• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.321-326
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• 2000

This study was performed to analyze the variation of inside temperature of greenhouse according to shading methods. We used two shading method of external and internal method. The shading effect of external screen was superior to internal screen. Soil temperature of greenhouse without screen was higher than outside soil temperature, but the value of greenhouse with internal and external screen was lower than outside.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.169-172
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• 2006

Wall construction apartment built before 1988 years need internal examination reinforcement according to existing laws ans regulations at remodeling because do not earthquake resistant design. Established newly wall to interest paid back at the same time a the principal direction for wall construction apartment internal examination reinforcement, and satisfied internal examination standard because uses width displacement between floor. This study analyzes displacement value such as latitude and presented position of efficient reinforcement wall and wall quantity at earthquake resistant design of wall construction apartment.

• 소음진동
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• 제11권2호
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• pp.257-264
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• 2001

In this research, piezoelectric smart structures are applied for SEA(Statistical Energy Analysis), which is well known approach for high frequency analysis. A new input power measurement based on piezoelectric electrical power measurement is proposed and compared with the conventional method in SEA. As an example, a simple aluminum beam on which piezoelectric actuator is attached is considered. By measuring the electrical impedance and electrical current of the piezoelectric actuator, the electrical power given on the actuator is found and this is In turn converted into the mechanical energy. From the measured value of the stored energy of the beam, the Internal loss factor is calculated and this value shows a good agreement with that given by the conventional method as well as the theoretical value. To compare the coupling loss factor, L-shape beam system which consists of a aluminum beam subsystem and a steel beam subsystem coupled by three pin is taken as second example. The input power and stored energy of each subsystem are found by the proposed approach. The coupling loss factor found by the electrical input power obtained from the piezoelectric actuator exhibits similar trend to the value found by the conventional method as well as the theoretical value. In conclusion, the use of SEA for high frequency application of piezoelectric smart structures is Possible. Especially, the input power that is essential for SEA can be found accurately by measuring the electrical input power of the piezoelectric actuator.

• 대한한방내과학회지
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• 제25권4호
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• pp.147-157
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• 2004

Objectives : This experiment was done to evaluate the effects of Hyuntogobon-hwan(HTG) on antioxidant capability and lipidic concentration in blood, both of which are presumed to be related to aging. Methods : 12 week-old SD rats were divided into controlled group, uncontrolled group and HTG group. As controlled and HTG groups were given subcutaneous injection of D-galactose(50mg/kg/rat), at the same time HTG group was administered extract of Hyuntogobon-hwan(270mg/200g). HTG injections continued for 6 weeks. After initial injections, blood was drawn from each group and the following were measured: the activity of SOD, GSH-px, catalase in erythrocytes, TSARS value, concentration of total lipid, tryglyceride in blood plasma. Results : The activities of SOD and GSH-px in erythrocytes increased significantly in HTG group compared with controlled group. The activity of catalase seemed to increase slightly, but it was barely noticeable. The concentration of total lipid in plasma decreased significantly in HTG group compared with controlled group. The value of TBARS in plasma seemed to decrease slightly, but it was barely noticeable. Conclusions : According to the above results, Hyuntogobon-hwan has an influence on aging by virtue of activation of antioxidative enzyme systems in erythrocytes and concentrations of lipid in blood plasma.

• 전기학회논문지
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• 제61권12호
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• pp.1801-1806
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• 2012

This paper presents a simple and practical method which enables to prevent malfunction of protection relay due to differential current caused by one end CT saturation in case of external fault. This method uses difference of magnitude(instantaneous value) between the both end current just before the occurrence of differential current without a separate method to CT staturation detection. One end CT saturation is simulated by current transformer model using type-96 component and the presented method is verified by using EMTP MODELS with respect to internal and external fault with one end CT staturation. The presented method distinguished rightly bewteen external and internal fault with one end CT saturation. This information can be used to prevent malfunction of current differential protection relay in case of external fault. And this method is not affected by sampling rate and has no calculation burden, so it will be applicable to differential current protection relay with ease.

