• Archives of Pharmacal Research
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• 제25권6호
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• pp.770-780
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• 2002

The airway surface liquid (ASL), often referred to as mucus, is a thin layer of fluid covering the luminal surface of the airway. The major function of mucus is to protect the lung through mucociliary clearance against foreign particles and chemicals entering the lung. The mucus is comprised of water, ions, and various kinds of macromolecules some of which possess the protective functions such as anti-microbial, anti-protease, and anti-oxidant activity. Mucus glycoproteins or mucins are mainly responsible for the viscoelastic property of mucus, which is crucial for the effective mucociliary clearance. There are at least eight mucin genes identified in the human airways, which will potentially generate various kinds of mucin molecules. At present, neither the exact structures of mucin proteins nor their regulation are understood although it seems likely that different types of mucins are involved in different functions and might also be associated with certain airway diseases. The fact that mucins are tightly associated with various macromolecules present in ASL seems to suggest that the defensive role of ASL is determined not only by these individual components but rather by a combination of these components. Collectively, mucins in ASL may be compared to aircraft carriers carrying various types of weapons in defense of airborne enemies.

• Tribology and Lubricants
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• 제31권5호
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• pp.205-212
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• 2015

In this research, effects of profile changes of stem section of the plunger on the lubrication characteristics of a fuel injection pump (FIP) were evaluated by hydrodynamic lubrication analysis. The clearance between plunger and barrel was divided into two regions, head and stem. The head was not involved in preventing a decrease of fuel oil pressure. So, research efforts were focused on both edges of the plunger’s stem. The two -dimensional Reynolds equation was used to evaluate lubrication characteristics with variations in viscosity, clearance and profile for a laminar, incompressible, unsteady-state flow. Moreover, the equilibrium equation of moment and forces in the vertical and horizontal directions were used to determine the motion of the plunger. The equations were discretized using the finite difference method. Lubrication characteristics of the FIP were investigated by comparing the dimensionless minimum film thickness, or film parameter, which is the ratio of minimum film thickness to surface roughness. Through numerical analyses, we showed that the profile of the lower edge of the stem had no effect on lubrication characteristics, but the profile of the upper edge had a significant influence on lubrication characteristics. In addition, changes in the profile were more effective in improving lubrication characteristics under low viscosity conditions.

• 통상정보연구
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• 제9권2호
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• pp.327-350
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• 2007

A single window platform must be successfully established by implementing CDM/UCR in WCO and UNeDocs in UN/CEFACT, which is part of the framework of standards for secure and facilitate global trade. Core success factors in single window platform for international trade depend on political innovative capacity, advanced leadership of high ranking officials and departments in charge, effective collaborations between the ministries and offices concerned which are supported by supreme executives, self-controlled coordinations between users, convenience and access availability to users, promotion and marketing, identification on predictive impediments, financial raising and revenue model payable, communication's strategy, valid legal basis etc. To settle a stable ubiquitous e-trade platform, firstly, procedures and practices of customs clearance which different from one another mutually must be standardized globally. Secondly, the international standard electronic data exchanges must be introduced to facilitate and simplify customs clearing procedures by holding administrative informations in common between public institutions. thirdly, cooperative work model must be accepted with enhancing outsourcing business between reference groups (export-import firms and IT service providers).

• 한국정밀공학회지
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• 제19권1호
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• pp.65-70
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• 2002

An analysis method for calculating motion accuarcy of double sides hydrostatic table is proposed in this paper. In this method, profiles of each rails are assumed as periodic function, therefore it is represented as the sum of spacial frequencies. Bearing clearance at any position rail is depended on the variation of linear, angular motion error of table and the form errors of both sides of a rail. Finite element method is applied to calculate pressure distributions in bearing clearance. In order to simplify the analyzing process, double sides table model is converted into equivalent single side table model. Results calculated by the proposed modeling method agree well with the results directly caculated by double sides modeling method, and also agree well with experimental results. From the theoretical and experimental analysis, it is verified that the proposed analysis method is very effective to analyze the motion accuracy of double sides hydrostatic table.

• Tribology and Lubricants
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• 제31권5호
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• pp.213-220
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• 2015

This study evaluates the effect of grooves on the stem part of a plunger on the lubrication characteristics of a fuel injection pump (FIP) by using hydrodynamic lubrication analysis. The current study uses the two-dimensional Reynolds equation to evaluate the changes in lubrication characteristics with variations in clearance, viscosity, and grooves for a laminar, incompressible, and unsteady state flow. This study investigates the lubrication characteristics by comparing the dimensionless minimum film thickness or the film parameter, which is the ratio of the minimum film thickness to surface roughness. The analysis method for the groove section differs depending on the depth of the groove. For instance, in the case of a shallow groove, the film thickness equation considers the depth of the groove, while in the case of a deep grove, it considers the flow continuity. The lubrication characteristics of the FIP are more sensitive to changes in the groove width than to changes in other design variables. Moreover, the application of a groove is more effective under low viscosity conditions. The smaller the distance from the edge of the stem part to the first groove in the case of shallow grooves, the better are the lubrication characteristics of the FIP. In contrast, in the case of deep grooves, the lubrication characteristics of the FIP improve as the distance increases. The application of shallow grooves is more effective for improving the lubrication characteristics than the application of deep grooves.

