High Stocking Levels Research Articles

Carbon stocks and footprints of smallholder cacao systems in Polewali Mandar, West Sulawesi

Cacao (Theobroma cacao) is a commodity that plays an important role in supporting economic and social development. However, cacao production can also be a major contributor to carbon emissions, which has stimulated various efforts toward sustainable cacao farm management. There remains a gap in knowledge regarding the links between carbon stocks and carbon footprints, which can serve as indicators of environment “friendliness.” In this study, we investigated carbon stocks and carbon footprints in two cacao cultivation systems, agroforests and monocultural systems, and the biophysical aspects (biotic and abiotic factors) that might contribute to the variability of carbon levels. System inventories, soil samples, and farmer interviews identified the characteristics and management practices of two cacao production systems. Results show that cacao agroforests accumulated more carbon stocks than cacao monocultures, 134.4 Mg C ha−1 and 104.7 Mg C ha−1, respectively, while cacao monocultural systems had higher carbon footprints than cacao agroforests, 1914.4 kg CO2e ha−1 and 932.1 ± 251.6 kg CO2e ha−1, respectively. Canopy cover, tree density, and soil organic carbon were the biophysical aspects that showed a significantly positive correlation with carbon stock levels, while canopy cover had a significantly negative correlation with carbon footprint levels. These results suggest that cacao agroforests are more climate-friendly management systems due to their ability to maintain high carbon stock levels while producing low carbon footprints.

The current state of Japanese mackerel Scomber japonicus and the peculiarities of its nutrition in feeding areas

During a period of high stock levels chub mackerel migrates to Russian waters for feeding and become available for domestic fisheries. In 2016, the domestic mackerel fishery was organized after a long break. Mackerel catches increased until 2018, followed by a slight decline. Based on the materials of the autumn survey conducted in Russian waters of the Northwest Pacific Ocean in 2020, the size and age composition, biological condition and nutrition of chub mackerel during feeding in the South Kuril zone is given.

E-Inventory Management and Performance of Food and Beverages Manufacturing Firms in Kenya

Manufacturing companies in Kenya have been experiencing problems in the performance of their production and operations management. Stock-outs result from holding too little stock of the offending lines because the forecasts and material requirement planning controls are inadequate. High stock levels arise because too much stock has been purchased through bad forecasting, monitoring or controls. The aim of this research was to investigate the effect of e-inventory management on the performance of food and beverage manufacturing firms in Kenya. The study had specific objectives, which were to determine the influence of material requirement planning and radio frequency identification on the performance of these firms. The research design used was descriptive, and the target population was individuals employed in food and beverage firms in Kenya. A stratified random sampling method was employed due to the heterogeneous nature of the population. Structured research data was collected and analyzed using descriptive and multiple regression analysis.
 The study found that radio frequency identification had the second highest impact on the performance of food and beverage firms in Kenya, with a β value of 0.295 and a P-value of 0.004. Additionally, material requirement planning technology had the greatest influence on the performance of food and beverage firms in Kenya, with a β value of 0.316 and a P-value of 0.006. Based on these results, it can be concluded that food and beverage firms in Kenya should prioritize the use of radio frequency identification technology for better operational efficiency and performance. The study also recommends that management should focus on accurately forecasting inventory demands and providing inventory management training for employees.

Effect of Vitamin E Supplementation on the Growth Performance of Clarias Sp.

The high demand for catfish motivates farmers to increase production by stocking at a high density. The stress response caused by stocking density, which has an effect on fish growth and survival, is one of the challenges associated with catfish farming with high stocking levels. This issue can be resolved by supplementing catfish feed with vitamin E to stimulate growth. This study aims to determine the effect of vitamin E supplementation on catfish growth, feed efficiency, and survival. This study employs the RAL method with five treatments, including feeding catfish seeds with vitamin E levels of 0 mg/kg feed (P1), 50 mg/kg feed (P2), 100 mg/kg feed (P3), 150 mg/kg feed (P4), and 200 mg/kg feed (P5), with each treatment repeated four times. Adding 100 mg of vitamin E per kg of feed resulted in the highest growth rates (1.66 0.05%/day), a feed conversion ratio of 1.2 0.07, and a feed efficiency of 83.46 3.24% when compared to other treatments and was significantly different (p 0.05). The addition of 100 mg of vitamin E to the feed had no discernible effect on survival compared to other treatments.
 Keyword: Vitamin E, supplementation, growth, Clarias sp.

