• Earthquakes and Structures
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• v.10 no.1
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• pp.141-161
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• 2016

In seismic fragility and risk analysis, the definition of structural limit state (LS) capacities is of crucial importance. Traditionally, LS capacities are defined according to design code provisions or using deterministic pushover analysis without considering the inherent randomness of structural parameters. To assess the effects of structural randomness on LS capacities, ten structural parameters that include material strengths and gravity loads are considered as random variables, and a probabilistic pushover method based on a correlation-controlled Latin hypercube sampling technique is used to estimate the uncertainties in LS capacities for four typical reinforced concrete frame buildings. A series of ten LSs are identified from the pushover curves based on the design-code-given thresholds and the available damage-controlled criteria. The obtained LS capacities are further represented by a lognormal model with the median $m_C$ and the dispersion ${\beta}_C$. The results show that structural uncertainties have limited influence on $m_C$ for the LSs other than that near collapse. The commonly used assumption of ${\beta}_C$ between 0.25 and 0.30 overestimates the uncertainties in LS capacities for each individual building, but they are suitable for a building group with moderate damages. A low uncertainty as ${\beta}_C=0.1{\sim}0.15$ is adequate for the LSs associated with slight damages of structures, while a large uncertainty as ${\beta}_C=0.40{\sim}0.45$ is suggested for the LSs near collapse.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.345-358
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• 2019

The purpose of this study is to develop the Internet vulnerability index of adolescents. To do this, we used the original data of long - term follow - up survey for the internet overdependency cause analysis conducted by NIA in 2018, and analyzed the correlation between alternatives of internet vulnerability index and personal psychology by using linear regression analysis. Factor analysis showed that the relationship with the surroundings was indexed by adding 9 items to positive factors such as family acceptance, peer attachment, and teacher favorability. The relationship between the surroundings and self - stigmatization is confirmed, and the relationship between the surroundings and the Internet fragility is predicted to be negatively related, and the digital capacity is also assumed to be negatively correlated with the Internet vulnerability. In order to develop the specific form of the Internet vulnerability index, personal psychology and linear regression analysis were conducted. As a result, positive factors and R value of personal psychology were increased when considering the relationship with the environment and the digital capacity rather than the Internet overdependency model. Based on these implications, we discussed the implications and limitations of this study.

• Korean Journal of Acupuncture
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• v.36 no.2
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• pp.115-126
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• 2019

Objectives : Osteoporosis is a condition characterized by low bone mass and increased bone fragility. It has become a major problem of senior citizens. The purpose of this study is to experiment the effect of water extract of Forsythiae Fructus (wFF) on osteoclast differentiation; and the other purpose is to examine the effect of wFF on osteoporosis in ovariectomized rat. Methods : To investigate the effect of wFF on osteoclast differentiation and activity, RAW 264.7 cells were used. The number of TRAP positive cell, TRAP activity, pit area, mRNA expression of makers (RANK, TRAP, CA II, CTK, MMP-9, NFATc1, c-Fos), protein expression of makers (NFATc1, c-Fos) were investigated. For in vivo study, 40 female Sprague-Dawley (SD) rats were induced osteoporosis by ovariectomy (OVX) and then tested for anti-osteoporosis effect by administration of wFF. Results : wFF suppressed osteoclatogenesis, TRAP activity and pit area formation. Moreover, wFF decreased the expression of master differentiation factors (NFATc1, c-Fos) and also reduced the osteoclastogenesis-related markers (TRAP, CA II, CTK, MMP-9). These suggest that wFF inhibit osteoclasts differentiation and bone resorption. In the OVX rat model, wFF inhibited decreasing of BMD and trabecular area. Conclusions : Forsythiae Fructus should be effective for osteoporosis prevention and treatment.

