• 정보처리학회논문지A
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• 제16A권1호
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• pp.17-26
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• 2009

무선센서네트워크는 위험 지역에서의 데이터 수집 용도로 최근 각광받고 있는 기술이다. 하지만 위험한 지역에서는 다수 노드들에서 동시 다발적인 장애발생 위험이 크기 때문에 대규모의 장애를 빠르게 복구시키기 위한 자가 복구 능력을 높여야 한다. 기존의 라우팅 프로토콜들은 하나의 노드에서 발생한 장애는 빠르게 복구하지만 다수의 노드들에서 장애 발생시 이에 효과적으로 대처하지 못한다. 이에 본 논문에서는 대규모 장애 발생시 이를 빠르게 복구하기 위한LSFA(Large Scale Failure Adaptive Routing Protocol)을 제안한다. LSFA는 다수의 노드들에 장애가 발생하여 데이터 전송이 이루어지지 못하는 환경에서 장애를 빠르게 감지하고 라우팅 주기를 적응적으로 조절하여 빠른 시간에 네트워크를 복구한다. LSFA는 패킷손실 정도를 장애발생 판단의 기준으로 사용하며 장애를 감지하면 라우팅 주기를 짧게 하여 장애가 발생한 사실이 네트워크에 빠르게 퍼지도록 한다. 베이스스테이션으로의 경로를 유지하고 있는 노드가 주위에 장애가 발생한 사실을 감지하면 자신의 라우팅 정보를 빠르게 전파시켜 장애 복구가 빠르게 이루어지도록 한다. 실험을 통하여 LSFA가 다른 프로토콜들에 비해 적은 패킷을 사용하면서도 장애를 빠르게 복구함을 보인다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제22권5호
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• pp.357-367
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• 2022

Background: Low-dose dexmedetomidine may be a suitable alternative to opioids for pediatric ambulatory procedures under general anesthesia (GA). However, the recovery profile remains unclear. Herein, we aimed to evaluate the effects of low-dose dexmedetomidine on the recovery profile of children. Methods: Seventy-two children undergoing ambulatory oral rehabilitation under GA were randomly and equally distributed into two groups (D and F). Group D received an infusion of dexmedetomidine 0.25 ㎍/kg for 4 min for induction, followed by maintenance of 0.4 ㎍/kg/h. Group F received an infusion of fentanyl 1 ㎍/kg over 4 min for induction, followed by maintenance at 1 ㎍/kg/h. The primary outcome was the extubation time. The secondary outcomes were awakening time, end-tidal sevoflurane (ET-Sevo) requirement, change in hemodynamic parameters, Richmond Agitation-Sedation Scale (RASS), Children's Hospital of Eastern Ontario pain scale (CHEOPS) score, length of PACU stay, and incidence of adverse events. Results: Statistically significant differences were observed in the recovery profile between the groups: the median time for extubation was 3.65 (3.44-6.2) vs. 6.25 (4.21-7) minutes in groups D vs. F (P=0.001), respectively, while the corresponding awakening times were 19 (18.75-21) and 22.5 (22-24) minutes, respectively (P < 0.001). The mean ET-Sevo was low in group D (1.1 vs. 1.2; P < 0.001). The heart rate was significantly low across all time points in group D, without resulting in bradycardia. The median RASS and CHEOPS scores were also significantly lower in group D. No significant differences were observed in the mean arterial pressure, incidence of adverse events, or length of PACU stay. Conclusion: Low-dose dexmedetomidine was more effective than fentanyl as an opioid substitute at providing a better recovery profile in pediatric ambulatory oral rehabilitation under GA. Dexmedetomidine also significantly reduced sevoflurane consumption without causing adverse events or prolonging hospital stay.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.263-271
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• 2006

