• Structural Engineering and Mechanics
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• 제49권2호
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• pp.203-223
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• 2014

The extensive use of prestressed reinforced concrete (PSC) highway bridges in marine environment drastically increases the sensitivity to both fatigue-and corrosion-induced damage of their critical structural components during their service lives. Within this scenario, an integrated method that is capable of evaluating the fatigue reliability, identifying a condition-based maintenance, and predicting the remaining service life of its critical components is therefore needed. To accomplish this goal, a procedure for fatigue reliability prediction of PSC highway bridges is proposed in the present study. Vehicle-bridge coupling vibration analysis is performed for obtaining the equivalent moment ranges of critical section of bridges under typical fatigue truck models. Three-dimensional nonlinear mathematical models of fatigue trucks are simplified as an eleven-degree-of-freedom system. Road surface roughness is simulated as zero-mean stationary Gaussian random processes using the trigonometric series method. The time-dependent stress-concentration factors of reinforcing bars and prestressing tendons are accounted for more accurate stress ranges determination. The limit state functions are constructed according to the Miner's linear damage rule, the time-dependent S-N curves of prestressing tendons and the site-specific stress cycle prediction. The effectiveness of the methodology framework is demonstrated to a T-type simple supported multi-girder bridge for fatigue reliability evaluation.

• 대한치과교정학회지
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• 제24권3호
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• pp.649-658
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• 1994

The purpose of this study was to evaluate the association between incisor root resolution and sex, age, extraction, the magnitude and direction of tooth movement. The sample consisted of 189 randomly selected orthodontic patients, receiving standard edgewise orthodontic treatment in three private orthodontic onces at San Francisco. Pre-treatment and post-treatment periapicals and cephalometric radiographs were digitized. Measurements and superimpositions were made utilizing a computerized cephalometric analysis program. The variables were statistically analyzed. The results were as follows: 1. Mean apical root resorption values were $0.77{\pm}2.08mm$ for upper right central incisor, $0.88{\pm}2.11mm$ for upper left central incisor, $-0.05{\pm}2.09mm$ for lower right central incisor and $0.11{\pm}1.85mm$ for lower left central incisor. Apical root resorption of upper incisor was greater than lowers. 2. No correlation was found between sex and apical root resorption. 3. Apical root resorptions in adolescents were smaller than those in adults. 4. Apical root resorption was not affected by extraction. 5. Apical root resorption values of upper incisor were correlated to the horizontal and vertical movement of apex; Apical root resorption values of lower incisor were correlated to the vertical movement of apex.

• Strategy21
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• 통권31호
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• pp.164-189
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• 2013

Last December, the Abe government came back, and it is critical core of Northeast Asia. They visited to Yasukuni Shrine, denied to Korea's invasion and they are denying all of their invasion history. I'm afraid they want to take Dokdo. Dokdo is Korean territory, but Japan politics assert it belongs to them. To make matters worse, they are waiting an opportunity to invade. Ministry of Foreign Affair blue paper and Ministry of Defense white paper have claimed Dokdo as Japanese territory, and many right wing politicians are taking part in the Cabinet. Liberal Democratic Party of Japan is becoming more right wing politicians than before by Japan Restoration Party, and the others also have more right wing ideologies. It can't control Japan right wing political parties. They finally aim to take Dokdo. In this situation, we have to defend Dokdo. Japan must be very important partner for our nation's development. But it is necessary to trust between two countries. Dokdo is effective controlled by Korea. It is the best way how to keep Dokdo. During Dokdo is effective controlled by Korea, the Japanese Government has limited Dokdo's ownership. Now we don't have any way to keep Dokdo except more effective control. We have strategies about Japanese claim of Dokdo's ownership as follows. First, we can overpower Japan right wing politics as Japan conscientious force's ideology. Second, Japan politics say to Dokdo's ownership is based on The San Francisco Treaty. But it is not right. Third, we have to exchange a lot of local government and civic society in Japan. Finally, we must prepare thoroughly to bring the matter to the International Court of Justice.

• 한국환경농학회지
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• 제15권2호
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• pp.246-261
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• 1996

현재 사용되고 있는 유기합성 농약의 중요한 부분을 차지하고 있는 유기인계 농약의 대부분은 분자에 황 원자를 포함하고 있으며 환경이나 생체 내에서 대사되어 활성화 되거나 무독화 된다. 이에 관련된 다양한 반응 중 산화반응이 주요 대사반응으로 여겨지는데 이산화대사에 의해 생성된 대사물의 특성도 중요하거니와 반응 중 생성되는 반응성 중간체에 대한 연구는 대사반응의 경로 및 기작 구명에 필수적이고 농약의 독성학적 특성을 이해하는 데에 중요한 위치를 차지하고 있다. 본 총설은 유기인계 농약을 중심으로 관련 유기인 화합물을 대상으로 산화대사 반응 중 생성되는 반응성 중간체에 대한 연구들을 그 구조구명과 반응 기작면에서 다루었다.

• Journal of Pharmaceutical Investigation
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• 제24권3호spc1호
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• pp.41-47
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• 1994

The effect of Azone and ethanol on the electrical properties of human and hairless mouse skin was studied and the results were compared. The complex electrical impedance was measured as a function of frequency, and resistance and capacitance were determined from Nyquist plot. After the treatment of human-heat separated epidermis with Azone, contrary to the expectation, resistance increased about 60% and it did not change with time. Capacitance also increased; immediately after the treatment, it was about 110% of pretreatment value and it increased further with time. On the other hand, when hairless mouse skin was treated with Azone, marked changes occured; resistance fell almost to the value of bathing medium itself and capacitance increased to about 200% of its pretreatment value. Similar result were obtained when hairless mouse skin was treated with 100% ethanol. The results suggest that there are differences in the strength of barrier properties of stratum corneum (SC) between human and hairless mouse skin. Overall, the results provide further mechanistic insight into ion conduction through the skin and into the role of SC lipids in skin capacitance.

