사방댐 위치변화에 따른 토석류의 충격력 해석에 관한 연구 (The Study for Analysis of Impact Force of Debris Flow According to the Location of Check Dam)
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- 한국산학기술학회논문지
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- 제20권1호
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- pp.409-418
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- 2019
최근 기후 변화에 의한 집중호우는 산지에서 토석류를 발생시켜 많은 피해를 양산하고 있다. 연구의 목적은 토석류 발생 가능성이 높은 산지에 사방댐을 설치하였을 경우, 사방댐의 설치 위치에 따라 공급유량의 변화에 대하여 사방댐이 받는 충격력을 평가한 것이다. 연구방법으로는 수치해석모델을 이용하였고, 수치해석 모델은 침식과 퇴적 모델을 이용하여 유한차분법을 적용하였으며, 사방댐에 영향을 주는 토석류의 충격력은 유체의 연속성을 고려하여, 질량보존법칙과 운동량 보존 법칙을 만족하는 지배 방정식을 이용하였다. 수치모의를 한 결과 토석류는 도달 초기에 충격력의 Peak가 발생하였으며, 16sec~19sec 구간에서도 토석류의 Peak가 발생하였고, 공급유량을 증가시킨 경우 이 구간에서 여러 개의 토석류 충격력의 Peak가 발생하였다. 이는 공급유량의 증대로 인해 토석류의 유하 속도를 증가시키고, 증가된 속도는 물 입자와 토사의 충돌로 인해 에너지가 증대되고 있음을 보여준다. 따라서, 산지에 연속적으로 여러 기의 사방댐을 설치하려고 할 때 각 위치에서 사방댐이 받는 충격력을 조사할 필요가 있다. 본 연구의 결과는 비탈 경사면에서 토석류 제어를 목적으로 설치되는 구조물이 받는 충격력과 사면에서 사방댐의 적정 위치를 설정하는 데 좋은 정보를 제공할 것이다.
Recently, three-dimensional (3D) cell culture systems, which are superior to conventional two-dimensional (2D) vascular systems that mimic the in vivo environment, are being actively studied to reproduce drug responses and cell differentiation in organisms. Conventional two-dimensional cell culture methods (scaffold-based and non-scaffold-based) have a limited cell growth rate because the culture cannot supply the culture medium as consistently as microvessels. To solve this problem, we would like to propose a 3D culture system with an environment similar to living cells by continuously supplying the culture medium to the bottom of the 3D cell support. The 3D culture system is a structure in which microvascular structures are combined under a scaffold (agar, collagen, etc.) where cells can settle and grow. First, we have manufactured molds for the formation of four types of microvessel-mimicking chips: width / height ①100 ㎛ / 100 ㎛, ②100 ㎛ / 50 ㎛, ③ 150 ㎛ / 100 ㎛, and ④ 200 ㎛ / 100 ㎛. By injection molding, four types of microfluidic chips were made with GPPS (general purpose polystyrene), and a 100㎛-thick PDMS (polydimethylsiloxane) film was attached to the top of each microfluidic chip. As a result of observing the flow of the culture medium in the microchannel, it was confirmed that when the aspect ratio (height/width) of the microchannel is 1.5 or more, the fluid flows from the inlet to the outlet without a backflow phenomenon. In addition, the culture efficiency experiments of colorectal cancer cells (SW490) were performed in a 3D culture system in which PDMS films with different pore diameters (1/25/45 ㎛) were combined on a microfluidic chip. As a result, it was found that the cell growth rate increased up to 1.3 times and the cell death rate decreased by 71% as a result of the 3D culture system having a hole membrane with a diameter of 10 ㎛ or more compared to the conventional commercial. Based on the results of this study, it is possible to expand and build various 3D cell culture systems that can maximize cell culture efficiency by cell type by adjusting the shape of the microchannel, the size of the film hole, and the flow rate of the inlet.
