• 한국해안해양공학회지
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• 제15권1호
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• pp.1-10
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• 2003

본 연구에서는 수평배수공법에 있어서 부압과 배수재 배치간격에 대한 영향을 일련의 실내실험을 통해 살펴보았다. 중형토조실험를 이용한 적정 부압 산정에 관한 실험결과 초기에 낮은 부압을 가하고 단계적으로 높은 부압을 가하는 것이 바람직하고, 높은 부압을 가하는 경우에 일어날 수 있는 배수재의 위치 변화를 작게 하며, 배수재로부터 거리에 따라 함수비를 균등하게 감소시킴으로서 함수비 저감 효과가 큰 것으로 나타났다. 그리고. 신사전 등(1988씰 제안식을 이용하여 배수재의 평균 타설간격을 산정하여 Barron(1948)의 이론식을 이용한 계산 값과 신사전 제 침하량 측정으로부터 구한 시간 경과에 따른 압밀도를 비교한 결과 실측 압밀곡선은 신사전 등(19880의 평균타설간격(dm)을 적용한 실측 압밀곡선과 거의 유사한 경향을 보였다. 따라서, 현장에서 수평배수재를 설치한 준설지반 의 배수재 배치간격과 압밀속도를 계산함에 있어서 신사전등과 Barron의 이론식 적용이 가능할 것으로 판단된다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제25권4호
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• pp.81-91
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• 2019

Purpose: Since infectious disease hospitals are premised on emergency operations, the operational efficiency of secured personnel, equipment, facilities, etc. is relatively low. In order to increase such normal operational efficiency, it is necessary to flexibly operate facilities and operations during normal and emergency times. The purpose of this study is to suggest the architectural planning method focusing on the space composition and circulation of the regional infectious disease hospital which can increase the operational efficiency in the private hospitals. Methods: Through literature review, functional requirements of infectious disease hospitals were identified, and related personnels inter-views and field surveys were conducted to understand the spatial composition and circulation requirements of infectious disease hospitals. Results: Through the complete separation between the negative pressure zone and the general zone, even when the negative pressure zone is completely closed, the general zone should be operated separately to achieve operational efficiency. In addition, the separation of the negative pressure zone and the general zone should simultaneously consider the optimal space configuration and movement for each function while the zone settings match in the floor plan of each department and the overall cross-sectional configuration of the hospital. Implications: Infectious disease hospitals intended to be installed in private hospitals should not apply excessive space just for safety reasons and should plan to ensure their operational efficiency.

• 한국산업보건학회지
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• 제30권1호
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• pp.28-38
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• 2020

Objectives: The purpose of this study is to identify the perceived problems of and suggest improvement measures for asbestos abatement companies in support of asbestos-related systems and policies. Methods: For this study a questionnaire was prepared consisting of current work (two questions), the contribution and necessity of a risk assessment system for asbestos abatement (two questions), and problems with and improvement measures for systems and policies (nine questions). The questionnaires were sent to 2,170 asbestos abatement companies and were returned by 83 companies (return rate = 3.8%). We conducted frequency analysis, ANOVA, and a Chi-squared test at the 5% significance level. Results: Asbestos abatement companies expressed difficulties with complying with wet work (43% of unenrolled managers), negative pressure enclosure (36% of all respondents), and installation and use of decontamination units (26% of all respondents) as stipulated in the relevant regulations. In addition, 43% of the respondents expressed concerns that the expertise of the company was not considered during bidding for asbestos abatement and hoped that an advantage (e.g., bid point) would be given to the upper grades for asbestos risk assessment (38%). Asbestos abatement companies generally rented and used negative pressure devices (including negative pressure recording devices) and suggested that periodic calibration (32%) is needed to ensure the performance of the rented equipment. Finally, the respondents asked for clear definitions for three situations specified in the Occupational Safety and Health Acts: (1) temporarily leaving the asbestos abatement workplace; (2) tasks with less airborne asbestos; and (3) physically breaking or cutting using a machine. Conclusions: The problems and improvement measures identified in this study of asbestos abatement companies can be utilized as fundamental information for the improvement of the systems and policies for safe asbestos abatement.

• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.341-348
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• 2003

Mechanical stimuli to the cardiac myocytes initiate many biochemical and physiological events. Stretch-activated cation channels have been suggested to mediate these events. In this study, cell-attached and inside-out excised-patch clamp methods were used to identify stretch-activated cation channels in adult rat atrial myocytes. Channel openings were increased in cell-attached configuration when negative pressure was applied to the pipette, and also in inside-out excised patches by negative pressure. The channel was not permeable to $Cl^-$, $Na^+$ and $Cs^+$, but selectively permeable to $K^+$, and the degree of activation was dependent on the magnitude of negative pressure (full activation at ${\sim} -50 mmHg). In symmetrical 140 mM KCl, the slope conductance was $51.2{\pm}3$ pS between the potentials of -80 and 0 mV and $55{\pm}6$ pS between 0 and +80 mV (n=5). Glibenclamide ($100{mu}M$) or ATP (2 mM) failed to block the channel openings, indicating that it is not ATP-sensitive $K^+$ channel. Arachidonic acid ($30{mu}M$), which has been shown to activate a $K^+$ channel cooperatively with membrane stretch, did not affect the channel activity. $GdCl_3$ ($100{mu}M$) also did not alter the activity. These results demonstrate that the mechanical stretch in rat atrial myocytes activates a novel $K^+$-selective cation channel, which is not associated with other $K^+$ channels such as ATP-sensitive and arachidonic acid-activated $K^+$ channel.

• Journal of Chest Surgery
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• 제40권4호
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• pp.313-316
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• 2007

전신마취 회복기에 발생하는 음압성 페부종은 드물게 발생하나, 여러 종류의 수술 후 발생할 수 있는 잠재적으로 심각한 합병증이다 음압성 페부종의 발생 기전은 기관 내 튜브 발관 후 심한 자발적인 호흡시도와 성문폐쇄 및 후두경련으로 인한 기도폐쇄와 연관하여 현저하게 기도 내 음압이 상승하여 생긴다고 한다. 저자들은 건장한 26세 남자 환자에서 양성 늑골종양에 대한 늑골 부분절제술 후 기관 내 튜브 발관 후 심한 음압성 폐부종과 각혈이 발생하였으나 성공적으로 보존적 치료를 시행하였다. 이에 문헌고찰과 함께 보고한다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제24권2호
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• pp.37-44
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• 2018

Purpose: This study investigates the influences of coughing direction and healthcare worker's location on the transport characteristics of coughed particles in airborne infection isolation room (AIIR), which is commonly called negative pressure isolation room, with a downward ventilation system. Methods: Computational Fluid Dynamics (CFD) was used to simulate the airflow and for tracing the behavior of particles. Results: The results show that the airflow pattern and coughing direction have a significant influence on the characteristics of particle dispersion and deposition. When healthcare workers are in the isolation room with the patient who is lying on the bed, it is recommended to be located far from the anteroom to reduce the exposures from infectious particles. And when the patient is lying, it is more effective in removing particles than when the patient is in Fowler's position. Although it is an isolation room that produces unidirectional flow, coughing particles can spread to the whole room and a large number of particles can be deposited onto patient, bed, side rails, healthcare worker, ceiling, floor, and sidewall. Implications: Following the patients' discharge or transfer, terminal cleaning of the vacated room, furniture, and all clinical equipment is essential. Also, it is necessary to establish detailed standard operating procedure (SOP) in order to reduce the risk of cross-contamination.

• 유기물자원화
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• 제21권4호
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• pp.50-61
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• 2013

교내 식당에서 분리 수거된 음식물류 폐기물에서 재생 에너지인 메탄가스를 생산하기 위해 혐기성 소화시스템에 대한 연구가 수행되었다. 1차 실험에서 침출수 인발/반송도 없고 혼합도 없는, 침출수 인발/반송은 없고 혼합이 있는, 침출수 인발/반송은 있고 혼합이 없는, 그리고 침출수 인발/반송은 있고 혼합이 있는 4개의 혐기성 시스템에서 침출수 인발/반송은 있고 혼합이 없는 시스템에서 가스발생이 가장 많은 것으로 나타났다. 반응조 혼합이 없고 침출수 인발/반송이 수행되는 시스템에서는 침출수의 반응조 내 침출수 유출속도가 빠른 경우에 혐기성 반응이 활발히 일어난 것으로 관찰되었다. 가스수집기 무게가 1kg이고 음식물류 폐기물 C/N비가 10이상이 되는 경우 혐기성 반응조의 가스가 소모되어 가스수집기에 부압이 걸리는 것이 관찰되었는데, 이에 대한 원인을 밝히는 것이 음식물류 폐기물에서 재생에너지를 회수하는데 필수적이다.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.308-312
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• 2017

