• Journal of the Korean Society for Precision Engineering
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• v.16 no.8
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• pp.203-212
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• 1999

This paper describes a deadweight force standard machine with the weight change mechanism which can be used as a primary force standards at a national metrology institute. Since commercial deadweight force machine can generate forces by hanging weights to the weight supporter serially, force steps from deadweight force measuring devices of each having different capacity. In order to increase the force steps, we have specially designed a weight mechanism in which the machine can select the necessary weights and generate the load by hanging the selected weights to the weight supporter. The machine can generate 속 force of the range of 2 kN to 110 kN with force step of 1 kN. All weights have been accurately compensated and calibrated by a mass comparator and its standard uncertainty is less than 2.2 ${\times}\;10^{-6}$. The relative expanded uncertainty of the machine is 1.3 ${\times}\;10^{-5}$.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.563-568
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• 2008

The Green Building Certification is issued through self-assessment of applicant, assessment of assessment members and deliberation committee members. These assessments are carried out based on a standard provided Ministry of land transport and maritime affairs and environment. However, opinion difference of assessment standards could be occurred due to diversity of understanding for a standard or subjectivity of committee member. In this paper, We discussed the primary cause of score difference after analyzed assessment standard for the site, transportation, energy and resources, ecological environment, indoor environment in five different Apartment Houses located in Seoul. At a result, score difference was at least 3 points in each section except indoor environment and total score difference of housing complex is by 10 points. To improve these problems, educational program should be activated and guide for assessment standard should be published.

• Journal of Navigation and Port Research
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• v.31 no.4
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• pp.281-287
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• 2007

Human factors have been considered the primary reason of marine accidents. Especially, the collision between vessels is mostly mused by human behavior. However, there have not been many researches to clarify the reason of marine accidents mused by human factors quantitatively. In order to understand human factors and to enhance safe navigation systematically, using a full mission ship-handling simulator, we've investigated the characteristics of avoiding behavior taken by mariners. Further in order to apply the characteristics more widely and effectively, it's necessary to formulate the standard behavior for ship-handling in the condition of collision avoidance. Is this study, therefore, we intended to propose the concept to model the mariner's standard behavior on the handling of collision avoidance as the first step. As a result, we confirmed the contents of information processing in ship-handling that mariner's generally taking to avoid collision.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2698-2703
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• 2024

A bilateral comparison was conducted between the International Atomic Energy Agency (IAEA) and the Korea Research Institute of Standards and Science (KRISS) to measure the absorbed dose to water in accelerator photon beams. KRISS served as a linking laboratory to compare the IAEA standard with the key comparison reference value (KCRV) of the BIPM.RI(I)-K6 program, in which KRISS participated in 2017. Two ionization chambers from the IAEA were used as transfer instruments for the comparison. Both laboratories measured the calibration coefficients of these instruments and calculated the ratios. The ratio of the KRISS standard to the KCRV was applied to obtain the degree of equivalence of the IAEA, along with its uncertainty. The largest deviation of the IAEA measurement from the KCRV was 3.4 mGy/Gy, significantly smaller than the expanded uncertainty of 10.7 mGy/Gy (k = 2, 95% level of confidence). This study demonstrates the equivalence of IAEA's measurement standard for accelerator photon beams to other primary standard dosimetry laboratories. It provides evidence for the satisfactory operation of IAEA's quality management system and enhances the international credibility of the IAEA SSDL network, particularly in high-energy accelerator photon beams from linear accelerators.

