• 설비공학논문집
• /
• 제9권4호
• /
• pp.504-516
• /
• 1997

Recently scientists and engineers are developing a system to get waste heat of low-temperature level with advanced heat pump, which have not been used up to now. As the reason, it is necessary to examine capability of using waste heat which is raised up in the tunnel of subway out of widely distributed low-temperature waste heat in large cities. Therefore we surveyed thermal environment of the tunnel of subway in $S\check{o}my\check{o}n$, downtown of Pusan, from November 1995 to December 1996 and developed a program to predict the thermal environment of subway on the basis of experimental data and the geometries of tunnels. This paper has proved availability of waste heat of subway when the measured results obtained in subway in the winter time and the simulated results of thermal environment prediction program are compared, as well as has reported results of estimating reliability of the simulation program. As the result, the charateristics of thermal environment in the tunnel of subway in $S\check{o}my\check{o}n$ station in the winter time are to be followed; 1) temperature in the tunnel is about $10^{\circ}C$ higher than outside air temperature, 2) temperature change in the tunnel is less than that in the platform so that we may obtain stable heat source, 3) and when the measured results obtained in subway in the winter time and the simulated results of thermal environment prodiction program is compared, both results show similar tendency. Therefore, we confirm estimating reliability of the simulation program.

• Archives of Plastic Surgery
• /
• 제38권5호
• /
• pp.621-626
• /
• 2011

Purpose: Implant-based breast reconstruction has multiple advantages such as decreased morbidity, shorter operative time and faster recovery. However, postoperative infection with tissue expander increases medical cost and causes a delay in concurrent antineoplastic treatment. To reduce tissue expander infection, it is important to identify related risk factors and minimize them when possible. Methods: A retrospective review of patient records in a single breast cancer center was performed. Eighty-six tissue expanders were placed in 80 women for postmastectomy breast reconstruction. Variables including patients'age, body mass index (BMI), preoperative breast volume, operation time, drain indwelling time, postoperative seroma/hematoma formation, chemotherapy, and radiation therapy were evaluated. Infection was defined as the status that shows any symptom of local inflammation and identification of pathogens. Representative values were compared through Student's t-test and univariate and multivariate analyses. Results: We examined 86 postmastectomy tissueexpanders which were placed between June 2004 and April 2010. Seven cases of tissue expander infection (8.1%) were identified. The infected tissue expander was removed in three of the cases. The relationship between BMI, and preoperative breast volume and that between infection and non-infection groups were significant ($p$ <0.05). Univariate analysis showed significant association between BMI ($p$=0.023) and preoperative breast volume ($p$=0.037). Multivariate analysis revealed that BMI and preoperative breast volume were independent variables regarding tissue expander infection. Conclusion: Certain characteristics of implant-based breast reconstruction patients increase infection rate of tissue expander. These risk factors should be monitored and evaluated before surgeries for more successful outcome.

• 여성건강간호학회지
• /
• 제8권3호
• /
• pp.412-423
• /
• 2002

This study was designed to evaluate the effect of pelvic floor muscle exercise using biofeedback and electrical stimulation after normal vaginal delivery. The data were collected from November 1999 to April 2000 at a university hospital located in Seoul, Korea. Out of 49 women with normal vaginal delivery, 25 of experimental group(with exercise) and 24 of control group(without exercise) were questioned about lower urinary symptoms, discomfort during sexual intercourse and daily life. The maximum pressure of pelvic floor muscle contraction(MPPFMC) and duration of pelvic floor muscle contraction(DPFMC) were measured at pre-treatment, the end of treatment and 8 weeks after a treatment program. The pelvic floor muscle exercise program(using biofeedback and electrical stimulation) was applied to the experimental group twice a week for 4 weeks at the incontinence clinic and the pelvic floor muscle exercise at home for that time and more 8 weeks. Data were analyzed by t-test, $x^2$-test, Fisher's exact test and the repeated measures ANOVA. The results were as follows; 1) MPPFMC(p=0.000) and DPFMC(p=0.021) were significantly increased in the experimental group. 2) In the lower urinary symptoms, daily frequency(p=0.001), nocturia(p=0.002), incontinence episode(p=0.016), stress incontinence(p=0.012), quantity of incontinence(p=0.026), straining(p=0.041), and strength of stream(p=0.009) were significantly decreased in the experimental group. 3) Discomfort during sexual intercourse had not a significant difference between the two groups, which was not significantly decreased as time passed. 4) In the discomfort during daily life, activity restriction(p=0.042), exercise restriction (p=0.008), interpersonal relationship restriction(p=0.046), and discomfort of general life(p=0.027) showed a significant difference between the two groups, which were not significantly decreased as time passed. In conclusion, it is suggested that the pelvic floor muscle exercise using biofeedback and electrical stimulation might be a safer and more effective program for the improvement of postpartum pelvic muscle contraction.

