• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2545-2552
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• 2018

$SF_6$ has been widely used in high voltage power equipment, such as gas insulated switchgear (GIS) and gas insulated transmission line (GIL), because of its excellent insulation and arc extinguishing performance. However, $SF_6$ faces two environmental problems: greenhouse effect and high liquefaction temperature. Therefore, to find the $SF_6$ substitute gases has become a research hotspot in recent years. In this paper, the liquefaction characteristics of $SF_6$ substitute gases were studied. Peng-Robinson equation of state with the van der Waals mixing rule (PR-vdW model) was used to calculate the dew point temperature of the binary gas mixtures, with $SF_6$, $C_3F_8$, $c-C_4F_8$, $CF_3I$ or $C_4F_7N$ as the insulating gas and $N_2$ or $CO_2$ as the buffer gas. The sequence of the dew point temperatures of the binary gas mixtures under the same pressure and composition ratio was obtained. $SF_6/N_2$ < $SF_6/CO_2$ < $C_3F_8/N_2$ < $C_3F_8/CO_2$ < $CF_3I/N_2$ < $CF_3I/CO_2$ < $c-C_4F_8/N_2$ < $C_4F_7N/N_2$ < $c-C_4F_8/CO_2$ < $C_4F_7N/CO_2$. $SF_6/N_2$ gas mixture showed the best temperature adaptability and $C_4F_7N/CO_2$ gas mixture showed the worst temperature adaptability. Furthermore, the dew point temperatures of the $SF_6$ substitute gases at different pressures and the upper limits of the insulating gas mole fraction at $-30^{\circ}C$, $-20^{\circ}C$ and $-10^{\circ}C$ were obtained. The results would supply sufficient data support for GIS/GIL operators and researchers.

• Journal of Preventive Medicine and Public Health
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• v.43 no.6
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• pp.535-542
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• 2010

Objectives: Exposure assessment is a major challenge faced by studies that evaluate the association between pesticide exposure and adverse health outcomes. The objective of this study was to investigate the reliability of information that farmers self-report regarding their pesticide use. Methods: Twenty five items based upon existing questionnaires were designed to focus on pesticide exposure. In 2009, a selfadministrated survey was conducted on two occasions four weeks apart among 205 farmers residing in Gyeonggi and Gangwon provinces. For a reliability measure, we calculated the percentage agreement, the kappa statistics and the intraclass correlation coefficient (ICC) between the two reports according to the characteristics of the subjects. Results: Agreement for ever-never use of any pesticide was 96.4% (kappa 0.61). For both 'years used' and 'age at the first use' of overall pesticides, high agreement was obtained (ICC: 0.88 and, 0.78, respectively), whereas those of 'days used' and 'hours used' were relatively low (ICC: 0.42 and, 0.66, respectively). The kappa value for the use of personal protective equipment ranged from 0.46 to 0.59, and hygiene activities came out at 0.19 to 0.37. The agreement for individual pesticide use ranged widely and there was relatively low agreement due to the low response rates. The reliability scores did not significantly vary according to gender, age, the education level, the types of crop or the years of farming. Conclusions: Our results support that carefully designed, self-reported information on ever-never pesticide use among farmers is reliable. However, the reliability of data on individual pesticide exposure may be unstable due to low response rates and needs to be refined.

• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.232-243
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• 2018

The construction, development and maintenance of an economically, environmentally and socially sustainable campus involves the integration of measuring tools and technical information that invites and encourages the community to know the actual state to generate positive actions for reducing the negative impacts over the local environment. At the Universidad Nacional de Colombia - Campus $Bogot{\acute{a}}$, a public area with daily traffic of more than 25000 people, the Environmental Management Bureau has committed with the monitoring of the noise pollution and air quality, as support to the campaigns aiming to reduce the pollutant emissions associated to the student's activities and campus operation. The target of this study is based in the implementation of mobile air quality and sonometry monitoring equipment, the mapping of the actual air quality and noise pollution inside the university campus as a novel methodology for a sub-area inside a megacity. This results and mapping are proposed as planning tool for the institution administrative sections. A mobile Kunak$^{(R)}$ Air & OPC air monitoring station with the capability to measure particulate matter $PM_{10}$, $PM_{2.5}$, Ozone ($O_3$), Sulfur Oxide ($SO_2$), Carbon Monoxide (CO) and Nitrogen Oxide ($NO_2$) as well as Temperature, Relative Humidity and Latitude and Longitude coordinates for the data georeferenciation; and a sonometer Cirrus$^{(R)}$ 162B Class 2 were used to perform the measurements. The measurements took place in conditions of academic activity and without it, with the aim of identify the impacts generated by the campus operation. Using the free code geographical information software QGIS$^{(R)}$ 2.18, the maps of each variable measured were developed, and the impacts generated by the operation of the campus were identified qualitative and quantitively. For the measured variables, an increase of around 21% for the $L_{Aeq}$ noise level and around 80% to 90% for air pollution were detected during the operation period.