• 대한기계학회논문집A
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• 제21권12호
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• pp.1973-1983
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• 1997

Higher order isoparametric elements are usually used in the finite element analysis because they can represent easily the geometric shape of a complex structure ad can improve the solution quality. When these elements are used, the position of internal nodes affects greatly on the solution accuracy. Decreasing of the accuracy related to the position of internal nodes is due to non-conformal mapping often results in an unstable Jacobian value. This paper, in order to remove this difficulty, suggests a modified shape function which can establish conformal mapping between two coordinate systems. Numerical experiments with the proposed shape function show that a stable solution can be obtained without respect to the position of internal nodes, and offer convenience that one can take arbitrarily the position of internal nodes considering only the geometric shape of element boundaries.

• 대한치과보철학회지
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• 제46권3호
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• pp.246-254
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• 2008

STATEMENT OF PROBLEM: The cast abutment has advantages of overcoming angulation problem and esthetic problem. However, when a gold-machined UCLA abutment undergoes casting, the abutment surfaces in contact with the implant may change. PURPOSE: The purpose of this study was to compare the detorque values of prefabricated machined abutments with gold-premachined cast-on UCLA abutments before and after casting in two types of internal implant-abutment connection systems: (1) internal hexagonal joint, (2) internal octagonal joint. Furthermore, the detorque values of two implant-abutment connection systems were compared. MATERIALS AND METHODS: Twenty internal hexagonal implants with an 11-degree taper and twenty internal octagonal implants with an 8-degree taper were acquired. Ten prefabricated titanium abutments and ten gold-premachined UCLA abutments were used for each systems. Each abutment was torqued to 30 N㎝ according to the manufacturer's instructions and detorque value was recorded. The detorque values were measured once more, after casting with gold alloy for UCLA abutment, and preparation for titanium abutments. Group means were calculated and compared using independent t-test and paired t-test (${\alpha}$=0.05). RESULTS: The results were as follows: 1. The detorque values between titanium abutments and UCLA-type abutments showed significant differences in internal octagonal implants (P<0.05), not in internal hexagonal implants (P>0.05). 2. In comparison of internal hexagonal and octagonal implants, the detorque values of titanium abutments had significant differences between two connection systems on the initial analysis (P<0.05), not on the second analysis (P>0.05) and the detorque values of UCLA-type abutments were not significantly different between two connection systems (P>0.05). 3. The detorque values of titanium abutments and UCLA-type abutments decreased significantly on the second analysis than the initial analysis in internal hexagonal implants (P<0.05), not in internal octagonal implants (P>0.05). CONCLUSION: Casting procedures of UCLA-type abutments had no significant effect on screw loosening in internal implant-abutment connection systems, and UCLA-type abutments showed higher detorque values than titanium abutments in internal octagonal implants.

• 대한치과보철학회지
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• 제41권4호
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• pp.393-404
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• 2003

Statement of problem. Higher incidence of prosthetic complications such as screw loosening, screw fracture has been reported for posterior single tooth implant. So, there is ongoing research regarding stability of implant-abutment interface. One of those research is increasing the implant diameter and prosthetic table width to improve joint stability. In another part of this research, internal conical type implant-abutment interface was developed and reported joint strength is higher than traditional external hex interface. Purpose. The purpose of this study is to compare stress distribution in single molar implant between external hex butt joint implant and internal conical joint implant when increasing the implant diameter and prosthetic table width : 4mm diameter, 5mm diameter, 5mm diameter/6mm prosthetic table width. Material and method. Non-linear finite element models were created and the 3-dimensional finite element analysis was performed to see the distribution of stress when 300N static loading was applied to model at $0^{\circ},\;15^{\circ},\;30^{\circ}$ off-axis angle. Results. The following results were obtained : 1. Internal conical joint showed lower tensile stress value than that of external hex butt joint. 2. When off-axis loading was applied, internal conical joint showed more effective stress distribution than external hex butt joint. 3. External hex butt joint showed lower tensile stress value when the implant diameter was increased. 4. Internal conical joint showed lower tensile stress value than external hex butt joint when the implant diameter was increased. 5. Both of these joint mechanism showed lower tensile stress value when the prosthetic table width was increased. Conclusion. Internal conical joint showed more effective stress distribution than external hex joint. Increasing implant diameter showed more effective stress distribution than increasing prosthetic table width.

