• Journal of Korean Society of Steel Construction
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• v.17 no.1 s.74
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• pp.103-113
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• 2005

In the present study, the Direct Inelastic Design (DID) for steel structures developed in the previous study was improved to expand it applicability. The proposed design method can perform inelastic designs that address the design characteristics of steel structures: Group member design, discrete member sizes, variation of moment-carrying capacity according to axial force, connection types, and multiple design criteria and load conditions. The design procedure for the proposed method was established, and a computer program incorporating the design procedure was developed. The design results from the conventional elastic method and the DID were compared and verified by the existing computer program for nonlinear analysis. Compared with the conventional elastic design, the DID addressing the inelastic behavior reduced the total weight of steel members and enhanced the deformability of the structure. The proposed design method is convenient because it can directly perform inelastic design by using linear analysis for secant stiffness. Also, it can achieve structural safety and economical design by controlling deformations of the plastic hinges.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.597-606
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• 2019

Due to climate change, coastal areas are being flooded with torrential rain, typhoons, and tsunamis. In addition, non-point source pollutants (NPSs) that accumulated on the ground, streets, and buildings during the dry season are washed off by rain and stormwater runoff, which adds to the damage associated with environmental pollution, e.g., pollution that makes its way into the ocean. Recently, low impact development (LID) has been considered as a means of controlling water circulation and NPSs. In the coastal area, permeable blocks have been constructed mainly to reduce the flood damage caused by waves. Some important design factors that must be considered to ensure long-term performance are the permeability coefficient, clogging, and the efficiency of the removal of total suspended solids (TSS), but currently there are no standardized design criteria or testing techniques that are used worldwide. Herein, we analyzed the permeability coefficient and the TSS removal efficiency tendency according to the permeability area ratio with an easily-detachable, permeable block filled with calcinated yellow soils as the filter media. Our lab-scale tests indicated that, when the permeability area ratio was 25%, the reduction of the permeability coefficient after clogged was 11%, which was a significant decrease compared to other cases. Permeability persistence increased when the permeability area ratio increased from 50% to 75%. The TSS removal efficiency decreased as the permeability area ratio increased. Our pilot-scale test indicated that the TSS removal efficiency was more than 80% higher in all cases. We also found that the permeability persistence was excellent as the permeability area ratio increased, and, in actual construction, it is effective to set 5.3% of the total area as permeable area in terms of permeability and economic feasibility.

• Earthquakes and Structures
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• v.14 no.1
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• pp.1-10
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• 2018

Seismic retrofitting of existing buildings and design of earth-quake resistant buildings are important issues associated with earthquake-prone zones. Use of metallic-yielding dampers as an energy dissipation system is an acceptable method for controlling damages in structures and improving their seismic performance. In this study, the optimal distribution of dampers for reducing the seismic response of steel frames with multi-degrees freedom is presented utilizing the uniform distribution of deformations. This has been done in a way that, the final configuration of dampers in the frames lead to minimum weight while satisfying the performance criteria. It is shown that such a structure has an optimum seismic performance, in which the maximum structure capacity is used. Then the genetic algorithm which is an evolutionary optimization method is used for optimal arrangement of the steel dampers in the structure. In continuation for specifying the optimal accurate response, the local search algorithm based on the gradient concept has been selected. In this research the introduced optimization methods are used for optimal retrofitting in the moment-resisting frame with inelastic behavior and initial weakness in design. Ultimately the optimal configuration of dampers over the height of building specified and by comparing the results of the uniform deformation method with those of the genetic algorithm, the validity of the uniform deformation method in terms of accuracy, Time Speed Optimization and the simplicity of the theory have been proven.

• Journal of Preventive Medicine and Public Health
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• v.51 no.4
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• pp.181-187
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• 2018

Objectives: To identify factors responsible for potentially clinically unnecessary cervical cancer screenings in women with prior hysterectomy. Methods: A retrospective cross-sectional study was conducted using the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System (BRFSS). This study targeted adult women and examined whether they received a both a Papanicolaou (Pap) test and undergone a hysterectomy in the last three years. We conducted multivariate analyses, including weighted proportions and odds ratios (ORs), based on the modified BRFSS weighting method (raking). The inclusion criteria were adult women (>18 years old) who reported having received a Pap test within the last 3 years. Results: Of all women (n=252 391), 72 366 had received a Pap test, and 32 935 of those women (45%, or 12.5 million, weighted) had a prior hysterectomy. We found that age, race/ethnicity, marital status, family income, health status, time since last routine checkup, and health insurance coverage were all significant predictors. Black, non-Hispanic women were 2.23 times more likely to receive Pap testing after a hysterectomy than white women (OR, 2.23; 95% confidence interval [CI], 1.99 to 2.50). Similarly, the odds for Hispanic women were 2.34 times higher (OR, 2.34; 95% CI, 1.97 to 2.80). The odds were also higher for those who were married (OR, 1.17; 95% CI, 1.08 to 1.27), healthier (OR, 1.24; 95% CI, 1.14 to 1.35), and had health insurance (OR, 1.54; 95% CI, 1.28 to 1.84), after controlling for confounders. Conclusions: We conclude that women may potentially receive Pap tests even if they are not at risk for cervical cancer, and may not be adequately informed about the need for screenings. We recommend strategies to disseminate recommendations and information to patients, their families, and care providers.

