• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.3347-3352
• /
• 2007

This paper describes a research for the performance improvement of the straight-bladed vertical axis wind turbine. To improve the performance of VAWT, the individual blade pitch control method is adopted. For the wind turbine, CFD analysis is carried out by changing blade pitch angle according to the change of wind speed and wind direction. By this method, capacity and power efficiency of VAWT are obtained according to the wind speed and rotating of rotor, and could predict the overall performance of VAWT. It was manufactured to verify performance of the experimental system that consists of rotor including four blades and base. Furthermore, torque sensor and power generator were installed. Also, active controller which can change the pitch angle of the individual blade according to the wind speed and direction was used.

• Journal of Korean Society of Water and Wastewater
• /
• v.23 no.1
• /
• pp.5-11
• /
• 2009

• Asia-Pacific Journal of Business
• /
• v.13 no.1
• /
• pp.53-74
• /
• 2022

Purpose - This study aims to examine the relationship between flexible Human Resource Management (HRM) and individual ambidexterity and the moderating effect of trust in management. Design/methodology/approach - This study collected 971 survey data from employees in Korea. The Confimatory Factor Analysis (CFA) and the multiple regression analysis were used to analyze the data. Findings - First, the flexible human resource management have a positive effect on individual ambidexterity. Second, trust in management positively moderate the relationship between flexible human resource management and individual ambidexterity. Research implications or Originality - First, this study is critical that it examines individual ambidexterity and antecedent factor, which have not been relatively researched in Korea. This study is meaningful in that it revealed that the individual ambidexterity can be increased through flexible human resource management. Second, individual ambidexterity may vary depending on the characteristics of the human resource management system. Third, it is important to find the boundary condition of trust in management. By finding conditions that enhance the effect of flexible human resource management on individual ambidexterity, it also provides practical implications applicable to companies.

• The Journal of the Korea Contents Association
• /
• v.11 no.12
• /
• pp.774-784
• /
• 2011

The purpose of this study, which was conducted as a part of investigations for vitalizing the School Sheriff system proposed as a means to prevent school violence and promote school safety, was to survey recognition of elementary school parents toward the School Sheriff system and present an improvement scheme for the system. For the study, we selected as the research object a set of parents whose children attended schools with School Sheriffs and then sampled 200 parents out of them with cluster random sampling, before analyzing 189 finally. Validity of the questionnaire is verified by expert council and factorial analysis, and reliability by reliability analysis. Statistical means including chi-square test, t-test and F-test are used. The result of the study as follows : First, necessity of the School Sheriff system varies by individual characteristics. Second, recognition toward the system itself varies by individual characteristics. Third, recognition toward the role that should be played by School Sheriffs varies by individual characteristics. Fourth, there is a difference in perceiving the role and activity of School Sheriffs, Fifth, whether the system helped improving school safety varies by individual characteristics. Sixth, the satisfaction from the School Sheriffs.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.28 no.9
• /
• pp.355-360
• /
• 2016

Continuing to the modeling of heating load, this paper, as the second part of consecutive works, presents LS-SVM (least square support vector machine) based model of winter time apartment hot water supply load in a district heating system, so as to be used in prediction of heating energy usage. Similar, but more severely, to heating load, hot water supply load varies in highly nonlinear manner. Such nonlinearity makes analytical model of it hardly exist in the literatures. LS-SVM is known as a good modeling tool for the system, especially for the nonlinear system depended by many independent factors. We collect 26,208 data of hot water supply load over a 13-week period in winter time, from 12 heat exchangers in seven different apartments. Then part of the collected data were used to construct LS-SVM based model and the rest of those were used to test the formed model accuracy. In modeling, we first constructed the model of district heating system's hot water supply load, using the unit heating area's hot water supply load of seven apartments. Such model will be used to estimate the total hot water supply load of which the district heating system needs to provide. Then the individual apartment hot water supply load model is also formed, which can be used to predict and to control the energy consumption of the individual apartment. The results obtained show that the total hot water supply load, which will be provided by the district heating system in winter time, can be predicted within 10% in MAPE (mean absolute percentage error). Also the individual apartment models can predict the individual apartment energy consumption for hot water supply load within 10% ~ 20% in MAPE.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.1459-1467
• /
• 2011

