• 한국환경과학회지
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• 제19권8호
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• pp.971-981
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• 2010

The objectives of this study were to measure ambient total gaseous mercury (TGM) concentrations in Seoul, to analyze the characteristics of TGM concentration, and to identify of possible source areas for TGM using back-trajectory based hybrid receptor models like PSCF (Potential Source Contribution Function) and RTWC (Residence Time Weighted Concentration). Ambient TGM concentrations were measured at the roof of Graduate School of Public Health building in Seoul for a period of January to October 2004. Average TGM concentration was $3.43{\pm}1.17\;ng/m^3$. TGM had no notable pattern according to season and meteorological phenomena such as rainfall, Asian dust, relative humidity and so on. Hybrid receptor models incorporating backward trajectories including potential source contribution function (PSCF) and residence time weighted concentration (RTWC) were performed to identify source areas of TGM. Before hybrid receptor models were applied for TGM, we analysed sensitivities of starting height for HYSPLIT model and critical value for PSCF. According to result of sensitivity analysis, trajectories were calculated an arrival height of 1000 m was used at the receptor location and PSCF was applied using average concentration as criterion value for TGM. Using PSCF and RTWC, central and eastern Chinese industrial areas and the west coast of Korea were determined as important source areas. Statistical analysis between TGM and GEIA grided emission bolsters the evidence that these models could be effective tools to identify possible source area and source contribution.

• 보건의료산업학회지
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• 제9권2호
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• pp.89-102
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• 2015

Patients unable to speak are at higher risk for untreated pain. Use of valid behavioral and physiologic measures for pain is highly recommended for uncommunicative patients. This study was performed to compare the reliability and validity of NVPS-K and CPOT-K for pain assessment of nonverbal patients. This study was conducted from July to November 2011. A total of 29 nonverbal adult patients admitted to a university hospital intensive care unit participated in this study. Interrater reliability of the NVPS-K and CPOT-K had intermediate to high intraclass correlation coefficients (NVPS-K 0.680 ~ 0.921, CPOT-K 0.710 ~ 0.896). Discriminant validity was supported with higher instrument scores during turning and endotracheal suctioning than that of NIBP. For criterion validity, the NVPS-K scores were correlated to the self-reported pain of the patients but not the CPOT-K scores. The areas under the ROC curve for the NVPS-K and CPOT-K were 0.748 and 0.696 with cutoff points of 1 and 2, respectively. Thus, the NVPS-K and CPOT-K had a sensitivity and specificity of 94.7% and 45.0%, and 60.5% and 75.0%, respectively. The NVPS-K and CPOT-K are reliable and valid tools to assess pain in nonverbal patient and thus, are recommended for the assessment of the pain in nonverbal patients.

• Structural Engineering and Mechanics
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• 제75권4호
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• pp.415-424
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• 2020

Recently, many structural damage detection (SDD) methods have been proposed to monitor the safety of structures. As an important modal parameter, mode shape has been widely used in SDD, and the difference of vectors was adopted based on sensitivity analysis and mode shapes in the existing studies. However, amplitudes of mode shapes in different measured points are relative values. Therefore, the difference of mode shapes will be influenced by their amplitudes, and the SDD results may be inaccurate. Focus on this deficiency, a multi-strategy SDD method is proposed based on the included angle of vectors and sparse regularization in this study. Firstly, inspired by modal assurance criterion (MAC), a relationship between mode shapes and changes in damage coefficients is established based on the included angle of vectors. Then, frequencies are introduced for multi-strategy SDD by a weighted coefficient. Meanwhile, sparse regularization is applied to improve the ill-posedness of the SDD problem. As a result, a novel convex optimization problem is proposed for effective SDD. To evaluate the effectiveness of the proposed method, numerical simulations in a planar truss and experimental studies in a six-story aluminum alloy frame in laboratory are conducted. The identified results indicate that the proposed method can effectively reduce the influence of noises, and it has good ability in locating structural damages and quantifying damage degrees.

• Journal of Chest Surgery
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• 제28권6호
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• pp.542-548
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• 1995

The goal of this study is to develop an effective control system for cardiac output regulation based upon the preload and afterload conditions without any transducers and compliance chambers in the moving actuator type total artificial heart. Motor current waveforms during the actuator movement are used as an input to the automatic control algorithm. While the current waveform analysis is performed, the stroke length and velocity of the actuator are gradually increased up to the maximum pump output level. If the diastolic filling rate of either right or left pump begins to exceed the venous return, atrial collapse will occur. Since the diastolic suction acts as a load to the motor, this critical condition can be detected by analyzing the motor current waveforms. Every time this detection criterion is met, the control algorithm decreases the stroke velocity and length of the actuator step by step just below the critical detection level. Then, they start to increase. In this way the maximum pump output under given venous return can be achieved. Additionally the control algorithm provides some degree of afterload sensitivity. If the aortic pressure is detected to exceed 120 mmHg, the stroke length and velocity decrease in the same way as the response to the preload. Left-right pump output balance is maintained by proper adjustment of the asymmetry of the stroke angle. In the mock circulatory test, this control system worked well and there was a considerable range of stroke volume difference with adjustment of the asymmetry value. Two ovine experiments were performed. It was confirmed that the required cardiac output regulation according to the venous return could be achieved with adequate detection of diastolic function, at least in the in vivo short-term survival cases[2-3 days . We conclude that this control algorithm is a promising method to regulate cardiac output in the moving actuator type total artificial heart.