• 한국수소및신에너지학회논문집
• /
• 제16권2호
• /
• pp.136-141
• /
• 2005

Li-doped NiO was synthesized by molten salt method. $LiNO_3$-LiOH flux was used as a source for Li doping. $NiCl_2$ was added to the molten Li flux and then processed to make the Li-doped NiO material. Li:Ni ratios were maintained from 5:1 to 30:1 during the synthetic procedure and the Li doping amount of synthesized materials were found between 0.086-0.190 as a Li ion to Ni ion ratio. Li doping did not change the basic cubic structural characteristics of NiO as evidenced by XRD studies, however the lattice parameter decreased from 0.41769nm in pure NiO to 0.41271nm as Li doping amount increased. Hydrogen gas sensors were fabricated using these materials as thick films on alumina substrates. The half surface of each sensor was coated with the Pt catalyst. The sensor when exposed to the hydrogen gas blended in air, heated up the catalytic surface leaving rest half surface (without catalyst) cold. The thermoelectric voltage thus built up along the hot and cold surface of the Li-doped NiO made the basis for detecting hydrogen gas. The linearity of the voltage signal vs $H_2$ concentration was checked up to 4% of $H_2$ in air (as higher concentrations above 4.65% are explosive in air) using Li doped NiO of Li ion/Ni ion=0.111 as the sensor material. The response time T90 and the recovery time RT90 were less than 25 sec. There was minimum interference of other gases and hence $H_2$ gas can easily be detected.

• 핵의학기술
• /
• 제25권1호
• /
• pp.34-40
• /
• 2021

[목 적] 의료기관의 핵의학 검사실에서 신규검사를 도입하거나 사용하던 시약을 변경하게 되는 경우 절차에 따라 검사의 특성이 분석되고 시약에 대한 평가가 이루어져야 한다. 그러나 요구되어지는 비교실험을 모두 수행하기 위해서는 몇 가지 필요한 조건이 충족되어야 하는데, 첫째 각 검사별로 수행하기에 충분한 검체량이 준비되어야하며, 둘째 비교실험에 적용 가능한 다양한 시약의 공급이 가능해야한다. 충분한 비교실험이 이루어졌다고 하더라도 변경된 시약에 의한 데이터 변동이 전체 환자데이터 변동을 의미하는 것에는 한계가 있으므로 검사실에서 시약이 변경되는 것에 대한 부담이 있다. 이러한 다양한 어려움으로 검사실에서의 시약변경은 제한적으로 이루어지고 있다. 본원에서는 원할한 경쟁 입찰을 도입하기 위하여 검사별로 radioimmunoassay(RIA)시약을 전수조사하고 비교실험을 통해 검사실에서 사용가능한 시약범위를 설정하였다. 이 과정을 공유하고자 하였다. [대상 및 방법] 본원 핵의학 검체 검사실에서 시행하고 있는 검사는 위탁검사를 제외하고 총 20종목이다. 각각의 검사별로 외부정도관리와 기관간 정도관리 결과보고서를 참고로 사용가능한 RIA시약을 전수 조사하였고, 각 시약에 대한 메뉴얼을 확보하였다. 각각의 시약마다 메뉴얼을 확인하여 검사 방법과 incubation시간, 검사 시 필요한 검체량, 시약량 등을 확인하여 본 검사실에서 사용가능한지 여부에 따라 시약 1차 선정을 하였다. 1차 선정된 시약을 100 test기준으로 2 kit씩 공급받아 데이터 상관성시험, 민감도, 회수율, 희석시험을 진행하였고, 비교실험 결과에 따라 시약을 2차 선정하였다. 1, 2차 선정을 통과한 시약을 경쟁 입찰리스트로 제출하였다. 검사 시약을 단수로 지정할 경우에는 1차, 2차 선정 과정에서 얻은 자료로 단수지정 사유서를 작성하였다. [결 과] 각각의 시약마다 매뉴얼을 확인하여 시약 1차 선정에서 제외되는 경우는 각 검사의 현재 Turn Around Time(TAT)보다 길어지는 경우와 검사 시 사용 시약량이 많아 장비사용이 불가능한 경우였다. 1차 선정에서 사용가능한 시약이 1개인 경우는 5종목 squamous cell carcinoma antigen(SCC Ag), 𝛽-human chorionic gonadotropin(𝛽-HCG), vitamin B12, folate, free testosterone 이었고, 2개인 경우는 8종목 (CA19-9, CA125, CA72-4, ferritin, thyroglobulin antibody(TG Ab), microsomal antibody(Mic Ab), thyroid stimulating hormone-receptor-antibody(TSH-R-Ab), calcitonin), 3개인 경우는 5종목(triiodothyronine(T3), Free T3, Free T4, TSH, intact parathyroid hormone(intact PTH)), 4개인 경우는 2종목(carcinoembryonic antigen(CEA), TG)이었다. 2차 최종 선정결과 사용가능한 시약이 3개인 것은 T3, Free T3, Free T4, TSH, CEA, 2개인 것은 TG Ab, Mic Ab, TSH-R-Ab, CA125, CA72-4, intact PTH, calcitonin이었다. 단수 지정된 종목은 ferritin, TG, CA19-9, SCC, 𝛽-HCG, vitamin B12, folate, free testosterone이었다. 2차 선정에서 제외된 사유에는 비교실험을 위한 시약공급이 안된 경우와 데이터 재현성에 문제가 있었던 경우, 데이터 변동에 대한 수용이 불가능하다고 판단되는 경우였다. 비교실험 시 가장 문제가 되는 부분은 검체 수집이었다. 검사건수가 많고 검사 시 필요한 검체량이 적은 경우에는 문제가 되지 않았지만, 검사건수가 적은 경우(월 100건 이하)에는 다양한 농도 검체를 수집하기가 어려웠으며, 한번 검사 시 필요한 검체량이 상대적으로 많은 경우(100 uL이상)에는 회수율시험을 진행하기가 어려웠다. 또한 민감도 측정이나 희석시험을 위한 희석액이나 표준액0 물질이 부족한 경우도 문제점 중의 하나였다. [결 론] 검사시약 변경을 위한 비교실험 시 다양하고 충분한 검체 수집을 위해 적정한 준비기간이 필요하다. 또한 1회 검사 시 필요한 검체량 및 시약량에 따라 비교실험 시 필요한 총 검체량, 시약량 범위를 설정해 놓는다면 비교실험을 진행할 때마다 검체 수집과 실험계획을 세우는 데 부담이 줄어들 것이다.