• Structural Engineering and Mechanics
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• v.83 no.3
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• pp.327-340
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• 2022

The Collapse Margin Ratio (CMR) is a notable index used for seismic assessment of the structures. As proposed by FEMA P695, a set of analyses including the Nonlinear Static Analysis (NSA), Incremental Dynamic Analysis (IDA), together with Fragility Analysis, which are typically time-taking and computationally unaffordable, need to be conducted, so that the CMR could be obtained. To address this issue and to achieve a quick and efficient method to estimate the CMR, the Artificial Neural Network (ANN), Response Surface Method (RSM), and Adaptive Neuro-Fuzzy Inference System (ANFIS) will be introduced in the current research. Accordingly, using the NSA results, an attempt was made to find a fast and efficient approach to derive the CMR. To this end, 5016 IDA analyses based on FEMA P695 methodology on 114 various Reinforced Concrete (RC) frames with 1 to 12 stories have been carried out. In this respect, five parameters have been used as the independent and desired inputs of the systems. On the other hand, the CMR is regarded as the output of the systems. Accordingly, a double hidden layer neural network with Levenberg-Marquardt training and learning algorithm was taken into account. Moreover, in the RSM approach, the quadratic system incorporating 20 parameters was implemented. Correspondingly, the Analysis of Variance (ANOVA) has been employed to discuss the results taken from the developed model. Additionally, the essential parameters and interactions are extracted, and input parameters are sorted according to their importance. Moreover, the ANFIS using Takagi-Sugeno fuzzy system was employed. Finally, all methods were compared, and the effective parameters and associated relationships were extracted. In contrast to the other approaches, the ANFIS provided the best efficiency and high accuracy with the minimum desired errors. Comparatively, it was obtained that the ANN method is more effective than the RSM and has a higher regression coefficient and lower statistical errors.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.67-76
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• 2022

COVID-19 struck labor markets around the world, exposing and exacerbating the gender inequalities within the human capital structure. The last, in its turn, jeopardizes the return of the national economies to the growth trajectory undermined by pandemic impact. The authors assume that COVID-19 disproportionately affected the employment rates of women and men, which led to increased gender inequality in the labor market, which, in turn, affected GDP growth rates in the EU. To prove this hypothesis two research questions are discovered: 1) whether there was a different correlation between the number of COVID-19 cases in the EU and indicators of the labor market for women and men; and 2) whether there was a link between the growth of gender inequality in the EU labor market and the GDP dynamics in these countries. The analysis of the correlation between the number of cases of COVID-19 and indicators of the labor market in the EU revealed faster growth of women's unemployment rates compared to men's ones as the COVID-19 incidence unfolded. Multiple linear regression and factor analysis have been used to investigate the influence of gender inequality in the labor market on GDP dynamics. Despite the methodological limitations, the proposed model is both a sound argument and an analytical basis in favor of gender-responsive economic recovery backed by the systematic and consistent gender equality policy of a government.

• Journal of Korean Neurosurgical Society
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• v.63 no.4
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• pp.433-443
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• 2020

Objective : Osteoporosis is a disease of unbalanced bone metabolism that results in low bone mineral density with increased bone fragility and propensity for fractures. The increased rate of bone fracture due to osteoporosis places a significant burden on public health care expenditures. Therefore, numerous studies have been designed and performed to identify the drugs or health foods that can improve the bone quality or quantity. This study was designed to evaluate and analyze the therapeutic effects of rutin on histomorphometric values of the spine and femur in an osteoporotic mouse model induced by bilateral ovariectomy. Methods : Thirty female ICR mice (8 weeks old) underwent either a sham operation (only abdominal incision, sham group, n=10) or bilateral ovariectomy (n=20). The ovariectomized (OVX) animals were randomly divided into two groups : untreated OVX group (OVX-C, n=10), or rutin-administered group (OVX-R, n=10). The OVX-C group received weight-adjusted doses of saline vehicle and the OVX-R group received 50 mg/kg of rutin intraperitoneally, starting 1 day after surgery. At 4 and 8 weeks after surgery, serum estrogen, osteocalcin, alkaline phosphatase (ALP), and the telopeptide fragment of type I collagen C-terminus (CTX-1) were analyzed. Interleukin (IL)-1β, IL-6, IL-10, and tumor necrosis factor (TNF)-α were also analyzed. Bone histomorphometric parameters of the 4th lumbar vertebra and femur were determined by micro-computed tomography. Results : In OVX-C group, ALP, osteocalcin, CTX-1, IL-1β, IL-6, and TNF-α levels were significantly increased at 4 and 8 weeks compared to sham operation group. Rutin administration after OVX statistically significantly reduced ALP, CTX-1, IL-1β, IL-6, and TNF-α levels at 4 and 8 weeks. Rutin administration also improves bone histomorphometric parameters including trabecular bone volume fraction, trabecular thickness, and trabecular number. Trabecular separation was also decreased in OVX-R group compared to OVX-C group. Conclusion : The present study demonstrated that rutin has therapeutic effects on improving bone histomorphometric values in an OVX mouse model. The improvement in histomorphometric values may be associated with the reduction of osteoclastic activity via inhibition of IL-1β, IL-6, and TNF-α. In future studies, the mechanism for the effect of rutin on osteoporosis should be demonstrated more clearly to use rutin in human osteoporosis.