• Journal of the Korean Society of School Health
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• v.17 no.1
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• pp.71-83
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• 2004

Purpose: To describe the prevalence, epidemiological characteristics, and related factors of diabetes mellitus in school personnel. Method：5,384 school personnel (2,638 males 2,746 females) received physical examinations at the Seoul School Health Center in 2002. Using the American Diabetes Association criteria, and fasting blood sugar(FBS) was classified as normal at 110>=FBS, borderline 111-125, and the diabetes group 126<=FBS. Related factors of each group were evaluated by gender. Results： In the diabetes group, there were 4.74% males and 0.8% females, and the borderline group was 6.37% males and 2.22% females. The older age group gad a higher distribution in both males and females in the diabetes group. In the diabetes group, the mean and abnormal rate of BMI, systolic hypertension, diastolic hypertension, total cholesterol, GOT, GPT, and GTP were higher than in the normal group. In life style factor, the diabetes group gad a higher distribution of meat eating and smoking more than 20 years than the normal group. The effect of FBS on BMI, BP(blood pressure), total cholesterol, GOT, GPT, and GTP were investigated after controlling for confounding variables. In the borderline and diabetes group, the mean of BMI, BP, total cholesterol, GOT, GPT, and GTP was higher in dose-response effect. In the logistic multiple regression, the related factors of the diabetes group were hypertension and abnormal GTP in males, and abnormal total cholesterol and GTP in females. In the borderline group, the related factors were meat eating, hypertension, and high GOT in males and the older age group, and hypertension, total cholesterol, and abnormal GTP in females. Conclusions: It is possible to manage all related factors of diabetes mellitus except for age. An appropriate program for health promotion is necessary.

• Resources Recycling
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• v.21 no.4
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• pp.76-85
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• 2012

Fluorescent lamps generally involve mercury within their lamp bulbs. Thus if the lamps are disposed as they are, it might cause environmental pollution. On the other hand, as the life of the lamps depends on the degradation of the discharge performance, the fluorescent substance composing the fluorescent substance coating can be recycled by reusing them as the recycled fluorescent substance. Also, the glass material composing the glass bulbs can be reused. The range of search was limited in the open patents of USA (US), European Union (EU), Japan (JP), Korea (KR) and SCI journals from 1977 to 2011. Patents and journals were collected using key-words searching and filtered by filtering criteria. The trends of the patents and journals was analyzed by the years, countries, companies, and technologies. Recovery method of metals from spent fluorescent lamps is mainly the focus on the recovery of precious metals using acid treatment and, detoxification technology is related with controlling process of mercury using a filter system.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.186-190
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• 2000

Objective : The authors experienced that cognitive behavioral therapy(CBT) could replace medication for controlling panic attacks and anticipatory anxiety symptoms. The objective of this study was finding out predicting factors of discontinuation of medication after CBT for patients with panic disorder. Method : A hundred forty-eight patients who met DSM-IV criteria for panic disorder with or without agoraphobia for at least 3 months had completed 12 weekly sessions of Panic Control Therapy(PCT ; Barlow et al). Eighty-one patients who could discontinue medication and sixty-seven patients who could not discontinue medication were measured with several scales as the pre- and post-treatment aassessment. The scales were Beck Depression Inventory(BDI), Clinical Global Impression(CGI), Spielberger State Anxiety Inventory(STAI-state), Anxiety Sensitivity Index(ASI), Body Sensation Questionnaire (BSQ), Panic Belief Questionnaire(PBQ), Agoraphobic Cognition Questionnaire(ACQ), Fear Questionnaire(FQ), Toronto Alexithymia Scale(TAS). Results : At the pre-treatment assessment, the scores of BDI, CGI, STAI-state, ACQ, BSQ were higher in the patients who could discontinue medication than in the patients who could not discontinue medication(t=-2.68, t=-4.88, t=-3.07, t=-3.68, t=-3.35, p<0.01). Conclusion : Patients with panic disorder who were less depressed, less anxious, less agoraphobic and who had less negative cognitions for the bodily sensation and who had higher scores in the therapist's assessment could discontinue their medications.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.4
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• pp.103-116
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• 1994

