in SolTrace, which is ray-tracing software developed at the National Renewable Energy Laboratory. The ray-tracing algorithm is used to calculate a collector's design-point performance as well as its incidence-angle modifiers to evaluate the collector performance at any sun position during a typical meteorological year. The efficiency over a one-year period is then analyzed based on ray-tracing results. Using China Lake (California) as an example, the annual optical efficiency is 60% for the selected parabolic trough collector, 52% for the selected central-receiver technology, and 40% for the selected linear Fresnel collector. The parabolic trough has the highest optical performance among all. The selected central-receiver technology provides the most consistent seasonal production profile over the course of the year due to its two-axis-tracking ability but would suffer most from the increasing solar collector optical error. It is also shown that a dramatic cost reduction is required for the selected linear Fresnel technology to be competitive in the future energy market. Sensitivity of three CSP technologies to the deployment locations and the overall optical-error magnitude is also examined through annual performance analysis. The results will provide insights into a better understanding on inherent technical aspects of different CSP technologies. [ABSTRACT FROM AUTHOR]

Virtually every product is seasonal; seasonality often dictates business strategy. In this article, the authors (1) show how to add known seasonal patterns to any dynamic model parsimoniously and without changing the fundamental model assumptions, (2) illustrate how their method provides strategic implications for timing new product introductions, and (3) provide an empirical application. The authors transform time so that, during high seasons, time is moving faster than normal time. Traditional methods only adjust sales, independent of the underlying sales model. The authors' method also changes the product's growth along its life cycle and suggests that timing introduction decisions are dependent on the shape of the product's life cycle. The authors' empirical work compares their theoretical results with empirical observations. With data for all major films released between July 1993 and 1995 (673 films), the authors estimate the seasonal pattern for the motion picture industry and compare their theory with studio behavior. [ABSTRACT FROM AUTHOR]

What are the real bases of the bargaining power problem in agricultural markets? Is antitrust action an effective remedy? Can cooperative marketing improve farmers, bargaining positions? What is the impact of federal price-support programs on bargaining, power in farm-product markets? This article gives you the answers to these questions. [ABSTRACT FROM AUTHOR]

The article discusses seasonal psychology and the differences in human behavior during each season. The psychoseasonal trend is described for its marking Americans' perceptions of seasonal change. Word association tests are noted. Winter reportedly has the shortest seasonal association, while spring has the longest. People who are exclusively oriented towards one season are described. Deseasonalizing influences are explained. The article describes differing cultural, economic, psychological and social behavior depending on the season or time of year.

Leasing is one of the several marketing tools at the disposal of the firms which manufacture or distribute equipment. Like all other tools, it has its merits and limitations, varying in importance according to the industry or trade group under consideration. Confronted with a period of rapid change and a growing measure of uncertainty, marketing executives should further explore the applicability of leasing to the distribution of their products. It might prove to be the indicated strategy for turning a rapid decline in sales volume into a more stable income from lease payments, as well as a means of supplying equipment users with cost-saving machines at a time when increased emphasis is commonly placed on economy. In order to be viewed as an acceptable marketing plan, however, leasing necessarily must represent more than a stopgap device for stemming the tide of declining sales during a depression period. The prospective lessor must ascertain that worthwhile features are present for the buyer as well as the seller, features which justify the leasing plan under all degrees of business prosperity. The prospective lessee likewise must cultivate an open-minded and fact-finding approach to the plan. There is a danger that leasing might appear as an easy solution to a troublesome service and modernization problem and an escape from the handicap of inadequate capital resources. The inevitable added costs, payments for services, and risk-bearing which are a part of leasing, must be weighed against the cost of using self-owned equipment. An astute and enlightened approach to such decisions may be the determining factor in the ever-present search for lower production and marketing costs. [ABSTRACT FROM AUTHOR]