• Journal of the Korean Institute of Educational Facilities
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• v.19 no.3
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• pp.21-31
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• 2012

According to the decrease in birth rate and reduction of population in rural area, primary schools have brought about many problems for decrease of number of student, and environment of education have became deteriorated. Accordingly, primary schools be required improvement, and it should be altered placement of schools because it change number of student, distance and time of attending school, and formation of school zone are changed by alternating of human and physical environment. Merger and abolition of primary school is inevitable for change of placement standard to primary school and qualitative improvement of environment of education in rural area. This study suggests the effective space planning methods for unified school and appropriate utilization alternatives for closed school following after the merger and abolition of small rural schools. In doing so, it explores the present models of merger and abolition through analysis of all sort of actual condition and the possibilities for various utilizations of the abolished schools. It proposes a classroom-operation type fused the comprehensive class and departmental class system for merged primary schools in rural area. It also suggests the re-use methods of closed school facilities for students and community. Finally, it emphasizes that in order to success the policy of the merger and abolition of small schools, it be attributed to the social-cultural environment based on local residents and community and required provision of a variety of utilization plans reflecting local specifics and guarantee of local residents' participation and selection.

• Journal of Chest Surgery
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• v.49 no.2
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• pp.80-84
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• 2016

Background: Video-assisted thoracoscopic surgery (VATS) pulmonary wedge resection has emerged as the standard treatment for primary spontaneous pneumothorax. Recently, single-port VATS has been introduced and is now widely performed. This study aimed to evaluate the outcomes of the Tower crane technique as novel technique using a 15-mm trocar and anchoring suture in primary spontaneous pneumothorax. Methods: Patients who underwent single-port VATS wedge resection in Chungnam National University Hospital from April 2012 to March 2014 were enrolled. The medical records of the enrolled patients were reviewed retrospectively. Results: A total of 1,251 patients were diagnosed with pneumothorax during this period, 270 of whom underwent VATS wedge resection. Fifty-two of those operations were single-port VATS wedge resections for primary spontaneous pneumothorax performed by a single surgeon. The median age of the patients was $19.3{\pm}11.5$ years old, and 43 of the patients were male. The median duration of chest tube drainage following the operation was $2.3{\pm}1.3days$, and mean post-operative hospital stay was $3.2{\pm}1.3days$. Prolonged air leakage for more than three days following the operation was observed in one patient. The mean duration of follow-up was $18.7{\pm}6.1months$, with a recurrence rate of 3.8%. Conclusion: The tower crane technique with a 15-mm trocar may be a promising treatment modality for patients presenting with primary spontaneous pneumothorax.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6615-6619
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• 2015

Background: The expression of HER-2 in prostate cancer has been linked to disease progression. We analysed the presence of HER-2 expression in primary tumors in men undergoing radical prostatectomy, its association with clinical and pathological findings, and its expression in secondary circulating prostate cells (CPCs) during follow up, as well as links with biochemical failure and the effects of androgen blockade. Materials and Methods: Consecutive men undergoing radical prostatectomy for histologically confirmed prostate cancer were analyzed. HER-2 expression in the primary tumor was assessed using the HercepTest(R), CPCs were identified from blood samples using standard immunocytochemistry with anti-PSA and positive samples with the HercepTest(R) to determine HER-2 expression. The influence of HER-2 expression on the frequency of biochemical failure and effects of androgen blockade was determined. Results: 144 men with a mean age of $64.8{\pm}10.3$ years participated, with a median follow up of 8.2 years. HER-2 was expressed in 20.8% of primary tumors; it was associated with vascular infiltration and older age, but not with other clinical pathological findings. Some 40.3% of men had secondary CPCs detected, of which 38% expressed HER-2. Men CPC (+) had a higher frequency of biochemical failure, but there was no difference in HER-2 expression of CPCs with the frequency of biochemical failure. After androgen blockade, men with HER-2 (+) positive secondary CPCs had a higher frequency of disease progression to castrate resistant disease. Conclusions: HER-2 plays a dual role in the progression of prostate cancer; firstly it may increase the potential of tumor cells to disseminate from the primary tumor via the blood by increasing vascular infiltration. In the presence of androgens, there is no survival advantage of expressing HER-2, but once biochemical failure has occurred and androgen blockade started, HER-2 positive cells are resistant to treatment, survive and grow leading to castration resistant disease.

