Sungyong Choi

We consider a multiproduct risk-averse newsvendor under the law-invariant coherent measures of risk. We first establish several fundamental properties of the model regarding the convexity of the problem, the symmetry of the solution, and the impact of risk aversion. Specifically, we show that for identical products with independent demands, increased risk aversion leads to decreased orders. For a large but finite number of heterogeneous products with independent demands, we derive closed-form ap

We consider a multi-product newsvendor using an exponential utility function. We first establish a few basic properties for the newsvendor regarding the convexity of the model and monotonicity of the impact of risk aversion on the solution. When the product demands are independent and the ratio of the degree of risk aversion to the number of products is sufficiently small, we obtain closed-form approximations of the optimal order quantities. The approximations are as easy to compute as the risk-

The purpose of this paper is to examine the relationship between emotional, managerial, and intellectual competence of team members, which refer to the LDQ (Leadership Development Questionnaire) and impact on project success. (1) Background: Large and complex projects are being conducted in a dynamic business environment. The need for capabilities and managerial aspects of participants of the project for business performance increases. (2) Methods: A questionnaire survey was conducted on 164 pro

The purpose of this study is to empirically confirm the importance of learning orientation in the operation of start-up companies. In the literature, it is well known that this learning orientation plays a big role in improving the performance of start-ups by cultivating organizational members’ capabilities in detail, encouraging active learning, and creating new knowledge. To this end, a business model innovation framework for start-ups was established by empirically validating the th

Despite the stereotype that secondary flow fields induced by surface grooves are effective for microfluidic mixing and increase the entropy of different fluid flows, many efforts have been made to utilize the grooves for particle separation and focusing, decreasing the entropy of particle distribution. As part of these efforts, hydrophoresis has been proposed to define deterministic particle trajectories in grooved microchannels. Due to the simple, cloggingfree, and high-throughput characteristi

[Purpose] The purpose of this study was to examine the effects of cervical traction treatment, cranial rhythmic impulse treatment, a manual therapy, and McKenzie exercise, a dynamic strengthening exercise, on patients who have the neck muscle stiffness of the infrequent episodic tension-type (IETTH) headache and frequent episodic tension-type headache(FETTH), as well as to provide the basic materials for clinical interventions. [Subjects] Twenty-seven subjects (males: 15, females: 12) who were d

Information and Communications Technology (ICT) network readiness competency improves service quality and provides efficient service in implementing successful e-governments. By confirming ICT network readiness of e-governments, it must be redesigned using limited resources effectively to achieve realistic goals. When ICT investment and economic performance are featured, e-government's network readiness competency improves potential demand, supply, and service maturity. It reflects information t

This study aims to provide an optimization model for operational efficiency in individual firms with cap-and-trade carbon emissions regulation. In addition, this study assumes that customers’ demand takes a probability distribution. Under this circumstance, our intention is to draw theoretical and policy implications for carbon emissions regulation by setting and analyzing newsvendor models in which the decision maker is loss-averse for her risk preference. Then, we formulate two loss-averse new

A multiport dryer design concept that could create breakthroughs in the drying of pulp and paper is under development. The feasibility of this novel concept was demonstrated in a proof-of-concept test. Experiments were performed in a specially designed test apparatus to investigate the condensing heat-transfer characteristics of a single channel (representative of a multiport cylinder dryer) under typical operating conditions. The experimental results showed that multiport cylinder-dryer technol

Developing countries face significant challenges in achieving energy stability due to disruptions in their energy supply chains, which jeopardise their sustainability and survivability. Addressing these issues requires careful consideration of public funding in the energy sector and the design of a robust electricity infrastructure. This study aims to identify long-term infrastructure investment strategies that can strengthen the viability of the energy supply network in developing countries, ev

Korean healthcare service is divided into conventional medicine and traditional Korean medicine (TKM). This cross-sectional study compared the older population (65 years and older) with two groups of the general population (19–50 years and 51–64 years) to understand the current patterns in the use of TKM services by the older population. Using data from the 2017 National Survey of TKM Usage, we analyzed the main purpose and diseases or symptoms for TKM use, the reason for choosing TKM over other

The COVID-19 pandemic has affected smart city operations and planning. Smart cities, where digital technologies are concentrated and implemented, face new challenges in becoming sustainable from social, ecological, and economic perspectives. Using text mining methodologies of topic modeling and network analysis, this study aims to identify keywords in the field of smart cities after the pandemic and provide a future-oriented perspective on the direction of smart cities. A corpus of 1882 papers w

Objective : This study aimed to analyze the utilization of Korean Medicine clinics, and high-frequent diseases by sex, age, and region of outpatients and inpatients Methods : The data for this study were "Report on Usage Patterns of Korean Medicine Clinics" issued by the Ministry of Health and Welfare in 2008. Descriptive analysis and correspondence analysis were used to find the patterns of patient’s utilization by sex, age and region Results: Diagnosis and examination methods mostly consisted