• 한국자동차공학회논문집
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• 제25권1호
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• pp.51-59
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• 2017

In 2014, there were approximately 4,762 fatalities on Korean roads. The fatality rate has decreased by 6.5 %, as compared to that of the previous year. The pedestrian-vehicle fatalities (1,795) have also decreased by 6 % over the previous year. However, the percentage of the pedestrian fatalities has increased from 37.9 % to 38.7 % during the same period. This is why further research is required, even though the KNCAP pedestrian safety assessment and KMVSS for pedestrian protection currently exist. This paper studied the Upper Legform to Bonnet Leading Edge Test at the front of the vehicles, which has not been introduced yet in Korea. The test method and procedure of the new BLE test in the Euro NCAP test protocol have been reviewed, and the physical tests on SUV and sedan with different bonnet leading edge heights have also been conducted and reviewed. In addition, the test results and characteristics have been analyzed via comparison with the former BLE test and each vehicle type.

• 한국대기환경학회지
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• 제29권6호
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• pp.745-756
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• 2013

The purpose of this study is to evaluate representativeness of fuel-based emission factors. Twelve light-duty diesel vehicles which meet Euro-3 to 5 legislative emission limits were selected for emission tests. Second-by-second modal emission rates of vehicles were measured on a standard laboratory chassis dynamometer system. An off-cycle driving cycle was developed as a representative Korean real-world on-road driving cycle. Fuel-based emission factors were developed for short trip segments that involved in the selected driving cycle. Each segment was defined to have unit travel distance, which is 1 km, and characterized by its average speed and Relative Positive Acceleration (RPA). Fuel-based $NO_x$ emission factors demonstrate relatively good representativeness in terms of vehicle operation conditions. $NO_x$ emission factors are estimated to be within ${\pm}20%$ of area-wide emission factor under more than 40% of total driving situations. This result implies that the fuel-based $NO_x$ emission factor could be practically implemented into the on-road emission management strategies, such as a remote sensing device (RSD). High emitting vehicles as well as high emitting operating conditions heavily affect on the mean values and distributions of CO and THC emission factors. Few high emitting conditions are pulling up the mean value and biasing the distributions, which weaken representativeness of fuel-based CO and THC emission factors.

• Tribology and Lubricants
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• 제25권6호
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• pp.387-398
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• 2009

The operation condition of recently designed pistons for high power and high speed diesel engine become more severe due to the increment of combustion pressure and temperature. So, in order to overcome high temperature, the application of the mono-metal cast aluminum alloy piston featuring an enclosed cast-in open cooling gallery has increased. In this research, it is developed a PCJ (piston cooling jet) rig tester, described the test procedure and validated the performance of sample piston cooling gallery design. Then the test rig will be used for developing the design technology of piston cooling gallery. The test rig is composed with oil reservoir and pumping system, oil jet system, piston fixing and moving system, collecting oil measuring system, and data measuring and recording system. It will be measured collecting efficiencies under conditions of a few piston positions, oil jet pressures and oil viscosities for a piston cooling gallery. Furthermore, the PCJ rig tester will be used for the optimum design of the oil cooling gallery which being applied to increase the cooling efficiency of pistons in diesel engines satisfying the EURO V emission regulation and the more.

• 디지털융복합연구
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• 제12권6호
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• pp.559-568
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• 2014

오늘날과 같은 다매체 시대에서는 미디어의 형태(하드웨어)보다 미디어의 내용(콘텐츠)이 성패를 좌우한다고 해도 과언이 아닐 정도로 콘텐츠가 중요한 요소로 작용한다. 인기 있는 텔레비전 프로그램들은 국경을 넘어 공급되고 현지 시청자들에 맞게 각색된 이른바 '포맷'이라는 형태로 확산되고 있다. 이러한 포맷산업은 미국에서 시작되었지만 1990년대부터 유럽으로 주도권이 옮겨지게 되었고, 이후 "super-formats"에 의해 확고하게 자리잡은 산업이며 오늘날 연간 31억 유로로 추정되는 가치를 지니고 있다. 특히 2000년대 이후 세게 방송포맷산업의 중심지로 떠오른 영국의 사례는 문화콘텐츠산업을 육성하고자 하는 한국에 시사하는 바가 크다고 할 수 있다. 본 연구는 이러한 방송포맷산업의 역사를 연대기적으로 고찰하고 콘텐츠 강국으로서의 영국이 가진 산업적 배경을 살펴봄으로써 한국의 콘텐츠산업에 시사하는 바를 찾고자 함에 그 목적이 있다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제19권3호
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• pp.156-161
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• 2008