We compare two strategies of ordering and pricing postponement for a seasonal product. In the single‐opportunity strategy, the retailer orders all base‐stock prior to the beginning of the season and sets the price when the season begins and demand information becomes available. In the two‐opportunity strategy, the retailer orders only some of her stock before the season, and places an additional order after the season starts; the second‐order quantity and the prices for each quantity of base‐stock are determined according to currently available demand information. The latter strategy can accommodate unexpected demand changes that occur late in the selling season. We provide sufficient conditions in which the two‐opportunity strategy is preferable to the single‐opportunity strategy. Each problem is analyzed using a multistage programming approach, and optimal prices as well as optimality conditions for the different base‐stock levels are obtained. In contrast to previous studies, our model addresses the effect of the timing of the arrival of the second order and accounts for holding costs over time as well as a reputation penalty associated with lost sales. Moreover, it does not ignore fixed costs associated with order placement and processing of demand information. A numerical example and sensitivity analysis of the key parameters show that the ratio between the optimal expected profits obtained under the single‐opportunity strategy and under the two‐opportunity strategy is lower for higher values of the holding costs or reputation penalty. Moreover, the ratio is higher for later splitting points as well as for higher fixed costs. [ABSTRACT FROM AUTHOR]

Kimchi is prepared by fermenting salted vegetables with various ingredients and lactic acid bacteria, which are essential for the process. The aim of this study was to expiscate phylogenetic associations with the season and salinity of manufactured kimchi with respect to bacterial-community composition. We analyzed 66 Chinese cabbage kimchi samples obtained in the spring, autumn, or winter from commercial sources in six Korean provinces (Gangwon, Gyeonggi, Chungcheong, Gyeongsang, Jeolla, and Jeju) by Illumina MiSeq sequencing. The pH and salinity of the kimchi samples ranged from 5.02 to 6.13 and 1.40%–3.30%, respectively, and the salinity differed significantly by season and influenced bacterial-diversity indexes. Variations in operational taxonomic units and the Shannon index correlated significantly with salinity and seasonality. Moreover, microbial-community differences were strongly reflected in the seasonality of kimchi samples in non-metric multidimensional scaling plots and by analysis of similarity. Additionally, the distribution patterns of Leuconostoc , Lactobacillus , and Weissella spp. were well predicted by seasonality, demonstrating the importance of comprehensive correlations in bacterial community on variable environmental factors. Understanding key processes that control microbial distributions during kimchi fermentation offer insight into the biological variations of this food and the relationship between various kimchi properties and its microbiota. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to examine merchandise performance-based financial productivity of offshore vs reshore sourcing scenarios for fashion/seasonal products with higher demand uncertainty, using computer simulation software.Design/methodology/approach Using Sourcing SimulatorTM, the researchers generated a data set of 530 simulations concerning merchandising performance measures for offshore and reshore sourcing scenarios. Analysis of covariance was conducted for data analysis.Findings Results show financial productivity differs, depending on a sourcing decision between offshore and reshore sourcing scenarios as well as on the levels of volume error and assortment error. The reshore sourcing scenario through “Made-in-USA” domestic production strategy can have a better profitability, including gross margin return on inventory with service level, in cases of under-volume error and over-assortment error, than the offshore sourcing scenario.Research limitations/implications Findings from this study are based on simulation data, which may have a gap between simulations and reality concerning the competitive advantages of “Made-in-USA” domestic production strategy. “Made-in-USA” domestic production strategy can be more agile and responsive to the uncertainty of markets and customer demands when the supply chain systems are well-integrated and fully implemented.Originality/value Results from this study contribute to fill the literature gap about differences of financial productivity between offshore and reshore sourcing scenarios for apparel manufacturers and retailers. This study also offers an insight of which decision response may be better to uncertain customer demands, while satisfying financial productivity. [ABSTRACT FROM AUTHOR]

On-site odor measurements and mathematical modeling are useful for identifying the odor impact at the source and receptors located in areas adjacent to wastewater treatment plants (WWTPs). Impact of open area sources can be significant and may influence air quality both at the WWTP area and downwind in the surrounding areas. In this work, results of the odor measurements carried out in the spring and summer season for sources within three different mechanical-biological WWTPs in Poland are presented. The odor impact assessment was completed using a Polish reference model. The odor emission scenarios considering the contribution of major odor sources within WWTPs and the seasonal variation were determined. Obtained results showed significant differences between spring and summer seasons. The highest and the lowest measured odor concentrations at the WWTP property line were 75 ouE/m³ (July) and 6.4 ouE/m³ (March), respectively. [ABSTRACT FROM AUTHOR]

