• 대한기계학회논문집A
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• 제31권11호
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• pp.1059-1068
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• 2007

Nonlinear response structural optimization is performed using equivalent loads (NROEL). Nonlinear response optimization is extremely cost because many nonlinear analyses are required. In NROEL, the external loads are transformed to the equivalent loads (EL) for linear static analysis and linear response optimization is carried out based on the EL in a cyclic manner until the convergence criteria are satisfied. EL is the load set which generates the same response field of linear analysis as that of nonlinear analysis. The primitive from of theory has been published. In this research, the theory is investigated with large scale example problems. Four examples are solved by using NROEL. Conventional optimization with sensitivity analysis using the finite difference method (FDM) is also applied to the same examples. Moreover, response surface optimization method is applied to the last two examples. The results of the optimizations are compared. In nonlinear response optimization of large scale problems, hundreds (or even thousands) of nonlinear analyses are expected to satisfy the convergence criteria. However, in nonlinear response optimization using equivalent loads, only tens of nonlinear analyses are required. The results are discussed and the usefulness of NROEL is presented.

• 해양환경안전학회지
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• 제5권2호
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• pp.1-14
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• 1999

To find characteristics and areas of greater risk of oil spill at the coastal waters in Korea, some of risk factors were analyzed with historical data of oil spill and marine traffic. As a result, it is characterized that frequency of oil spill is increasing year by year and greatest percentage of spill source is fishing boat. It is proposed that the ports of Ulsan, Yeosu, Incheon and Pusan will be designated as primary area of risk as they have a higher risk of oil spills and its response authority is required to maintain appropriate regional response capability for prompt and effective response to a future spill incident. In addition, the regional response equipments at Ulsan are examined under a assumption of a medium size spill and it is found that the use of chemical dispersant can be an alternative when mechanical containment and recovery is not feasible in this area, and the existing response equipments may be appropriate to address that size of spill. However, the response authority is required to maintain more numbers of stronger boom for unsheltered waters and more quantity of concentrate dispersant to disperse all spilled oils on the water, furthermore the response authority should be prepared for a possible future catastrophic spill with sufficient equipments.

• Wind and Structures
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• 제30권3호
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• pp.275-288
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• 2020

High-rise buildings are very slender and flexible. Their low stiffness values make them vulnerable to horizontal loads, such as those associated with wind or earthquakes. For high-rise buildings, the threat to serviceability caused by wind-induced vibration is an important problem. To estimate the serviceability under wind action, the response acceleration of a building at the roof height is used. The response acceleration is estimated by the same wind speed at all wind directions. In general, the effect of wind direction is not considered. Therefore, the response accelerations obtained are conservative. If buildings have typical plans and strong winds blow from relatively constant wind directions, it is necessary to account for the wind direction to estimate the response accelerations. This paper presents three methods of evaluating the response accelerations while considering the effects of wind direction. These three serviceability evaluation methods were estimated by combining the wind directional frequency data obtained from a weather station with the results of a response analysis using wind tunnel tests. Finally, the decrease in the efficiencies of the response acceleration for each serviceability evaluation method was investigated by comparing the response acceleration for the three methods accounting for wind direction with the response acceleration in which wind direction was not considered.

• 정신신체의학
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• 제4권1호
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• pp.44-53
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• 1996

The present experiment was designed to investigate the effects of behavioral, response to immune function in response to electric footshock in mice. Mice were subjected to electric footshock for 3 days(two sessions a day, 11 times of shock for about 31 minutes a session). The humoral immune response was measured using mice immunized with rat RBC. The cell-mediated immune responses were evaluated by contact hypersensitivity to 2, 4-dinitrofluorobenzene(DNFB) and by phytohemagglutin(PHA)-stimulated splenocytes proliferation assay. In stressed group, electric footshock suppressed significantly anti-rat RBC antibody production(p<0.05), but enhanced significantly $T_{48}$ relative to $T_{24}$ in contact hypersenstivry (P<.01) and T-cell proliferation response(P<.05) by PHA stimulation elative to control group. T-cell proliferation response by PHA stimulation was significantly correlated to the movement than the sensitivity and coping behavior in the mouse, in response to the electric footshock. These data supper the importance of behavioral response in stress-induced changes of immune functions.

• 대한영양사협회학술지
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• 제26권4호
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• pp.278-288
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• 2020

This study examined the effects of response-facilitating factors(Food-related Knowledge, Response-Efficacy, and Self-Efficacy) and response-inhibiting factors(Severity, Vulnerability, and Consumer Stress) on the consumer' behavior intention based on protection motivation theory, which explains the behavioral change to protect oneself. This study was conducted to reduce the customers' concerns regarding food safety accidents and introduce ways to make them more interested in food safety. A sample of 225 adults over 19 years of age was collected in February 2018 through a self-administered questionnaire. The results of the cognitive mediation process of protective motivation theory showed that the consumers' knowledge and self-efficacy which are response-facilitating factors, positively influence the behavioral intention. Severity and consumer stress were response-inhibiting factors. On the other hand, response-efficacy, which is a response-facilitating factor, and vulnerability, which is a response-inhibiting factor, did not influence the behavioral intention. Therefore, severity and consumer stress are response-inhibiting factors. The results were analyzed as a result of a behavioral change to protect oneself from food safety accidents. The applicability of the theory of protection motivation on the topic of food safety was also confirmed.