Improving Sales Forecasting by Combining Key Account Managers’ Inputs and Models Such as SARIMA, LSTM, and Facebook Prophet

Sales forecasting is important for a company to plan its production. The quality of its forecasts influences finances and the product availability. The impact of sales forecasts on a company may result on an immobilization of cash flow by causing a high stock level, which is the opposite of out-of-stock impact. The purpose of this study was to find a suitable model for predicting the best company sales forecasts that has a better accuracy or production plan. The proposed method includes an adjustment of the prediction model by including the key account managers’ expertise as qualitative forecasting method. This adjustment was analyzed using different time series forecasting techniques such as exponential smoothing, seasonal autoregressive integrated moving average and Facebook Prophet. These techniques were compared in parallel with neural network approaches such as long-short term memory. Comparisons were made using root mean square error and residual stock to determine whether the forecasts were too optimistic or pessimistic. The proposed model is dynamic. Adjustments of the qualitative inputs could directly influence the proposed values obtained using different quantitative methods.

Experimental and numerical study on the influence of shaped charge liner cavity filing on jet penetration characteristics in steel targets

Penetration characteristic (size and shape of penetration craters made in high hardness ARMSTAL 30PM steel) of shaped charge jets formed after detonations of modified PG-7VM warheads was analyzed in the article. Modifications consisted in removing the frontal part of the grenade (fuse, ballistic cap and conductive cone) and introducing of the liner cavity filling made of polyacetal copolymer POM-C. The filings in the form of solid cones with three different heights (33%, 66% and 100% of H - the height of original PG-7VM liner) were placed inside of the hollow cone shaped charge liner. As opposed to the vast majority of previously published works (in which warhead optimization studies were focused on increasing of the depth of penetration in rolled homogeneous armor steel) the main aim of the presented modifications was to maximize the damage ratio (diameters of craters, inlet and outlet holes) of target perforated by shaped charge jet at the cost of the loss of part of the jet penetration capability. According to the best knowledge of the authors such approach to the use of the old PG-7VM warheads has not been analyzed so far. Taking into consideration high stock levels of PG-7VM warheads, and the fact that they are continuously being replaced by more efficient and more sophisticated high-explosive anti-tank warheads, it seems reasonable to look for alternate applications of the warheads withdrawn from the service. Thanks to the introduction of proposed modifications the warheads could be used by special forces or other assault units as directional mines or statically detonated cutting shaped charges as well as by combat engineers as universal charges used in various types of engineering or sapper works. The research included experimental penetration tests and their numerical reproduction in the LS-Dyna software with the simulation methodology defined and validated in previous works of the authors. Small differences (average error = 10–20%) were identified between the experimental and numerical results (dimensions of craters made in steel targets were compared) what confirmed the reliability of the modelling methodology and enabled its use for further optimization of the shapes of fillings. Within the analyzed variants of warheads modifications maximum diameters of penetration craters were obtained for the filling of the height of h = 2/3H. The diameters of holes in individual steel plates were increased by 164%, 70%, 65% (for the first, second and third plate, respectively) in relation to the variant without filling. The results of the study indicated that with the use of different materials of fillings and their various heights it is possible to control the shape of penetration craters pierced in the steel targets.

Evaluation of the pharmaceutical distribution and warehousing companies through an integrated Fermatean fuzzy entropy-WASPAS approach

PurposePharmaceutical supply chains (PSCs) need a well-operating and faultless logistics system to successfully store and distribute their medicines. Hospitals, health institutes, and pharmacies must maintain extra stock to respond requirements of the patients. Nevertheless, there is an inverse correlation between the level of medicine stock and logistics service level. The high stock level held by health institutions indicates that we have not sufficiently excellent logistics systems presently. As such, selecting appropriate logistics service providers (drug distributors) is crucial and strategic for PSCs. However, this is difficult for decision-makers, as highly complex situations and conflicting criteria influence such evaluation processes. So, a robust, applicable, and strong methodological frame is required to solve these decision-making problems.Design/methodology/approachTo achieve this challenging issue, the authors develop and apply an integrated entropy-WASPAS methodology with Fermatean fuzzy sets for the first time in the literature. The evaluation process takes place in two stages, as in traditional multi-criteria problems. In the first stage, the importance levels of the criteria are determined by the FF-entropy method. Afterwards, the FF-WASPAS approach ranks the alternatives.FindingsThe feasibility of the proposed model is also supported by a case study where six companies are evaluated comprehensively regarding ten criteria. Herewith, total warehouse capacity, number of refrigerated vehicles, and personnel are the top three criteria that significantly influence the evaluation of pharmaceutical distribution and warehousing companies. Further, a comprehensive sensitivity analysis proves the robustness and effectiveness of the proposed approach.Practical implicationsThe proposed multi-attribute decision model quantitatively aids managers in selecting logistics service providers considering imprecisions in the multi-criteria decision-making process.Originality/valueA new model has been developed to present a sound mathematical model for selecting logistics service providers consisting of Fermatean fuzzy entropy and WASPAS methods. The paper's main contribution is presenting a comprehensive and more robust model for the ex ante evaluation and ranking of providers.

