• 한국안전학회지
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• 제5권3호
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• pp.3-7
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• 1990

This study is conducted to experiment on the performance test for 20 types of Filter-integrated Half-masks which could not only protect workers exposed to dusty environment, but also improve workability. Results and conclusions are as follows ： 1) Respirators that removal efficiency of aerosols is 95 percent or more are 11 kinds(55%), and those who are 99.9 percent or more are 4 kinds(20%). Respirators that inhalation resistance is 4 mm in water or less are 13 kinds(65%), and those who are 6 mm in water or less are 17 kinds(85%). Respirators that efficiency of cumulative inhalation resistance is 100 percent or less are 11 kinds(55%) . 2) Respirators that resistance of moisture inhalation is 6 mm in water or less are 11 kinds(55%). and those who are 10 mm in water or less are 13 kinds(65cio), Respira'tors that ratio of removal efficiency for aerosols between dry and wet conditions is 95 percent or more are 9 kinds(45%). 3) Respirators which are not only 95 percent or more for removal efficiency of aersosls and 6 mm in water or less for inhalation resistance, but also 200 percent or less for efficiency of cumulative inhalation resistance, are 8 kinds(40％). Respirators which are not only 99.9 percent or more for removal efficiency and 6 mm in water or less for inhalation resistance, but also 100 percent or less for efficiency of cumulative inhalation resistance, are 3 kinds(15%). Respirators which are not only 95 percent or more for removal efficiency of aerosols and 6 mm in water or less for inhalation resistance, but also 200 percent or less for efficiency of cumulative inhalation resistance and 10 mm in water or less for resistance of moisture inhalation, are 6 kinds(30％) . 4) As standard rrlodel of artificial human head which would be perhaps different from the true one Is used to experiment fitness test, leakage rate is shown to be more or less high. However, artificial human head shall be accurately examined and follow-up studt. would be conducted in the future.

• Journal of Korean Dental Science
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• 제3권1호
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• pp.11-16
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• 2010

Objective : This prospective study sought to verify the stability of three types of short implants measuring 7mm or less. Materials and methods : Implants measuring 7mm or less were placed in patients at multicenter dental clinics in Korea, China, Taiwan, and Singapore. Initial stability, intraoperative and postoperative complications, crestal bone loss, and survival rate of the implant were prospectively evaluated. Results : The primary stability of a 6-mm implant was lower than that of a 7-mm implant. The marginal bone loss of short implants measuring less than 7mm was minimal. Complications such as wound dehiscence, implant mobility, and peri-implant mucositis developed, and these were associated with initial implant failure. The short-term survival rate of 6-mm implant was 93.7%, and that of 7-mm implant, 96.6%. Conclusion : Short implant for the mandible with insufficient height for the residual ridge can be selectively used. Poor primary stability and wound dehiscence can cause osseointegration failure and alveolar bone loss.

• Journal of Korean Neurosurgical Society
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• 제45권2호
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• pp.85-89
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• 2009

Objective : The International Study of Unruptured Intracranial Aneurysms (ISUIA) reported that the 5-year cumulative rupture rate of small unruptured aneurysms less than 7 mm in diameter is very low depending on the aneurysm's location. However, we have seen a large number of ruptured aneurysms less than 7 mm in clinical practice. The purpose of this study was to review our experience and to measure the size and location at which aneurysms ruptured in our patient population. Methods : We reviewed the characteristics of aneurysms, such as size and location, from the original angiograms of patients who were admitted to our hospital between January 2004 and December 2007. All aneurysms were treated surgically or through endovascular procedures. Results : Interventional or surgical treatment was given to a total of 889 patients, including 568 females and 321 males. At the time of our study, 627 cases were ruptured aneurysms and 262 cases were unruptured aneurysms. Of the ruptured cases, the mean diameter of the aneurysm was 6.28 mm. We found that 71.8% of ruptured aneurysms were smaller than 7 mm in diameter, and 87.9%, were smaller than 10 mm. Based on location, the data show that anterior communicating artery aneurysms most often presented with rupture sizes less than 7 mm (76.8%) and 10 mm (92.1%) in diameter. Most ruptured aneurysms were less than 7 mm in size, although recent studies have noted that small aneurysms are less likely to rupture. Conclusion : Although the natural history of unruptured intracranial aneurysms remains controversial, the aneurysm size and location play a signigicant role in determining the risk of rupture. Larger sample sizes and a long term study are needed to reveal the natural history and the rupture risk of unruptured intracranial aneurysms because the size of most ruptured aneurysms was less than 7 mm in diameter in our series.