This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with
The newborn human is the only mammalian whose mother does not have a food supply ready for it's offspring at birth. From two to four days usually elapse before the mother's supply If milk appears, and during this period, some kind of artificial feeding should be supplied to the infants. Because of this factor, there has been continued debate fog the past hundreds of years as to when the first feeding should be started Accordingly, many experiments were carried out by scholars and because of these, Pre-lateral feedings were believed to be necessary. Many types of pre-lateral feedings were tried and the conclusion was reached that glucose water was the best food for the first infants'feedings. Traditionally, This has been started 12 hours after birth. The causes for the 12 hours delay were thought to (1) provide rest for the infants: (2) prevent regurgitation ana vomiting which tended to be prevalent during this tine: (3) in cases of low weight infants, prevention of aspiration pneumonia. From recent studies of newborn physiology and as pediatric medicine has been rapidly advancing, many studies hare been carried out concerning the improvement of infant nutrition and the early feeding of infants has been emphasized. This author believes it would be very beneficial to try two different kinds of feedings for the infant. (1) experimental feedings ana (2) comparative feeding, and during this period to investigate and compare the infants blood sugar level, hematocrit, gamma globulin level weight changes and to observe the infant reaction ill order to search for a more desirable feeding program. This study was conducted from January to March 1974 with data related to 40 healthy newborn infants (male 21, female 19: weight, 2.79∼4.20㎏ : gestation, 39∼40 weeks) born at Ewha Womens University Hospital and the results obtained were as follows : 1. At time of birth the blood sugar level from the cord sample averaged 88.99㎎/100㎖, but the blood sugar level rapidly dropped after 2 to 3 hours and reached the lowest point after 10 to 11 hours (54.48㎎/100㎖) and rose again by the 24 hour time period (76.80㎎/100㎖). Changes in the blood sugar level of the experiments: groups and the compare-five group was not significantly different until the 6 to 7 hour period, but by the 10 to 11 hour period the blood sugar levels of the experimental group (49,10㎎/100㎖) and the comparative group (49.70㎎/100㎖) were lower than the remainder of the experimental groups. 9. There ware no significant weight changes between the two groups. Average weight at birth was 3.35㎏, but at the 24 hours period birth weight averaged 3.29㎏. (1.8% reduction of birth weight). It continually lowered until at 48 hours, average weight was 3.26㎏ (2.7% reduction from birth weight.) 3. Hematocrit readings showed no significant difference between the groups. Hematocrit, the average value at birth, was 28.07% and abruptly elevated to average 64.35% at the 2 to 3 hour period, then slowly lowered to an average of 59.67% at the 6 to 7 hour period, 55.10% at the 10 to 11 hour period, ana 53.70% at the 24 hour period. 4. At birth, average gamma globulin value averaged 1,39㎎/100㎖. and at the 24 hour period averaged 1,52㎎/100㎖ revealing no significant difference between the two feeding groups. 5. Such factors as voiding, passing of meconium, regurgitation and vomiting showed no significance between the two feeding groups. However, the number of infants voiding and passing meconium in the experimental groups during the first 12 hours was slightly greater. In general there was an increased tendency for regurgitation and. vomiting among a small group of the infants during the first 24 hours which thereafter decreased. 6. Fluid intake averaged 24.38cc at the first feeding and increased to average 30.48cc at the third feeding and further increased to 73. 00cc at the fifteenth feeding. Finally it was suggested that the most reasonable method of early feeding is to give less than 25cc of 5% glucose water and/or 8% powdered milk at 8 to 9 flours after birth in order to prevent hypoglycemia and dehydration.