In this study, $20\;Nm^3/hr$ scale compact hydrogen generator which can be apply to the hydrogen station was manufactured and tested. The design of $20\;Nm^3/hr$ scale compact hydrogen generator was upgraded on the base of $5\;Nm^3/hr$ scale plate hydrogen generator concept stacking the plate reactors. Ideas for improving system efficiency such as heat recovery from the exhaust, exhaust duct which is especially design for plate type reactor, reinforcement of insulation, enlargement of heat exchange area of reactor, introduction of desulphurizer reactor and PROX rector in a compact design etc. were applied. From the performance test, we can learn that the $20\;Nm^3/hr$ scale compact hydrogen generator can be operated steadily at 100% road condition and the methane conversion of over 94%(at S/C=3.75) was obtained. This result shows that the concept of plate type hydrogen generator can be scale-up to the $20\;Nm^3/hr$ scale and fit for hydrogen generator for on site hydrogen station application.

• 대한정형도수물리치료학회지
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• 제15권2호
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• pp.88-92
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• 2009

Purpose: The purpose of this study was to evaluate the effects of exercise on functional status in stroke patients. The understanding of the course of recovery after stroke and factors affecting outcomes are important in planning and evaluation of stroke rehabilitation. Methods: To predict the outcom of stroke patient, we measured in the beginnig of rehabilitation, on 36 patients. The variables were gender, age, duration of rehabilitation treatment, motor assessment scale(MAS). Results: The patient age in 50-59 years was 41.7%. The stroke left side motor weakness were found 55.6%. The duration of rehabilitation treatment in 2-3 months was 50.0%. In the difference 24.63 for motor assessment scale after a rehabilitation treatment had significantly higher than 10.86 for motor assessment scale at initial. Gender by motor assessment scale after a rehabilitation treatment was 25.7 in male and 23.2 in female(P<0.05). Past history by motor assessment scale after a rehabilitation treatment was 26.7 in hypertension, 24.6 in cardiac disorder and 21.8 in diabetes mellitus(P<0.05). Conclusion: The subjective symptoms of motor assessment scale after a rehabilitation treatment was significantly associated with gender.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.37-42
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• 2006

In this study, $20Nm^3/hr$ scale compact hydrogen generator which can be apply to the hydrogen station was tested for hydrogen station application. $20Nm^3/hr$ scale compact hydrogen generator was developed by upgrading concept of stacking plate reactor from former $20Nm^3/hr$ scale plate hydrogen generator. concepts for improving system efficiency and performance include such as idea of heat recovery from the exhaust, exhaust duct which is especially design for plate type reactor reinforcement of insulation, enlargement of heat exchange area of reactor, introduction of desulphurizer reactor and PROX rector in a compact design, introduction of back fire protection structure of plate burner and so on, We can learn that final prototype of scale-up $20Nm^3/hr$ scale compact hydrogen generator can be operated steadily in 100% road at which over 94% of methane conversion(S/C=3.75) was obtained. In case of making up the weak point, we expect that it is possible to apply to hydrogen station by way of showing an example.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1812-1813
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• 2011

• Archives of Reconstructive Microsurgery
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• 제21권2호
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• pp.81-85
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• 2012

Purpose: Saturday night palsy is a transient form of nerve palsy that occurs after a prolonged period of direct pressure on the course of radial nerve by one's own or spouse's head. Although commonly encountered, there have been only few studies concerning its convalescence. The purpose of this study is to predict the prognosis of Saturday night palsy based on the causes, time to recovery and degree of recovery. Materials and Methods: Retrospective study of 20 patients who were diagnosed compression radial nerve palsy was performed. The average age was 36.7 years old and the mean follow-up period was 19.6 months. We investigated sleeping hours as an indirect measure of nerve compression time, recovery of wrist and finger extension, DASH score on the monthly based follow up. Results: The mean sleeping hours was 5.8 hours and all patients showed full recovery of wrist and fingers extension with the mean duration of symptom for 3.2 months. DASH score was an average 1.53 at the last follow up and we found no statistical significance between the time to recovery and the sleeping hours. Conclusion: Complete natural recovery can be expected in compression radial nerve palsy in this study without correlation with sleeping time. Accurate diagnosis is important in order to avoid unnecessary therapeutic intervention and further study should be accomplished for clarifying the related prognostic factors in larger scale of the cases.