• 한국광학회지
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• 제5권2호
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• pp.204-211
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• 1994

팩시밀이나 복사기용으로 이용되는 micro lens array를 설계하였다. array 형태는 육각형배열이고 유효경은 0.160mm, 가장 가까운 이웃렌즈의 중심간 거리는 0.192mm로 하였다. 결상계의 횡배율은 1.0이다. single layer는 working distance가 10.55mm, double layer는 working distance가 7.90mm가 되었다. 각각의 성능은 ray fan을 계산하여 그 특성을 조사하였으며 서로 비교하였다.

• 대한두개안면성형외과학회지
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• 제15권1호
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• pp.1-6
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• 2014

Background: The ear is composed of elastic cartilage as its framework, and is covered with a thin layer of skin. Auricular reconstruction using autogenous cartilage in microtia patients requires delicacy. This paper reports clinical experiences related to elevation of reconstructed ear in the last 11 years. Methods: This study was based on 68 congenital microtia patients who underwent auricular elevation in our hospital. Among these 68 patients, 47 patients were recruited. We compared the differences in the ear size, auriculocephalic angle, and conchal depth with those in the opposite ear, and the patients' satisfaction levels were investigated using a survey. Results: The difference in the sizes of the two ears was less than or equal to 5 mm in 32 patients, 5 to 10 mm in 10 patients, and greater than or equal to 10 mm in 5 patients. The difference in the auriculocephalic angles of the two ears was less than or equal to 10 degrees in 14 patients, 10 to 20 degrees in 26 patients, and greater than or equal to 20 degrees in 7 patients. The difference in the conchal depths of the two ears was less than or equal to 5 mm in 24 patients, 5 to 10 mm in 19 patients, and greater than or equal to 10 mm in 4 patients. The average grade of 3.9 points out of 5 points was obtained by the patients with satisfactory surveys. Conclusion: We could make enough protrusion and maintain the three-dimensional shape for a long time to satisfy our patients.

• 한국물환경학회지
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• 제39권1호
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• pp.30-37
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• 2023

This study aimed to evaluate the ability to reduce flood damage caused by abnormal rainfall events due to climate change by utilizing a blue-green roof (BGF), a type of rooftop greening technology. For two buildings with the same roof area, a BGF was installed in the experimental group, a general roof was configured in the control group, and rainfall runoff was compared. A total of 10 rainfall events were tested and analyzed by classifying them into three rainfall classes (less than 10 mm, less than 100 mm, and more than 100 mm). There was a reduction of 100% in the case of 10 mm or less of rainfall, 84. 7% in the case of 100 mm or less, and 39.8% in the case of 100 mm or more. Although this study showed that a BGF was effective in reducing rainfall runoff, additional experiments and analyses of various factors affecting rainfall runoff reduction are needed to generalize the results of the study. This research methodology may be used to develop a method for evaluating the resilience of a BGF to flood damage due to climate change.

• 소성∙가공
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• 제5권2호
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• pp.115-121
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• 1996

Recently it is attempted to manufacture gears by various cold forging methods to meet requirements of mass production and uniform qualities. Compared to machined gears cold forged ears reveal higher tooth strength and better surface roughness but they reveal lower geometrical accuracies. Therefore in the present study a series of experiments are performed to investigate relations between geometrical accuracies of dies and billet and those of the final product. The geometrical accuracies of forged gears are considered through functional gear-element tolerances by measuring pitch error profile error lead error radial error tooth thickness and rolling test. Results of the experiments can be summarized as follows: (1) involute spur gears of KS 5(or AGMA7) accuracies can be made,(2) concentricity of die set should be maintained within 0.01mm (3) clearance between the billet and die set should be less than 0.1mm (4) con-centricity and radial runout should be less than 0.08mm and 0.1mm respectively. However it is thought that FEM analysis of elastic/thermal deformations of dies and the billet is necessary for a better understanding of the findings obtained through the present study.

• Radiation Oncology Journal
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• 제18권2호
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• pp.127-132
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• 2000

