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In the residential sector, householders play an active role in regulating the indoor climate via diverse control measures such as the operation of air-conditioners or windows. The main research question asked in this paper is whether control decisions made by householders are rational and effective in terms of achieving comfort and energy efficiency. Based on a field study in South Korea, this paper explores how a HVAC control strategy for high-rise apartment buildings can affect occupant comfort and adaptive behavior. Two different control strategies: (1) occupant control (OC), where occupants were allowed to freely operate the HVAC system and (2) comfort-zone control (CC), where the operation of the HVAC system was determined by the researcher, based on a pre-defined comfort zone, were applied to, and tested within the participating households in summer. The impact of the two control strategies on indoor thermal environments, thermal comfort, and occupant adaptive behavior were analyzed. We find that the CC strategy is more energy/comfort efficient than OC because: (1) comfort was be achieved at a higher indoor temperature, and (2) unnecessary control behaviors leading to cooling load increase can be minimized, which have major implications for energy consumption reduction in the residential sector.

Occupants of apartment blocks tend to wear less clothing and exhibit lower metabolic rates than occupants of other building types. Further, the use of air conditioning systems to maintain certain comfort levels within living spaces automatically generates financial cost. Therefore, in this study, an acceptable comfort range that differs from the conventional normative comfort range was established. A thermal comfort control method was designed to satisfy both the economic and comfort requirements, and experiments were conducted accordingly. Subsequently, empirical data on cooling were obtained via surveys and measurements and employed to derive regression equations for the thermal sensation vote, comfort sensation vote, and percentage dissatisfaction, which indicate occupant comfort. The derived regression equations were used to graph the comfort range, and the overlap region was plotted on a psychrometric chart to enable identification of an acceptable comfort zone. The suggested acceptable comfort zone, which applies to apartment blocks in Korea, is outside the conventionally recommended comfort zone and can satisfy various occupant preferences, contribute to reducing energy consumption, and facilitate maintenance of comfortable living environments.

In order to achieve comfort, or to remove discomfort, building occupants constantly interact with the indoor environment through various adaptive behaviors. The purpose of this study is to better understand the adaptive thermal comfort mechanisms by investigating the interrelationship between the indoor thermal environments, the expectation of the occupants, and their behavioral adjustments in residential contexts. Eleven households in South Korea participated in our field experiments performed during summer months (June, July and August) between 2015 and 2017. The indoor thermal environmental parameters, occupants’ subjective evaluations of thermal comfort, and their operational patterns of air-conditioners were monitored simultaneously. On average 1512 datasets from each participating household and a total of 16,632 datasets were collected and analyzed. Our analysis focused on understanding both the temporal dimension (i.e. duration of thermal discomfort episodes) and the intensity of stimuli (i.e. deviation from the comfort zone) both before- and after the participants’ decision on the use of air-conditioners. The study proposes the constructs of ‘discomfort capacity’ and ‘comfort restoration’ as multi-dimensional indices to better understand the triggering mechanisms for household air-conditioner usage. Using these indices, the study quantified householders’ tolerance of thermal discomfort events before they resort to air-conditioning. The findings have practical implications in setting up dynamic control strategies that are more responsive to occupant real-time comfort demands.

Objectives This study was to evaluate the performance of the newly developed information system (IS) implemented on July 1, 2014 at three public hospitals in Korea. Methods User satisfaction scores of twelve key performance indicators of six IS success factors based on the DeLone and McLean IS Success Model were utilized to evaluate IS performance before and after the newly developed system was introduced. Results All scores increased after system introduction except for the completeness of medical records and impact on the clinical environment. The relationships among six IS factors were also analyzed to identify the important factors influencing three IS success factors (Intention to Use, User Satisfaction, and Net Benefits). All relationships were significant except for the relationships among Service Quality, Intention to Use, and Net Benefits. Conclusions The results suggest that hospitals should not only focus on systems and information quality; rather, they should also continuously improve service quality to improve user satisfaction and eventually reach full the potential of IS performance.

The main purpose of this study was to investigate the effect of the factors which cause the patients to choose hospital from the view of Christian missionary hospital. The subjects were 194 inpatients and 202 outpatients of the K Medical Center in Busan. The research had been conducted from 20 June to 31 July in 2013. The major results demonstrated that the medical and social services image factors strongly affected to the satisfaction and selectivity of patients. Social role image of religious medical institution should be considered important and it seems beneficent in CRM(Customer Relationship Management) based on this results.