Objectives: The purpose of this study was to investigate the prevalence of sleep problems in Korean elementary school children and the differences in sleep problems elated to their school grade and gender. Methods : One public elementary school in Dae-gu, Korea as randomly selected. And, parents who agreed to participate this study were asked to complete a modified version of Tucson Children's Assessment of Sleep Apnea screening questionnaire (TuCASA). Results: The most common sleep problem was 'falling asleep in vehicle (44.2%)' and the prevalence rate of this problem differed by school grade. The prevalence rate of falling asleep while watching TV before 8 P.M. (8.0%), daytime fatigue (21.9%) and nocturnal enuresis during the past 6 months (5.3%) were significantly differed by school grade. The prevalence rate of falling asleep while doing home work, falling sleep during a lesson, snoring and bruxism were 12.6%, 1.0%, 26.7% and 13.2% respectively. Although these rates did not show any differences between grades, snoring as more in boys and daytime fatigue was more in girls. Conclusion: This study demonstrates that many elementary school children may have various sleep problems. Lower grade elementary schoolers had sleep problems which related to euro-developmental factors, whereas higher grade elementary schoolers had sleep problems related to sleep deprivation and stress. Finally, more female schooler showed signs of fatigue or sleepiness than male schoolers.

• Journal of Preventive Medicine and Public Health
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• 제37권4호
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• pp.353-358
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• 2004

Objective : To determine the quality of life and cost consequences for deaf adults who received a cochlear implant. Methods : The data from 11 patients, post-lingual deaf adults who received cochlear implants from 1990 to 2002, underwent cost-utility analysis. The average age of the participants was 49.6 years. The main outcomes were direct cost per quality-adjusted life-year (QALY) using the visual analog scale (VAS), health utility index (HUI), EuroQol (EQ-5D), and quality well-being (QWB), with costs and utilities being discounted 3% annually. Results : Recipients had an average of 5.6 years of implant use. Mean VAS scores increased by 0.33, from 0.27 before implantation to 0.60 at survey. HUI scores increased by 0.36, from 0.29 to 0.65, EQ-5D scores increased by 0.26, from 0.52 to 0.78, and QWB scores increased by 0.16, from 0.45 to 0.61. Discounted direct costs were $22,320, yielding $19,223/QALY using VAS, $17,387/QALY using HUI, $24,604/QALY using EQ-5D, and $40,474/QALY using QWB. Cost-utility ratios using VAS, HUI, and EQ-5D were all below $25,000 per QALY, except using QWB. Conclusion : Cochlear implants in post-lingual deaf adult have a positive effect on quality of life at reasonable direct costs and appear to produce a net saving to society.

• 동의생리병리학회지
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• 제31권4호
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• pp.238-245
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• 2017

This retrospective observational study was aimed to evaluate that Daoyin Exercise therapy improves the symptoms related to lumbar disc herniation. We analyzed the medical records of 7 patients, who satisfied with inclusion and exclusion criteria. The subjects of the study were the patients who were prescribed Daoyin Exercise Therapy and Korean medical treatments for lumbar intervertebral disc herniation at Dunsan Korean Medicine Hospital of Daejeon University from July 25th, 2016 to March 31th, 2017. The effects of Daoyin Exercise Therapy was evaluated by comparing before and after taking Daoyin Exercise Therapy through 0-10 Numeric Rating Scale(NRS), Roland & Morris Disability Questionnaire(RMDQ), Trunk Extension Flexion(TEF) Program, EuroQol five Demension Questionnaire(EQ-5D, EQVAS) of the symptoms including lower back pain. The Daoyin Exercise Therapy combined with Korean medicine treatment reduced NRS($3.357{\pm}3.038$) and RMDQ($9.50{\pm}6.364$), and improved Muscle endurance($44.429{\pm}45.136$), EQ-5D($0.09{\pm}0.12$) and EQVAS($6.571{\pm}19.260$) of the 7 patients without side effects. These results implied that Daoyin Exercise Therapy might helps to improve symptoms of patients with lumbar disc herniation by reducing the symptoms of lower back pain and improving muscle endurance, quality of life, strength enhancement and core muscles.