This paper proposes the effective method to improve the protection from induced lightning Surge by making common grounding from individual grounding. Common grounding under equipotential principle is more effective than individual grounding for lightning Surge protection, and so common grounding is indicated as international technical standard under the AC power supply system with neutral line. So, this paper is to propose the effective way of induced lightning Surge protection method for currently installed power supply system which has no neutral grounded line and individual grounding which are weak for lightning Surge protection. This proposal can improve the power supply system as has neutral line, and improve the grounding system to common grounding system. And also this paper proposes to make effective equipotential system with voltage variable shunting devices for lightning Surge protection.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.5 no.2
• /
• pp.77-85
• /
• 2009

In this paper, we propose data format for smell, taste, touch with speech and vision which can be transmitted and implement a floral scent detection and recognition system. We provide representation method of data of smell, taste, and touch. Also, proposed floral scent recognition system consists of three module such as floral scent acquisition module using Metal Oxide Semiconductor (MOS) sensor array, entropy-based floral scent detection module, and floral scent recognition module using correlation coefficients. The proposed system calculates correlation coefficients of the individual sensor between feature vector(16 sensors) from floral scent input point until the stable region and 12 types of reference models. Then, this system selects the floral scent with the maximum similarity to the calculated average of individual correlation coefficients. To evaluate the floral scent recognition system using correlation coefficients, we implemented an individual floral scent recognition system using K-NN with PCA and LDA that are generally used in conventional electronic noses. In the experimental results, the proposed system performs approximately 95.7% average recognition rate.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2013.10a
• /
• pp.215-218
• /
• 2013

This paper proposes the effective method to improve the protection from induced lightning surge by making common grounding from individual grounding. Common grounding under equipotential principle is more effective than individual grounding for lightning surge protection, and so common grounding is indicated as international technical standard under the AC power supply system with neutral line. So, this paper is to propose the effective way of induced lightning surge protection method for currently installed power supply system which has no neutral grounded line and individual grounding which are weak for lightning surge protection. This proposal can improve the power supply system as has neutral line, and improve the grounding system to common grounding system. And also this paper proposes to make effective equipotential system with voltage variable shunting devices for lightning surge protection.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.15 no.4
• /
• pp.318-328
• /
• 2003

Numerical simulation using computational fluid dynamics (CFD) is performed to calculate the velocities and temperature profiles of air in adjacent to a worker within the individual local air conditioning system. The calculation domain is the space of ㄴ between walls and a worker in the climate room. The fresh air is supplied from the three different inlets located on the right, left and center wall in the climate room. In this study, the calculated data of velocities and temperature profiles of air in the nearest the skin of a worker are used to calculate the PMV (Predicted Mean Vote) for evaluation of thermal comfort of a worker in the local air conditioning system. Because the data of veto-cities temperature profiles of air in adjacent to a worker and the PMV of a worker are the design parameters of the local air conditioning system. The results of calculation show that the fresh air velocity and injection position are closely related to the PMV value. In individual air condition system of ㄴ, the appropriate PMV are obtained when the fresh air velocity and position are 1.0 m/s, throat of a worker and are 1.5 m/s, head of a worker, respectively. The method of numerical calculation is effective to obtain the optimum velocity and position of the fresh air for optimum the PMV and energy saving in individual local air conditioning system.

• Health Policy and Management
• /
• v.24 no.3
• /
• pp.291-300
• /
• 2014

Background: The efficient knowledge management in hospital organization is generally known as the important activities relevant to employees' knowledge sharing behavior and work performance. This research examined factors affecting employees' knowledge sharing behavior and work performance in top 4 university hospitals. This study is based on individual factors such as incentives, reciprocity, behavioral control, and subjective norms. Also, there are organizational factors such as CEO support, learning climate, IT system, rewards system, and trust. Methods: Data was collected from employees who are working at 3 hospitals university in Seoul and 1 university hospital in Gyeonggi-Do through the self-administered questionnaires. A total of 779 questionnaires were analyzed by PASW SPSS ver. 18.0. (SPSS Inc., Chicago, IL, USA). Results: The significant variables affecting knowledge sharing behavior are behavioral control (in individual factor) and CEO, IT system, and trust (in organization factor). Also the significant variables affecting work performance are incentives, reciprocity, subjective norms, and behavioral control (in individual factor) and CEO support, IT system, reward system, and trust (in organization factor). Conclusion: The personality and organization characteristics factors is important to improve knowledge sharing behavior and work performance of hospital employees. Therefore, to make more efficient knowledge management is to build and system knowledge sharing culture, system, and leadership and to develop practical strategies.