본 연구에서는 산업분야에서 다양하게 이용되고 있는 연동펌프를 농축양액 주입장치로 사용한 관비장치를 개발하고 성능시험을 실시하였으며, 얻어진 결과는 다음과 같다. 튜브 내경별, 회전수별, 롤러수별 유량특성 시험결과 펌프 회전속도가 빨라짐에 따라 유량은 직선적으로 증가하였으며, 튜브 내경이 커질수록 기울기도 커졌으며, 롤러수가 3개일 때가 4개일 때의 유량 보다 더 많은 것으로 나타났다. 또한 튜브재질에 있어서는 복원력이 우수한 재질의 노프렌 튜브에서 유량이 많은 것으로 나타났다. 관비장치의 농축양액 주입위치에 따른 혼삽성능 실험결과 안정화 시간은 농축양액을 공급펌프의 흡입 측에 주입한 경우에는 17초, 공급펌프의 토출 측에 주입한 경우에는 16초 이었으며, EC는 안정화 구간에서 각각 1.42±0.05, 1.39±0.02 dS/m로 나타나 주입위치에 따른 영향은 크지 않은 것으로 판단된다. 측정 센서 설치위치에 따른 안정화시간은 주관에 삽입 설치한 경우에는 17초, 여수관에 설치한 경우에는 27초로 나타나 센서는 주관에 삽입 설치하는 것이 바람직한 것으로 판단된다. EC는 안정화 구간에서 각각 1.43±0.05, 1.45±0.07dS/m의 근소한 차이를 보였다. 시작기의 제어성능 실험결과 제어정밀도가 ±0.05dS/m로 나타나 제어성능이 우수한 것으로 나타났다. 농가 현장시험결과 개발한 관비장치에 의해 재배한 오이가 정상적인 생육을 하는 것으로 나타나 개발한 시험용 장치의 실용화가 이루어진다면 관비재배 농가에서 활용할 수 있을 것으로 판단된다.
In this thesis, I intend to study the translational and clinical interpretation through the syndrom of "Pyong-Yeol-Byong", and reached the following conclusions. 1. Eum-Yang-Kyo (陰陽交)' 1) Meaning: "Eum" means "Essential and vital energy" "Yang" means "Evil factor affecting health" and "Kyo" means "cross-struggle." 2) Location of disease: Heat evil enter Hyeol-Bun (血分) 3) Pathogenesis: Heat evil invade Eum-Bun (陰分) and struggles with Health energy, therefore Eum-Chung (陰精) is exhausted and Heat-evil doesn't disapper, it damage Eum and exhaust fluid. Reach fever, rapid pulse raving and unable to take meal, not controled by sweating and sceach death. 4) Particularity of Syndrome: Heat enter Hyol-Bun, and Evil factor is enough and Health energy is insufficient, so that reveal the symptoms of high fever, delirium with coma, unable to take meals. 5) Therapy: It clears Gi-Bun heat evil (氣分熱邪) by Gypsum, Rhizoma Anemarrhenae, Flos Lonicerae, Fructus Forsythiae, Fructus Gardeniae, Radix Scutellanae Rhizoma Coptidis, and cools Blood by Cornu Rhinoceri Asiatici, Radix Rehmanniae, Cortex Moutan Radicis, Dae-Chung-Yob (大靑葉) Radix Arnebiae Seu Lithospermi. 2. Poong Gweol (風厥) 1) Meaning: Poong means wind-evil, Gweol means reversing up. 2) Location of disease: Disease complexes with TaeYang (太陽) in outer part, and with So-Eum (少陰) in inner part. 3) Pathogenesis: Tae-Yang-Gyeong (太陽經) accept wind-evil and So-Eum-Gyeong (少陽經) Kidney Energy reverse up so that fidgetiness not resolves by sweating. 4) Particularity of Syndrome: There are outer symptoms of fever, hydrosis with inner symptoms of fidgetinessis. 5) Therapy: Reduce Jok-Tae-Yang (足太陽) and Supply Jok-So-Eum (足少陰) by accupuncture, so cure Poong Gweol and make balance between Yeong (營) and Wi (衛). 3. Scrofula coused by wind-evil (勞風) 1) Meaning: It means accepting wind evil rest less. 2) Location of Disease: It locates lung 3) Pathogenesis: Because of accepting wind-evil restless, he take scrofula with damaging lung. 4) Particularity of disease: It is lung disease of aversion to wind and shiver, nape-stiffiness, dim eyesight, cough, disphea, vomitting sputum, if one camnot vomit sputum, he died by damage of lung. 5) Therapy: The period of therapy is different by age or strength of health energy, so I think must prevent Eum deficiency and clear fever no reduced in lung. 4. Shin-Poong (腎風) 1) Meaning: It means taking edema by accepting wind-evil, because the kidney controls water. 2) Location of Disease: It is that wind-evil envade kidney. 3) Pathogenesis : Water evil of kidney with wind-heat rises up to face, reach edema, puffines s of the lower eyelid, floating pulse, bombus, yellowish urine, hydrosis and hand-heating, drymouth and excessive thirsty, walkless by heaviness, menstrual disfunction, restless and unable to take meals, unable to lie flat, heavy cough if lie flat, and accepting wind-evil by deficiency of kidney function, so the function of dredging the water passage is not smooth, symptom of water and symptom of wind reveal together. 4) Therapy: Remove wind-heat, promote diuresis to eliminate tile wetness-evil, supplement the dificiency of kidney's Eum. Finally, we can know that later Fever Disease Medicime (溫病學) is affected to the theory of "Pyong Yeol Byong" in 33th Chapter of SoMoon (素問).