Background Donor site seroma is the most common complication after latissimus dorsi (LD) flap harvest. This study aimed to evaluate the efficacy of negative-pressure wound therapy (NPWT) in preventing donor site seroma formation after the harvest of an LD flap for breast reconstruction. Methods In this prospective matched-pair study, 40 patients in whom an LD flap was harvested for breast reconstruction were enrolled. NPWT was used in 20 patients, and in a control group composed of another 20 patients, the conventional donor site dressing technique was used. Information was collected regarding postoperative complications, the incidence of seroma, total drainage volume, the number of percutaneous seroma aspirations, and the volume aspirated. Results In the NPWT group, the incidence of seroma formation after drain removal was significantly lower than in the control group (15% vs. 70%; odds ratio=0.07; relative risk, 0.24). Both the mean percutaneous aspirated volume (P =0.004) and the number of percutaneous aspirations (P=0.001) were also significantly lower in the NPWT group. There were no significant differences in the total drainage volume or the duration of wound drainage between the NPWT dressing group and the control group (P>0.05). Conclusions This study showed that NPWT is a promising tool for reducing the incidence of seroma formation after removing the drain at the donor site after LD flap harvesting. It is a simple and safe technique.

• Journal of Preventive Medicine and Public Health
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• 제33권1호
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• pp.69-75
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• 2000

Objectives : This study was conducted to evaluate the risk factors associated with cardiovascular disease. Methods : By the questionnaire, the informations of education level, monthly income, alcohol consumption and smoking habit were obtained. Height, weight and blood Pressure(BP) were measured by a trained nurse. The level of lasting blood sugar(FBS), total cholesterol, hight-density lipoprotein(HDL) cholesterol and triglyceride were tested by enzyne method about a group of 2888 males and 1696 females ages ever 20 who had never taken the medication for hypertension. Statistical analysis, ANOVA, stepwise multiple regression, correlation analysis were peformed using SAS package program. Results : There were significant differences among age groups in systolic and diastolic blood pressure, body mass index(BMI), FBS, triglyceride and cholesterol except HDL-cholesterol. The risk factors associated with systolic and diastolic BP significantly in male were BMI, age, alcohol intake, but in female BMI, age. Smoking habit had a significant negative correlation with BP in both sex. In the group of mild hypertension ($\geq140\;mmHg\;or\geq90\;mmHg$ defined by JNC-VI) and hypertension ($\geq160\;mmHg\;or\;\geq95\;mmHg$ defined by WHO), the percent of diabetes $(FBS\geq140\;mg/dl)$, hypercholesterolemia $(\geq240mg/dl)$, and hypertriglyceridemia $(\geq200\;mg/dl)$ were significantly higher compared with normal group in male and female. BMI, and alcohol consumption had a positive correlation with FBS, total cholesterol and triglyceride. Smoking had a positive correlation with cholesterol and triglyceride but negative correlation with HDL-cholesterol in male. The educational attainment had a negative correlation with BMI, FBS, total cholesterol and triglyceride in female. Conclusions : This study suggested that drinking, smoking, and BMI and lower educational level were associated with hypertension, hyperlipidemia and diabetes, but further evaluation was needed by prospective intervention study.

• Archives of Reconstructive Microsurgery
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• 제25권2호
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• pp.29-36
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• 2016

Purpose: Skin grafting is used for the transfer of cutaneous tissue from one site of the body to another. To improve graft survival, close contact between the graft and the wound bed is essential for vessels to grow across the gap. Here, we introduce an easy and efficient dressing method to improve graft survival. Materials and Methods: A retrospective chart review was performed to identify patients who underwent split thickness skin graft and negative pressure wound therapy (NPWT) or conventional treatment between January 2007 and April 2015. Overall, 25 consecutive patients were included in the NPWT group and 49 were included in the conventional dressing group to compare the outcome of the procedure. The data were obtained from medical records, including age, sex, cause of the skin defect, size of graft, time for healing, wound preparation time, and complications. Results: Of the NPWT group, the average wound size was $147.04{\pm}146.74cm^2$ (range, $9{\sim}900cm^2$). With the exception of one patient, all wounds healed without the need for further procedure. The average duration of time required for the NPWT group, which was defined as removal of stitches (or staples) and no need for additional active dressing, was $6.4{\pm}1.97days$ (range, 5~15 days). The average time for the conventional dressing group was $10.78{\pm}2.38days$ (range, 5~15 days). Conclusion: NPWT can be used to cover regions in which wound healing does not occur fully or when neither tie-over nor compressive dressings are applicable. This treatment also reduced wound healing time and allowed earlier patient mobilization and hospital discharge.