• 복식
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• 제24권
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• pp.217-233
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• 1995

The ultimate purpose of this study is to suggest the most effective marketing strategy for the clothing consumer market based on the new generation consumer's clothing selection behavior analysis. In this thesis, it is appempted to make a progress in the new gen-eration consumer's clothing life style types, in clothing purchase behavior analysis among the clothing life style, and also in the marketing strategy for marketers. The subjects selected for the final analysis are 412 the new gerneration women of age 20 thru 34 in seoul and satellite town area. Data were processed the spss package program. As for the analytic method, factor analysis, clustering analysis, XCross-tubulation, F-test with ANOVA, frequency and percentage were applied in the survey. The major findings are as following : life style is classified into four types : The characteristic fashion-directory type(25.7%) ; The reason traditional type(9.0%) ; The sen-sitivity fashion-following type(11.0%) ; The community brand-conscious type(54.3%). 2 Clothing life style types characteristic of the new generation consumer proved that clothing life style types are a significant difference according to the life style, the fashion consciousness and the average monthly spend-ing on clothing. 3. There is an important discrimination according to the clothing life style types in their clothing purchase behavior such as infor-mation usage, clothing choice criterion and brand loyalty. 4. Based on the result of our analysis and the review of literature, the marketing strategy is suggested that characteristic and new design development is efficient way to consumer's purchase need. Therefore apparel industary which pursue an added value must frame marketing strategy on the basis of the target consumer's sensitivity characteristic according to the life style and fashion consciousness.

• Structural Engineering and Mechanics
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• 제22권6호
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• pp.665-683
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• 2006

The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatly influenced by the properties of constitutive materials, the laminate structures, and load conditions etc, accompanied by many uncertainty factors. So the reliability study on FRP is an important subject of research. Many achievements have been made in reliability studies based on the probability theory, but little has been done on the roles played by fuzzy variables. In this paper, a fuzzy reliability model for FRP laminates is established first, in which the loads are considered as random variables and the strengths as fuzzy variables. Then a numerical model is developed to assess the fuzzy reliability. The Monte Carlo simulation method is utilized to compute the reliability of laminas under the maximum stress criterion. In the second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of the fact that there may exist a series of states between the failure state and the function state, a fuzzy assumption for the structure state together with the probabilistic assumption for strength parameters is adopted to construct the GFRM of composite materials. By defining a generalized limit state function, the problem is converted to the conventional reliability formula that enables the first-order reliability method (FORM) applicable in calculating the reliability index. Several examples are worked out to show the validity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivity analysis shows that some of the mean values of the strength parameters have great influence on the laminated composites' reliability. The differences resulting from the application of different failure criteria and different fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, and can provide an effective and synthetic method to evaluate the reliability of a system with different types of uncertainty factors.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7141-7148
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• 2014

Background: Oral squamous cell carcinoma (OSCC) is an important malignancy throughout the world; early detection is an important criterion for achieving high cure rate. Out of the many reported markers for OSCC, this study validated the efficacy of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in differentially diagnosing premalignant oral lesions and OSCC. Also, the study aimed to correlate the levels of salivary and serum TNF-${\alpha}$ with clinicopathologic factors. Materials and Methods: A prospective experimental laboratory study was designed. Serum and salivary samples from 100 subjects in each group of healthy control, premalignant disease (PMD) and OSCC were collected for the study following appropriate exclusion and inclusion criteria. Serum and salivary level of TNF-${\alpha}$ was analysed by enzyme linked immunosorbent assay. The data obtained were subjected to appropriate statistical analysis. Results: Increased level of both serum and salivary TNF-${\alpha}$ was observed in OSCC subjects compared to healthy control and PMD group. Receiver operator characteristic curve analysis and area under curve values showed high specificity and sensitivity for salivary TNF-${\alpha}$ in differentiating OSCC from PMD and healthy controls. There was significant increase in TNF-${\alpha}$ level in moderately and poorly differentiated lesion compared to well differentiated lesion and in stage IV of clinical stage. A positive correlation was observed only with histological grading of OSCC and TNF-${\alpha}$. Conclusions: Salivary TNF-${\alpha}$ is proved to be superior for detecting OSCC. Increase in TNF-${\alpha}$ with histological grading and clinical staging suggests a role in prognosis.