Динамика вылова и современное биологическое состояние сардины иваси Sardinops sagax

Nowadays, after a long period of depression, Japanese sardine (Sardinops sagax) is on the rise. At a high stock level, this species expands its range, migrating to high-productivity Northwest Pacific Ocean areas, where it becomes available to Russian fishery. The article analyzes the long-term catches, as well as provides fishery catches data for 2021. The article also describes distribution and biological status of Japanese sardine during a scientific survey, carried out in the Pacific Ocean waters of the Southern Kuril Islands in October 2019. The article analyzes Japanese sardine nutrition in the feeding grounds.

Implementation of a Pull System – A Case Study of a Polymeric Production System for the Automotive Industry

Abstract This work, developed as a case study, propose, describe, and evaluates an implementation of a pull system in a SME company producing polymeric components for the automotive industry. The production system of the company was based on the push paradigm, which creates high stock levels and high lead times. The main purpose was to develop a pull production system controlled by Kanbans in the painting line. To achieve this goal, this case study demonstrates the application of relevant lean tools, such as, VSM, SMED, Kanban System, Supermarkets and Leveling. Through the SMED’s application, it was possible to reduce the setup times in 38% and make annual earnings of approximately 83000€. The application of a Kanban System, Leveling and Supermarket enabled the WIP’s reduction between injection and painting in 56% and, also, between painting and expedition in 45%. Also, the lead time decreased and the value-added time increased. Thus, this is an exemplary case study for the implementation of a pull system and can be used both by practitioners and researchers interested in this theme.

Prospects for a saturation of humanity’s resource use? An analysis of material stocks and flows in nine world regions from 1900 to 2035

Material stocks in infrastructure, buildings and machinery shape current and future resource use and emissions. Analyses of specific countries and selected materials suggest that material stocks might saturate, which would be important for a more sustainable social metabolism. However, it is unclear to what extent the evidence holds for a wider range of stocks and flows, as well as for world regions or globally.We present an inflow-driven dynamic stock-flow model for 14 bulk materials, end-of-life outflows, recycling, and waste flows for nine world regions from 1900 to 2015, extended with trend scenarios until 2035. Material stocks are growing in all regions and show little signs of saturation yet. In 2015, China used half of global stock-building materials, overtook everyone in stock size around 2012 and grows its stock at ∼8%/year. The Industrialized regions, including the Former Soviet Union, are slowly expanding their high stock levels at ∼1%/year. Stocks in all other regions, inhabited by 60% of the world population, grow at ∼3–5%/year. Inequalities in per capita stocks between regions are large. Trend scenarios suggest potential absolute or per capita stock saturations in some of the industrialized regions, while all other regions are expected to continue high stock growth.Accumulated stocks drive future end-of-life materials and substantial maintenance and replacement requirements. Growing material stocks hamper a potential stabilization or reduction of resource use. Low stock levels in most world regions suggest a crucial window of opportunity for avoiding resource-intensive stock development. In the industrialized regions and especially China, stabilising and reducing resource use requires halting net stock expansion and transforming existing stocks. More materials- and energy-efficient and long-lived stocks which deliver high quality services, and improved reuse, repair and recycling of increasing end-of-life materials to close loops and actually replace virgin resources, are crucial for a more sustainable social metabolism.

