• Wind and Structures
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• 제16권1호
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• pp.93-115
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• 2013

This paper describes a study of the influence of a dynamically flexible building structure on pressures inside and net pressures on the roof of low-rise buildings with a dominant opening. It is shown that dynamic interaction between the flexible roof and the internal pressure results in a coupled system that is similar to a two-degree-of-freedom mechanical system consisting of two mass-spring-damper systems with excitation forces acting on both the masses. Two resonant modes are present, the natural frequencies of which can readily be obtained from the model. As observed with quasi-static building flexibility, the effect of increased dynamic flexibility is to reduce the first natural frequency as well as the corresponding peak value of the admittance, the latter being the result of increased damping effects. Consequently, it is found that the internal and net roof pressure fluctuations (RMS coefficients) are also reduced with dynamic flexibility. This model has been validated from experiments conducted using a cylindrical model with a leeward end flexible diaphragm, whereby good match between predicted and measured natural frequencies, and trends in peak admittances and RMS responses with flexibility, were obtained. Furthermore, since significant differences exist between internal and net roof pressure responses obtained from the dynamic flexibility model and those obtained from the quasi-static flexibility model, it is concluded that the quasi-static flexibility assumption may not be applicable to dynamically flexible buildings. Additionally, since sensitivity analyses reveal that the responses are sensitive to both the opening loss coefficient and the roof damping ratio, careful estimates should therefore be made to these parameters first, if predictions from such models are to have significance to real buildings.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2533-2540
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• 2013

Background: Although screening is necessary where gastric cancer is particularly common in Asia, the performance outcomes of mass screening programs have remained unclear. This study was conducted to evaluate cost-effectiveness outcomes of the national cancer screening program (NCSP) for gastric cancer in South Korea. Materials and Methods: People aged 40 years or over during 2002-2003 (baseline) were the target population. Screening recipients and patients diagnosed with gastric cancers were identified using the NCSP and Korea Central Cancer Registry databases. Clinical outcomes were measured in terms of mortality and life-years saved (LYS) of gastric cancer patients during 7 years based on merged data from the Korean National Health Insurance Corporation and National Statistical Office. We considered direct, indirect, and productivity-loss costs associated with screening attendance. Incremental cost-effectiveness ratio (ICER) estimates were produced according to screening method, sex, and age group compared to non-screening. Results: The age-adjusted ICER for survival was 260,201,000-371,011,000 Korean Won (KW; 1USD=1,088 KW) for the upper-gastrointestinal (UGI) tract over non-screening. Endoscopy ICERs were lower (119,099,000-178,700,000 KW/survival) than UGI. To increase 1 life-year, additional costs of approximately 14,466,000-15,014,000 KW and 8,817,000-9,755,000 KW were required for UGI and endoscopy, respectively. Endoscopy was the most cost-effective strategy for males and females. With regard to sensitivity analyses varying based on the upper age limit, endoscopy NCSP was dominant for both males and females. For males, an upper limit of age 75 or 80 years could be considered. ICER estimates for LYS indicate that the gastric cancer screening program in Korea is cost-effective. Conclusion: Endoscopy should be recommended as a first-line method in Korea because it is beneficial among the Korean population.

• 대한화학회지
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• 제59권3호
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• pp.215-224
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• 2015

Unsymmetrical tetradentate Schiff base N-(2-hydroxy-5-methylacetophenone)-N'-(2-hydroxy acetophenone) ethylene diamine (H₂L) and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, IR, electronic spectra and thermogravimetric analyses. ¹H, ¹³C-NMR and FAB Mass spectra of ligand clearly indicate the presence of OH and azomethine groups. Elemental analyses of the complexes indicate that the metal to ligand ratio is 1:1 in all complexes. Infrared spectra of complexes indicate a dibasic quadridentate nature of the ligand and its coordination to metal ions through phenolic oxygen and azomethine nitrogen atoms. The thermal behavior of these complexes showed the loss of lattice water in the first step followed by decomposition of the ligand in subsequent steps. The thermal data have also been analyzed for the kinetic parameters by using Horowitz-Metzger method. The dependence of the electrical conductivity on the temperature has been studied over the temperature range 313-403 K and the complexes are found to show semiconducting behavior. XRD and SEM images of some representative complexes have been recorded. The antimicrobial activity of the ligand and its complexes has been screened against various microorganisms and all of them were found to be active against the test organisms. The Fe(III) and Ni(II) complex have been tested for the catalytic oxidation of styrene.