• Journal of Intelligence and Information Systems
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• v.23 no.4
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• pp.57-76
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• 2017

Recently, consumer needs are diversifying as information technologies are evolving rapidly. A lot of IT devices such as smart phones and tablet PCs are launching following the trend of information technology. While IT devices focused on the technical advance and improvement a few years ago, the situation is changed now. There is no difference in functional aspects, so companies are trying to differentiate IT devices in terms of appearance design. Consumers also consider design as being a more important factor in the decision-making of smart phones. Smart phones have become a fashion items, revealing consumers' own characteristics and personality. As the design and appearance of the smartphone become important things, it is necessary to examine consumer values from the design and appearance of IT devices. Furthermore, it is crucial to clarify the mechanisms of consumers' design evaluation and develop the design evaluation model based on the mechanism. Since the influence of design gets continuously strong, various and many studies related to design were carried out. These studies can classify three main streams. The first stream focuses on the role of design from the perspective of marketing and communication. The second one is the studies to find out an effective and appealing design from the perspective of industrial design. The last one is to examine the consumer values created by a product design, which means consumers' perception or feeling when they look and feel it. These numerous studies somewhat have dealt with consumer values, but they do not include product attributes, or do not cover the whole process and mechanism from product attributes to consumer values. In this study, we try to develop the holistic design evaluation model based on consumer values based on three-step approach from product attributes, perceived attributes, to consumer values. Product attributes means the real and physical characteristics each smart phone has. They consist of bezel, length, width, thickness, weight and curvature. Perceived attributes are derived from consumers' perception on product attributes. We consider perceived size of device, perceived size of display, perceived thickness, perceived weight, perceived bezel (top - bottom / left - right side), perceived curvature of edge, perceived curvature of back side, gap of each part, perceived gloss and perceived screen ratio. They are factorized into six clusters named as 'Size,' 'Slimness,' 'No-Frame,' 'Roundness,' 'Screen Ratio,' and 'Looseness.' We conducted qualitative research to find out consumer values, which are categorized into two: look and feel values. We identified the values named as 'Silhouette,' 'Neatness,' 'Attractiveness,' 'Polishing,' 'Innovativeness,' 'Professionalism,' 'Intellectualness,' 'Individuality,' and 'Distinctiveness' in terms of look values. Also, we identifies 'Stability,' 'Comfortableness,' 'Grip,' 'Solidity,' 'Non-fragility,' and 'Smoothness' in terms of feel values. They are factorized into five key values: 'Sleek Value,' 'Professional Value,' 'Unique Value,' 'Comfortable Value,' and 'Solid Value.' Finally, we developed the holistic design evaluation model by analyzing each relationship from product attributes, perceived attributes, to consumer values. This study has several theoretical and practical contributions. First, we found consumer values in terms of design evaluation and implicit chain relationship from the objective and physical characteristics to the subjective and mental evaluation. That is, the model explains the mechanism of design evaluation in consumer minds. Second, we suggest a general design evaluation process from product attributes, perceived attributes to consumer values. It is an adaptable methodology not only smart phone but also other IT products. Practically, this model can support the decision-making when companies initiative new product development. It can help product designers focus on their capacities with limited resources. Moreover, if its model combined with machine learning collecting consumers' purchasing data, most preferred values, sales data, etc., it will be able to evolve intelligent design decision support system.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.12
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• pp.89-98
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• 2015