The concept of food sovereignty is becoming an element of everyday parlance in development politics and food justice advocacy. Yet to successfully achieve food sovereignty, the demands within this movement have to be compatible with the way people are pursuing consumer sovereignty and vice versa. The aim of this article is to examine the different sets of demands that the two ideals of sovereignty bring about, analyze in how far these different demands can stand in constructive relations with each other, and explain why consumers have to adjust their food choices to seasonal production variability to promote food sovereignty and so secure future autonomy. [ABSTRACT FROM AUTHOR]

Many seasonal products are transported via ocean carriers from origin to destination markets. The shipments arriving earlier in the market may sell at higher prices, but faster shipping services can be costly. In this paper, we study a newsvendor-type shipper who transports and sells seasonal products to an overseas market, where the selling price declines over time. A set of vessels with different schedules and freight rates are available to choose from. Our analysis demonstrates that a portfolio of vessels has two distinct effects on mitigating uncertainties in both demand and vessels' arrival schedules, while these two portfolio effects have been previously understood as separate issues in the literature. To find the optimal portfolio in our problem, we first show that when vessels arrive in a deterministic sequence, the optimal portfolio can either be derived in closed form (in the single-demand setting), or computed efficiently with a variation of the shortest-path algorithm (in the multi-demand setting). Then, based on these results, we propose an approximation procedure to address the general problem with an uncertain arrival sequence. In each iteration of the procedure, we only need to minimize a cost function approximated by a deterministic arrival schedule, and the portfolio generated can converge to the optimal one under mild conditions. Finally, we present a real-world case study to demonstrate several practical implications of managing a carrier portfolio. The online appendix is available at . [ABSTRACT FROM AUTHOR]

With a random price-dependent demand, this paper investigates the capital-constrained retailer's integrated purchase timing, quantity and financing decisions towards seasonal products. Results show that at both purchase moments (i.e. early-purchasing at the beginning of lead time and late-purchasing at the beginning of selling season), there always exists a critical value, and when the retailer's internal capital level is less than the critical value, it will borrow from the bank to purchase a larger quantity; otherwise, it will not borrow and just use up its internal capital for purchasing. The capital-constrained retailer can get an “information bonus” from late-purchasing only when its internal capital level is relatively low, so it needs a trade-off between the “conditional information bonus” and the “inevitable cost loss” brought by late-purchasing and then makes an optimal purchase timing decision. A specific multi-parameter-based method is highlighted to solve the timing decision problem. Based on above findings, this paper designs a simple intelligent purchasing decision support system for small retailers. The proposed system integrates two main functions of purchasing and financing to help small retailers, especially those with limited working capital, make more scientific and intelligent purchasing decisions. [ABSTRACT FROM AUTHOR]

To satisfy its need for seasonal low-skilled labourers, Canada is hiring temporary foreign workers (TFWs). As part of a study on the management issues related to the hiring of TFWs, employers and informants from related NGOs and governmental agencies were interviewed about their motivations to use TFWs. The primary motivation, unlike that which would be expected, is not cost savings. The interest in hiring TFWs would appear to be based on cost-utility considerations, including the benefit of an available, efficient, loyal workforce during the whole season and the flexibility for employers to reduce risk and uncertainties related to the availability of labour. Employers thus give preference to TFWs rather than local workers, because they meet the entirety of their expectations of workforce flexibility, be it numerically or in relation to scheduling, remuneration or skills. [ABSTRACT FROM AUTHOR]

In literature, many inventory studies have been developed by assuming deterioration of items as either a variable or constant. But in real life situation, deterioration of goods can be reduced by adding some extra effective capital investment in preservation technology. In this paper, a deteriorating inventory model with ramp-type demand under stock-dependent consumption rate by assuming preservation technology cost as a decision variable is formulated. Shortages are allowed and the unsatisfied demand is partially backlogged at a negative exponential rate with the waiting time. The objective of this study is to obtain the optimal replenishment and preservation technology investment strategies so that the total profit per unit time is maximum. Further, the necessary and sufficient conditions are considered to prove the existence and uniqueness of the optimal solution. Some numerical examples along with graphical representations are provided to illustrate the proposed model. Sensitivity analysis of the optimal solution with respect to major parameters of the system has been carried out and the implications are discussed. [ABSTRACT FROM AUTHOR]

