• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.643-646
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• 2009

This study was conducted to simulate the influence of vibration associated with cycling on the body. In this simulation the human model that the riding on a bicycle which have suspension and non-suspension front forks was used. And to arouse impact two kind of bump, 50mm height of radical raised spot and 150mm height of slow raised spot, were used. The vertical displacement of head, the vertical acceleration of head and the torque of neck joint were analysed. The results say that the function of shock absorbing was grater when passing though a 50mm height of radical raised spot then a 150mm height of slow raised spot.

• 콘크리트학회논문집
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• 제28권1호
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• pp.3-11
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• 2016

건물의 자중을 저감시킴으로서 시공성을 향상시키기 위한 방안으로 중공 PC슬래브에 대한 관심이 높아지고 있다. 이와 같은 측면에서, 최근 새로운 형태의 부분 PC 슬래브 시스템인 Tripple Ribs Slab (TRS)가 개발되었다. TRS부재는 3개의 리브와 스트랜드로 프리스트레싱된 바닥구조로 구성되어 있다. TRS 바닥구조는 웨브와 웨브 사이에 스티로폼(styrofoam)을 채운 뒤 토핑 콘크리트를 타설함으로서 슬래브 시스템을 구축한다. 본 연구에서는 TRS의 휨성능을 검토하기 위해 휨실험을 진행하였다. Full scale로 제작된 5개의 실험체를 제작한 뒤 휨파괴되도록 단순지지조건으로 실험하였으며 실험결과 강도를 기준 식들과 비교하였다. 실험에서의 변수는 부재의 깊이와 토핑 또는 슬립포밍시 형성되는 추가의 콘크리트 턱의 유무이다. 또한 실험체들에 대하여 비선형 단면해석을 실시하였으며 그 결과를 실험결과와 비교하였다. 실험으로부터, TRS는 설계하중을 충분히 지지할 수 있는 휨성능과 연성능력을 가지고 있으며 실험체의 강도는 기준 식으로 적절하게 예측될 수 있는 것으로 나타났다. 추가의 턱은 실험체의 강도에 영향을 미치지 못하는 것으로 나타났으며 이에 따라 이들 턱은 굳이 추가의 작업을 통하여 제거할 필요는 없는 것으로 사료된다. 비선형 단면해석을 통하여 TRS의 휨거동을 보다 정확하게 예측하기 위해서는 슬립포밍에 의한 콘크리트의 취성적인 특성을 해석에서 고려할 필요가 있는 것으로 판단된다.

• 한국식품영양학회지
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• 제2권1호
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• pp.61-72
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• 1989

This study was conducted to gather the baseline data on realities of experimental-practice and opinions toward spot-practice, and to examine how to cope with the problems raised at the Department of Food and Nutrition of Junior Technical College in Korea. Questionnaires were gathered from 42 chairmans of the Department of Food and Nutrition and 140 Present dieticians worked in Seoul, Bucheon am Seongnam area. The results are as follows, First, as a whole, each college had 2~3 experimental laboratory (Lab), in which Cooking Science Lab. Chemistry Lab and Microbiology Lab were occurred at higher frequency as Lab's name. Second, the numbers per experimental-practice class were more than 40 at most colleges. 85% of Present dieticians have answered to feel too much numbers per the class during their college days, whereas professors' opinions toward the numbers per class were suitable at 20~30 persons per class. Third, professors' opinion toward the adquate ratio of the theory subject classes to experimental subject classes was suitable at 60 : 40. Dieticians answered to take the theory subject classes partly or mostly on behalf of the experimental-practice classes. Fourth, the main reasons which inhibited normal experimental-practice class were the class for emphasis on examination, the shortage of experiment budget, the excess of class members, the shortage of experimental Lab Also, this results showed same propensity to present dieticians' opinion toward the same question above. Fifth, among the experimenta1-practice subjects established at the Department of Food and Nutrition, Diet Therapy Lab was highest frequency class emphasized on theory followed by Nutrition Counselling Lab, Food Processing and Storage Lab, Food Hygiene Lab and Food Microbiology Lab in that order. Here, Basic Chemistry Lab, Biochemistry Lab, Food Microbiology Lab were pointed as subjects far from the present task of dieticians. Sixth, Department of Food and Nutrition, as a whole, has conferred with spot-practice arrangement About 50% (all who want to join spot-practice) of second year students took part in spot-practice. In the other way, all colleges except for 2 colleges didn't give the credit for the spot-practice system. Seventh, according to the on analysis on spot-practice places, manufacturing company was at highest frequcney followed by hospitals, elementary school having group feeding system in that order. Especially, 16.7% (5 colleges) of the total colleges sent the students to the research institute related to food industry for spot-practice experience. Eighth, Professors' opinions toward the spot-practice time and period were preferable on summer vacation of second year and for 1~2 weeks, respectively. On the contrary, 74 dieticians answered to the adquate period as for 4 weeks. Ninth, 86 dieticians of the total 140 answered to complete the spot-practice during their college days, which helps the present task of them. Lacks of spot-practice program, Lacks of comprehension of upper personals and lacks of group feeding equipments ranks higher as difficulties in spot-practice management.