• 한국지반환경공학회 논문집
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• 제15권12호
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• pp.5-13
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• 2014

본 연구에서는 발포질석을 글리세롤로 코팅하여 인에 대한 흡착력을 높인 발포질석 흡착제 제조 및 인 제거능력을 평가하였다. 발포질석과 4 mol%의 황산을 포함한 글리세롤을 1:4 비율로 혼합 후 380, 580, $780^{\circ}C$로 가열하여 다공성 탄소층을 발포질석 표면에 부착하였다. $380^{\circ}C$로 가열한 질석의 경우 비표면적인 $53.1m^2/g$을 나타내었으며, TGA 분석을 통해 탄소성분의 산화로 인한 질량손실이 가장 큰 것으로 분석되었다. $380^{\circ}C$로 제조된 코팅 발포질석을 이용한 수용액 속의 인 제거를 흡착모델에 적용해보니 Langmuir 모델에 더 적합하며 여기로부터 구한 최대제거량은 714.3 mg/kg으로 기존 점토광물을 이용한 인 흡착연구결과보다 더 흡착용량이 뛰어난 것을 알 수 있었다.

• 콘크리트학회논문집
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• 제24권1호
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• pp.53-60
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• 2012

이 연구의 목적은 자연모래를 사용한 콘크리트(NSC)와 부순모래를 사용한 콘크리트(CSC)의 고온 하에서의 물리, 역학적인 특성을 조사하는 것이다. 시험체를 $23^{\circ}C$에서 $800^{\circ}C$ 범위에 노출시켜 육안검사와 중량손실을 측정하였으며, 압축강도 시험과 할렬 인장강도 시험을 수행하였다. 그 결과 중량손실률은 노출 온도가 증가할수록 감소하였으며, NSC와 CSC의 감소율은 비슷하였다. 압축강도, 할렬 인장강도와 탄성계수 또한 노출온도가 증가할수록 감소하였다. NSC의 잔존 압축강도는 $200^{\circ}C$와 $400^{\circ}C$에서 CSC보다 급격히 감소했으며, NSC의 잔존 할렬 인장강도 또한 $200^{\circ}C$에서 CSC 보다 급격하게 감소했다. 하지만 CSC와 NSC 공히 $800^{\circ}C$에 노출되었을 때는 비슷한 잔존강도를 나타내었다.

• Journal of Nutrition and Health
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• 제34권7호
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• pp.786-796
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• 2001

To assess calcium and sodium and urinary excretion of preschool children in Busan and to evaluate the relationship of intakes of food and nutrient with urinary calcium excretion, calcium and sodium food frequencies of 25 common foods affecting intakes of calcium and sodium per week, nutrient intake by 24hr recall and 24hr urinary calcium and sodium excretion were measured with 97 preschool children. The mean calcium intake was 436.11mg and below RDA. The mean sodium intake was 1890.11mg. The mean urinary calcium and sodium excretion were 42.88mg and 735.25mg respectivery. The mean urinary calcium/creatinine ratio was 0.20. The urinary calcium excretion showed positive significant correlations with weight, intake frequency of pizza consumed per week and urinary sodium excretion (p<0.05, p<0.05, p<0.001). The urinary calcium excretion per milligram of creatinine showed positive significant correlations with intake frequencies of pizza and common squid consumed per week(p<0.01, p<0.05) and negative correlation with intake frequencies of pizza and common squid consumed per week(p<0.01, p<0.05) and negative correlation with age(p<0.05). No significant relations were found between urinary calcium and intakes of calcium, protein and phosphorus. Urinary sodium was found to be the most important determinant of urinary calcium excretion. Intake frequency of pizza consumed per week was found to be the most important determinant of urinary calcium excretion per milligram of creatinine. Based on the results, urinary calcium excretion was related to intake frequency of pizza consumed per week and urinary sodium excretion. Low calcium intake and increase of calcium loss in the urine potentiated by sodium intake during growth may reduce peak bone mass. So nutritional education is needed in order to increase calcium intake and decrease sodium intake, especially from food like pizza.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권5호
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• pp.519-526
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• 2000