A high share of Brazilian power generation comes from hydropower sources and a further expansion of power generation is necessary due to high growth rates in electricity demand. As an alternative to the expansion of hydropower which shows high seasonal and annual variability with risks of load shedding due to droughts, windpower production may be increased. We assess the variability of potential windpower plants in the four most important windpower producing states Ceará (CE), Rio Grande do Norte (RN), Bahia (BA) and Rio Grande do Sul (RS) in comparison to adding new hydropower capacities in the North region. We assess seasonality and long-term deviations from seasonal production patterns. For that purpose, time series of windpower production from wind speeds derived from measurements and two global climate reanalysis models (NCAR and ECMWF) are generated and validated. Our results show that seasonal variability of windpower generation in the North-Eastern states is anticyclical to hydrological seasonality in the South-East, North-East, and North region of Brazil. Deviations of simulated windpower production from the monthly means are less correlated with current hydropower production than deviations of potential new hydropower projects. Adding windpower instead of hydropower to the system decreases significantly the risk of long periods of very low resource availability. The states Bahia and Rio Grande do Sul perform best with respect to that measure. Our validation procedure shows that ECMWF data may be the best source of long-term wind time series as it better reproduces ground measurements than NCAR. [ABSTRACT FROM AUTHOR]

Each autumn, the village of Kalloni in Greek Macedonia is woken from its usual seasonal slumber by groups of mushroom hunters. Since the former inhabitants migrated to surrounding towns during the 1940s, Kalloni has gradually become deserted outside of the summer months. The mushroom-picking season ignites dormant social networks of embodied knowledge and history. Mushrooms facilitate a polytemporal link to historical and sensory experience and are central to the cultural repertoire of negotiating social change. History is relived through mushroom-picking and embodied knowledge transmitted. Successive generations maintain a highly ritualized practice infused with notions of historical constructivism, polytemporality diverse forms of exchange and kinship rivalry. Artifacts, food, information, memory and narratives are exchanged during the mushroom season. The veil of secrecy that surrounds mushroom-picking is only ever partially de-shrouded as misinformation, deceit and competition are widespread. The practice has become culturally proximate as an activity that links dispersed actors to their ancestral village. Mushroom-picking enlivens otherwise abandoned social spaces and activates networks of relations and knowledge. Thus, mushrooms not only help produce a dynamic social arena of discernment, but also facilitate historical consciousness. [ABSTRACT FROM AUTHOR]

Background:Tropical montane cloud forests (TMCF) are unique ecosystems with high biodiversity and large carbon reservoirs. To date there have been limited descriptions of the carbon cycle of TMCF. Aims:We present results on the production, allocation and cycling of carbon for two mid-elevation (1500–1750 m) tropical montane cloud forest plots in San Pedro, Kosñipata Valley, Peru. Methods:We repeatedly recorded the components of net primary productivity (NPP) using biometric measurements, and autotrophic (Ra) and heterotrophic (Rh) respiration, using gas exchange measurements. From these we estimated gross primary productivity (GPP) and carbon use efficiency (CUE) at the plot level. Results:The plot at 1500 m was found very productive, with our results comparable with the most productive lowland Amazonian forests. The plot at 1750 m had significantly lower productivity, possibly because of greater cloud immersion. Both plots had similar patterns ofNPPallocation, a substantial seasonality inNPPcomponents and little seasonality inRa. Conclusions:These two plots lie within the ecotone between lower and upper montane forests, near the level of the cloud base. Climate change is likely to increase elevation of the cloud base, resulting in shifts in forest functioning. Longer-term surveillance of the carbon cycle at these sites would yield valuable insights into the response of TMCFs to a shifting cloud base. [ABSTRACT FROM PUBLISHER]

The article discusses the apparel segment of the market for seasonal products in Poland. Its purpose is to characterise the segment and to determine how competitive domesticallyowned manufacturers are. To this end, the authors use GUS (Central Statistical Office) data, their own findings, as well as data derived from the Polska 2000 ranking. The first part of the article presents secondary data and formulas that were used to compute values illustrating the size of the market segment selected and the changing shares of domestically- made products. In the second part, the scope of the research is extended due to the lack of other secondary data, except for aggregate (on clothing, footwear, and accessories). The last part of the article presents a ranking of the largest companies operating in the selected segment of the Polish market by the type of ownership (Polish, foreign). As the GUS data used in the analysis were collected in the period of global financial crisis, its impacts can be seen through the research outcomes. [ABSTRACT FROM AUTHOR]