• 대한안전경영과학회지
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• 제23권3호
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• pp.97-102
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• 2021

This study developed a scenario to understand the reaction rate and operational time according to RTI value of rate of rise detector in each type in case of fire mattress. In the results of analyzing the reaction rate and operational time of detector in each scenario, in case when installing a single detector, the elevated temperature per minute was raised to 8℃/min ~ 9℃/min. In case when installing two detectors, it was raised to 9℃/min ~ 10℃/min. In case when installing three detectors, it was raised to 10℃/min. The horizontal distance between detector and mattress was 1.8m~2.5m. Whenever the number of detectors was increased, the horizontal distance was decreased. The operational time of detector was within maximum 540 seconds and minimum 420 seconds. As the research tasks in the future, there should be the researches on the effects of reaction rate of detector on the evacuation in case of fire through the result value of RSET by setting up the latency until the detector operates, and the researches on the safety by understanding if the operational time of detector is suitable for the evaluation standard of performance-centered design.

• 한국환경복원기술학회지
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• 제10권6호
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• pp.139-151
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• 2007

To protect the surface of ground-cutting slopes and ground-raised slopes and to recover environment-friendly slopes at the national road expansion construction between Gamchon and Yaechon, test-construction work was done using several modes of hydro-seeding measures to select a suitable construction method through the field survey; the results were as follows : As a result of survey on physio-chemical characteristics of soil, the average soil inclination on ground-raised slopes was from 4.73 mm to 5.37 mm; the average soil acidity was from pH 6.47 to 6.73; the average soil humidity was within the scope of 0.57~1.70 %,; the average soil inclination on ground-cutting slopes was 9.17~10.43mm; the average soil acidity was pH 6.67~6.77 and the average soil humidity was within the scope of 0.53~1.27 %; considered overall, they showed generally satisfactory base materials for plant breeding. As a result of the number of sprouting individuals, the average sprouting number of individuals on test spots executed by Coir net with Seed spray construction methods and the average number of sprouting individuals on other test spots executed by furrow-digging with Seed spray and Straw mat-mulching measures were 1,172 number of per square meter and 970 number of per square meter respectively; thus they showed higher numerical value comparing with other test spots. Likewise, the average number of sprouting individuals on test spots of the ground-cutting slopes executed by Coir net with Seed spray method and the average number of sprouting individuals on other test spot executed by furrow-digger with Seed spray and Straw mat-mulching measures were found to be 1,107 number of per square meter and 1,105 number of per square meter respectively, whose numerical value showed rather higher other test spots. As a result of a survey on living plants' breeding index [dried weight], the weight in dried state on test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures on both ground-raised and ground-cutting slopes was found to be higher and showed similar characteristics statistically. As a result of survey on the surface-covering degree of ground-raised slopes, nine weeks after test construction, test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures showed commonly more than 70% of surface-covering degree, but other test spots showed only below 35% of surface covering degree; especially in case of test spots by Verdvol seed spray measures, they showed 10% of the lowest surface-covering. Surface-covering degree on the test spot of ground-cutting slopes nine weeks after test construction showed more than 75% both executed by Coir net with Seed spray construction method and executed by furrow-digger with Seed spray and Straw mat-mulching measures. As a result of survey on appearing plants on the test spots, there dominates Eragrostis curvula both on ground-raised slopes and on ground-cutting slopes with other seeding plant life's lower breeding and there appear intruders, such as Setaria viridis Beauv, Digitaria sanguinalis Scop, and Chenopodium album var.centrorubrum Makino. As for water-borne excavation and soil's washing-away on the slopes, there happened less washing-away and water-borne excavation with good breeding of plant life on test spots executed both by Coir net with Seed spray construction method and by furrow-digger with Seed spray and Straw mat-mulching measures, but there happened much more soil's washing-away along with water-home excavation at the test spot executed by Seed spray with measures. After the research results of test construction sites are examined overall, it's presumed that furrow-digger with Seed spray and Straw mat-mulching measures [interval between lines is 40cm, 5cm in depth] will be preferred to prevent erosion and water-home excavation of slopes located within the construction sites.