Osteoporosis has recently been recognized as a major health problem in the elderly population. The disorder is manifested as a loss of bone mass accompanied by structural alteration of bone and increased incidence of fracture. Mandible also may be affected. So, I evaluated panoramic views of 66 postmenopausal women for finding the possibility of useful diagnostic mandibular parmeters of osteoporosis. To know the correlationship between skeleton and mandible, the average of the bone mineral density of lumbar from 2nd to 4th by the dual energy X-ray absorptiometry(DEXA, LUNAR DPZ. USA), and age and mandibular parameters, that is, the number of residual teeth, alveolar ridge resorption ratio, panoramic mandibular index (PMI), mandibular cortical width (MCW), angular cortical thickness (ACT), ramus cortical thickness (RCT), morphology of mandibular inferior cortical (MIC) were compared. And I divided the all tested women to the osteoporotic group and non-osteoporotic group by the use of T-score -2.0, which was derived from skeletal bone mineral density (BMD). To find the correlationship of the each group with mandibular parameters, t-test and discriminant analysis were done. The results of the t-test were that all parameters were highly related with 2 groups (p<0.05). Especially ACT, MIC, age have had even higher correlationship than others (p<0.001). The results of the discriminant analysis by the use of these ACT, MIC and age were that the discriminant function was Z = -2.973+(-1.447)$\times$(ACT)+1.131$\times$(MIC score)+(0.052)$\times$(age), the cutting score was 0.257 and the classification accuracy was 84.8%. Therefore I suggest that the consideration of the angular cortical thickness (ACT), the age of patient and the morphology of mandibular inferior cortical(MIC) may help find the osteoporosis.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8235-8238
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• 2016

Background: Lung cancer is one of the most common types of cancer causing high morbidity and mortality worldwide. An increasing incidence of lung cancer has been observed in India. Objectives:To evaluate the clinicpathological profile and haematological abnormalities associated with lung cancer in Bangalore, India. Materials and Methods: This prospective study was carried out over a period of 2 years. A total of 96 newly diagnosed and histopathologically confirmed cases of lung cancer were included in the study. Results: Our lung cancer cases had a male to female ratio of 3:1. Distribution of age varied from 40 to 90 years, with a major contribution in the age group between 61 and 80 years (55.2%). Smoking was the commonest risk factor found in 69.7% of patients. The most frequent symptom was cough (86.4%) followed by loss of weight and appetite (65.6%) and dyspnea (64.5%). The most common radiological presentation was a mass lesion (55%). The most common histopathological type was squamous cell carcinoma (47.9%), followed by adenocarcinoma (28.1%) and small cell carcinoma (12.5%). Distant metastasis at presentation was seen in 53.1% patients. Among the haematological abnormalities, anaemia was seen in 61.4% of patients, leucocytosis in 36.4%, thrombocytosis in 14.5% and eosinophilia in 19.7% of patients. Haematological abnormalities were more commonly seen in non small cell lung cancer. Conclusions: Squamous cell carcinoma was found to be the most common histopathological type and smoking still remains the major risk factor for lung cancer. Haematological abnormalities are frequently observed in lung cancer patients, anaemia being the commonest of all.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.551-555
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• 2010

Electrowetting is a versatile tool to handle tiny droplets and forms a backbone of digital microfluidics. Numerical analysis is necessary to fully understand the dynamics of electrowetting, especially in designing electrowetting-based devices, such as liquid lenses and reflective displays. We developed a numerical method to analyze the general contact-line problems, incorporating dynamic contact angle models. The method is based on the conservative level set method to capture the interface of two fluids without loss of mass. We applied the method to the analysis of spreading process of a sessile droplet for step input voltages and oscillation of the droplet for alternating input voltages in electrowetting. The result was compared with experimental data. It is shown that contact line friction significantly affects the contact line motion and the oscillation amplitude. The pinning process of contact line was well represented by including the hysteresis effect in the contact angle models. In level set method, in the mean time, material properties are made to change smoothly across an interface of two materials with different properties by introducing an interpolation or smoothing scheme. So far, the weighted arithmetic mean (WAM) method has been exclusively adopted in level set method, without complete assessment for its validity. We viscosity, thermal conductivity, electrical conductivity, and permittivity, can be an alternative. I.e., the WHM gives more accurate results than the WAM method in certain circumstances. The interpolation scheme should be selected considering various characteristics including type of property, ratio of property of two fluids, geometry of interface, and so on.

• 대한기계학회논문집B
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• 제36권9호
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• pp.937-944
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• 2012

선박의 주 추진용 디젤엔진에서 배출되는 배기가스의 폐열을 회수하는 발전시스템에 대하여, 작동유체로서 물이 적용된 3 변 사이클에 대한 열역학적 특성을 이론적으로 조사하였다. 그 결과로, 하나의 열원이 주어지면, 에너지 및 엑서지 효율은 터빈입구에서 작동유체에 대한 압력 및 온도의 특정한 조건에 의하여 최대화될 수 있었다. 그러한 조건에 대하여 응축온도의 증가에 따라, 터빈의 체적 팽창비를 적절하게 감소시킬 수 있었는데, 열원의 엑서지 손실률 및 응축기에서 엑서지 파괴율이 크게 증가되었다. 따라서, 상부 사이클에서 버려지는 엑서지를 회수하기 위하여, 저온 열원에 적합한 유기랭킨사이클을 하부 사이클로 적용하는 복합 사이클이 유용할 수 있다.