목적 : 두경부 악성 림파절 환자에서 방사선치료중 종양내 간질액 압력을 측정하여 종양내 간질액 압력 및 이의 변화가 갖는 임상적 의의를 밝히고자 하였다. 방법 : 조직학적으로 확진된 26명의 전이성 두경부 악성 림파절 환자를 대상으로 육안적으로 확인 가능하며 접근이 가능한 부위에 위치하고 주사침 끝이 적절히 위치할 수 있도록 적어도 1 cm 이상의 충분한 두께를 갖는 경부 림프절에서 방사선치료 직전 및 방사선치료 중에 종양내 간질액 압력을 측정하였다. 종양의 크기는 촉지하여 임상적으로 측정하고 방사선과적 검사로 측정을 확인하였다. 결과 : 방사선치료 전 TIFP는 25명에서 측정이 가능하였으며 평균치는 24.7 mmHg였다. 방사선치료 전종양의 크기가 클수록 치료 전 TIFP가 높았으며 통계적으로 marginal한 상관관계를 보였고(p=0.06), 치료 전 종양 크기가 크면 치료 후 TIFP의 감소가 큰 경향을 보였으나 통계적인 유의성은 없었다(p=0.43). 방사선치료 중 9명에서 TIFP의 측정이 가능하였으며, 이들의 방사선치료 전과 치료 후 TIFP변화는 평균 12.5 mmHg로 감소하였으며 통계적으로 유의한 결과를 보였다(p=0.009). 치료 전 TIFP가 평균치 이상인 환자군과 이하인 환자군 사이에 방사선치료 결과의 차이가 관찰되지 않았다(p=0.229). 방사선 치료 후 완전 관해를 보인 환자군과 부분관해 이하의 치료 결과를 보인 군 사이에 치료 전 TIFP의 차이는 관찰되지 않았다(p=0.75). 방사선치료 후 완전 관해를 보인 환자군의 TIFP의 치료 전과 치료 중 비교시 평균 36 mmHg 감소하였으며 부분관해 이하의 치료 결과를 보인 군은 29.7 mmHg 감소하여 현재까지는 두 환자군 사이에 유의한 차이는 관찰되지 않았다(p=0.75) 결론 : 방사선치료 전 TIFP의 평균치는 24.7 mmHg였으며 종양의 크기가 클수록 치료 전 TIFP가 높았으며 통계적으로 marginal하게 유의하였다(p=0.06). 방사선치료 후 부분 관해 이하의 치료 결과를 보인 환자군의 치료 전과 치료 중 TIFP를 비교시 평균 29.7 mmHg로 감소하였으나 완전관해를 보인 군은 36mmHg의 더 큰 감소를 보였으나 현재까지는 두 군간의 차이는 유의하지는 않았다.(p=0.75)

• 보험의학회지
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• 제9권
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• pp.122-129
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• 1990

Authors analyzed sonographic findings of 59 cases of hepatic hemangioma, with had been diagnosed through examination in our Medical. dept, from Januray, 1985 to December 1989. The results of the analysis are as follows: 1) The hepatic hemangioma was found in 59 cases(0.33%) among the 17,714 insureds. 2) In all 59 cases who have hemangioma, hemangioma was found in 37 cases(0.35%) among the 10,724 insureds of male, and in 22 cases(0.31%) among the 6,990 insureds of female. 3) The possessing rate of hemangioma in male was increased by age regardless of sex-5/2,120 cases(0.24%) in $21{\sim}30$ years, 25/8,122 cases(0.31%) in $31{\sim}40$ years, 16/4,997 cases(0.32%) in $41{\sim}50$ years, 8/1,775 cases(0.45%) in $51{\sim}60$ years, and 5/359 cases(1.39%) in over 61 years. 4) The tumor involved right lobe of the liver in majority(71.4%) 5) The size of tumor was 10 lesions in under 10 mm, 58 lesions in $31{\sim}50$ mm, and 6 lesions in over 51 mm. The smallest tumor was 8 mm in diameter and the largest was 72 mm in diameter and 78 lesion(92.8%) were less than 50 mm in size. 6) Posterior acoustic enhancement was noted in 4 lesions among 68 lesions of less than 30 mm in long diameter, and in 4 lesions among 16 lesions more than 30 mm in long diameter. 7) Echographically most of the lesions presented as a round or oval high homogeneous echogenic mass, although a few mass appeared to be hypoechoic or Mixed echogenic. Finally a small round echogenic, sharply-marginated and internally homogeneous lesion is highly suggestive of hemangioma. If the hypoechoic lesion has homogeneous internal echoes and/or strong marginal echoes, it is also suggestive of hemangioma.

• ETRI Journal
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• 제44권6호
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• pp.1020-1033
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• 2022

In this paper, we propose novel disaggregated memory module (dMM) architecture and memory access control schemes to solve the collision and contention problems of memory disaggregation, reducing the average memory access time to less than 1 ㎲. In the schemes, the distributed scheduler in each dMM determines the order of memory read/write access based on delay-sensitive priority requests in the disaggregated memory access frame (dMAF). We used the memory-intensive first (MIF) algorithm and priority-based MIF (p-MIF) algorithm that prioritize delay-sensitive and/or memory-intensive (MI) traffic over CPU-intensive (CI) traffic. We evaluated the performance of the proposed schemes through simulation using OPNET and hardware implementation. Our results showed that when the offered load was below 0.7 and the payload of dMAF was 256 bytes, the average round trip time (RTT) was the lowest, ~0.676 ㎲. The dMM scheduling algorithms, MIF and p-MIF, achieved delay less than 1 ㎲ for all MI traffic with less than 10% of transmission overhead.