Search results

Dynamic lot sizing is the problem of determining the quantity and timing of ordering items while satisfying the demand over a finite planning horizon. This paper considers the problem with two practical considerations: minimum order size and lost sales. The minimum order size is the minimum amount of items that should be purchased and lost sales involve situations in which sales are lost because items are not on hand or when it becomes more economical to lose the sale rather than making the sale. The objective is to minimize the costs of ordering, item , inventory holding and lost sale over the planning horizon. To solve the problem, we suggest a heuristic algorithm by considering trade-offs between cost factors. Computational experiments on randomly generated test instances show that the algorithm quickly obtains near-optimal solutions.

The Korean securities and derivatives markets, which offer such internationally renowned products as KOSPI 200 futures and options, along with proliferation of such derivative securities as ELS have offered an opportunity for investors to manage risk and select investment products for all different future prospects. However, if the market was to face with a shock in the magnitude of, for instance, the Black Monday of October 1987, possibly the market may trap into total confusion as the increased demand for portfolio insurance could enlarge the volatility of both cash and derivatives markets‘

In this paper we estimate the amount of settlement fund required in the Korean securities and derivatives markets via stress testing if the market falls into an extreme case of vulnerability. The required settlement fund was estimated using two step procedures. Firstly, we estimate market risk applying three different approaches, namely, 99% VaR. EVT and the historical time periods when the market exhibited extreme volatility. We found that from six member companies to as many as 16 companies could face settlement failures, which are represented by having the operating-income-to-capital ratio of less than 100%.

Secondly‘ after estimating each company's settlement amount and summing them to forecast the aggregate amount of settlement fund, it was found that at maximum 350 billion won was required for settlement fund. However, as OTC products become more popular in the near future, the required settlement fund will be larger. Especially if the CCP takes over the OTC market in terms of settlement and clearing, it is expected that the emergency settlement requirement will even become larger.

This study aims to explore how perceived usefulness and perceived ease of use affect users' sensory experience and behavioral experience in the metaverse context, and explore the significance of building a metaverse platform for companies, and provide management enlightenment for corporate development.

Data were collected from 329 online participants and analyzed using structural equation modeling and hierarchical regression.

Perceived usefulness and ease of use have a significant influence on customer sensory experience and behavioral experience in the metaverse. Sensory experience mediates the influence of perceived usefulness and availability on behavioral experience. Social presence positively moderates the influence of both usefulness and ease of use on sensory and behavioral experience. In other words, perceived usefulness and perceived ease of use in the metaverse situation affect sensory experience through social presence, and then affect behavioral experience.

This research clarifies the effect of usefulness and ease of use on customer sensory and behavioral experience. It confirms the positive moderating role of social presence and the mediating role of sensory experience in the influence pathway between perceived usefulness, ease of use, and behavioral experience. From the perspective of management, this study provides theoretical support for the positive impact of corporate metaverse platform building on customer brand experience in the future, and provides impetus for companies to pay attention to improving the usefulness and ease of use of their metaverse platform.

This paper aims to investigate the impact of corporate dividend policy on the capital structure in the Korean stock market. To distinctly discern the voluntariness of changes in corporate dividend policy, we analyze companies that, following a substantial increase, do not reduce dividends for the subsequent two years or, after a significant decrease, do not raise dividends for the following two years. Our empirical findings indicate that companies that increase dividends experience a significant decrease in both book and market leverage, even after controlling for variables such as target leverage ratios. This result suggests that a large increase in dividends can effectively reduce information asymmetry, leading to a lower cost of equity. On the contrary, after a decrease in dividends, both book leverage and market leverage significantly increase, revealing a symmetric relationship between dividend policy and capital structure. In conclusion, large dividend increases in Korean companies not only reduce information asymmetry but also lower the cost of equity capital, resulting in observable changes in the leverage ratio.

This study aims to identify the consumption mechanism by which consumers’ materialism creates purchase intentions for luxury athleisure products through impression management purchase motivation and to verify the moderating effect of sustainability in this mechanism.