Traditional ordering decisions for seasonal products often focus on minimizing expected cost or maximizing expected profits, which assume decision makers to be risk neutral. In this paper, we incorporate retailer's different risk attitudes by means of spectrum risk measure into the ordering decision model for seasonal products, and discuss the optimal ordering decisions of the retailer under the option contract mechanism. We show that the optimal ordering quantities of cash commodity and option commodity are existent and unique, and then analyze the specific ordering strategy, of the retailer who has different risk preferences through the mean-CVaR risk spectrum function. The effects of the retailer's risk attitude, and the price parameters of option contract on the optimal ordering decisions are also analyzed. Finally, we illustrate our theoretical results by some numerical examples. [ABSTRACT FROM AUTHOR]

In order to adapt the seasonal production of donkey milk to constant market demand, this study was aimed to define the project parameters of a pilot spray dryer for producing soluble milk powder from donkey milk concentrate. The concentrate (23% mean dry matter (wb)) was spray-dried using three different inlet air temperatures (120-150-185 °C). Both cow and goat milk were used as reference in the trials, and ascorbic acid was used as a chemical marker to evaluate thermal damage to the powder. The thermal damage index (IDT) and insolubility index (IINS) were used to assess the quality of the powders produced. Prediction models were developed for each kind of milk to correlate spray-drying operating temperatures to the IINS and IDT. The results of experimental trials were used to determine optimal processing temperatures (both inlet and outlet air temperature) in order to obtain an 'extra-grade' milk powder from donkey milk concentrate (the maximum allowed inlet air temperature that resulted was 173.5 °C). [ABSTRACT FROM AUTHOR]

In this paper, our purpose is to analyze how market power might affect the allocation of production between seasons (summer and winter) in a hydropower system with reservoir constraints and inflow uncertainty. We find that, even without market power, the price in the summer season might be lower than the expected price in the winter season. In some situations, market power can lead to higher sales and a lower price in summer than would be observed in the competitive outcome; in other situations, it can lead to the opposite result. Furthermore, market power can lead to a smaller price difference between summer and winter. [ABSTRACT FROM AUTHOR]

A study by Phoenix utility has provided very promising results to help it design and implement TOU pricing strategies that can dramatically change/improve its system load profile. It has also provided insight and deeper understanding that has led SRP to view these TOU options as a portfolio where it can actually optimize customer participation in TOU pricing programs. [ABSTRACT FROM AUTHOR]

Abstract: This paper considers advance order strategies in a two-echelon supply chain with one supplier and multiple buyers for seasonal products. We study how advance strategies affect the interactions between the supply chain members. In contrast to much of the literature, we specifically consider the supply chain with multiple buyers by introducing a demand function under uncertainty. Furthermore, we present two main different advance order strategies. We assume that exactly one of the multiple buyers has the ability to make an advance order before the selling season (we call this buyer the natural leader). In one strategy, the natural leader can only order products one time. The model shows that, below a threshold level of demand uncertainty, the supplier can benefit from providing adequate pricing incentives to entice the natural leader to order products before demand information is revealed. In another one, the natural leader can order products two times, we find that the supplier always can gain more profit from this advance order strategy. Our results show that the first advance order strategy is easier to control but has more strict constraint on coefficients of variation, while both two advance strategies bring more flexibility to the supply chain. [Copyright &y& Elsevier]

The article provides information on the use of simple mantra for re-examining the demand plan of a business. It states that mantra is described by Indian philosophy as a sound or group of words that are considered capable of creating transformation. The author also emphasizes the use of Level-Trend-Seasonality-Change when asking questions on critical assumptions in any demand plan.

