• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.95-110
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• 1992

Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

• Journal of Chest Surgery
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• v.23 no.4
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• pp.617-621
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• 1990

A heart supplies blood of about 15, 000 liters to each human organ in a day. A normal function of heart valves is necessary to accomplish these enormous work of heart. The disease of heart valve develops to a narrowness of a closure, resulting in an abnormal circulation of blood. In an attempt to eliminate the affliction of heart valves, the operative method to replace with artificial heart valves has developed and saved numerous patients over past 30 years. This replacement operation has been performed since early 1960`s in Korea, but all the artificial heart valves used are imported from abroad with very high costs until recent years. New artificial heart valves have been developed in Korea Advanced Institute of Science and Technology since early 1980`s. The first developed valve was designed with a free-floating pyrolytic carbon disk that is suspended in a titanium cage. The design of the valve was tested in vitro, and in animals in 1987. The results from this study was that the eccentrically placed struts creates a major and minor orifice when the disc opens and stagnation of flow in the area of the minor orifice has led to valve thrombosis. In this work, the design of the valve was changed from a single - leaflet valve to double - leaflet one in order to resolve the problems observed in the first - year tests. Morphological and hemodynamic studies were made for the newly designed valves through the in vitro and in vivo tests. The design and partial materials of the artificial heart valve was improved comparing with first - year`s model. The disc in the valve was modified from single - leaflet to bi - leaflet, and the material of the cage was changed from titanium metal to silicon - alloyed pyrolytic carbon. A test was made for the valve in order to examine its mechanical performance and stability. Morphological and hemodynamic studies were made for the valve that had been implanted in tricuspid position of mongrel dogs. All the test animals were observed just before the deaths. A new artificial heart valve was designed and fabricated in order to resolve the problems observed in the old model. The new valve was verified to have good stability and high resistance to wear through the performance tests. The hemodynamic properties of the valve after implantation were also estimated to be good in animal tests. Therefore, the results suggest that the newly designed valve in this work has a good quality in view of the biocompatibility. However, valve thrombosis on valve leaflets and annulus were found. This morphological findings were in accordance with results of surface polishing status studies, indicating that a technique of fine polishing of the surface is necessary to develop a valve with higher quality and performance.

• Journal of Chest Surgery
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• v.22 no.1
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• pp.134-140
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• 1989

A clinical evaluation was made on total 207 cases of corrosive esophageal stricture after ingestion of various corrosive substances and 173 cases of neoplasms in the esophagus and the cardia. The various complications associated with esophageal corrosion were observed on 28 cases [13.5%] in a total of 207 cases. Pathoanatomic findings of complication may be classified to the five category as follow; [1] stenosis in the pharynx due to adhesion of the epiglottis, [2] esophagobronchial fistula, [3] esophageal perforation with bougienation, [4] necrotic rupture of the esophagus and the stomach, and [5] so-called chronic corrosive gastritis. The comparative studies were done on a total of 165 cases of the various procedures of esophagoplasty to the reconstruction of the esophagus, which consists of antethoracal esophagoplasty with jejunum, retrosternal esophagoplasty with jejunum, retrosternal esophagoplasty with right colon, and retrosternal esophagoplasty with left colon. There is no hard and fast rule in selection of jejunum, right colon or left colon as the transplanting bowel and an operative method either antethoracal or retrosternal approach. When there was no possibility of the complication and no any defect of the anatomical states, one stage retrosternal esophagoplasty using right colon was better in various points of view. The 173 patients of the neoplasm of the esophagus consist of 28 cases of benign tumors and 145 cases of malignant tumors in the esophagus and cardia. 28 cases of benign tumors in the esophagus received the surgical treatment and they obtained with excellent results postoperatively. Of the 145 patients of esophageal carcinoma who received surgical managements, 101 cases [69.6%] were found to be operable and 44 cases [30.3%] were inoperable. Due to the various level of carcinoma in the esophagus, the following different surgical procedure was properly used case by case to get the best results in each case. Esophageal carcinoma in the upper and middle third segment received the total esophagectomy and the reconstruction of the esophagus using right colon by substernal procedure. Esophageal carcinoma in the lower third segment received an esophagojejunostomy in the mediastinum after the resection of lower third segment of the esophagus. Carcinoma in the esophago cardia and the stomach received also an esophagojejunostomy after the resection of the lower third segment of the esophagus and subtotal gastrectomy. For the 44 patients with inoperable carcinoma, the several palliative surgical managements such as gastrostomy or jejunostomy for feeding and esophagojejunostomy for bypass of the lower esophagus and the stomach were properly performed case by case for their maximum improvement.