• 자원리싸이클링
• /
• 제4권1호
• /
• pp.52-59
• /
• 1995

Co의 리싸이클링을 원활히 하기 위하여 괴상 superalloy 스크랩을 용융Zn으로 분해할 때의 최적처리조건을 조사하였다. 조사한 superalloy는 Co-기 Mar-M-509와 X-45 그리고 Ni-기 Rene 80이었다. Zn/스크랩 비율이 1.5~6.5인 장입물을 질소 분위기에서 $750~900^{\circ}C$에서 1~7.5시간 동안 가열하였다. 용융된 Zn은 스크랩을 용해하였고, Zn은 $850~900^{\circ}C$에서 4~6시간 동안 진공증류하여 제거되었다. Mar-M-509와 Rene 80의 최적 처리조건은 용해온도 약 $^850{\circ}C$, Zn/스크랩 비율 약 5, 그리고 용해시간 약 5.5시간이었다. Zn처리 superalloy 생성물은 쉽게 부스러졌으며, 산 용액에 의해 빠르게 침출되었다. Mar-M-509 또는 Rene 80의 경우, 미처리 스크랩(9mm 조각)을 화학양론양 5배의 6N HCl으로 $90^{\circ}C$에서 3시간 동안 처리하면 침출도는 약 1.5~7.2%에 지나지 않았으나, Zn처리 생성물(-20 메쉬의 것)의 침출도는 약 89.0~93.0%나 되었다.

• 자원환경지질
• /
• 제52권6호
• /
• pp.595-604
• /
• 2019

본 연구 목적은 비-가시성 금 정광을 마이크로웨이브-질산용출 시키고, 여과지를 이용하여 금을 단순하게 얻고자 하였다. 본 실험에서 사용된 시료의 경우 질산농도별로 마이크로웨이브-질산용출실험을 수행한 결과 Fe, Te, Ag 등은 완전용출(100%) 되었지만, Au는 용해되지 않았다. 용출용액을 3장의 여과지로 여과하여 SEM/EDS 분석한 결과 첫 번째, 두 번째 및 세 번째 여과지의 표면 및 단면 모두에서 Au가 검출되었다. 고체-잔류물이 포함된 여과지 3장을 모두 납-시금법에 사용한 결과 질산농도 모두에서 금 입자들이 회수되었다. 최대 금 입자(452.50g/t)가 얻어진 용출조건은 질산농도 6M에서 그리고 마이크로웨이브 조사시간 12분에서였다.

