• Wind and Structures
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• 제36권1호
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• pp.61-73
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• 2023

In this article, a novel structural modal parameters identification methodology is developed to determine the natural frequencies and damping ratios of civil structures based on the symplectic geometry mode decomposition (SGMD) approach. The SGMD approach is a new decomposition algorithm that can decompose the complex response signals with better decomposition performance and robustness. The novel method firstly decomposes the measured structural vibration response signals into individual mode components using the SGMD approach. The natural excitation technique (NExT) method is then used to obtain the free vibration response of each individual mode component. Finally, modal natural frequencies and damping ratios are identified using the direct interpolating (DI) method and a curve fitting function. The effectiveness of the proposed method is demonstrated based on numerical simulation and field measurement. The structural modal parameters are identified utilizing the simulated non-stationary responses of a frame structure and the field measured non-stationary responses of a supertall building during a typhoon. The results demonstrate that the developed method can identify the natural frequencies and damping ratios of civil structures efficiently and accurately.

• Radiation Oncology Journal
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• 제24권4호
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• pp.237-242
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• 2006

목 적: 국소적으로 진행된 비소세포성 폐암에서 예후영향인자를 찾기 위하여 근치적 방사선 치료에 대한 성적을 후향적으로 평가하였다. 대상 및 방법: $1991{\sim}2002$년에 걸쳐 본원에서 방사선치료를 받은 stage IIIB 비소세포성 폐암 환자 216명의 의무기록을 후향적으로 분석하였다. 완전관해와 부분관해를 반응군(response group), 불변 및 진행성질환을 무반응군(non-response group)으로 묶어 분류하였다. 결 과: 근치목적의 방사선치료를 시행한 총 140명의 환자 중 방사선단독치료를 받은 환자는 68명, 항암화학제와 병용요법을 시행한 환자는 72명이었다. 계획된 방사선치료가 완료된 것은 단독에서는 30예, 병용요법에서는 39예였다. 중앙생존기간은 방사선 단독치료군에서는 4.6개월, 병용요법군에서는 9.9개월이었다. 1년, 2년 및 3년 생존율이 방사선 단독치료군에서는 13.3%, 3.3%, 0%였으며, 항암화학제 병용요법군에서는 각각 35.9%, 20.5%, 15.4%였다(p<0.001). 반응군에서 방사선 단독으로 치료한 환자는 중앙생존기간 7.2개월, 항암화학제 병용치료환자는 16.5개월이었고, 무반응군에서 단독치료 환자는 4.4개월, 병용치료환자는 6.7개월이었다(p=0.001). 치료반응과 항암화학요법의 병용이 전체생존율에 영향을 주었다(p<0.001). Grade 3 이상의 심한 합병증은 방사선 단독요법에서 2예(6.7%), 항암화학 병용요법에서 7예(17.9%)였다. 결 론: Stage IIIB 비소세포성 폐암에서 방사선치료와 더불어 항암화학치료를 병용했을 때, 방사선단독요법에 비해 치료반응률과 생존율이 더 높았다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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• pp.91-94
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• 2001

In the frequency response analysis using a modal method, it is very important to determine the number of modes involved with the formulation of a frequency response function. Most engineers are inclined to determine mode truncation with their experience. But it is difficult for non-experts to decide the mode truncation reasonably in many problems of dynamic analyses. In this study, fuzzy theory is used to standardize the empirical determination of mode truncation so that not only the experts but also non-experts can decide a proper mode truncation easily. Fuzzy rule base is based on the simulation results using finite element method. Numerical simulations show that the developed mode truncation method is a very effective method to choose the number of the considered modes.