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.2
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• pp.9-16
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• 2017

The study analyzed the heat losses and the building energy efficiency grade by the energy simulation using the ENERGY# and ECO2 programs for the three types of Standard design of rural houses. It was calculated the energy efficiency rating by the ECO2 program for the rural housing standard design, and the energy demand and the energy consumption by each factor were compared and analyzed. And it analyzed energy consumption by element of each house by ENERGY # program. As a result, first in the evaluation of the energy efficiency grade of buildings by the ECO2 program, the rating for primary energy requirement for the housing newly built by the standard design of rural house is expected to range from 2 to 4 with 189.3 to $238.7kWh/m^2.a$. Second, the energy loss of each part of standard design of rural housing occurs in the order of ventilation 39%, window 33%, outer wall 14%, roof 9%, bottom 5%, and energy loss through ventilation and window occurs more than 70%. Third, the most beneficial effects on the energy efficiency grade is obtained the lowest grade of all three types by 2 when the lowering of the window and door heat transmission rate and the lowering of the light density, and the heat exchange ventilation device is not installed. Fourth, in the standard design of rural housing, the energy demand is occupied by heating > hot water > lighting order, and the order of the weight is changed in order of heating > lighting > ventilation > hot water. Fifth, building energy efficiency assessment system needs to establish policy for fixing rural housing energy as a practical device to ensure energy performance and quality.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.6
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• pp.909-914
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• 2008

A coupling capacitor voltage transformer(CCVT) is used in an extra or ultra high voltage system to obtain the standard low voltage signal for protection. To avoid the phase angle error between the primary and secondary voltages, a tuning reactor is connected between a capacitor and a voltage transformer. The inductance of the reactor is designed based on the power system frequency. If a fault occurs on the power system, the secondary voltage of the CCVT contains some errors due to a dc offset component and harmonic components resulting from the fault. The errors become severe in the case of a close-in fault. This paper proposes an algorithm for compensating the secondary voltage of a CCVT in the time-domain. From the measured secondary voltage of the CCVT, the secondary and primary currents are obtained; then the voltage across the capacitor and the inductor is calculated and then added to the measured secondary voltage to obtain the correct primary voltage. Test results indicate that the proposed algorithm can compensate the distorted secondary voltage of the CCVT irrespective of the fault distance, the fault inception angle, and the burden of the CCVT.

• Journal of Environmental Health Sciences
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• v.7 no.1
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• pp.1-7
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• 1981

During 20 days from November 4 to 28, 1980, the quantities of grease and oil, BOD (biological oxygen demand), COD (chemical oxygen demand), SS (suspended solid) were measured at Grit Chamber, Primary Sedimentation Tank, Secondary Sedimentation Tank in Chung Gye Chun sewage treatment plant. The results were as follows. 1. The average of grease and oil quantities were 251mg/l at Grit Chamber, 185mg/l at Primary Sedimentation Tank, 47mg/l at Secondary Sedimentation Tank. 2. In the secondary treatment for the removal of grease and oil, the removed quantities of grease and oil were increased according to increasing the quantities of influent grease and oil. The regression equation were as follows G.O.removed=0.731 G.O. influent+3.235 (r=0.887) 3. The average of grease and oil removal rate was 76.4% and the standard deviation of grease and oil removal rate daily was 10.6%. 4. G.O. (grease and oil) and BOD, COD, SS showed significant correlationship at Grit Chamber, Primary Sedimentation Tank, Secondary Sedimentation Tank. (P<0.05). 5. In the secondary treatment, effluent grease & oil and other parameters were analyzed by means of Stepwise multiple regression. Multple regression equation for estimates of effluent grease and oil were as follows. $GO_E=-9.1637+2.0380 SS_E+0.068 SS_I$ (r=0.778) 6. The correlative parameters for the effluent grease and oil seem to be the influent SS and the effluent SS. 7. It was estimated that the removal of grease and oil would be improved by means of improvement of suspended solids removal efficiency but it is necessary to inquire further into the study.