The principal objective of this study was to evaluate the consumption behavior and perceptions of environmentally-friendly agricultural products (EAPs) according to the lifestyles of housewives in the Jeonbuk area, Korea. Self-administered questionnaires were collected from 267 housewives. Frequency analysis, chi-square, one-way ANOVA, factor analysis, and cluster analysis were used to analyze the data. Three clusters were obtained from the cluster analysis of LOHAS and wellbeing-related lifestyle: Cluster 1 "LOHAS-pursuit group", Cluster 2 "wellbeing-progress group", Cluster 3 "Utility-pursuit group". Of the housewives who were of LOHAS-pursuit group, about 50% were over 40 years old and had a professional job with a high household income. They had a high level of understanding about EAPs and purchased the highest percentage of EAPs among the groups. The housewives who were of the wellbeing-progress group, over 83% were between the ages of 30 and 40. Their consumption behaviors were very similar with that of the LOHAS-pursuit group, but the household income was lower. Of the housewives who were of the utility-pursuit group, about 63% under 30 years old. Their household income and level of understanding about EAPs were the lowest among the groups. They less interest in EAPs in comparison with other groups. For housewives' to choose EAPs properly, information and consumer education on these products, according to their lifestyles is necessary.

High air-tightness and high heat-insulation of buildings cause lack of fresh air inside the buildings. Operating the ventilation system in an apartment house may improve the indoor air quality, but may generate the problems, such as high airconditioning load and cold draft. In order to improve the indoor air quality while maintaining pleasant heat environment to a certain level, it is necessary to consume energy for cooling and heating. Energy Recovery Ventilation system (here in after “ERVs”) is the typical way to minimize the consumption of energy. To solve the problem, the installation of ERVs has been made mandatory for new apartment buildings that are constructed in the Republic of Korea. The interest in ERVs has increased recently in that the System is viewed as helping to: 1. Reduce energy costs of heating and cooling apartment buildings, which costs claim a significant portion of apartment building management budgets, and 2. Secure appropriate levels of ventilation in such buildings. Despite the enthusiasm, the lack of efficient implementation of ERVs persists. Based on the rationale, this study realized the optimal operating algorithm for ERVs. The study took actual data on temperature and humidity; operation status on air conditioners and ERVs; electricity consumptions; and PMV. The study analyzed airconditioning ventilation loads and energy-saving effects related thereto according to the optimal operating algorithm for ERVs. The results showed statistically significant figures that contribute to the reduction of loads and energy costs. Implications of the study include: 1. Introducing the optimal ERVs to apartment buildings will likely help the residents and building managers to better respond to changes occurring to the outside environment and to the inside loads being applied to indoor HVAC systems; and 2. Implementation of ERVs would likely help reduce the loads being imposed on the HVAC systems in apartment buildings.

Electricity demand is surging every year in Korea owing to economic growth and a subsequent increase in energy demand. In particular, heavy cooling load during summer and high heating load during winter to fight heat wave and cold wave, respectively, which are allegedly caused by the unpredictable climate change, trigger electricity peak and unstable energy supply as a result. Integrated Energy Business (IEB), which is known as regional heating overseas, draws attention as a distributed energy that can address such structural issues as blackout in the central supply system. Yet, electricity charge lower than production cost, realistic challenges in direct sales of energy production facilities and energy loss incurred from transporting energy from supply facilities to receiving ends keep it from rooting down in Korea. This study compared number of households, number of buildings to which electricity is supplied, capacity of supply facilities, amount of fuel and production and sales volume of energy in order to determine appropriate supply capacity of heat and electricity in regional cooling/heating areas and industrial complexes based on Korea's IEB operation. Also, the study grouped IEB systems according to sizes of energy supply facilities and compared them so as to suggest an appropriate size of IEB and an effective supply system that can be considered for new housing site projects or re-developed regions.

Based on Super Grade hotels that have high energy consumption per unit area cause a massive amount of load. This work analyzed the properties of electricity consumption by using electricity load data. It analyzed the correlation of reducing each amount of electricity load and electricity peak load through the peak demand management and energy efficiency improvement of the large hotels. Based on the reduction in the total amount of electricity load, this work proposed a plan to reduce electricity peak load.