• 대한수의학회지
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• 제14권2호
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• pp.207-210
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• 1974

Pharmacological investigation was performed in chickens which were pretreated with reserpine. Transmural stimulations were given to the isolated jejunum of chickens and studied the responses and the effects of dibenamine, propranolol, atropine and tetrodotoxin on them. The results obtained were summerized as follows: 1. Three different patterns of response were obtained from the isolated jejunum of non-treated chickens after giving them transmural stimulation. The first pattern was contraction followed by relaxation, the second pattern was contraction only and the third pattern was relaxation only. 2. The transmural stimulation of the jejunum preparations evoked relaxation while the periarterial stimulation evoked contraction in the reserpinized chick. 3. The relaxation response to the transmural stimulation was not affected by the pretreatment with dibenamine, propranolol and atropine. 4. The relaxation response to the transmural stimulation was abolished by tetrodotoxin. The results obtained in these studies indicate that the relaxation response to the transmural stimulation is due to non-adrenergic inhibitory fibers.

• Communications for Statistical Applications and Methods
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• 제18권3호
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• pp.367-376
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• 2011

BLS 가중치보정법은 사업체 조사 시 발생한 무응답 및 이상점을 처리하기 위해 사용하는 가중치 보정방법중의 하나이다. 최근의 연구에 의하면 총계 추정에 있어 BLS 무응답 가중치보정법의 결과가 비추정법을 사용한 대체 결과와 일치하는 것으로 알려졌다. 본 논문에서는 이상점과 무응답이 동시에 있는 경우, BLS 무응답 가중치보정법을 비추정 대체법으로 바꾸어 총계를 추정하는 새로운 방법을 제안하였다. 매월 노동 통계 자료를 이용한 모의 실험을 통하여 제안된 방법의 우수성을 확인하였다.

• International Journal of Human Ecology
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• 제7권1호
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• pp.25-36
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• 2006

The purpose of this study was to investigate and compare visiting intentions by positive and negative Word-of-Mouth (WOM) and/or information of beauty shop between female college students and adult women. Data were collected from 500 consumers (250 from female students and 250 adult women) and was analyzed by using frequencies, factor analysis, t-tests and multiple regression utilizing SPSS/PC+. The findings revealed positive experience factors to prudent service, time saving/consideration for customer's position, kindness/operating system in waiting time, added services, employees' attitudes, excellent beauty and response skill, rational price and recall system/remind for customer. The negative experiences were inconsistent service, operators' convenient service, irrational price/poor skill/non-recall, non-customer central service, inappropriate face-to-face management to customer. Also, the results showed that the positive WOM information such as prudent service, time saving/consideration for customer's position, excellent beauty and response skill and rational price had influence on the visiting intention in case of female college students. The negative WOM information like non-customer central service, had influence on the visiting intention in cases of adult women.

• 대한의생명과학회지
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• 제23권3호
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• pp.215-222
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• 2017

Obesity has been directly associated with the development of hypertension and cardiovascular disease. The purpose of this study was to investigate the blood pressure response during graded exercise test in obese adults. 189 subjects (age: $47.96{\pm}10.23$) were assigned to two groups: non-obese group (N=105, BMI: $22.05{\pm}1.57$, waist circumference: $76.90{\pm}6.17$) and obese group (N=84, BMI: $26.96{\pm}2.51$, waist circumference: $88.29{\pm}6.41$). The subjects underwent health screening and exercise treadmill test from January 2012 to December 2014. Graded exercise test was performed according to the Bruce protocol. Exercise duration (P=0.046) and METs (P=0.015) were significantly lower in obese group than non-obese group. There was no difference in the rate of change in blood pressure response between obese group and non-obese group during exercise, and the recovery rate of systolic blood pressure was delayed in the obese group compared to non-obese group in the first recovery period (P=0.020). The significant factors of increasing rate of change in maximum systolic blood pressure was waist (P=0.046) and hip circumference (P=0.008). In conclusion, these results demonstrate that, for hypertension prevention in obese adults, waist and hip circumference levels should be managed within normal range.