• Journal of Chest Surgery
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• v.33 no.6
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• pp.494-501
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• 2000

Background: Transmyocardial laser revascularization(TMLR) for revascularizing ischemic myocardium in patients was originally based on the assumption that laser channels remain their patency much longer. But recent studies show that laser channels did not remain open and that TMLR could achieve treatment benefits without long-term channel patency. The angiongencesis is currently thought to be induced by non-specific inflammatory response to mechanical tissue injury. This study is to evaluate hypothesis that various transmyocaridal mechanical revascularization(TMMR) may induce the angiogenic responses similar to that seen with TMLR, and transmyocaridal polymer stent revascularization(TMSR), the polymer stent in the myocardial tissue is hydrolyzed in 2 weeks, may enhance the non-specific inflammatory reaction resulting angiogenesis. Furthermore, polymer myocaridal stent channels remain long-term patency. Material and Method: Eight domestic pigs underwent ligation of the proximal circumflex artery, and 2 weeks later they were randomized to undergo transmycardial acupunctural revascularization (TMPR, Group I) of the left lateral wall with 18-G needle(n=2), to undergo transmyocardial (TMDR, Group II) with industrial 2mm steel drill(n=2), to undergo transmyocardial polymer stent revascularization (TMSR, Group III) after drilling the infarcted myocardium(n=2), the stent is poly(lactic acid-co-glycolic acid), which is self-degradated in the myocardium, and to a control group the ischemic zone was unterated(n=2). All the pigs were sacrificed after 4 weeks TMMR. Sections from the ischemic zone were submitted for vascular endothelial growth factor (VEGF) ELISA and histology. Result: There were makedly increase in the VEGF immunoassay in the ischemic zone of the TMMR group compared to the ischemic zone of the control group(control: each 30.85 and 43.15pg/mg protein, TMPR: each 44.14 and 68.61 pg/mg protein, TMDR: each 65.92 and 78.65 pg/mg protein, TMSR: each 177.39 and 168.87 pg/mg protein). TMSR channels caused greatest VEGF expression than channels made by other group and the polymer stent channels remained vacuole after 4 weeks. Conclusion: Transmyocardial polymer stent revascularization promoted the most angiogenci response by the VEGF immunoassay, although our study did not show the statistical significancy. The channels remained but the flow patency was not verified. Transmyocardial polymer stent revascularization (TMSR) is desirable in future experimental trials and in view of the significant cost implications comparable to that of laser.

• Journal of Chest Surgery
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• v.33 no.3
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• pp.231-239
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• 2000