• 대한한방내과학회지
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• 제31권3호
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• pp.467-476
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• 2010

Object : The purpose of this study was to investigate the correlation of atherosclerosis risk factors and pulse wave velocity (PWV) of carotid-femoral artery with Sasang constitution. This study also aimed to investigate the relationship between PWV and risk factors of atherosclerosis, including serum cholesterol and homosisteine, hs-CRP. Methods : We enrolled 160 patients without experience strokes who visited our hospital for a medical examination from January 1, 2008 to April 30, 2010 except patients whose body constitutions were undetermined according to QSCCII. We investigated the correlation between serum cholesterol values, blood pressure, body mass index(BMI), homosistein, hs-CRP and PWV. Pearson's correlation and partial correlation analysis were applied to examine the relationship between PWV and risk factors of atherosclerosis. Result : Among the 160 subjects, 54 were Taeumin, 54 were Soyangin, and 52 were Soeumin. The prevalences of high BMI (P-value <0.01), high hs-CRP(P-value <0.05), and high PWV(P-value <0.05) of Taeumin were higher than those of the other constitutions. PWV of carotid-femoral artery was significantly different among the three constitutional groups(Taeumin: $8.12{\pm}1.64m/sec$, Soyangin: $7.48{\pm}1.16m/sec$, Soeumin: $7.49{\pm}1.12m/sec$)(P-value <0.05). This research has show a statistical significance between the average amount of carotid-femoral artery PWV that is higher in Taeumin. Age factor of Taeumin was the effective determinant of the increase of mean PWV of carotid-femoral arteries. Conclusions : There were significant differences in the prevalence of atherosclerosis according to Sasang constitution. This study showed that atherosclerosis was more prevalent in Taeumin. Therefore, according to our results, risk of atherosclerosis was higher in Taeumin than among other constitutions.

• 한국콘텐츠학회논문지
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• 제18권1호
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• pp.132-142
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• 2018

본 연구는 기업 외부와 내부 환경요소들이 외부주체와의 협력 추진에 미치는 영향을 기업의 해외직접투자로서의 해외생산법인의 유무에 따른 차이와 함께 규명하고자 한다. 본 연구는 지금까지 협력(제휴)과 관련하여 그 결정요인에 대한 연구는 다양하게 분석이 이루어 졌으나, 해외직접투자의 유무에 따라 외부와 내부환경요소로 나뉘어 복합적 분석을 한 연구는 거의 찾아보기 어렵기 때문에 이를 규명하고자 하였다. 분석 결과로는 해외직접투자를 한 기업은 내부요인 중 설비투자의 효율, 가격경쟁력, 3년간 투자실적이 각각 유효한 제휴의 동기로 나타났고, 해외직접투자를 하지 않은 기업은 외부요인인 비용구조의 불확실성, 내부요인인 가격경쟁력, 투자실적이 유효한 결과로 나타났다. 결국, 본 연구에서는 해외직접투자를 한 기업과 해외직접투자를 하지 않는 기업은 모두 내부역량인 가격경쟁력과 3년간의 투자실적이 중요한 협력의 동기가 된다는 것과, 해외투자를 한 기업과 해외투자를 하지 않는 기업의 차이는 해외직접투자를 한 기업은 내부요인에서 설비투자의 효율이, 해외직접투자를 하지 않는 기업은 외부요인 중 비용구조의 불확실성이 각각 주요한 환경요인이 된다는 것을 규명하였다. 종합하여 보면, 본 연구의 시사점은 기업의 내부역량은 협력의 중요한 동기가 된다는 동시에 내부역량 강화는 또한 기업이 다른 기업과의 협력의 기회를 넓혀준다는 것이다.