• 대한조선학회논문집
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• 제38권1호
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• pp.116-122
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• 2001

본 논문에서는 화재안전공학에서 사용되는 모델링 기법과 통계자료들을 검토하고 구조 신뢰성 분야의 확률론적 안전도 평가방법을 도입하여 선박에 대한 방화설계나 선급 규정을 정량적으로 평가하는 방법을 마련하였다. 본 논문에서 개발된 FSEM(Fire Safety Evaluation Module)은 화재안전도의 척도로서 마지막으로 대피하는 사람의 사망확률을 산정하는 프로그램이며, 이를 이용해서 규정에 의한 방화설비를 갖춘 소규모의 화재실에서 대피자에 대한 사망확률을 추정해 보았고, 민감도 해석을 통해 선박에 대한 정량적인 화재안전 평가에의 적용가능성을 검토해 보았다. 계산결과와 검토로부터 선박화재에 대한 새로운 설계지표와 대피상황에서의 인간행동에 대한 폭넓은 연구의 필요성 및 선박의 특수 상황을 고려할 수 있는 새로운 화재진척 모델에 대한 개발이 수행되어야 함을 제시하였다.

• 천문학회보
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• 제35권2호
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• pp.67.2-67.2
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• 2010

We present results of searching for the Very Low Luminosity Objects (VeLLOs; internal luminosity : $L_{int}$ < $0.1(d/140pc)^2\;L\odot$) in the Gould's Belt clouds using observations from 3.6 to 70 micron by the Spitzer Space Telescope. The clouds are California, Chamaeleon I, III, Musca, Lupus V, VI, Scorpius, Serpens, Corona Australis, Cepheus, and IC 5146 having the properties of active low-mass star-forming such as the Taurus cloud. The observing sensitivity of the Spitzer data is estimated to be about $L_{int}\;\geq\;5\times10^{-3}(d/140pc)^2\;L\odot$, a factor of 20 better than that of the Infrared Astronomical Satellite (IRAS). The observing data were processed by the c2d Legacy pipeline. As the criteria to select the VeLLOs, we slightly modified previous ones by Dunham et al. The most important criterion is a flux density at 70 micron that is directly converted to the internal luminosity. Also, we used additional criteria to remove the contamination of evolved stars and extragalaxies which have colors or SEDs very similar to YSOs. We identified a total of 64 new embedded VeLLO candidates with $L_{int}$ < $0.1(d/140pc)^2\;L\odot$, consisting of 8 in California, 15 in Chamaeleon-Musca, 13 in Scorpius-Lupus, 20 in Serpens, 3 in Corona Australis, 3 in Cepheus, and 2 in IC 5146. The classification of the spectral index (${\alpha}$) fitted to the shape of the Ks-24 micron SEDs shows most of VeLLO candidates (89%) are in types of Class I and Flat spectrum. We plot various diagrams based on their 2MASS-Spitzer bands colors and magnitudes to discuss properties of the VeLLOs. This search will lead us new adventure toward a future systematic study of the VeLLOs.

• Journal of Oral Medicine and Pain
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• 제40권2호
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• pp.47-54
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• 2015

Purpose: Besides depression and anxiety, recently pain catastrophizing has been emphasized for an important psychological factor explaining pain response in various pain conditions including temporomandibular disorders (TMDs). The aims of this study were to evaluate pain catastrophizing of TMD patients and to investigate how the level of pain catastrophizing related with clinical variables and psychometric morbidity. Methods: Inclusion criterion was all new TMD patients ${\geq}18$ years old attending the Department of Orofacial Pain and Oral Medicine of Dankook University Dental Hospital (Cheonan, Korea) over three-month period in 2014, who completed questionnaires. The questionnaires included the Brief Pain Inventory (BPI), Pain Catastrophizing Scale (PCS), and Symptom Check List- 90-Revised (SCL-90-R). All of them were examined clinically and diagnosed. Results: One hundred fifty five patients diagnosed as TMDs were participated in this study (mean age of $38.7{\pm}15.2$ years, male:female=1:2.5). Mean PCS score of the patients was 17.3 with standard deviation of 12.6. By the median of the PCS score (i.e., 15), the subjects were categorized into the high (${\geq}15$) and low catastrophizers (<15). Increased pain severity and interference and increased score of psychological features of SCL-90-R were found in the TMD patients with higher level of catastrophizing (p<0.001) and there was weak to moderate correlation between those factors (p<0.05). Difference in catastrophizing level was not found for other variables such as age, gender, duration of pain, education level and types of TMDs. Conclusions: Conclusively, pain catastrophizing of TMD patients relates positively to pain severity and pain interference. In addition to depression and anxiety, pain catastrophizing is positively correlated with variable other psychological morbidity such as somatization, obsessive- compulsive, interpersonal sensitivity, paranoid ideation and psychoticism. Types of TMD diagnosis do not seem to affect catastrophizing level. The results of this study suggest that pain catastrophizing should be emphasized and assessed in the TMD patients.