Background: This retrospective study tries to identify specific risk factors that may increase complication rates after the surgical treatment of tuberculous destroyed lung. Material and method: A retrospective study was performed on forty-seven patients, who received surgical treatment for tuberculous destroyed lung in the Department of Thoracic and Cardiovascular Surgery at Hanyang University Hospital from 1988 to 1998, to identify specific preoperative risk factors related to postoperative complications. Fisher's exact test was used to identify the correlations between the complications and right pneumonectomy, preoperative FEV1, predicted postoperative FEV1, massive hemoptysis, postoperative persistent empyema. Result: Hospital mortality and morbidity rates of the patients who received surgical treatment for tuberculous destroyed lung were 6.4% and 29.7%, respectively. In view of the hospital mortality and morbidity rates as a whole, predicted postoperative FEV1 less than 0.8L(p<0.005), preoperative FEV1 less than 1.8L(p=0.01), massive hemoptysis(p<0.005), postoperative persistent positive sputum cultures(p<0.0005), and the presence of multi drug resistant tuberculosis(p<0.05) presented statistically significant correlations. Among the postoperative complications, bronchopleural fistula, the most common complication, was found to have statistically significant corrleations with the preoperative empyema(p<0.05) and postoperative persistent positive sputum cultures(p<0.05). Conclusion: Although mortality and morbidity rates after surgical treatment of tuberculous destroyed lung were relatively low, when predicted postoperative FEV1 was less than 0.8L, when preoperative FEV1 was less than 1.8L, when massive hemoptysis was present, when postoperative sputum cultures were persistently positive, and when multi drug resistant tuberculosis was present, the rates were significantly higher.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.281-289
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• 2000

Background : Mycobacterial culture is a confirmatory test to detect. M. tuberculosis, but it takes at least 6 weeks to diagnose. PCR is a rapid and sensitive method, but it is known that PCR has a high false positive rate due to contamination, and a high false negative rate due to inhibitors. It is also known that LCR and PCR-Hybridization, recently developed methods, are more specific methods than PCR in terms of detecting M. tuberculosis. In this study, we estimated the clinical utility of in house PCR, LCR and PCR-Hybridization for the detection of M. tuberculosis. Methods : We evaluated 75 specimens, upon which M. tuberculosis culture based testing was requested, by PCR LCR, and PCR-Hybridization and compared results. Mycobacterial culture was performed on 3% Ogawa media for 8 weeks, and an in house PCR, LCx Mycobacterium tuberculosis assay kit (Abbott Laboratories, North Chicago, III) and the AMPLICOR M. tuberculosis test kit (Roche Molecular Systems, Inc. Branchburg, NJ. USA). Results : In the view of the culture results, the sensitivities of the three tests were 40%, 80%, and 100% and their specificities were 98.6%, 94.3%, and 94.3%. Conclusion : LCR and PCR-Hybridization are rapid and sensitive methods for detecting M. tuberculosis in clinical laboratories.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.3
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• pp.522-531
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• 1999

This research identifies the ingress to egress primary factors that causes a patient to receive delayed emergency medical care. This material was collected between February 1st to 28th, 1998. Research envolved 4,118 people who visited the college emergency medical center in Kyeongido Province, South Korea. Medical records were examined, using the retrospective method. to determine the length of stay and the main cause for waiting. Results are as follows : 1. The age group with the highest admission rate was 10 and under, approximately 1,394 (33.9%). Followed by an even distribution for ages between 11-50 at 10-15% for their respective ranges. The lowest admission rate was 50 years and above. 2. From the 4,118 records examined, 3,489 received outpatient treatment (84.7%); 601 were admitted for inpatient care (14.6%); 25 arrived dead on arrival (0.6%); and 4 people died at the hospital. 3. Between 7PM to 12AM, 42.9% were admitted to the EMC. The hours from 9PM to 11PM recorded the highest admission rate and 5AM to 8AM was the lowest From 8PM to 12AM, the most beds were occupied. 4. For most patients. the average length of stay was approximately 2.2 hours. By medical department, external medicine was the longest for 2.8 hours. Pediatrics was the shortest for 1.6 hours. The average waiting period for inpatient admission was 2.6 hours. Inpatient admission for pediatrics and external medicine was 3.4 hours and 2.2 hours respectively. 5. Theses are primary factors for delay at EMC: 1) pronged medical consultations to decide between inpatient versus outpatient treatment, and delaying to be inpatient, 2) when you call physicians they are delayed to come 3) Understaffing during peak or critical hours, 4) Excessive consulting with different medical departments, 5) some patients require longer monitoring periods, 6) medical records are delayed in transit between departments, 7) repeated laboratory tests make delay the result, 8) overcrowded emergency x-ray place causes delay taking x-ray and portable x-ray, 9) the distance between EMC and registration and cashier offices is too far. 10) hard to control patient's family members. The best way to reduce EMC waiting and staying time is by cooperation between departments, both medical and administrative. Each department must work beyond their job description or duty and help each other to provide the best medical service and satisfy the patient needs. The most important answer to shortened the EMC point from ingress to egress is to see things from a patient point of view and begin from there to find the solution.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.136-143
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• 2013