• 자원리싸이클링
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• 제24권3호
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• pp.27-33
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• 2015

제강분진(Electric Arc Furnace Dusts)은 유해폐기물로 지정되어있는 유해한 환경오염물질이다. 이 분진은 철강산업의 부산물로써 철, 아연, 니켈, 구리 등 많은 유가금속을 포함하고 있어 적절한 처리를 거치면 폐기물이 아닌 자원으로 재활용이 가능하다. 본 연구에서는 국내 전기로에서 발생하는 제강분진을 대상으로 가장 높은 함유량을 가진 아연의 회수를 위한 최적조건을 도출하기 위해 습식침출법을 적용하였다. 분진과 황산의 고액비, 침출시간, $MnO_2$ 투입량 등의 조건을 종합하여 실험을 진행하여 최적 아연회수조건을 도출하였다. 황산농도 3 M, 고액비 1:2, 철 제거를 위한 폭기 1.8 L/min 강도로 2시간에서 95%의 아연 회수율이 관찰되었다. 그러나, 현장 적용의 현실성을 고려한 다른 최적의 조건은 저농도 황산과 $MnO_2$ 3.5 g을 투입했을 경우 약 80 %의 아연 회수율을 나타내었다.

• KSBB Journal
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• 제20권4호
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• pp.317-322
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• 2005

섬유성 기질을 물 가수분해하여 생긴 당을 최대한 회수하는 여러 회수방법을 조사하였다. 사용한 전처리 조건은 반응온도가 $170\~180^{\circ}C$, 반응시간이 1시간이었다. 반응 온도가 170에서 $180^{\circ}C$로 증가함에 따라 xylan의 용해율은 증가하지만 $180^{\circ}C$ 이상에서는 상당양의 당이 분해됨을 알 수 있었다. 가수분해 결과로부터 남은 고체기질과 당화액에서 얻은 당의 물질수지를 조사하였는데 glucan의 경우는 비교적 잘 맞으나, 헤미셀룰로오스는 처리되지 않은 기질에 포함된 초기양과 비교할 때 상당한 차이가 났다. 그래서 여러가지 회수방법을 고안하여 당의 물질수지를 조사한 결과 회수기간동안 열을 가하거나 초음파를 조사하는 방법과 같은 물리적인 자극을 주면 액상에서 헤미셀룰로오스 회수율이 증가되는 것이 확인되었다. 이런 사실로부터 당 회수시 기질이 크고 전처리 후 침출용매를 많이 사용할 수 없는 상업적인 공정의 경우 상당양의 올리고당이 고체기공내 갇혀 액상으로 회수되지 못할 것으로 생각된다.

• 한국입자에어로졸학회지
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• 제13권2호
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• pp.65-77
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• 2017

In recent large-scale semiconductor manufacturing cleanrooms, the energy consumption in outdoor air conditioning (OAC) systems to heat, humidify, cool and dehumidify outdoor air(OA) represents about 40~50 % of the total cleanroom power consumption required to maintain cleanroom environment. Therefore, the assessment of energy consumption in outdoor air conditioning systems is essential for reducing the outdoor air conditioning load for a cleanroom. In the present study, an experiment with an outdoor air flow rate of $1,000m^3/h$ was conducted to compare the energy consumption in steam humidification, simple air washer, exhaust air heat recovery type air washer and dry cooling coil(DCC) return water heat recovery type air washer OAC systems. Besides, a numerical analysis was carried out to evaluate the annual energy consumption of the aforementioned four OAC systems. It was shown that the simple air washer, exhaust air heat recovery type air washer and DCC return water heat recovery type air washer OAC systems using water spray humidification were more energy-efficient than the steam humidification OAC system. Furthermore the DCC return water heat recovery type air washer OAC system was the most energy-efficient.