• Journal of Life Science
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• v.22 no.7
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• pp.871-879
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• 2012

Polyploids are a potentially important germplasm source in seedless citrus breeding program. Seedlessness is one of the most promising traits of commercial mandarin breeds that mandarin triploid hybrids possess permanently. The formation of new constant triploid hybrids can be recovered through diploid species hybridization from the fusion of divalent gametes at low frequencyor intra-and inter-ploidy crosses. However, extensive breeding work based on small $F_1$ hybrid seeds developed is impossible without a very effective aseptic methodology and ploidy event. In this study, in vitro embryo culture was employed to recover natural hybrids from monoembryonic diploid, open-pollinated mandarin. Flow cytometry was used to determine ploidy level. A total of 10,289 seeds were extracted from 792 fruits having approximately 13 seeds per fruit. Average frequency of small seeds developed was 7.1%, while the average frequency of small seeds per fruit were: 8.9% for 'Clementine' 10.2% for 'Harehime' 2.6% for 'Kamja' 3.1% for 'Pyunkyool' 2.8% for 'Sadookam' and 7.0% for 'Wilking' mandarin. Average size of a perfect seed was $49.52{\pm}0.07mm^2$ ('Clementine') while the small seed measured $7.95{\pm}0.04mm^2$ ('Clementine'), which was about 1/6 smaller than the perfect seed. In total, 731 small seeds were obtained and all of them contained only one embryo per seed. The efficiency of 'Clementine' was 14 times higher than 'Wilking' and more than 109 times higher than 'Pyunkyool'. The basic information on spontaneous polyploidy provides for the hybridization of constant triploids and increases the efficiency of conventional cross.

• The Korean Journal of Emergency Medical Services
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• v.13 no.1
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• pp.97-114
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• 2009

Purpose : This study was performed to identify the knowledge and educational wants for first-aid and its related factors of senior students in elementary schools. Methods : From July 11-25, 2008, this study surveyed 437 elementary school students using a structured questionnaire. Result : Of the study subjects, 47.6% of the subjects had experienced first-aid conditions 25.4% had injuries, 11.0% had indigestion, 10.5% had sprains, 6.2% had acute abdominal pains, 5.9% had brash, and 5.7% had fractures. The experience rates of first-aid conditions were significantly different according to gender, mothers' educational status, means of school attendance and amount of exercise. The experience rate of first-aid education was 71.4%. There was a significant difference with grade, and school reports. They had education about cardiopulmonary resuscitation (52.5%), injury treatment and desmology(48.7%) in a good order. The score of knowledge about first-aid was $13.95{\pm}4.1$ and it was converted on the basis of 100 points, the results were below 50points, and there was a significant difference in grades. Educational wants for first-aid was 64.3%, and as a result of multi-logistic regression analysis of characteristics relating to educational wants, there was a significant difference between gender, grade, mothers' educational status, and amount of exercise. Conclusion : The rate of first-aid experience of elementary school students was high, but as their recognition and knowledge on first-aid was low, the importance of first-aid education and educational wants should be reflected for practical and organized education.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.4
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• pp.398-404
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• 2015

In this paper, we describe the design and performance of a prototype multi-rotor unmaned aerial vehicle( UAV) platform featuring an inertial measurement unit(IMU) based autonomous-flying for use in bluetooth communication environments. Although there has been a fair amount of study of free-flying UAV with multi-rotors, the more recent trend has been to outfit hexarotor helicopter with gimbal to support various services. This paper introduces the hardware and software systems toward very compact and autonomous hexarotors, where they can perform search, rescue, and surveillance missions without external assistance systems like ground station computers, high-performance remote control devices or vision system. The proposed system comprises the construction of the test hexarotor platform, the implementation of an IMU, mathematical modeling and simulation in the helicopter. Furthermore, the hexarotor helicopter with implemented IMU is connected with a micro controller unit(MCU)(ARM-cortex) board. The micro-controller is able to command the rotational speed of the rotors and to get the measurements of the IMU as input signals. The control simulation and experiment on the real system are implemented in the test platform, evaluated and compared against each other.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.270-278
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• 2009

Most of previous studies on civil servants' stress factors and job satisfaction have been focused on low job satisfaction caused by stress from role relations and human relations. In case of fire officers, however, their stress is expected to be influenced by their unique job characteristics such as risk, urgency, stand-by, and shift. Thus, this study divided fire officers'stress factors into job-related factors (risk, urgency, stand-by, alternation) and role-related factors (role conflict, role ambiguity, role overload), and empirically analyzed how these factors affect their job satisfaction. According to the results of this study, fire officers' job characteristics and their roles in the organization had a significant effect on their job satisfaction. Particularly, among the job-related factors, urgency and stand-by had a positive effect on job satisfaction, and among role-related factors, role conflict and role overload had a negative effect on job satisfaction. In addition, fire officers' stress and job satisfaction were significantly different according to their job (fire fighting, rescue and first aid, fire administration, others), and according to their workplace (fire fighting headquarters, fire station, 119 safety center).