• 한국소음진동공학회논문집
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• 제21권5호
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• pp.400-407
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• 2011

The suggested method of previous Son's study dichotomized subjective response data to modeling noise exposure-response. The method used maximum liklihood estimation instead of least square estimation and the noise exposure-response curve of the study was logistic regression analysis result. The method was originated to modeling community response rate such as %HA or %A. It can be useful when the subjective response was investigated based on predicted noise level. It is difficult to measure the single source emitting noise such as railway because various traffic noise sources combined in our life. The suggested method was adopted to model in this study and railway noise-exposure response curves were modeled because the noise level of this area was predicted data. The data of this study was used by previous Ko's paper but he dealt the area as combined noise area and divided the data by dominant noise source. But this study used all data of this area because the annoyance response to railway noise was higher than other noise according to the result of correlation analysis. The trend of the %HA and %A prediction model to train noise of this study is almost same as the model based on measured noise of previous Lim's study although the investigated areas and methods were different.

• Structural Engineering and Mechanics
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• 제64권2호
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• pp.259-270
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• 2017

The stochastic vibration response of the sandwich beam with the nonlinear adjustable visco-elastomer core and supported mass under stochastic support motion excitations is studied. The nonlinear dynamic properties of the visco-elastomer core are considered. The nonlinear partial differential equations for the horizontal and vertical coupling motions of the sandwich beam are derived. An analytical solution method for the stochastic vibration response of the nonlinear sandwich beam is developed. The nonlinear partial differential equations are converted into the nonlinear ordinary differential equations representing the nonlinear stochastic multi-degree-of-freedom system by using the Galerkin method. The nonlinear stochastic system is converted further into the equivalent quasi-linear system by using the statistic linearization method. The frequency-response function, response spectral density and mean square response expressions of the nonlinear sandwich beam are obtained. Numerical results are given to illustrate new stochastic vibration response characteristics and response reduction capability of the sandwich beam with the nonlinear visco-elastomer core and supported mass under stochastic support motion excitations. The influences of geometric and physical parameters on the stochastic response of the nonlinear sandwich beam are discussed, and the numerical results of the nonlinear sandwich beam are compared with those of the sandwich beam with linear visco-elastomer core.

• 대한불안의학회지
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• 제11권1호
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• pp.33-37
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• 2015

Objective : Impaired response inhibition has been suggested to play an important role in the pathophysiology of obsessive-compulsive disorder (OCD). The aim of this study was to evaluate the response inhibition in patients with OCD, by using the Go/NoGo paradigm, and to better understand its associations with clinical symptoms. Methods : The participants included 63 OCD patients and 80 healthy volunteers matched in age and sex. response inhibition was evaluated using computerized Go/NoGo task, in which their commission error rates, omission error rates, and mean response times were measured. The severity of clinical symptoms in the OCD patients was assessed using Montgomery-Asberg Depression Scale and Yale-Brown Obsessive Compulsive Scale. Result : OCD patients showed significantly impaired inhibition and higher omission errors rates despite their slower response time, compared to normal controls. Clinical symptoms were not correlated with commission errors and omission errors. Conclusion : The present results indicate that impairment in response inhibition may play a critical role in the pathophysiology of OCD as a trait. These findings suggest that deficit of response inhibition may contribute to developing and maintaining clinical symptoms such as compelling need to repeat certain actions in patients with OCD.

• 대한핵의학회지
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• 제13권1_2호
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• pp.31-36
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• 1979

The TRH stimulation test was known as a highly diagnostic method in hypothalamopituitary disorders. To evaluate the location and the extension of the lesion, we estimated TSH response to TRH test in 27 patients. Correlation between volume of sella and TSH response was also studied. The results obtained were as follows: 1. In Sheehan's syndrome, TSH response after TRH test were not observed in all of 12 patients. 2. All 2 acromegaly patients showed normal TSH response. 3. In 4 cases of chromophobe adenoma, 2 cases showed no TSH response. In 2 responded cases, one patient whose tumor mass extended to suprasella region was hypothyroid state. 4. In craniopharyingioma 3 cases, the tumor which extended to intrasella showed hypothyroid and no TSH response. 5. Correlation between volume of sella and TSH response were valuable in 2 cases, but no diagnostic significance. 6. In diabetes inspidus, TSH response were all absent. 7. In primary amenorrhea, TSH response observed in 1 case, which conformed with isolated FSH deficiency.

• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.167-174
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• 2006

Two typical responses have been documented for flatfish when they encounter the ground gear of bottom trawls: herding response and falling back response. These two responses were analyzed from video recordings of fish and were characterized by time sequences for four parameters: swimming speed, angular velocity, acceleration, and distance between the fish and the ground gear. When flatfish displayed the falling-back response, absolute values of the three swimming parameters and their deviations were significantly higher than those during the herding response. However, the swimming parameters were not dependent on the distance between the flatfish and the ground gear, regardless of which response occurred. The dominant periods for most of the movement parameters ranged from 2.0 to 3.7 s, except that no periodicity was observed for swimming speed or angular velocity during the falling-back response. However, variations in the four parameters during the falling -back response revealed greater irregularity in periodicity and higher amplitudes. This complex behavior is best described as a chaos phenomenon' and is discussed as the building block for a model predicting the responses of flatfish to ground gear as part of the general understanding of the fish capture process.