• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.2
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• pp.67-72
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• 2003

A partition integrated air supply system can provide highly personalized environmental control. The supply air is brought up through raised floors and supplied to outlets located on the partition panels. The purpose of this paper is to find out the best design of outlets for optimal occupant comfort within a personal task area. Real scale experiments were conducted to allow for comparisons of outlet designs within a personal task area. Experimental results indicate that the location of an outlet is the most critical factor in improving the efficiency of supply air distribution of a personal task area. Thermal characteristic comparisons were made between the under-floor and the partition supply systems. Experimental results suggest that the partition supply system is more efficient than the under-floor supply system in terms of cooling. Such a system allows occupants to personally control their immediate environment, resulting in higher productivity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.2
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• pp.115-121
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• 2001

Recently, the requirement of healthier and more comfortable environment makes the zoning domain more details. However, it has limitation to satisfy the thermal comfort of an individual because of the effect of the heat generation from the OA machine and partitions in indoor room. In this paper, we certify the validity of task-ambient air-conditioning system that has been developed as a new concept of personal air-conditioning system, and specify design strategies for more efficient task-ambient air-conditioning system with a specification guided by indoor environmental characteristics analyzed through experiment data. In this experiment, we changed the temperature and the quantity of air-flow in task domain to understand characteristic behavior of the thermal environment and investigate the possibility of energy saving. The experiment result is that the environment of the task area depends on the condition of supply air, and though the airflow of the low temperature is supplied with the ambient area, the personal environment and the efficiency of energy saving are improved by controlling the temperature and the quantity of the air shot around the task domain.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.4
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• pp.252-261
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• 2001

Room air flow and temperature distribution was numerically investigated where a PAC(personal air conditioning) system was installed. The calculated results were compared with those from experiments. The effects of the important operation parameters such as the air flow rate, velocity, and temperature at the diffuser on the thermal performance of the system were studied. The possibility of energy saving using the PAC system was verified from the results, It was shown that the warm air from the diffuser could not spread over the whole task area if the inlet temperature was too high.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.217-223
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• 2012

Objectives: This study was conducted to evaluate personal and area exposure of airborne nicotine during harvest and weaving tasks in tobacco farms. Methods: Nicotine was measured with NIOSH method 2551 and Passive sampler which was validated in previous papers for area and personal sampling. Results: The average (geometric mean) concentrations of nicotine with two different tasks in personal sample were 6.5 ${\mu}g/m^3$ (harvest), 32.6 ${\mu}g/m^3$ (weaving) and in area sample were 0.8 ${\mu}g/m^3$ (harvest), 57.2 ${\mu}g/m^3$ (weaving). There was significant difference in area sample between harvest and weaving task (p=0.000). Also, there was significant difference with personal sample (p=0.000). Conclusions: It was found that weaving task should be considered to be the first priority for reducing nicotine exposure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.985-988
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• 2005

The international standards of high-rate WPAN (Wireless Personal Area network) are under development by IEEE802.15 WPAN TG3 (Task Group 3). The study area of TG3 mainly consists of three parts: high rate physical and media access control layer in 2.4GHz ISM (Industrial Scientific Medical) non licensed frequency band; an alternative high rate physical layer by using UWB (Ultra Wide Band); and another alternative high rate physical layer based on millimeter wave. This paper describes the standardization trends of UWB and millimeter wave.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.2
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• pp.106-114
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• 2001

The office environment of the building has been significantly changed and the office automation(OA) for productivity improvement and efficiency has proceeded. According to thee trends, the concept of office environment was transferred from conventional \"working space\" to \"living space\" or \"creative space\". Thus, occupants in office building have demanded more comfortable and advanced task environment. The objective of this paper is to evaluate the indoor environment of working space with personal air conditioning system using the measurements of environmental comfort parameters and the questionnaire survey of occupants、 thermal sensation response to the environment.n response to the environment.

• Journal of Internet Computing and Services
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• v.13 no.6
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• pp.17-24
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• 2012

The purpose of this study is to test the effect of personal communication activities using smart phone instant messenger during normal office hours on job performance in the workplace. To do this, empirical data were collected by conducting a field survey of smart phone users, and structural equation model was used for the purpose of analyzing the data acquired by the survey. A structural equation model was designed and constructed by such factors like personal instant messaging with the outside friends and co-workers on job performance. In addition, task characteristics set as a moderating effect between personal instant messaging with the outside friends/co-workers and job performance. The results of the analysis are summarized as follows; First, personal instant messaging with the outside friends generally has a negative effect on job performance, in addition in high task interdependence area the former has more effect on the latter. Second, personal instant messaging with co-workers has a positive effect on job performance.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.297-305
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• 2006

High-rate wireless personal area network (HR-WPAN) has been standardized by the IEEE 802.15.3 task group (TG). To support multimedia services, the IEEE 802.15.3 TG adopts a time-slotted medium access control (MAC) protocol controlled by a central device. In the time division multiple access (TDMA)-based wireless packet networks, the packet scheduling algorithm plays a key role in quality of service (QoS) provisioning for multimedia services. In this paper, we propose an adaptive cross-layer packet scheduling method for the TDMA-based HR-WPAN. Physical channel conditions, MAC protocol, link layer status, random traffic arrival, and QoS requirement are taken into consideration by the proposed packet scheduling method. Performance evaluations are carried out through extensive simulations and significant performance enhancements are observed. Furthermore, the performance of the proposed scheme remains stable regardless of the variable system parameters such as the number of devices (DEVs) and delay bound.

• The Journal of Korean Academic Society of Nursing Education
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• v.10 no.1
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• pp.44-53
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• 2004

Purpose: This research was to grasp task performance of the Preceptor and to offer the basic data to a Preceptorship establishment. Method: 208 Preceptors which have been working at three 3rd medical institutions of Seoul. A task performance degree of Preceptor has been measured using a questionnaire which modifying and supplementing Schiwirian's tool(1974) The collected data was analyzed into description statistics, t-test and ANOVA through the SPSSWIN program. Result: The task performance degree was a $4.06{\pm}.51$ score. Personal relations and understanding was the highest area with a $4.31{\pm}.50$ score and patient education was the lowest area with a $3.69{\pm}.58$ score. the service career as a nurse is more than nine years(F=3.122, P=.027), worked as the Preceptor for more than five years to less than a seven year period(F=3.499, P=.016), the number of new nurses to educate as a Preceptor is more than five(F=3.509, P=.009), it has been evaluated as a good task performance. Conclusion: The selection of competent Preceptor and the development of the education program for Preceptors are required to deal with their task effectively. Above all, the task achieved successfully can be contributed to a Preceptorship establishment.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.2
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• pp.49-54
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• 2016

The purpose of this study is to analyze the indoor temperature distribution of a room controlled by a personal and portable cooler. As an energy saving strategy, the personal air-conditioning or task conditioning system was developed and installed in office buildings in the 90 s. Many research results regarding the personal air-conditioning (PAC) system were focused on thermal comfort, localized ventilation efficiency and energy savings. However, the conventional PACs were only developed for application in office buildings. In this study, as a type of PAC, a portable cooler was analyzed in terms of indoor temperature distribution changes with the passage of time. The measurement was performed in a bedroom in an apartment house. The results showed that indoor temperature was controlled at about $24^{\circ}C$ around the human body. However, the ambient zone up to 1.5 m away from the the human body stayed at about $27.5^{\circ}C$.