• 한국전문물리치료학회지
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• 제16권3호
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• pp.1-8
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• 2009

It is important to find the effective position for cough and sputum clearance in respiratory physical therapy. The purpose of this study was to compare the changes in peak expiratory flow (PEF), forced expiratory volume in 1 second ($FEV_1$), and peak cough flow (PCF) related to functional level and measurement position in patients with Duchenne muscular dystrophy. Twenty one subjects were classified into three functional levels, and measurements was undertaken in three different measurement positions (upright sitting, $45^{\circ}$ reclining and supine). Vitalograph PEF/FEV DIARY was used to measure PEF and $FEV_1$, and Ferraris Pocket Peak was used to measure PCF. Mixed two-way analysis of variance and Bonferroni post-hoc test were used for statistical analysis. The results of the study were as follows: 1) Significant main effects for measurement position were found. 2) PEF was the highest in upright sitting, followed by $45^{\circ}$ reclining, and supine in order. 3) $FEV_1$ in upright sitting and $45^{\circ}$ reclining were significantly greater compared with that in supine. 4) PCF in upright sitting and $45^{\circ}$ reclining were significantly greater compared with that in supine. 5) No significant main effects for functional level were found in PEF, $FEV_1$, and PCF. 6) No significant functional level by measurement position interactions were found in PEF, $FEV_1$, and PCF. Therefore, it is concluded that upright sitting and $45^{\circ}$ degree reclining positions are recommended for effective cough and sputum clearance.

• 동의생리병리학회지
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• 제33권5호
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• pp.295-301
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• 2019

The purpose of this study is to assess potential effects of the effects of Korean Medicine treatments on condyloma. Retrospective study of 194 patients with diagnosed condyloma in Saengki Korean Medicine Clinic from October 2013 to September 2018 was done. Patients were treated with Korean Medicine treatments such as herbal treatment, pharmacopuncture and moxibustion. The data has been analyzed by chi-squared distribution and t-test. A total of 194 patients were 148 males and 46 females. In the aspect of diagnosis, newly diagnosed patients were 96 and recurrent patients were 98. After the treatment, in the light of size complete clearances were 110 patients, partial clearances were 63 and non responses were 21. And in the light of number complete clearances were 110 patients, partial clearances were 68 and non responses were 16. In complete clearance group, the relation among the treatment period, sex, age, and the site of wart showed statistically significant. There were 3 recurrences of warts in the 6 months of follow-up observation for 110 of clearance group. No major side effects related to the treatment were found. As the result of t-test shows, the Korean Medicine treatment we had applied revealed as statistically effective on both number(t=11.471, p<.001) and size(t=11.951, p<.001) of the wart. The result of this study suggests that additional treatment of Korean medicine such as acupuncture and moxibustion treatment could be effective on condyloma patients.

• 한국콘텐츠학회논문지
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• 제14권6호
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• pp.255-261
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• 2014

의료현장에서의 방사성폐기물은 방사성동위원소의 사용량의 증가와 더불어 급격히 늘어나고 있다. 특히, 갑상선 질병의 진단 및 치료용으로 사용량이 증가하고 있는 I-131 핵종의 경우 8.02 일의 짧은 반감기를 가지고 있으며, 관련 폐기물은 모두 자체처분 방법으로 처분하고 있다. 이와 관련하여 국제원자력기구(IAEA)는 개인선량(10 ${\mu}Sv/y$) 및 집단선량(1 man-Sv/y)과 핵종별 농도에 근거하여 각각 폐기물의 규제해제기준을 제시(IAEA Safety Series No 111-P-1.1, 1992 및 IAEA RS-G-1.7, 2004)하였다. 이 연구에서는 의료현장에서 발생하는 I-131 핵종 관련 폐기물을 사용상 종류별로 수집 및 측정하여 방사능농도의 측정 방법 및 절차를 수립한다. 또한, 측정 결과를 바탕으로 핵종의 감쇠 유도식을 산출하고, 이것을 바탕으로 자체처분 가능일자를 산출하여 이론식의 경우와 대비하여 고찰하였다. 측정 결과를 바탕으로 유도 감쇠식을 신정하여 이론적 반감기와 유효 반감기를 비교해 본 결과, I-131 핵종의 이론적 반감기가 유효반감기(7.72일)에 비해 긴 반감기를 가지고 있음을 확인하였다. 측정결과를 바탕으로 한 유효 반감기를 적용한다면, 현재보다 더 짧은 기간 동안 I-131 핵종 폐기물을 보관하였다가 자체처분을 할 수 있다. 이 연구 결과는 ISO 표준으로 추진할 예정이다.

• Tribology and Lubricants
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• 제19권6호
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• pp.357-364
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• 2003

The sub­surface stress field beneath the gear's contact surface caused by the contact pressure in lubricated condition has been calculated. To evaluate the influence of the clearance shape on the stress field, two kinds of tooth profile models were chosen. One is the conventional cylinder contact model and the other is the new numerical model. Love's rectangular patch solution was used to obtain the sub­surface stress field. The analysis results show that the sub­surface stress is quite dependent on both the contact pressure and the profile model. The maximum effective stress of the new model is lower than that of the old model. The depth where the maximum effective stress occurs in the new model is not proportional to the intensity of the external load.

• 해양환경안전학회지
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• 제3권2호
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• pp.77-84
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• 1997

For the effective treatment of shipboard sewage continuously, a non-diaphragm electrolytic treatment device using DSA type insoluble electrode, Ti/IrO2, anode and H-C metal cathode, was studied. The most effective electrolytic conditions were obtained when cell clearance, 6mm, pH 5-6 and the concentration of seawater, more than 20% as batch test results. The COD removal rate was varied in logarithmic function, showed as C=Coe-KE and the required current was E = A/QCo [A.min/mgCOD]. When the COD removal effeciency was more than 90%, the electrolytic reaction constant was 0.02.