• 대한공업교육학회지
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• v.36 no.2
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• pp.239-256
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• 2011

The purpose of this study is to deduce the effective improvement plans of engineering education system and to provide the base materials by analyzing satisfaction and problems in the perception survey of stakeholders related in engineering education system including Engineering Education Accreditation System. Engineering education system improvement plans from the results of study are as follows. First, government and university should provide more financial support to the college in order to improve education environment such as laboratories and equipment. Second, in order to improve links among engineering education stakeholders, student-professor, student-faculty, and colleges should operate effective mentoring program and consultation plan. Third, according to service quality evaluation, colleges need to give rewards to distinguished faculties for their outstanding work and build up job training about services in order to enhance satisfaction of students and professors, Also, business related to Engineering Education Accreditation System should be simplified and needs to increase the number of workers exclusively responsible for this work. Forth, in order to enhance comprehension of learning outcome and outcome of Engineering Education Accreditation System, it is necessary to improve Engineering education innovation center's status, to establish active systematic promotion system and to operate engineering education evaluation expert committee such as 'Engineering education system evaluation council'. Fifth, because of the stakeholder's shortage of benefits and tiredness accumulation, the issue of effectiveness in engineering education institutions has raised controversy. Thus, engineering education institutions needs to take measure necessary. Moreover, engineering education improvements should be improved by reflecting opinions from professors, faculties and students who are practically planning, operating and participating engineering education programs.

• Asian Oncology Nursing
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• v.4 no.2
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• pp.124-134
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• 2004

The major results of this study were as follows : 1. The percentage of nurses who know the complementary and alternative therapies was 50.1% Most of them(70.6%) acknowledged the therapies from newspapers, television and magazines. 2. The complementary and alternative therapy was perceived as effective by 64.9% of the nurses and as trusted by 60.2% of them The effective methods of the therapy are acupuncture herb medicine and massage. 3. Most of the nurses 93.4% experienced getting inquiries from patients or their guardians whether to use the therapies. 4. The complementary and alternative therapies was experienced by 38.9% of nurses and 7.1% of them use the therapies frequently 92.9% of patients and families were satisfied with the result 'Massage Therapy' was used the most with no side-effects and thus higher need of education for nurses. 5. They wanted to be trained for massage therapy finger-pressure, music therapy, acupuncture, aroma therapy in order. 6. Reliance on the complementary and alternative therapies, 75.2% of nurses completed the course trusted the therapies and the result of others uncompleted was similar as 52.2% Moreover both 79.5% of nurses completed it and 61.6% of the others said that the complementary and alternative therapy's nursing interventions is possible to develop. 7. It shows high relation to recognition having possibilities for applying and developing as the nursing intervention. if the confidence is as high as about the complementary and alternative therapies. Based of the results of this study as above this study proposes as follows. First, The nurses should understand mentality of the patients so that the nurses have to put in operation appropriate nursing intervention as accurate knowledge of the alternation therapies using to cancer patients for having on damages to patients from their rash using way. Furthermore, it is necessary to supply the special place and the professional nurses taking complete charge at them. Next politic interest and support from government are required to develop and practice systematic and resonable education programs for the complementary and alternative therapies. Moreover, it is necessary for nurses to be educated about the therapies continually. Finally, it is compulsory that the research and development for complementary and alternative therapies is needed. In addition, it has to be made standard and legal equipment for safety efficacy and theory about the therapies.

• The Journal of Industrial Distribution & Business
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• v.10 no.5
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• pp.27-36
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• 2019

Purpose - Naver has emerged as a new leader in the open market. While existing open markets such as Gmarket, 11th Street, and so on are suffering from profitability deterioration, Naver is attracting sellers based on low commission and powerful search engine. We would like to analyze the impact of Naver shopping on the national economy, especially on employment, in a situation where the market reaction to Naver's strength as a leader in online shopping is mixed. Research Design, Data, and Methodology - Through the demand inducing inter-industry analysis, we estimate the employment inducement effect by Naver shopping from its shopping transaction. In turn, through the supply inducing inter-industry analysis, we estimate the employment inducement effect by Naver shopping from its low commission and powerful search engine. For the purpose of inter-industry analysis, as of 2018, the most recently announced 2014 inter-industry table (extension table) from the Bank of Korea is used. Results - The results of this study are as follows. First, Naver Shopping is expected to generate 7.8 trillion won's trade in 2018, resulting in 244,225 of job inducement, and 158,598 of employment inducement. In addition, Naver Shopping is estimated to benefit KRW 213 billion to its sellers due to low commission and powerful search function, resulting in 8,667 of job inducement, and 5,655 of employment inducement. Second, in terms of job inducement and employment inducement due to Naver Shopping's trade, transportation, business support service, information and communication, broadcasting, restaurants and lodging were ranked. Third, in terms of job inducement and employment inducement due to Naver Shopping's low commission and powerful search function, restaurants and hospitality, f/b and cigarette manufacturing, construction, and transportation equipment manufacturing were ranked. Conclusions - The number of job inducement resulting from low commission and powerful search engine of Naver shopping in 2018 was 8,667 (3.7% of 244,225, which was caused by transaction in Naver shopping in 2018), and employment inducement was 5,655 (3.7% of 158,598, which was caused by transaction in Naver shopping in 2018), which can be considered as additional employment impacts of Naver Shopping compared to the other online shopping operators.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.31-43
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• 2017

