• 보존과학회지
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• 제26권4호
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• pp.437-443
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• 2010

화석 연료의 생성물인 유해 부식 가스와 이들의 원인으로 나타나는 산성 강하물이 야외 동(銅) 조형물을 보호하고 있는 왁스에 미치는 환경에 대한 영향성을 연구하였다. 부식이 유해 가스보다는 체류성이 강한 산성 강하물에 의해 급격히 진행되는 것으로 볼 수 있었으며, 이 부식의 시작이 코팅된 왁스의 백화 현상으로부터 시작되는 것을 알 수 있었다. 산성도가 증가할수록 백화 현상이 크게 발생하였으며 결과적으로 산성강하물 및 부식 가스에 의해 백화 현상의 시작으로 내부 금속의 노출 현상이 나타나게 되어 부식이 진행되는 것으로 알 수 있었다. 왁스가 코팅된 동 시편은 유해 부식 가스와 산성비, 0.1 M의 산들에 노출되었으며 이의 결과로 가장 변화가 적고 산성도에 대한 저항성이 큰 왁스로는 황산의 결과를 제외하고는 모든 실험에서 Renaissance wax의 변화가 가장 작은 것으로 나타났다.

• Journal of Radiation Protection and Research
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• 제41권4호
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• pp.402-408
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• 2016

Background: Ascertainment bias are common in epidemiologic studies to assess the association between thyroid cancer risk and living near nuclear power plants because many thyroid cancers are diagnosed by chance through health examination. We surveyed the ultra sonography (USG) examination history and conducted thyroid and breast USG in residents living near nuclear power plants. Materials and Methods: The study population comprised 2,421 residents living near nuclear power plants in Korea. Information on demographic characteristics, including diagnostic examination history, was collected by interview using questionnaires. USG examination was conducted to evaluate the presence of thyroid nodules and breast lesion. Study participants were divided into 3 groups according to the distance of their respective villages from a nuclear power plant. The proportions of USG examination history and prevalence of thyroid nodules and breast lesions were compared between groups. Results and Discussion: Examination histories of thyroid USG were 23.1%, 13.7%, and 10.5% in men and 31.3%, 26.7%, 18.3% in women in the short, intermediate, and long distance groups, respectively. There were significant inverse associations between thyroid USG history and the distance from nuclear power plants (P for trend = 0.001 for men and 0.017 for women). However, there was no association between the distance of villages from nuclear power plants and prevalence of thyroid nodules. Conclusion: Our results suggest that there may be an ascertainment bias in population-based studies examining the harmful effects of NPPs examination and researchers should pay attention to ascertainment bias resulted from differential health examination. Correction for ascertainment bias, active follow-up and examination for all study population to remove differential health examination is needed.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.829-832
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• 2008

1980년대 초반부터 대량 주택 공급과 고층 건축물의 급증으로 주차공간 부족현상이 사회적 문제점으로 지적되어져 왔다. 단적인 예로 서울시의 년간 주차장 개소 통계 연보를 살펴보면 2003년에 206,281 개소인 것이 2006년 237,770 개소로 약 15%의 증가율이 나타났다. 이와같이 매년 많은 주차시설이 확충되고 있는 것에 반하여 주차장 바닥에 사용되어지는 마감 재료의 대부분이 유기계 재료가 시공되어 지고 있다. 그러나 최근 "웰빙적 문화현상"에 따라 유기계 재료의 문제점(환경호르몬 배출, 휘발성유기화합물의 화재 위험 등)이 부각되고 있는 실정이다. 이에 본 연구에서는 작업자 뿐만아니라 사용자의 안전을 고려하여 인체 무해한 친환경 고유동 세라믹 수지 모르타르를 이용한 주차장 바닥 표면 마감재의 재료적 특성 분석 및 물성평가를 통하여 기존 유기계 바닥재의 문제점을 보완하고 새로운 개념의 주차장 바닥 마감재에 대한 현장 적용성을 확인하였다.

• 복식
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• 제61권8호
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• pp.57-72
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• 2011

The purpose of this research is to develop a safe and convenient wearable technology wear for bikers. For this, we studied the current usage of two-wheeled vehicles and have also researched the rate of accidents and its causes. We then used them along with previous studies in terms of visual perception as factors to decide the crucial elements of the riders' apparel. Case studies and the break down for the established prototypes for bikers were practiced as well. Based on this process, a survey was conducted to find out the needs of the bikers in the areas of both apparel and technology and then proceeded to produce the appropriate design and device modules. In the apparel sector, the result of the survey indicated that it was considerable that any digital devices were not shown to sustain a natural visible look. It also was essential that the materials were durable and made for safety and easy movement. In the digital function sector, it was significant that a motion input interface which will be embedded into the wear was needed to avoid any dangerous situations. This would ensure the safety of not only the rider but the surrounding riders as well. Lastly, protecting the rider's skin from any harmful elements was regarded necessary as well. Based on these requirements, a new prototype was created and will be tested if the requirements stated above are all met and will be evaluated according to the effectiveness of its functions.

• 제어로봇시스템학회논문지
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• 제22권12호
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• pp.1011-1020
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• 2016

This paper introduces a tactilely transparent soft glove composed of soft materials and flexible structures. Although it is hard to achieve a high grasping force with conventional grip-assist gloves made from soft material, the proposed glove can exert a high force by using a novel structure. This structure has a triangular shape composed of flexible structural frames, soft fabric, and belts. It can produce grip-assist moment compliantly without harmful force or misalignment with the human fingers. The whole finger part that comes into contact with objects is made of thin and soft fabric in order to facilitate sensation transference. The proposed tactilely transparent soft glove enables the user to manipulate various objects owing to both the softness and high grasping force; it helps lifting heavy weight objects as well as permitting delicate tactile feeling on the palm and fingers. The proposed concept was applied to a two-finger grip-assist device for validation. In addition, the experimental results regarding grasping objects, fingertip force, and grasping force are presented.