Since the 1930s turkey production in the United Kingdom has been transformed from a small scale, seasonal activity catering exclusively for the Christmas market, to an intensive mass production sector dominated by all year round producers, of which Bernard Matthews is the best known. This revolution in production methods reflects improved methods of disease control, enhanced nutritional understanding, and the development of more productive strains of turkeys with better conformation. These supply side changes have been accompanied by a succession of very successful marketing campaigns to persuade consumers of the merits of eating turkey throughout the year. This article investigates the reasons for the commercialisation of the turkey industry since the 1930s. [ABSTRACT FROM AUTHOR]

This paper considers the sale of a seasonal product in the face of strategic customers. At the beginning of the selling season, the retailer announces both the price p h at which the product will be sold during the selling season and the post-season clearance price p ℓ< p h for unsold items. We analyze two operating regimes: The 'no reservation regime' allows a buyer either to purchase the product at price p h when he arrives or to enter a lottery to purchase at price p ℓ if the product remains unsold. The 'reservation regime' offers each buyer one extra option than the no reservation regime: reserve the product for purchase at the clearance price p ℓ. If the buyer reserves the product under the reservation regime and if it remains unsold at the end of the selling season, then he is obligated to purchase it at price p ℓ. We consider a situation in which heterogeneous customers with probabilistic valuation arrive in accord with a Poisson process. We characterize the rational purchasing behavior wherein each arriving customer is strategic; each customer takes other customers' purchasing behavior into consideration. By considering the Nash equilibrium of this game, we show that strategic customer behavior can render the customer to be worse off and the retailer to be better off under the reservation regime, despite the fact that this regime offers one extra option (reservation) to a customer. Hence, more purchasing options do not necessarily benefit customers. [ABSTRACT FROM AUTHOR]

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Abstract: An inventory model for a deteriorating item (seasonal product) with linearly displayed stock dependent demand is developed in imprecise environment (involving both fuzzy and random parameters) under inflation and time value of money. It is assumed that time horizon, i.e., period of business is random and follows exponential distribution with a known mean. The resultant effect of inflation and time value of money is assumed as fuzzy in nature. The particular case, when resultant effect of inflation and time value is crisp in nature, is also analyzed. A genetic algorithm (GA) is developed with roulette wheel selection, arithmetic crossover, random mutation. For crisp inflation effect, the total expected profit for the planning horizon is maximized using the above GA to derive optimal inventory decision. On the other hand when inflationary effect is fuzzy then the above expected profit is fuzzy in nature too. Since optimization of fuzzy objective is not well defined, the optimistic/pessimistic return of the expected profit is obtained using possibility/necessity measure of fuzzy event. Fuzzy simulation process is proposed to determine this optimistic/pessimistic return. Finally a fuzzy simulation based GA is developed and is used to maximize the above optimistic/pessimistic return to get optimal decision. The models are illustrated with some numerical examples and some sensitivity analyses have been presented. [Copyright &y& Elsevier]

Seasonal products have an effective inventory deadline, a time by which the inventory must be ready to distribute. The deadline creates an incentive to start early with production. However, opportunities to gather information that might change production decisions provide an incentive to defer the start of production. We study the resultant dynamic decision problem with alternatives that commit to one of several courses of action now and an alternative to defer the commitment to gather more information about the possible consequences of each alternative. The deadline increases the effective cost of gathering information because that cost includes the value sacrificed by reducing the time available to produce inventory. We frame our model using the annual influenza vaccine composition decision: deciding between strains of the virus to include, which must happen in the spring to allow time for vaccine production before the fall flu season begins. Our analysis describes the optimal decision strategies for this commit-or-defer decision. Many insights are drawn from this model that could contribute to more informed flu vaccine composition decisions. We comment on the relevance of this commit-or-defer decision model to a firm's production decisions for other seasonal products with an inventory deadline such as fashion goods. [ABSTRACT FROM AUTHOR]

Abstract: Motivated by the common practice that competitive retailers usually transship inventories between each other to increase sales, this article studies the optimal transshipment policies of two retailers selling a same kind of seasonal or fashionable products in a same market. In the problem under investigation, before the selling period begins, both retailers hold a certain quantity of initial inventories that are non-replenishable during the selling process. Once one of the retailers has run out of its inventory, it can rely on the inventory that is transshipped from the other retailer to fulfill its customer. However, as a self-revenue maximizer, the other retailer can reject any transshipment requests. On basis of a discrete-time dynamic programming model, we study the optimal transshipment policies of the two retailers, and characterize the structural properties of their revenue functions. Moreover, we conduct a comparison of the decentralized system with the centralized system where both retailers seek to maximize their joint revenue. Numerical experiments show that though transshipment can increase revenue for both retailers, however, the competition between the retailers can induce a great total revenue loss. [Copyright &y& Elsevier]