In this paper, a algorithm to find joints of a small animal like a lizard from the multiple-view silhouette images is presented. The proposed algorithm is able to calculate the 3D coordinates so that the locomotion of the lizard is markerlessly reconstructed. The silhouette images of the lizard was obtained by a adaptive threshold algorithm. The skeleton image of the silhouette image was obtained by Zhang-Suen method. The back-bone line, head and tail point were detected with the A* search algorithm and the elimination of the ortho-diagonal connection algorithm. Shoulder joints and hip joints of a lizard were found by $3{\times}3$ masking of the thicked back-bone line. Foot points were obtained by morphology calculation. Finally elbow and knee joint were calculated by the ortho distance from the lines of foot points and shoulder/hip joint. The performance of the suggested algorithm was evaluated through the experiment of detecting joints of a small lizard.

• Journal of the HCI Society of Korea
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• v.1 no.1
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• pp.81-88
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• 2006

With the introduction of the digital technology in the exhibition environment, the information of the exhibit has come to be transmitted through diverse media. The visitors desire has been increased from the simple viewing of the exhibition to the active participation in the exhibition viewing and the utilization of the exhibit information. Subsequently, the study on the service to effectively support the viewing experience and provide the information by utilizing the internet and mobile device for visitors in movement has become important in terms of the exhibition environment. Accordingly, in this study, the current condition in studying the service supporting the exhibition environment and the exhibition viewing, which are being changed into a digital network environment, was examined through the literature and case studies. In order to find out the viewing situation and viewing type of visitors, the visitors behaviors of viewing the exhibition were observed. By analyzing the contents observed, the viewing type and keyword were drawn in accordance with the visitors behaviors of viewing. On the basis of this, visitors needs and problems occurring in case of the exhibition viewing were found out via in-depth interview. The service factors of supporting the exhibition viewing were proposed on the basis of the factors by which visitors needs and problems could be solved via interface in the circumstance when visitors would move round the exhibition hall and view the exhibition. In terms of the service factors, the method to resolve was presented on the basis of the relationship between the exhibit and the space in case of selecting and viewing the exhibit. This was applied into the mobile PDA with the example of the exhibition environment in the national museum. Through the scenario of using, the usefulness of the service proposed and the relevant possibility of utilization were reviewed.

• Journal of Korean Home Economics Education Association
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• v.17 no.4 s.38
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• pp.55-71
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• 2005

This study attempts to analyze research Quality about home economics and education, based on the studies in the Journal of Korean Home Ecomics Education. The purpose of this study is to investigate the recent studies in hem economics and find out the desirable direction of it. The findings of study are as follow: While the numbers of articles appeared in The Korea Association of Practical Arts Education and Korean Home Economics Education Association are increasing, The Korean Home economics Association does not show the increase the number of articles. According to the historical changes and distribution, the majority was teaching-learning method and teaching materials. Also, from the point of view in research thesis, there were more articles in home economics and education than any others, In addition, among the various types of research, survey was most frequently used. There was significant differences of the sizes of groups according to the different journals, but the one group research was most frequent and one certain research area was dominant. The teams consist of two people showed the highest ratio, and junior high and high school were the most frequently researched institutions. Generally, it is hard to find research grant. Though there is much difference in numbers of references based upon various journals, almost all articles cited reference date not only from Korean articles, but also from international articles.