Deriving restoration targets from diameter distributions of Dominant Biomass Strata development phases in an old-growth European beech forest

The common stand-level diameter distributions of old-growth forests (i.e., reverse-J or rotated sigmoid) resemble the managerial targets of selection forestry, seemingly making it a potential tool in continuous cover/close-to-nature forestry for the restoration of natural forest structures. Yet while the structures associated with selection forestry are well known, the most prevalent diameter distributions exhibited in natural tree neighborhoods in primeval forests are less well documented. If the structures actually observed in sub-stand patches of natural forest in various forest development phases resemble those targeted by selection forestry, then it may indeed provide useful silvicultural guidance for restoration in future old-growth. To assess this for European beech, the spatial tessellation based floating neighborhood sampling approach was used to delineate natural tree neighbors at the second-order scale (averaging 21 trees over 759 m2 patches) in a primeval European beech forest in the Carpathian Mountains, Ukraine. These neighborhoods were assigned to one of seven Dominant Biomass Strata development phases based on the size class contributing the greatest relative live-tree volume (early Understory, Lower Midstory, and Upper Midstory phases, middle Lower Overstory and Overstory phases, and late Upper Overstory and Emergent phases). Cluster analysis then identified the predominant diameter distribution types (DDTs) in the neighborhoods assigned to each phase. As is typical of primeval beech forest, few neighborhoods were assigned to the early phases (2.1%), proportionally more to the middle phases (25%) and most to the late Upper Overstory phase (50%), with the remainder assigned to the final Emergent (23%) phase. The earliest phases had DDTs with negative exponential (U, LM) or slightly bimodal (UM) forms, but subsequent phases added bimodal (LO), rotated sigmoid (LO-UO), and multimodal (O-E) DDTs. All phases had a very high (50–97%) proportion of trees in the smallest size class, such that no sub-stand patch DDT exhibited a unimodal form, nor did the stand-level distribution resemble a balanced uneven-age distribution. Active management to restore these natural structures may require modifications to selection forestry and include crop-tree (crown) thinning to promote a high (>50/ha) density of large-diameter trees to accumulate high (>500 m3 ha−1 of volume) stocking levels, as well as the creation of mini-gaps (~0.05 ha) to maintain but not necessarily immediately release Understory trees and some small gaps to establish Midstory trees to promote natural multimodal diameter distributions.

Research of material and technical resources inventory management in projects supply chains

The object of research is the processes of material and technical support of projects in the field of supply chain management. One of the most challenging areas faced by logistics and project managers is determining the appropriate level of supply chain inventory management when implementing projects. Today, there is a demand for the development and implementation of dynamic supply chains, the essence of which is to increase the service level by increasing the speed of response to customer requests and flexibility in excess components (high stock levels, unbalanced duration of supply cycles), taking into account the uncertainty of demand.The analysis of the justification of the value of the supply chain, namely of such components as logistics costs, the cost of storing inventories and deficit costs, is carried out. Models of inventory management in the supply chain with centralized and decentralized service are presented. Calculations of the indicators of the standard deviation of demand and the duration of the supply cycle, the values of the cyclic and safety stock are presented. For the situation of centralized service of the resource flow, the influence of the demand dependence on the stock level was investigated.The study used the theory of supply chain management and project management, which made it possible to take into account the variability of demand and the duration of supply. As a result of the work, models of the volume of insurance stocks in conditions of uncertainty in demand and the duration of the supply cycle of resources are proposed. In order to ensure the optimal strategy of resource provision, the concept of «service level» was investigated. The service level of the first kind (cyclical service level) and the service level of the second kind (saturated demand) are considered.The results of this research provide an opportunity to improve project efficiency in the face of volatile demand, reduced product life cycle and increased competition. Such changes require supply chains to develop strategies that are focused on the end user, that is, an integrated supply chain management strategy is required.

Multisite supply planning for drug products under uncertainty

AbstractIn the pharmaceutical industry, the goal of a supply planner is to make efficient capacity allocation decisions that ensure an uninterrupted supply of drug products to patients and to maintain product inventory levels close to the target stock. This task can be challenging due to the limited availability of manufacturing assets, uncertainties in product demand, fluctuations in production yields, and unplanned site downtimes. It is not uncommon to observe uneven distribution of product inventories with some products carrying excess inventories, while other products may be close to a stockout. Maintaining high stock levels can have economic repercussions due to the risk of expiration of unused products (whereas products facing a stockout can adversely affect the treatment regimen of patients). The network complexity of pharmaceutical supply‐chains coupled with regulatory constraints and siloed planning systems force supply planners to rely on manual (error‐prone) decision‐making processes. Such an approach results in suboptimal capacity allocation and inventory management decisions. In this work, we propose a stochastic optimization methodology for the production scheduling of multiple drug products in lyophilization units across multiple sites. The framework leverages information obtained from historical and forecast data to generate scenarios of uncertain parameters (e.g., yield, demand, and downtimes) that can realize in the future. The optimization model determines a product filling schedule that maintains product stock levels close to targets under diverse scenarios. We show that this approach helps in avoiding reactive scheduling and in maintaining a more robust production plan than deterministic procedures (which ignore uncertainty). Specifically, planning under a stochastic optimization approach reduces the number of scenarios under which backlogs are observed and also reduces the magnitude of the backlogs.