The objective of this study was to determine the criteria for density and moisture content measurements made with a nuclear density meter on common materials in the construction field. The study also sought to test a full-type nuclear density meter in controlling the density of overlay layers( 2.5~5.0cm). In order to determine the accuracy and reliablility of nuclear guage measurements made on construction materials, laboratory and field tests were conducted. Wooden blocks( 65 x 45 ${\times}$ 50 cm) and a special steel compactor( 4.7kg) were constructed in order to carry out tests which were conducted on three different materials; coarse gramed soil, fine grained soil, and AC material. Throughout all laboratory and field tests, the nuclear density and moisture content were determined using Humboldt 5OOLP nuclear gauge. The tests on subgrade material entailed obtaining density measurements by means of both the sand replacement method and the nuclear density meter. The results of the sand replacement method were then compared to the readings recorded bu the meter. As in the subgrade material tests, density measurements made during AC pavement tests were also determined using the unclear meter in addition to a second means; through the core method. The meter readings and core densties were compared as was done in the tests on subgrade materials. The correlation between the results of the sand replacement test( also, the core method) and meter readings on subgrade material was then determined. Sirnilarly, the observed results were then analyzed through linear regression. The tests to determine thin-lift density by means of a full-type nuclear density meter also conducted on the overlay layers( about 4. 8cm thickness) above AC pavements at road construction sities in Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.1
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• pp.49-60
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• 2000

The concentration of atmospheric mercury(Hg0 and relevent environmental parameters that include both meteorological and criteria pollutant data were dtermined at hourly intervals during two field campaigns covering the periods of September 1997 and May/June 1998. The mean concentrations of Hg for the two study periods were computed as 3.94 and 3.43ngm-3, respectively. Through a separation of these data into both daytime and nighttime periods, we further analyzed diurnal variation patterns for Hg between two different seasons. Using our Hg data sets, we were able to recognize two contrasting diurnal variation patterns of Hg between two diffeerent seasons that can be characterized as: (1) the occurrences of peak Hg concentration during daytime(fall0 and (2) slight reductions in daytime Hg concentration relative to nighttiime Hg data(summer). To study the systematic differences in diurnal patterns between two different seasons, we analyzed Hg data in terms of different statistical approaches such as correlation(and linear regression0 and factor analysis. Results of these analyses consistently indicated that different mechanisms were responsible for controlling the daytime distribution patterns of Hg. The variation of boundary layer conditions betwen day/night periods may have been important in introducing the relative reduction in daytime Hg levels during summer. However, when the relationship between Hg and concurrently determined O3 is concerned, these differences are unlikely to be an effective sink mechanism within the ranges of ozone concentrations determined concurrently during this study, regardless of season. To further provide the general account for short-term variations in Hg distribution data, we should be able to describe the various factors underlying its sink mechanism.

• Proceedings of the Technology Innovation Conference
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• 2002.06a
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• pp.203-223
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• 2002

In Korea, Public Research Institutes(PRIs) are today faced with the challenges of creating values by transferring technologies in store within themselves to private commercial sector. Recently, It has been increasingly pointed out that PRIs have the poor capability to valuate prospective technologies of their own, and don't run the reasonable technology transfer mechanism in terms of establishing royalty rate and initial payment, designing remuneration to inventor, screening qualified licensee, and controlling the moral hazard. This paper develops an enhanced mathematical model of technology transfer from a PRI to a private industrial firm with including the inventor as an important player. The model is made up of the main part which derives the optimal royalty rate by maximizing the social welfare and sharing risk fairly between players and some sub-parts. The one sub-part is a principal-agent model which makes it possible to control the moral hazard of inventors, and the other part provides the criteria for screening appropriate licensees. Moreover, the moral hazard between inventor and licensee is addressed by introducing the cost reduction function of efforts exerted by them. The model is able to relate the optimal royalty rate to the parameters that represent the environments under which the concerned parties operate. Especially, the ratio of initial payment over the value of transferred technology is calculated from the binding relation with the royalty rate. The paper shows that the model suggested here is more enhanced by comparing with the existing technology transfer mechanism. Finally, the paper allows us to find better strategies for effective technology transfer and further develop more sophisticated technology transfer model.