This study conducted a scenario-based online survey by dividing into two groups according to the sustainability of luxury brand products (non-sustainable vs sustainable). Structure equation modeling (SEM) was performed to verify the hypotheses.

The SEM results showed that materialism has a positive effect on the purchase intention of luxury athleisure products. It was also confirmed that impression management purchase motivation mediates the relationship between materialism and purchase intention. As a result of examining the moderating effect of sustainability, materialism directly affects purchase intention for unsustainable products, but only indirectly affects sustainable products through impression management purchase motivation.

This study expanded the research on luxury brands by providing the consumption mechanism of luxury athleisure considering sustainability.

Luxury brand marketers should strategically motivate consumers to purchase by activating materialistic tendencies such as ownership and display for general athleisure products and using impression management purchase motivation for sustainable products.

This study explored unresolved research areas on the consumption mechanism of luxury athleisure by identifying the mediating role of impression management purchase motivation in the relationship between materialism and luxury consumption and exploring the moderating role of sustainability.

The purpose of this paper is to investigate an integrative model that explores the influence of knowledge-sharing enablers (social capital (SC), including structural, relational, and cognitive SC) on knowledge-sharing (KS) processes (KS behaviors: knowledge collecting (KC) and knowledge donating (KD)) as well as a further superior KS outcome (organizational performance).

The survey was administered in 14 top tier five-star hotels in Seoul, Korea. Employees of the hotels participated in the survey; 486 surveys were used to investigate a research model and hypotheses using a path analysis.

The research confirmed the importance of SC in the context of KS from the resource-based view. The paper provides empirical evidence that structural, relational, and cognitive SC affected KC and KD, which in turn influenced organizational performance. Interestingly, whereas cognitive SC has the strongest effect on employees' KC, relational SC has the strongest effect on employees' KD. The impact of employees' KC on organizational performance appears to be stronger than that of KD.

The relationships among KS enablers, processes, and organizational performance may provide a clue regarding how hotels can promote KS culture, which focuses on the social dynamics derived from interpersonal and group relationships to boost their performance by increasing employees' willingness to collect knowledge from and donate knowledge to colleagues.

This study explores the under-researched subject of SC with regard to KS and their roles in promoting organizational performance within a hospitality industry context. The study is among the first to examine SC as an organizational resource, two distinctive types of KS behaviors as an organizational capability, and organizational performance from both an integrative (KS enablers-processes-outcomes framework) and resource-based view of the firm's perspective simultaneously. Especially, this study identifies the specific mechanism of two distinctive types of employees' KS behaviors, such as KC and KD, between SC factors and organizational performance.

The purpose of this study is to examine the influences of creativity, psychological ownership (PO) and perceived organizational support (POS) on knowledge creation, using the integrative systems model of creativity.

A survey was used to collect data from 188 workers in Korean public service organizations. Analyses, including bootstrapping and hierarchical regression analysis, were performed to determine the mediating effect of PO and also the moderating and the moderated mediating effects of POS.

The results showed that PO mediates partially between creativity and knowledge creation and that POS moderates the relationship between PO and knowledge creation. Notably, the moderated mediating effect of POS was only significant when employees had a high level of POS.

The findings suggest that creativity dissemination requires employees’ social consciousness, collaborative interactions and organizational support. The results imply that human resource development (HRD) practitioners need to cultivate the creativity capacity in the organization.

This study discusses the effects of PO and POS on creative performance, which HRD professionals and organizational leaders draw attention to for organizational development. Implications for organizational composition and interventions to enhance creative performance are provided.

Textual information about restaurants, such as online reviews and food categories, is essential for consumer purchase decisions. However, previous restaurant recommendation studies have failed to use textual information containing essential information for predicting consumer preferences effectively. This study aims to propose a novel restaurant recommendation model to effectively estimate the assessment behaviors of consumers for multiple restaurant attributes.

The authors collected 1,206,587 reviews from 25,369 consumers of 46,613 restaurants from Yelp.com. Using these data, the authors generated a consumer preference vector by combining consumer identity and online consumer reviews. Thereafter, the authors combined the restaurant identity and food categories to generate a restaurant information vector. Finally, the nonlinear interaction between the consumer preference and restaurant information vectors was learned by considering the restaurant attribute vector.