Shelf-based scarcity as a cue of luxuriousness: an application of psychophysiology

PurposeThe purpose of this paper is to examine the perception of luxuriousness as a novel underlying mechanism of the shelf-based scarcity effect by using both psychophysiological measures (Study 1) and self-reported measures (Study 2).Design/methodology/approachTwo within-subject experimental designs were conducted to examine the effects of low, medium and high stock depletion levels (i.e. shelf-based scarcity) on consumer responses. In Study 1, facial expression analysis was used to examine consumers’ liking, and left frontal asymmetry brainwaves were used to examine consumers’ approach motivation as a proxy for purchase intention. Study 2 extended the findings with self-reported measures.FindingsIn Study 1, perceived product luxuriousness was found to underlie the shelf-based scarcity effect on facial expressions and left frontal asymmetry brainwaves after controlling for other previously proposed mediators (i.e. product popularity and quality). The shelf-based scarcity effect is only observed between low vs high stock levels, whereas moderate stock level depletion does not evoke the shelf-based scarcity effect. Study 2 used self-reported measures to replicate the effect of shelf-based scarcity on product luxuriousness. However, the findings demonstrated the limitation of self-reported measures to identify a significant spill-over effect of perceived luxuriousness to attitude.Research limitations/implicationsExtending previous literature that relied heavily on self-reported measures, the current research used psychophysiological methods to uncover perceived luxuriousness as a novel underlying mechanism for the shelf-based scarcity effect. Thus, the findings are not only the first to provide psychophysiological evidence of the shelf-based scarcity effect but also to validate perceived luxuriousness as an underlying mechanism of the shelf-based scarcity effect.Practical implicationsThe current findings suggest that the shelf-based scarcity effect is only evoked by high (instead of moderate) levels of stock depletion. The study also shows that shelf-based scarcity does not necessarily signal product popularity, but instead it may serve as a cue of product luxuriousness. Adding to other manipulations of retail spaces that elicit luxury perception (e.g. artwork, sensory delight and themed store atmospherics), this implies that businesses are able to use shelf-based scarcity as a cue to enhance or complement the luxury image or the perception of the brand or product.Originality/valueThe current research is the first study to use psychophysiological techniques to examine perceived luxuriousness as an underlying mechanism of shelf-based scarcity. It also demonstrates that self-report measures are not sensitive to such an effect in comparison to psychophysiological techniques, explaining why perceived luxuriousness has not been previously found to be an underlying mechanism of shelf-based scarcity.

On joint effects of return policy coordination and retail competition

ABSTRACT This paper studies the effectiveness of a return policy as an incentive-aligned coordination mechanism in a decentralised supply chain for short life-cycle products. System performance with regards to profitability and product availability is assessed with a coordinated return policy between the vendor and two competing retailers. Building on the optimal return policy coordination model for short life-cycle products, this paper evaluates individual and joint effects of competition and coordination under the four different settings of competition with and without coordination, and no competition with and without coordination. Results indicate that joint effects are largely contingent on demand structures in the supply chain, whereas individually, return policy coordination displays greater effectiveness in improving fill rates at local retailers by maintaining high stocking levels and competition commands significant impact in improving the system profitability and service level by creating inventory pooling effects between competing retailers.

Material Disposition and Scheduling in Regeneration Processes using Prognostic Data Mining

In the regeneration process of complex capital goods, the definite workload is uncertain until the goods are disassembled and inspected. Due to the uncertainty and long repair lead times, regeneration service providers have difficulties in achieving low regeneration times and meeting delivery dates. Delays in delivery are associated with contractual penalties and keeping a high stock level of spare parts coincides with a high capital tie-up. Therefore, this paper deals with the use of prognostic data mining for long-term material disposition and scheduling to accomplish a high delivery date reliability and low stock levels.