• 한국안전학회지
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• 제26권2호
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• pp.26-31
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• 2011

In this paper, the safety diagnosis using thermal image analysis is described for power equipments. The conventional three-phase comparison method has only provided the results of thermal comparison for the equipments. The proposed method defines the conditions of poor connection by visual checks, and supports the criteria with each thermal rise step. As a result, the thermal difference from $5^{\circ}C$ to $10^{\circ}C$ meant the warning state. In addition, the thermal difference more than $10^{\circ}C$ meant that the connection status was unbalanced. In this case, the countermeasure might be the internal load distribution. If the thermal difference more than $20^{\circ}C$ is observed, it means a hot spot at the poor connection. If the hot spot is observed all over the surface, its cause was the unbalanced load, which made the conductive parts discolored and raised the possibility of oxidization or $Cu_2O$ generation. This diagnostic technology employing thermal image analysis method can be directly applied in the field and ensures the safety of equipments.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.1996-2000
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• 2008

In autothermal reforming reaction, oxygen to carbon ratio (OCR) and steam to carbon ratio (SCR) are significant factors, which control temperature and carbon deposition into the reactor. The OCR is more sensitive than the SCR to affect the temperature distribution and reforming efficiency. In conventional operation, hydrocarbon fuel, steam, and oxygen was homogeneously mixed and injected into the reactor in order to get hydrogen-rich gas. The temperature was abruptly raised due to fast oxidation reaction in the former part of the reactor. Deactivation of packed catalysts can be accelerated there. In the present study, therefore, the effect of the oxygen distribution is introduced and investigated to suppress the carbon deposition and to maintain the reactor in the mild operating temperature (e.g., $700{\sim}800^{\circ}C$). In order to investigate the effect numerically, the following models are adopted; heterogeneous reaction model and two-medium model for heat balance.

• 생명과학회지
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• 제20권9호
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• pp.1294-1298
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• 2010

흰반점바이러스(WSSV)는 새우양식산업에 막대한 경제적 손실을 일으키는 가장 치명적인 바이러스성 질병 원인체 중 하나이다. 본 연구는 인위적인 실험모델로서 WSSV에 대한 자주새우(Crangon affinis)의 감수성을 확인하고자 실험을 수행하였다. WSSV가 희석된 수조 내에서 침지법으로 감염된 새우는 감염 후 7일째에 100% 누적폐사율을 보여 자주새우가 WSSV에 대해 매우 높은 감수성을 갖고 있음을 확인하였다. 또한 재조합단백질인 rVP466에 대한 항혈청의 중화효과를 확인하기 위해 항혈청과 반응시킨 바이러스액($1{\times}10^4$ 배로 희석된 WSSV)을 이용하여 침지법으로 자주새우에 대해 공격실험(challenge test)을 수행하였다. 실험 결과, WSSV로 challenge한 감염대조구(positive control)의 새우들은 감염 후 5일째에 100% 폐사하였으며, WSSV와 rVP466 항혈청을 1:0.01, 1:0.1, 1:1로 혼합한 액으로 challenge한 새우들은 감염 후 14일째에 각각 100%, 68.8%, 68.8%의 누적폐사율을 보였다. 따라서 본 연구 결과는 연안서식종인 자주새우가 양식장으로부터 배출된 WSSV에 의해 자연상태에서 감염 될 수 있는 가능성과 함께 항혈청에 대한 중화효과를 나타냄으로써 겨울철 저수온기에 WSSV 감염을 위한 대체 실험생물로서의 유용성을 확인하였다.

• Parasites, Hosts and Diseases
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• 제51권1호
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• pp.125-128
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• 2013

In April 2010, pruritic symptoms were recognized in 3 privately-owned Siamese cats raised in Gwangju, Korea. Examination of ear canals revealed dark brown, ceruminous otic exudates that contain numerous live mites at various developmental stages. Based on morphological characteristics of adult mites in which caruncles were present on legs 1 and 2 in adult females and on legs 1, 2, 3, and 4 in adult males while the tarsus of leg 3 in both sexes was equipped with 2 long setae, the mite was identified as Otodectes cynotis. Ten ear mite-free domestic shorthaired cats were experimentally infected with O. cynotis to evaluate the efficacy of 10% imidacloprid/1% moxidectin spot-on. Live mites were recovered from 1 of 10 treated cats on day 9 post-treatment (PT) while no live mites were observed from the ear canals of treated cats on days 16 and 30 PT. The efficacy of 10% imidacloprid/1% moxidectin spot-on on O. cynotis in cats was, therefore, 90% on day 9 and 100% on days 16 and 30 PT. This is the first report of otodectosis in 3 cats naturally infested with O. cynotis in Gwang-ju, Korea. Both natural and experimental infestations were successfully treated with 10% imidacloprid/1% moxidectin spot-on.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제11권1호
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• pp.65-70
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• 2011

The increased disk rotational velocity to improve the data transfer rate has raised up many serious problems in its servo control system which should control the position and velocity of a spot relative to a rotating disk. This paper proposes gain-scheduling-based track-seek control for single stage actuator of hard disk drives. Gain scheduling is a technique that can extend the validity of the linearization approach to a range of operating points and one of the most popular approaches to nonlinear control design. The proposed method schedules controller gains to improve the transient response and minimize overshoot during the functions of the read/write head positioning servomechanism for the seek control. The validity of the proposed method is demonstrated through stability analysis and simulation results.