This study was aimed at analyzing the operational efficiency of DPAs(the delivery and pickup agents), which serve as sub-terminals in parcel delivery services, using CCR/BCC models in DEA. The input variables included the number of employees, and the amount of equipment and the operating expenses. The output variable was revenue value. The efficiency for the period from 2014 to 2016 was analyzed. The results revealed that the operational efficiency improved in 2016, compared with 2014, in both CCR and BCC models. According to the benchmarking analysis, DMU 1 and DMU 7 showed higher efficiency in 2016. The inefficiency analysis based on the BCC model showed increased efficiency of all factors in 2016 when compared with 2014. The Malmquist productivity index (MPI) dropped slightly as a result of technical changes and indicated a declining technical efficiency in all DMUs. This study suggests the need for government-led systematic improvement and support for DPAs by providing current insight into the parcel delivery industry and analyzing DPAs' operational efficiency in Korea for the first time. This research performed efficiency analysis of DPAs located in new town of paju and gimpo cities. In future research, comparative study on efficiency analysis including new town, old town area, and other cities are needed.

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.106-115
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• 2010

Recently, as the size of construction projects are getting bigger and higher, more effective managing methods are required in management areas such as duration reduction, cost reduction and quality management. In the current construction industry, conjunction with IT(Information Technology) is being noticed as a solution to support these needs. Various IT solutions such as Bar Code, Personal digital assistant(PDA), global positioning system(GPS), radio frequency identification(RFID) are being developed. In this research, among the various IT solutions, the Real Time Locating System(RTLS) which is acknowledged as a technology with high applicational potential is analyzed. Based on this analysis, a locating system to apply in construction sites is developed and validated. The locating system is developed to prevent construction disasters through real-time management of workers and equipment, which enables effective application in the area of construction safety management. Moreover, applications of the locating system in many different areas like construction material realtime monitoring, construction automation, construction quality management, maintenance management are expected.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.108-117
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• 2016

In this paper, a portal system compatible with MRV regulation was designed to monitoring, reporting and verifying $CO_2$ emission and fuel consumption data from an international ship. A portal system supports monitoring and reporting task of international shipping companies and calculates national greenhouse gas inventory. EU MRV law, MRV discussions of IMO, responses of international shipping companies to ship energy efficiency and greenhouse gas regulation, and greenhouse gas statistics on international shipping were analyzed to drive portal system requirements. For ship energy efficiency and $CO_2$ emitted monitoring, a data collection module was designed based on on-board equipment, energy efficiency measuring device and navigation report. Data transfer module with easy management and minimized usage to transfer ship data to shore was designed. A portal system was designed to convert the collected data into the standard reporting format, perform monitoring, statical analysis, verification and auto report generation, and support national greenhouse gas inventory.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.175-183
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• 2020

This study suggests a solution regarding the effects of apartment facility maintenance and fire safety facility maintenance on the residential satisfaction of residents. The results are as follows. Firstly, facility maintenance had a negative effect on residential satisfaction. Analysis revealed that residential satisfaction decreased the more breakdowns there were in the facilities. This revealed that when maintenance staff neglect the residents' complaints due to the repetitive aspect of their jobs, there was a negative effect on residential satisfaction; therefore, residential satisfaction must be increased by maintaining the facilities well and training support for maintenance staff. Secondly, fire safety facilities had a negative effect on residential satisfaction. Analysis revealed that residential satisfaction decreased the more malfunctions there were in the fire safety facilities and the more replacements there were in fire fighting equipment. This revealed the importance of safety and the fact that the apartment heavily relies on fire safety facilities because there may be a low awareness regarding safety; therefore, maintenance staff must lower the damage from fire safety facilities and to increase the residential satisafaction of residents. Lastly, there needs to be repetitive training and education for residents regarding fire fighting and evacuating in accordance with the fire fighting plan as a means to strengthen residents' safety awareness.