This study found that the proposed recommendation model exhibited excellent performance compared with state-of-the-art models, suggesting that combining various textual information on consumers and restaurants is a fundamental factor in determining consumer preference predictions.

To the best of the authors’ knowledge, this is the first study to develop a personalized restaurant recommendation model using textual information from real-world online restaurant platforms. This study also presents deep learning mechanisms that outperform the recommendation performance of state-of-the-art models. The results of this study can reduce the cost of exploring consumers and support effective purchasing decisions.

关于餐厅的文本信息, 如在线评论和食品分类, 对于消费者的购买决策产生至关重要。然而, 先前的餐厅推荐研究未能有效利这些文本信息去预测消费者喜好。本研究提出了一种新颖的餐厅推荐模型, 以有效估计消费者对多个餐厅属性的评估行为。

我们从 Yelp.com 收集了来自25,369名消费者对 46,613 家餐厅的 1,206,587 条评论。利用这些数据, 我们通过结合消费者身份和在线消费者评论生成了消费者偏好向量。然后, 我们结合了餐厅身份和食品分类来生成餐厅信息向量。最后, 考虑到餐厅属性向量, 本研究调查了消费者偏好和餐厅信息向量之间的非线性交互关系。

我们发现, 所提出的推荐模型相比于之前最先进的模型表现出更优秀的性能, 这表明结合消费者和餐厅的各种文本信息是预测消费者喜好的基本因素。

据我们所知, 这是第一项利用来自真实在线餐厅平台的文本信息开发个性化餐厅推荐模型的研究。本研究还提出了胜过最先进模型的深度学习机制。本研究的结果可以降低探索消费者行为的成本并支持有效的购买决策。

This study aims to examine the effects of contractual fairness and power sources on the relationship between the buyer and supplier on the innovation performance of the supplier. The mediating role of social capital accumulation between fairness, power and innovation performance was empirically explored.

Hypotheses were developed to investigate the relationships between supply chain fairness, power sources, social capital and innovation performance. Using structural equation modeling, the hypotheses were tested on data of 209 responses collected from supplying firms in South Korea.

This study finds that supply chain contractual fairness and referent power use contribute to the innovation performance of the supplier through social capital accumulation between the buyer and supplier. Coercive power, in contrast, impedes the performance improvement of the supplier.

This study provides supply chain practitioners, academics and policy-makers with guidance on how to facilitate and enhance innovation capabilities and performance across the supply chain. By applying social capital theory, this study also provides theoretical underpinning of the literature on supply chain fairness, power and innovation.

This study aims to systemically evaluate morphological printing errors between computer-aided design (CAD) and reference models fabricated using two different three-dimensional printing (3DP) technologies with hard and soft materials.

The reference models were designed to ensure simpler and more accurate measurements than those obtained from actual kidney simulators. Three reference models, i.e. cube, dumbbell and simplified kidney, were manufactured using photopolymer jetting (PolyJet) with soft and hard materials and multi-jet printing (MJP) with hard materials. Each reference model was repeatably measured five times using digital calipers for each length. These values were compared with those obtained using CAD.

The results demonstrate that the cube models with the hard material of MJP and hard and soft materials of PolyJet were smaller (p = 0.022, 0.015 and 0.057, respectively). The dumbbell model with the hard material of MJP was smaller (p = 0.029) and that with the soft material of PolyJet was larger (p = 0.020). However, the dumbbell with the hard material of PolyJet generated low errors (p = 0.065). Finally, the simplified kidney models with the hard material of MJP and soft materials of PolyJet were smaller (p = 0.093 and 0.021) and that with the hard material of PolyJet was opposite to the former models (p = 0.043).

This study, to the best of authors’ knowledge, is the first to determine the accuracy between CAD and reference models fabricated using two different 3DP technologies with multi-materials. Thus, it serves references for surgical applications as simulators and guides that require accuracy.