• Weed & Turfgrass Science
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• 제5권1호
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• pp.35-41
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• 2016

지렁이 분변토는 골프장이나 경기장에서 경기력 저하와 잔디 관리의 균일성을 떨어트리는 위해요소이다. 본 연구는 골프장에서 지렁이 분변토 감소를 목적으로 화학적 방제제(bifenthrin GR+clothianidin GR, ethoprophos GR, imidacloprid SC, picoxystrobin WG, thiophanate-methyl WP)와 차나무(Camellia oliefera) 추출물의 효과를 골프장에서 조사하였다. 모든 처리에서 지렁이 분변토 수가 감소하였으며 thiophanate-methyl WP의 지렁이 분변토 발생 억제효과가 가장 높았다. 차나무 추출물 처리도 지렁이 분변토 발생 효과를 보였는데 펠렛형 차나무 종자추출 부산물과 차나무 추출물 액상제형이 차나무 추출물 입상제형에 비하여 효과가 높았으며, 차나무 추출물이나 부산물 처리가 분변토 관리의 대안이 될 수 있을 것으로 판단된다.

• 한국초전도ㆍ저온공학회논문지
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• 제20권2호
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• pp.1-5
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• 2018

Arsenic (As) is one of the elements having most harmful impact on the human health. Arsenic is a known carcinogen and arsenic contamination of drinking water is affecting on humans in many regions of the world. Adsorption has been proved most preferable technique for the removal of arsenic. Many researchers have studied various types of solid materials as arsenic adsorbent, and iron oxide and its modified forms are considered as the most effective adsorbent in terms of adsorption capacity, recovery, and economics. However, most of all iron oxides have small surface area in comparing with common adsorbents in environmental application such as activated carbon but the activated carbon has weak sorption affinity for arsenic. We have used an activated carbon as base adsorbent and iron oxide coating on the activated carbon as high affinity sorption sites and giving magnetic attraction ability. In this study, adsorption properties of arsenic and magnetic separation efficiency of the magnetized activated carbon (MAC) were evaluated with variable iron oxide content. As the iron oxide content of the MAC increased, adsorption capacity has also gradually increased up to a point where clogging by iron oxide in the pore of activated carbon compensate the increased sorption capacity. The increase of iron oxide content of the MAC also affected magnetic properties, which resulted in greater magnetic separation efficiency. Current results show that magnetically modified common adsorbent can be an efficiency improved adsorbent and a feasible environmental process if it is combined with the magnetic separation.

• 대한족부족관절학회지
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• 제5권1호
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• pp.62-68
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• 2001

Purpose: to investigate the etiology and the results of surgical treatment of the symptomatic accessory navicular in adults. Materials and Methods: Between 1996 and 2000, 17 cases in 16 adult patients who were older than 20 years were diagnosed as painful accessory na vicular. 11 patients could recall a twisting injury of the ankle, and 8 of them were inversion sprain. 4 patients had tibialis posterior tendon lesions. 13 feet of 12 patients were treated by resection of accessory navicular, the synchondrosis, the medial portion of the navicular and reattachment of tibialis posterior tendon without transposition. 9 feet in 8 patients were followed for more than one year after surgery. In 4 patients with tibialis posterior tendon lesions, additional procedures were performed according to the state of the lesion. Results: All were type II accessory navicular bone which had synchondroses. There was gross motion of the synchondrosis in 'the operating field in all feet. Of the 9 feet which were followed for more than one year after surgery, results were excellent in five and good in four. Conclusion: The painful accessory navicular in adult might be closely associated with inversion ankle sprain, and also with the tibialis posterior tendon lesions. Satisfactory result could be obtained without transposition of the tibialis posterior tendon to the undersurface of the navicular and immediate postoperative weight bearing does not have harmful effect on the result.

• 한국주조공학회지
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• 제22권3호
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• pp.121-129
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• 2002

According to the investigation of waste $CO_2$ molding sand in the 15 steel foundries in Busan and Gyeong area, about 1 ton of waste $CO_2$ molding sand per ton of steel castings production was produced In order to reduce amount of $Na_2O$, Loss of Boiling (L.O.B), Loss of Ignition (L.O.I), Conductivity and PH which are present in the waste $CO_2$ molding sand below the reclamation effect, more than 50% of elimination for reclamation was required. It was found that the waste $CO_2$ molding sand does not contain a harmful component designated by industrial waste materials. Reclamation of the waste $CO_2$ molding sand was practically achieved by an abrasive-dry reclamation process. According to bench time of the sodium silicate-bonded $CO_2$ molding sand, reduction of compressive strength and surface stability index(S.S.I) become slowdown. Therefore, the reclaimed sand could be allowed the reuse of molding sand in $CO_2$ molding process including core sand.

• 한국식품과학회지
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• 제50권3호
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• pp.249-259
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• 2018

Radiation technology (RT) has long been applied in various fields for increasing the safety and shelf-life of foods by controlling pathogen-induced poisoning. RT was introduced for the first time in Korea in the 1950s to eliminate harmful microorganisms in food materials. In the 1980s, RT had been scientifically proven to be effective for the sterilization of food and public health products. In recent years, irradiation with gamma rays has also been used for improving physiological properties through the structural modification of natural molecules, which has been proposed to be applicable to various industries. In particular, radiation transformation technology (RTT), which involves the development of new functional compounds through the molecular conversion of natural biomaterials, is becoming a new high-value technology as a fusion technique of RT and biotechnology. The present reports have suggested that RTT can be an effective tool for the development of new functional compounds and improvement of the physiological activity of biomolecules.