• Steel and Composite Structures
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• 제19권4호
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• pp.811-827
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• 2015

This paper presents a probabilistic investigation of American and European specifications (i.e., AISC and Eurocode 4) for square concrete-filled steel tubular (CFT) stub columns. The study is based on experimental results of 100 axially loaded square CFT stub columns from the literature. By comparing experimental results for ultimate loads with code-predicted column resistances, the uncertainty of resistance models is analyzed and it is found that the modeling uncertainty parameter can be described using random variables of lognormal distribution. Reliability analyses were then performed with/without considering the modeling uncertainty parameter and the safety level of the specifications is evaluated in terms of sufficient and uniform reliability criteria. Results show that: (1) The AISC design code provided slightly conservative results of square CFT stub columns with reliability indices larger than 3.25 and the uniformness of reliability indices is no better because of the quality of the resistance model; (2) The uniformness of reliability indices for the Eurocode 4 was better than that of AISC, but the reliability indices of columns designed following the Eurocode 4 were found to be quite below the target reliability level of Eurocode 4.

• Structural Engineering and Mechanics
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• 제62권5호
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• pp.631-642
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• 2017

Accurate actuator tracking plays an important role in real-time hybrid simulation (RTHS) to ensure accurate and reliable experimental results. Frequency-domain evaluation index (FEI) interprets actuator tracking into amplitude and phase errors thus providing a promising tool for quantitative assessment of real-time hybrid simulation results. Previous applications of FEI successfully evaluated actuator tracking over the entire duration of the tests. In this study, FEI with moving window technique is explored to provide post-experiment localized actuator tracking assessment. Both moving window with and without overlap are investigated through computational simulations. The challenge is discussed for Fourier Transform to satisfy both time domain and frequency resolution for selected length of moving window. The required data window length for accuracy is shown to depend on the natural frequency and structural nonlinearity as well as the ground motion input for both moving windows with and without overlap. Moving window without overlap shows better computational efficiency and has potential for future online evaluation. Moving window with overlap however requires much more computational efforts and is more suitable for post-experiment evaluation. Existing RTHS data from Network Earthquake Engineering Simulation (NEES) is utilized to further demonstrate the effectiveness of the proposed approaches. It is demonstrated that with proper window size, FEI with moving window techniques enable accurate localized evaluation of actuator tracking for real-time hybrid simulation.

• Journal of Pharmaceutical Investigation
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• 제17권2호
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• pp.55-60
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• 1987

WR 2721 (S-2-(3-aminopropylaminoethylphosphorothioate) is a radioprotective drug that is now undergoing clinical trials in the United States and Japan. a liquid chromatographic electrochemical method for the determination of WR 2721 an WR 3689 [S-2-(3-methylaminopropylamino)ethylphorothioate] in human plasma was developed in this study. This method includes the use of a Hg/Au electrochemical detector and a cyano column for the direct measurement of WR 2721 and WR 3689 in plasma. An analog of WR 2721, WR 149846 was used as an internal standard. WR 2721 and WR 3689 could be well separated from the solvent front, with a mobile phase of acetonitrile-water (20:80), 0.1M acetic acid and 1.2 mM sodium octane sulfonate. This method was shown to be precise. Both intra-day and inter-day results were within 10% CV. Also, sample preparation was fairly simple. Since WR 2721 and WR 3689 were unstable at room temperature, it was essential to use an automatic sample processor with a refrigerator, especially for carrying out routine analyses.

• 대한간호학회지
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• 제42권7호
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• pp.1095-1104
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• 2012

Purpose: The purpose of this study was to investigate the contribution of actual cardiovascular disease (CVD) risk, as well as, individual, psychosocial, and work-related factors as predictors of CVD risk perception among Korean blue-collar workers. Methods: The participants were 238 Korean blue-collar workers who worked in small companies. Data were collected through a survey; anthropometric and blood pressure measures; and blood sampling for lipid levels. Results: Blue-collar workers had high actual CVD risk and low CVD risk perception. The significant predictors of risk perception included perceived health status, alcohol consumption, knowledge of CVD risk, actual CVD risk, decision latitude, and shift work. The model explained 26% of the variance in CVD risk perception. Conclusion: The result suggests when occupational health nurses are giving routine health examination in small companies, they can enhance CVD risk perception in blue-collar workers by providing essential information about CVD risk factors and personal counseling on the individual worker's CVD risk status.

• International Journal of Human Ecology
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• 제8권1호
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• pp.39-51
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• 2007

This study compares the buying patterns of American and Korean female college students in relation to their self-concept. It was implemented through self-administered questionnaires which were back translated for validity. Respondents comprised 730 female students majoring in fields related to clothing and textiles: 307 U.S. students were located in the Northeast, West, and Southwest, and 423 Korean students were at four universities in Seoul. Likert scales were used for most measures, with 1 = never or very unimportant, and 5 = always or very important. Personal self-concept was measured on the basis of Won-Shik Jung's Standardized Self-concept the Test and Tennessee Self Concept Scale. Data were analyzed by descriptive statistics and t-tests. Some clear differences between the two countries emerged. Marketers targeting American consumers should pay more attention to practicality and service, and for Koreans, more symbolic meaning of products and store displays, since these are important to them. Self-concept was somewhat related to purchasing behavior, but more study should be done before applying findings to marketing concepts.