Inventory model for a fresh product when demand depends on freshness, price, inventory level and expiration date under markdown policy

In practice, the demand for a fresh product depends on how fresh it is, therefore, it is important to take expiration date into consideration as it is a key to determine the freshness level of any perishable items. Furthermore, based on marketing and economic theory, selling price plays a crucial role in influencing the demand. Also, a higher inventory level may enhance the profit as it encourages consumers to buy more. Since the demand for fresh product declines over time, markdown policy is offered after some time to increase the demand and profit while reducing the inventory. For this demand function, it may be profitable to maintain a high stock level and the zero ending inventory is relaxed to non-zero ending inventory. Salvage value is incorporated into the deteriorating units. Using differential equations, we propose an economic order quantity model which demand dependent on freshness-expiration date, price and inventory level under markdown policy. We also demonstrate the relationship between markdown time and the annual total profit. Numerical example and sensitivity analysis are used to illustrate the effectiveness of the model.

Hedonic Analysis of Forest Pest Invasion: the Case of Emerald Ash Borer

The emerald ash borer (EAB) was first detected in North America in 2002, and since its introduction, this invasive pest has killed millions of ash trees. While EAB kills native North American ash trees in all settings, its impacts have been especially large in urban areas where ash has been a dominant street tree, especially in residential areas. While some management costs, such as insecticide treatment, tree removal, or tree replacement, are relatively straightforward to compute, the impact that EAB has had on residential property values is less clear. To better understand the economic cost of EAB in urban settings, we conducted a hedonic property value analysis to evaluate the impact of ash tree damages due to EAB infestation on housing sales prices. This study was conducted in the city of Milwaukee, Wisconsin, which had high stocking levels of ash trees prior to EAB’s arrival. The objectives of the study are to investigate: (1) how EAB-infested ash trees affect property values; (2) whether the benefits from healthy ash trees to property value change after arrival of EAB; and (3) whether healthy ash trees located within infested neighborhoods provide the same benefits as the healthy ash trees located outside of infested neighborhoods. In general, our results show that the EAB outbreak has had a negative impact on home values for properties located in close proximity to the ash tree component of the urban forest. This result holds true for neighborhoods where EAB does not yet pose an imminent threat, and is amplified for neighborhoods where EAB has been detected. Our results highlight the early stages of a dynamic economic process that impacts urban residential property owners subject to the risk of EAB or other tree pests and diseases. In general, we find that forward-looking behavior of residential property owners is capitalized into property values during the process of forest pest infestation.

Effectiveness and Sustainability of Grain Price Support Policies in China

We evaluated the effectiveness and sustainability of the grain price support policies in China using the structural break regime switching model. Based on the rice, wheat, and corn monthly price data from 1987 to 2017, we provide strong evidence that the Chinese grain price support policies have been effective in stabilizing the domestic grain price. A structural change occurred in grain price patterns in 2004 when the price support policies were established. Since then, Chinese grain prices have followed a regime with significantly lower volatility. We documented several problems challenging the sustainability of the Chinese grain price support policies in the future, including high economic costs that can trigger high support prices, high public stock level, and high grain import pressure. Our findings shed new light on the functioning of the grain pricing policies and provide useful implications for the market-oriented reforms in the Chinese grain market.

An inventory replenishment system with two inventory-based substitutable products

In a supermarket, two mutually substitutable products with the same price are usually arranged one next to the other such as Coke and Pepsi colas, Campbell and Progresso soups, Breyer and Friendly ice creams, etc. It is evident that a large pile of products (e.g., colas, soups, baked goods, fruits, vegetables, etc.) displayed in a supermarket often induces customers to buy more because of its visibility, variety, and freshness. Hence, high inventory of one product provides consumers various choices, and makes this product preferable. In short, the demand for one product is positively influenced by its displayed stock level while negatively impacted by the displayed stock level of the other product. With the demand being stock-dependent, it may be profitable to maintain high stock level at the end of the replenishment cycle. The common inventory assumption of zero-ending inventory is extended to non-negative ending inventory. Hence, we first propose an inventory model with two inventory-based substitutable products to determine the optimal replenishment time and the ending inventory levels for both products in order to maximize the total annual profit. We then demonstrate that the total annual profit is strictly pseudo-concave with respect to the decision variables, which reduces the search for the global maximum to a local optimum. We also use simple economic interpretations to explain theoretical results. Furthermore, the theoretical results reveal that the optimal replenishment time is whenever one of two substitutable products is sold-out. Finally, numerical examples and sensitivity analyses are presented to highlight several managerial implications.