This study was done to verify validity of nursing diagnoses related to difficulty in respiratory function. First, content validity was examined by an expert group considering the etiology and the signs / symptoms of three nursing diagnoses - ineffective airway clearance, ineffective breathing pattern, impaired gas exchange. Second, clinical validity was examined by comparing the frequencies of the etiologies and signs / symptoms of the three nursing diagnoses in clinical case studies with the results of the content validity. This study was a descriptive study. The sample consisted of 23 experts (professors, head nurses and clinical instructors) who had had a variety of experiences using nursing diagnoses in clinical practice, and 102 case reports done by senior student nurses of the college of nursing of Y-university. These reports were part of their clinical practice in the ICU. The instrument used for this study was a checklist for etiologies and signs and symptoms based on the literature, Doenges and Moorhouse (1988), Kim, McFarland, McLane (1991), Lee Won Hee et al. (1987), Kim Cho Ja et at. (1988). The data was collected over four month period from May 1992 to Aug. 1992. Data were analyzed using frequencies done with the SPSS / PC+ package. The results of this study are summarized as follows : 1. General Characteristics of the Expert Group A bachelor degree was held by 43.5% and a master or doctoral degree by 56.5% of the expert group. The average age of the expert group was 35.3 years. Their average clinical experience was 9.3 years and their average experience in clinical practice was 5.9 years. The general characteristics of the patients showed that there were more women than men, that the age range was from 1 to over 80. Most of their medical diagnoses were diagnoses related to the respiratory. system, circulation or neurologic system, and 50% or more of them had a ventilator with intubation or a tracheostomy. The number of cases for each nursing diagnoses was : · Ineffective airway clearance, 92 cases. · Ineffective breathing pattern, 18 cases. · Impaired gas exchange, 22 cases. 2. The opinion of the expert group as to the classification of the etiology, and signs and symptoms of the three nursing diagnoses was as follows : · In 31.8% of the cases the classification of etiology was clear. · In 22.7%, the classification of signs and symptoms was clear. · In 17.4%, the classification of nursing interventions was clear. 3. In the expert group 80% or mere agreed to ‘dysp-nea’as a common sign and symptom of the three nursing diagnoses. The distinguishing signs and symptoms of (Ineffective airway clearance) were ‘sputum’, ‘cough’, ‘abnormal respiratory sounds : rales’. The distinguishing sings and symptoms of (Ineffective breathing pattern) were ‘tachypnea’, ‘use of accessory muscle of respiration’, ‘orthopnea’ and for (Impaired gas exchange) it was ‘abnormal arterial