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.12
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• pp.117-128
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• 2013

u-safety service system inter-works with the diverse operation agencies, through CCTV network, such as the emergency call terminal with built-in GPS, the mobile communication network, u-safety service provider, relay system and CCTV control center. In the case of the emergency call, this service searches the location of caller in real time, and then continues to search the location of caller through the control of CCTV in the searched place, and can provide the several agencies like guardian, police office, fire station, hospitals, relief organizations and municipalities, with the diverse information necessary for the secure rescue through SMS and wired network. In this paper, a new protocol and specification for u-safety service relay system is designed and implemented. The effectiveness of presented protocol is verified by computer simulation. The designed protocol of u-safety service is applied to real 3GPP and 3GPP2 mobile communication networks to verify its performance.

• Journal of Digital Contents Society
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• v.16 no.1
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• pp.43-51
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• 2015

South Korea decided to use the public safety long term evolution (PS-LTE) method to build a wireless communications network for national disaster. The move will allow all disaster management agencies, including police, firefighters and the military to use multimedia information, including videos, in addition to voice to carry out rescue operations from 2017. The Ministry of Science, ICT and Future Planning said Thursday that it adopted PS-LTE as the technology method for national disaster management system following a national policy coordination meeting last month. PS-LTE is a method integrating group communication, direction communication between terminals and independent base station function with existing LTE technology. Until now, disaster management agencies used technology that only allowed voice communication. However, transmission of multimedia information is possible using PS-LTE.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.257-266
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• 2014

This study has been performed to come up with any rational way for responding to the functions of fire-fighting spaces newly required by the changing social paradigms and to seek for the approach to designing fire-fighting spaces by taking into account the psychological and behavioral factors of fire-fighters who are exposed stress of operations. In particular, it is to satisfy any physical and functional requirements as special working-spaces and to reflect the psychological and behavioral approach to the workers who are forced to be at standby for a long time, which is the characteristic of their operation, to designing. Accordingly, for fundamental appreciation of whether or not such space programs as space organization needed for operational function are being practiced actively, the fire-fighting headquarters of Incheon City has been selected for the research. First, in the process of assessing the trend of organizing the space at safety centers for the recent 20 years, those built more than 20 years ago were left out from the space selection for the research. Second, those with less than 20 operators also were excluded. Third, among those completed in the same year, only one was selected, which was to avoid overlapping, with the consideration its regional representative nature for applying the safety centers in the jurisdiction of the headquarters equally. The study was performed through the visits to and the actual inspections by surveys at the selected 119 Safety Centers as well as the reviews of literature based on case studies. And for the assessment of significance, surveys and analysis of reliability and factors were carried out. The actual users of Safety Centers were picked as objects for the assessment of significance of space factors at 119 Safety Centers, which revealed that there are five types of dimensions for factor-analyzing standard with which users estimate any significance, which are "Area of Mobilization Preparation and Return" "Area of Standby" "Area of Working Activities" "Area of Employ Welfare" and "Area of Support".

• Fashion & Textile Research Journal
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• v.23 no.4
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• pp.515-526
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• 2021

This study aimed to investigate the evaluation of firefighting gloves and the behavior regarding their usage, of firefighting officials in Seoul, using a questionnaire. Responses from a total of 270 firefighters who are responsible for putting out fires or undertaking rescue works in Seoul were analyzed. As per the findings, the firefighters considered ease of hand operation and fire/flame protection as the most important performance factors for firefighting gloves, and they were satisfied with the supply status of the gloves. The average number of firefighting gloves currently owned by the firefighters was 2.6 ± 0.8 pairs. Thirty-nine percent of the respondents said that their firefighting gloves lasted, with maintained performance, for more than six months and less than a year, and when asked how they handled the gloves with degraded performance, 46% of them said that they would discard them. Sixty-eight percent of the respondents said that they used the most recently developed and supplied gloves, which they considered as the most satisfying gloves and which they mainly used these days. Respondents were highly satisfied with the fire/flame protection performance of their firefighting gloves, but were less satisfied, however, with the glove fit. These results suggest that there has been a significant improvement in the overall performance level and supply status of the firefighting gloves. Given the current situation, careful considerations with flexible approaches are needed on the current firefighting gloves size system as well as on the personal protective equipment maintenance and management scheme.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.3
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• pp.487-498
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• 2013

A variety of location-based services applications, such as missing children search, emergency rescue requests and so on that requiring high-precision location information are increasing. Precision of GPS that can be used in most systems, however, is still low. In this paper, we design and propose a low cost differential global positioning system(DGPS) based on Web services using object-oriented modeling technique which can offer useable location service, variety device and safe service in wireless environment. The proposed system is designed with UML based on object-oriented modeling to maximize system recyclability and system scalability. In addition, we would like to improve the precision of the GPS in accordance with mobile station location when build low cost mobile station, location differential framework and server. We implement a communication interface based on web-service which is available in the form of a variety of services and can offer stable according to mobile environments. Finally, as performance evaluation results, we can obtain precision location within 1 ~ 2m through proposed system and 88.5% probability of less than 2m.