• 한국구조물진단유지관리공학회 논문집
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• 제17권6호
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• pp.77-87
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• 2013

국내 교량 설계에서 온도 하중에 대한 현재 LSD (한계 상태 설계법)는 다양한 교량 형식에 대한 동일한 기준을 적용하고 있다. 본 연구에서는 유효 온도를 산정하기 위해 실제 크기의 상판이 없는 강상자형거더교 시험체를 제작하였다. 1년동안 강상자형거더교모형의 18개 지점에서 온도데이터를 측정하였다. 측정된 데이터를 바탕으로 대기 온도에 따른 교량단면내 유효 온도를 산정 하였다. 유로 코드의 유효 온도와 비교할 때 실측 유효온도의 결과는 매우 유사한 상관 관계를 보였다. 따라서, 본 데이터를 기반으로 산정 된 유효 온도는 국내 교량 설계에 온도 하중에 적합한 설계 기준을 제시하기 위한 기초 자료로 사용할 수 있다.

• 한국가스학회지
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• 제15권2호
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• pp.15-20
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• 2011

도심 대기오염을 줄이고자 도입된 CNG 버스는 현재의 배기규제 기준을 만족시켜 도시 대기환경 개선에 많은 기여를 했지만 추가적인 후처리 장치의 도움 없이는 차기 배기기준인 유로6 배기규제를 만족시키기 매우 어렵다. 수소는 매우 활발하고 빠른 반응성을 가지고 있으며 희박가연한계 또한 매우 넓어 기존 연료와 함께 사용 시 개선된 연소 및 배기성능을 기대할 수 있다. 따라서 본 연구에서는 시내버스용 대형 CNG 엔진에 수소를 일정 부분 CNG와 혼합한 HCNG 연료를 공급하여 희박연소를 시킴으로서 연소 및 배기성능을 개선하는 실험을 수행하였다. 수소혼합비율, 공연비, 점화시기 변화에 따른 연소 및 배기성능을 살펴보고 최적운전조건을 찾아내었으며 산화촉매 성능평가를 통해 11리터 버스용 HCNG 엔진의 상용화 가능성을 검토하였다.

• 한국항행학회논문지
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• 제25권6호
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• pp.498-509
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• 2021

선행 항공기의 날개 끝단에서 발생하는 후류 요란으로 인해 후행 항공기는 정상적인 운항에 영향을 받을 수 있다. 현재는 항공기 최대이륙중량에 따라 4개의 카테고리로 분류하여, 기준 거리별 항공기 수평 분리를 적용하고 있다. FAA 및 EURO-CONTROL을 중심으로 항공기 후류 요란의 크기와 영향이 기존의 거리 분리치보다 더 작다는 것이 연구되었고, 이것을 바탕으로 분리 기준을 7개의 카테고리로 세분화한 규정(RECAT)이 제시되었다. 본 연구에서는 ICAO Doc. 10122의 초안을 이용하여 국내 공항의 RECAT 도입 필요 여부를 확인하고, 활주로 절대 수용량 계산 방법의 하나인 Harris 모델을 이용하여 인천국제공항의 절대 수용량을 산출하였다. 분석 결과 RECAT 도입에 따라 활주로 절대 수용량의 증가가 가능할 것으로 확인되었으며, 계산된 결과 및 계산에 활용한 방법은 국내 공항의 RECAT 도입 검토에 기본 자료로 활용될 수 있을 것이다.