blood gas’, 4. The distribution of etiology, and signs and symptoms of the three nursing diagnoses was as follows : · There was a high frequency of ‘increased secretion from the bronchus and trachea’ in both the expert group and the case reports as the etiology of ineffective airway clearance. · For the etiologies for ineffective breathing pat-tern, ‘rain’, ‘anxiety’, ‘fear’, ‘obstructions of the tract, ca and bronchus’ had a high ratio in the ex-pert group and ‘decreased expansion of lung’ in the case reports. · For the etiologies for impaired gas exchanges, ‘altered oxygen -carrying capacity of the blood’ and ‘excess accumulation of interstitial fluid in lung’ had a high ratio in the expert group and ‘altered oxygen supply’ in the case reports. · For signs and symptoms for ineffective airway clearance, ‘dyspnea’, ‘altered amount and character of sputum’ were included by 100% of the expert group. ‘Abnormal respiratory. sound(rate, rhonchi)’ were included by a high ratio of the expert group. · For the signs and symptoms for ineffective breathing pattern. ‘dyspnea’, ‘shortness of breath’ were included by 100% of the expert group. In the case reports, ‘dyspnea’ and ‘tachypnea’ were reported as signs and symptoms. · For the sign and symptoms for impaired gas exchange, ‘hypoxia’ and ‘cyanosis’ had a high ratio in the expert group. In the case report, ‘hypercapnia’, ‘hypoxia’ and ‘inability to remove secretions’ were reported as signs and symptoms. In summary, the similarity of the etiologies and signs and symptoms of the three nursing diagnoses related to difficulty in respiratory function makes it difficult to distinguish among them But the clinical validity of three nursing diagnoses was established through this study, and at last one sign and symp-tom was defined for each diagnosis.
입지조건(立地條件)이 다른 산간도시(山間都市)인 춘천(春川)과 교차교통(交叉交通) Center인 평탄지(平坦地) 도시대전(都市大田) 및 수도(首都)의 관문(關門)이며 산업도시(産業都市)인 인천(仁川)을 대상(對象)으로 지역조건(地域條件)이 낙농경영발전(酪農經營發展)에 어떻게 영향(影響)을 주었는가를 비교조사(比較調査)했다. 그 결과(結果)는 다음과 같다. 1) 인천시(仁川市)와 같은 우유생산물(生産物) 수요(需要)가 크고 넓은 시장지역(市場地域)이 경영발전(經營發展)에 가장 영향(影響)이 컸다. 그러나 토지이용면(土地利用面)에서 조사료(粗飼料)의 기반(基盤)이 약(弱)한 것이 가장 큰 문제(問題)가 된다. 2) 산간지(山間地) 낙농(酪農)의 대표적종류(代表的種類)인 춘천(春川)은 낙농가(酪農家)의 92%가 양계(養鷄)와의 겸업(兼業)이 충분(充分)한 토지(土地)를 소유(所有)하고도 초지이용율(草地利用率)이 원활(圓滑)하지 못했다. 3) 대전(大田)의 평탄낙농경영(平坦酪農經營)은 현재(現在)는 겸업(兼業)으로서 합리적(合理的) 경영(經營)을 기도(企圖)하고 있으나 토지이용상(土地利用上) 과수원(果樹園)과의 경합(競合)이 문제점(問題點)이 될 우려가 크다. 4) 노임수준(勞賃水準)의 격차(格差)는 지역간(地域間)에 큰 차(差)가 없다. 5) 노동공급량(勞動供給量)은 인천(仁川)이 가장 많고 산간(山間)이 오히려 타농업부문(他農業部門)과의 경합(競合)이 있었다. 가족노동력(家族勞動力)은 기능화(技能化)됐고 상용고용인(常用雇傭人)도 경력(經歷)에 따라 기능화(技能化)되어 있지만 그 차(差)가 심하며 직장유동(職場流動)이 심(甚)하다. 6) 대전(大田) 춘천(春川) 같은 겸업지대(兼業地帶)에서는 타종(他種)과의 노동배분(勞動配分)이 확연(確然)하지 않고 따라서 노동(勞動)의 직능분화(職能分化)가 늦으며 잡역부(雜役夫)가 많다. 7) 특(特)히 생산자(生産者) 유가(乳價)는 지역간(地域間)에 차(差)가 있고 이것은 수익상(收益上) 막대(莫大)한 영향(影響)을 주고 있다. 춘천(春川)의 낙농(酪農) 발전저해요인중(發展沮害要因中) 가장 큰 문제중(問題中) 하나이다.
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70