• Journal of Korean Neurosurgical Society
• /
• 제60권2호
• /
• pp.257-261
• /
• 2017

Objective : This study was conducted to assess the surgical results of one-stage posterior minimal laminectomy and video-assisted thoracoscopic surgery (VATS) for the treatment of thoracic dumbbell tumor and to describe its precise technique. In addition, we investigated the technique's usefulness and limitations. Methods : Seven cases of thoracic dumbbell tumor (two men and five women, mean age, 43 years) were analyzed retrospectively. Pathological findings included schwannoma in four patients, neurofibroma in two patients, and hemangioma in one patient. The location of tumors varied from T2/3 to T12/L1. Dumbbell tumors were resected by one-stage operation using posterior laminectomy followed by VATS without instrumentation. Clinical data were reviewed. Results : The mean follow-up period was 25 months (range, 3-58 months), and the operative time ranged from 255 to 385 min (mean, 331 min), with estimated blood loss ranging from 110 to 930 mL (mean, 348 mL). The tumor was completely resected without instrumentation and postoperative instability in all cases. Postoperative complications included atelectasis and facial anhydrosis in one case each. Conclusion : One-stage posterior minimal laminectomy and VATS may be a safe and less invasive technique for removal of thoracic dumbbell tumor without instability. This method has the advantage of early ambulation and rapid recovery because it reduces blood loss and postoperative pain.

• The Journal of Korean Physical Therapy
• /
• 제23권1호
• /
• pp.53-58
• /
• 2011

Purpose: The purpose of this study was to determine the effect of direct functional magnetic stimulation (FMS) of affected spinal cord on motor recovery following spinal cord injury in rats. Methods: After a contusion injury at the spinal level T9 using an NYU Impactor, functional magnetic stimulation was delivered by a magnetic stimulator through a round prototype coil (7 cm in diameter). Stimulation parameters were set as follows: repetition rate = 50 Hz (stimulus intensity 100% = 0.18 T), stimulation time = 20 min. Functional magnetic stimulation was administered twice a day, 5 days per week for 8 weeks starting 4 days after spinal cord injury. Functional magnetic stimulationwas delivered directly to the affected spinal cord. Outcomes of locomotor performance were assessed by the Basso Beattie Bresnahan (BBB) locomotor rating scale and by an inclined plane test weekly for 8 weeks. Results: In the BBB test, hindlimb motor function in the Functional magnetic stimulation group improved significantly more compared to the control group at 3, 4, 6, 7, and 8 weeks (p<0.05). In the inclined plane test, the angle of the plane in the functional magnetic stimulation group increased significantly more compared to the control group at 4, 5, 7, and 8 weeks (p<0.05). Conclusion: Our results demonstrate that direct Functional magnetic stimulation of the lesional site may have beneficial effects on motor improvement after spinal cord injury.

• 한국산학기술학회논문지
• /
• 제20권6호
• /
• pp.410-420
• /
• 2019

본 연구는 수면 대장내시경 검진자에게 복부마사지를 시행하여 장운동 회복과 복부팽만감에 미치는 효과를 파악하기 위하여 시도된 비동등성 대조군 전후 시차설계연구이다. 연구대상자는 C시, G병원에서 외래를 통해 수면 대장내시경 검진을 받는 실험군 22명, 대조군 22명으로 자료 수집 기간은 2018년 6월 1일부터 8월 25일까지였으며, 실험의 확산효과를 막기 위하여 대조군을 먼저 자료수집 한 후 시차를 두고 실험을 실시하였다. 자료분석은 IBM SPSS 24.0을 이용하여 자료를 분석하였으며, 대상자의 일반적 특성의 동질성을 검증하기 위하여 독립표본 t-test, $x^2-test$ 와 Fisher's exact probability test, 실험군, 대조군의 복부둘레 변화량에 대한 정규성을 검증하기 위하여 Shapiro-Wilk로 검증, 복부둘레의 사전 동질성을 검증하기 위하여 Mann-Whitney U test를 실시하였다. 실험처치 효과 검증은 Fisher's exact probability test, Friedman test와 Mann-Whitney U test로 검증하였다. 연구 결과, 복부마사지가 대장내시경 검진자의 가스배출 시간($x^2=19.75$, p<.001)과 복부팽만감($x^2=29.93$, p<.001)을 감소시켜, 수면 대장내시경 검진자의 가스팽만으로 인한 불편감을 완화하는 간호중재로 활용할 수 있을 것으로 생각된다.