• Computers and Concrete
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• 제9권3호
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• pp.195-213
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• 2012

This paper presents the investigation of the stochastic responses of seismically isolated bridges subjected to spatially varying earthquake ground motions including incoherence, wave-passage and site-response effects. The incoherence effect is examined by considering Harichandran and Vanmarcke coherency model. The effect of the wave-passage is dealt with various wave velocities in the response analysis. Homogeneous firm, medium and soft soil conditions are selected for considering the site-response effect where the bridge supports are constructed. The ground motion is described by filtered white noise and applied to each support points. For seismic isolation of the bridge, single and double concave friction pendulum bearings are used. Due to presence of friction on the concave surfaces of the isolation systems, the equation of motion of is non-linear. The non-linear equation of motion is solved by using equivalent linearization technique of non-linear stochastic analyses. Solutions obtained from the stochastic analyses of non-isolated and isolated bridges to spatially varying earthquake ground motions compared with each other for the special cases of the ground motion model. It is concluded that friction pendulum systems having single and double concave surfaces have important effects on the stochastic responses of bridges to spatially varying earthquake ground motions.

• Animal cells and systems
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• 제4권4호
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• pp.337-340
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• 2000

The photosynthetic and stomatal responses of several woody plants (Powlonia coreana, Firmiana simplex, Quercus acutissima Q. variabilis and Q. serrata) to SO$_2$ were investigated in order to understand their ecophysiological tolerance to $SO_2$ Of the plants, P, coreana showed the largest reduction in its photosynthesis in response to exposure of 0.4 ppm $SO_2$ for 20 h. Fumigation of 0.7 ppm $SO_2$ for 20 h caused complete leaf necrosis of P. coreana and f simplex, which made them unavailable for the measurement of photosynthesis. Q. variabilis exhibited the smallest reduction in photosynthesis following exposure of 0.7 ppm $SO_2$ for 20 h. Both stomatal- and non-stomatal inhibition of the plants by $SO_2$ were determined according to equations by lkeda et at. (1992). When exposed to 0.4 ppm $SO_2$ for 20 h, F. simplex and P. coreana showed the lowest stomatal and non-stomatal inhibition, respectively, while Q. variabilis and Q. serrata exhibited the lowest stomatal and non-stomatal inhibition, respectively, in response to 0.7 ppm $SO_2$ for 20 h. The data are discussed with regard to resistance mechanisms of other plants to $SO_2$ exposure and implications for restoration of declined Korean forests.

• 생물정신의학
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• 제10권1호
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• pp.70-79
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• 2003

Object : Currently, the alteration of cytokine system has been known to play an important role in regard to depressive symptom. We focused on the relationship between immunological parameters and clinical improvement in major depressive disorder. Method : Data were collected on 26 patients with major depressive disorder using a 8-week prospective follow-up design. After 8-week treatment period with fluoxetine, patients were classified into a response group and a non-response group according to their psychopathological outcome as evaluated by Hamilton Depression Rating Scale. The differences of the immunological parameters between pre-treatment phase and post-treatment phase were compared among patients. The difference of those was also compared within each phase among them. The relationship between socio-demographic variables, depression, cytokine, mononuclear cells was examined by correlation analysis. Multiple regression analyses were performed to explore the predictors of clinical improvement of major depressive disorder. Result : Pre-treatment levels of IL-$1{\beta}$ in the response group were significantly higher than those in the non-response group. Pre-treatment levels of IL-$1{\beta}$ of all patients and in the response group were positively correlated with pre-treatment monocyte counts. Patients with subsequent remission showed significantly lower IL-6 values at baseline than those with non-response. Post-treatment values of IL-6 did not differ significantly among the patients. The correlation test showed more frequent relations among cytokines and mononuclear cells in the response group than in the non-responder group. Especially, serum level of IL-6 in pre-treatment phase was only significantly correlated with HAMD score after 8-week treatement phase, while other cytokines and mononuclear cells were not. Pretreatment level of IL-6 was of paramount importance in predicting clinical improvement of depressive symptom. Conclusion : The immune system of major depressive disorder patients might dichotomize the patients into subsequent responders and non-responders. Immune system might be of great influence on the clinical improvement of major depressive disorder. The mode of interaction between depression and cellular immune function and the mediators responsible for the cytokine production need to be studied further.