This paper provides a robust and non-fragile $H_{\infty}$ controller design algorithm for time-delayed systems with randomly occurring polytopic uncertainties and disturbances. First, we design time-delayed system considering randomly occurring uncertainties and disturbances. Next, The sufficient condition for the existence of robust and non-fragile $H_{\infty}$ controller is presented by LMI(linear matrix inequality) using Lyapunov stability analysis and $H_{\infty}$ performance measure. Since the obtained condition can be expressed as a PLMI(parameterized linear matrix inequality) by changes of variables and Schur complement, all solutions including controller gain, degrees of controller satisfying non-fragility, $H_{\infty}$ norm bound ${\gamma}$ can be calculated simultaneously. Finally, numerical examples are given to illustrate the performance and the effectiveness of the proposed robust and non-fragile $H_{\infty}$ controller compared with the deterministic uncertainty model even though there exists randomly occurring uncertainties, disturbances and time delays.

• Journal of the Korean Society for Library and Information Science
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• v.20
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• pp.65-125
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• 1991

The study has tried to analize and appraise how did public library system under the Japanese imperialism affect the establishment and managemant of Korean public libraries. To achieve the purpose of the above-mentioned study, the contents of $\ulcorner$Japanese library statute$\lrcorner$ under Japanese imperialism and the current $\ulcorner$Korean library law$\lrcorner$ have been mutually compared, at the same time, the vestiage of Japanese imperialism in view of the establishment, personnel administration and reading systems have been concretely investigated, analyzed and compared. The conclusions obtained from the above are as followings. 1. In those days of the Korean Liberation, the situation of Korean public libraries was such as it under the Japanese rule and so, their names were only changed. However, as a part of its independent activities, the national library have once carried out the various programs such as the training of professional librarians, the establishment of the new classification schedule and the chief Librarian and deputy Librarian from the professional librarians in the office regulations, and they were well worth being the good examples for today's Korean library circle. Though the Goverment of the Republic of Korea had been formally established, the situation of the library circle was very dull owing to the Korean war for a long time. In 1963, $\ulcorner$The Korean library law$\lrcorner$ was promulgated, but the establishment of public libraries did not give satisfactory results because of the institutional fragility. In the 1980's the importance of library was embossed from the viewpoint of life-long education and the number of libraries was increased. However, there were still the remaining vestiges of Japanese library system in the practical library services. 2. After the Korean Liberation, the influnces of public library system under the Japanese imperialism showed in the office regulation of national library and the Korea library Law were also in the legal mechanism. In particular, the regulations of $\ulcorner$The staff-member of public library$\lrcorner$ and $\ulcorner$Admission fee of public library$\lrcorner$ including the chief librarian have referred to the library system under the Japanese imperialism since the liberation day to date. 3. At that time of the Korean Liberation, the U.S.Military Government Office had decided that the public library administration should be attached to the administration of local and internal affairs in accordance with the Japanese administative system. As a result, the public libraries had been forced to be indirectly affected by public library system under the Japanese imperialism for twenty years since the Liberation. 4. Since the Liberation, the personnel adminstration of public library has been so far on the steps of model under the Japanese imperialism. As the result of the field survey, the position standards of local chief librarians, non-professional character, the extra post system and the preponderant appointment of non-professional offices have analyzed by the influence of Public library system under the Japanese imperialism. Therefore, the Government authorities-concerned must readjust the standards of qualification and the divided duties corresponding to the position of public library staff members and to stipulate expressly in the revised library law. In addition, the regulation of the admission fee should be also actively detected for the free adminssion of library users. 5. Since the Liberation Day, the reading methods of public library have been so far similar to reading method under the Japaness imperialism. For example, the admission fee levied, the complicated procedures of using books including entrance and exit of a library, no-admission system, the limited lending books, the deposit system of outdoor lending books and the surety liable jointly and severally are originally caused by bureaucracy of under the Japanese imperialism. Therefore, the public libraries should make an offer space and opportunities which can enjoy freedom to the gull in future. The procedures and standards of library users will be simplified, if possible. As the above-mentioned, the actual conditions of Korean public libraries have been examined and analyzed. As the result of it, there are still the remaining vestiges of public library system under the Japanese imperialism in the establishment and management of the nation-wide public libraries. Such the remnants are an obstacle to the democratic development of public libraries and so, the authorities-concerned should take the proper-measures as soon as possible.