• Title/Summary/Keyword: convergence rate

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In-vitro Neuroprotective Effect of Aricumin(Turmeric extract) (아리큐민의 In-vitro 신경보호 효과)

  • Yoon, Nam kyu;Kim, Byung Kwon;Ryu, Hyeon yeol;Seo, Bo Seung;Shin, Chang Ho;Kim, Kwan Kyu;Lee, Han Joo
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.3
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    • pp.291-296
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    • 2022
  • This study was conducted on curcumin which had increased bioavailability as a potential AChE inhibitor for the treatment of neurodegenerative diseases. The purpose of this study is to confirm the in vitro neuroprotective effect on Aricumin (turmeric extract). To confirm the neuroprotective effect, AChE inhibition for Aricumin was evaluated, and cell viability was analyzed for HT-22cell, and oxidative stress (glutamate, H2O2)-induced HT-22 cytotoxicity was evaluated. As a result of the change in the AChE inhibition rate of Aricumin (Turmeric extract), it was confirmed that Aricumin at a concentration of 39.06㎍/ml or higher inhibited AChE activity by about 20% and more. And it was confirmed that the cytotoxicity of HT-22 cells induced by oxidative stress (Gluamate 5 mM and H2O2 500 µM) was significantly inhibited from 0.01 to 0.1 mg/ml concentration (p<005). These results suggest that Aricumin (turmeric extract) have potential neuroprotective effects.

Stress Intensity Factor of Cracked Plates with Bonded Composite Patch by p-Convergence Based Laminated Plate Theory (p-수렴 적층 평판이론에 의한 균열판의 팻취보강후 응력확대계수 산정)

  • Woo, Kwang-Sung;Han, Sang-Hyun;Yang, Seung-Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.5A
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    • pp.649-656
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    • 2008
  • The enhancement of the service life of damaged or cracked structures is a major issue for researchers and engineers. The hierarchic void element based on the integrals of Legendre polynomials is used to characterize the fracture behaviour of unpatched crack as well as repaired crack with bonded composite patches by computing the stress intensity factors and stress contours at the crack tip. Since the equivalent single layer approach is adopted in this study, the proposed element is necessary to represent a discontinuous crack part as a continuum body with zero stiffness. Thus the aspect ratio of this element to represent the crack should be extremely slender. The sensitivity of numerical solution with respect to energy release rate, displacement and stress has been tested to show the robustness of zero stiffness element as the aspect ratio is increased up to 2000. The stiffness derivative method and displacement extrapolation method have been applied to calculate the stress intensity factors of Mode I problem. It is noted that the proposed hierarchical void element can be one of alternatives to analyze the patched crack problems.

Relationship between Grain Size and Organic Carbon Content of Surface Sediments in the Major Estuarine Areas of Korea (국내 주요 하구역 표층퇴적물의 입도와 유기탄소 함량 관계)

  • BOO-KEUN KHIM;JU-YEON YANG;HYUK CHOI;KWANGKYU PARK;KYUNG HOON SHIN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.28 no.4
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    • pp.158-177
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    • 2023
  • An estuary is a transitional water area that links the land and sea through rivers and streams, transporting various components from the land to the sea, which plays an important role in determining primary productivity in the coastal environment, and this coastal ecosystem captures a huge amount of carbon into biomass, known as blue carbon, which mitigates climate change as a potential carbon reservoir. This study examined the variation of mean grain size and organic carbon content of the surface sediments for 6 years and analyzed their relationship in the western and southern estuarine areas (Han River Estuary, Geum River Estuary, Yeongsan River Estuary, Seomjin River Estuary, and Nakdong River Estuary) and the East Sea upwelling area. During the sampling period (2015 to 2020), seasonal variation of both properties was not observed, because their variations might be controlled by diverse oceanographic environments and hydrographic conditions within each survey area. However, despite the synoptic problem of all samples, the positive relationship was obtained between the averages of mean grain size and organic carbon content, which clearly distinguishes each survey area. The unique positive relationship in all estuarine areas implies that the same process by sediment clay particles is important in the organic carbon accumulation. However, additional important factor may be expected in the organic carbon accumulation in the East Sea upwelling area. Further necessary data (sedimentation rate, dry bulk density etc) should be required for the estimation of carbon stock to evaluate the major estuaries in Korea as potential carbon reservoirs in the coastal environment.

Study on the Experience of Unbelief in the Process of Providing Home Visiting Care Service: Focusing on the perspective of the Facility Director (재가방문요양 서비스 제공과정에서 겪는 불신경험에 관한 연구: 시설운영자 관점을 중심으로)

  • Jun-Suk Kim;Ji-Hye Kim;Jung-Mi Kim;Mi-Young Park;Byung Woo Lim
    • Journal of Industrial Convergence
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    • v.21 no.10
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    • pp.65-80
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    • 2023
  • Through inductive content analysis, this study sought to examine the crisis experienced by the institution, the quality of service, and the distrust of the system and institution based on the experience of distrust in the home-visiting care service of bbeneficiary and guardians. FGI was conducted on five managers of institutions that provide home-visiting care services. As a result, the central phenomenon was found: deterioration of service quality, distrust of systems and institutions, and difficulties in opera-ting long-term care institutions. In order to improve the quality of home-visited care services and build trust in care workers and institutions, first, home-based associations or operating corporations should develop new education program plans and manuals to strengthen the capabilities of care workers and social workers. Second, the NHIS's monitoring system and the professional management system of care workers should be established. Third, it is necessary to improve awareness of the role, expertise, and rights of care workers, and fourth, improvement measures are required to reduce the turnover rate of care workers, which is the cause of the deterioration of the quality of long-term care services.

Adverse Effects on EEGs and Bio-Signals Coupling on Improving Machine Learning-Based Classification Performances

  • SuJin Bak
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.10
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    • pp.133-153
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    • 2023
  • In this paper, we propose a novel approach to investigating brain-signal measurement technology using Electroencephalography (EEG). Traditionally, researchers have combined EEG signals with bio-signals (BSs) to enhance the classification performance of emotional states. Our objective was to explore the synergistic effects of coupling EEG and BSs, and determine whether the combination of EEG+BS improves the classification accuracy of emotional states compared to using EEG alone or combining EEG with pseudo-random signals (PS) generated arbitrarily by random generators. Employing four feature extraction methods, we examined four combinations: EEG alone, EG+BS, EEG+BS+PS, and EEG+PS, utilizing data from two widely-used open datasets. Emotional states (task versus rest states) were classified using Support Vector Machine (SVM) and Long Short-Term Memory (LSTM) classifiers. Our results revealed that when using the highest accuracy SVM-FFT, the average error rates of EEG+BS were 4.7% and 6.5% higher than those of EEG+PS and EEG alone, respectively. We also conducted a thorough analysis of EEG+BS by combining numerous PSs. The error rate of EEG+BS+PS displayed a V-shaped curve, initially decreasing due to the deep double descent phenomenon, followed by an increase attributed to the curse of dimensionality. Consequently, our findings suggest that the combination of EEG+BS may not always yield promising classification performance.

Work-Life Balance Policies in Germany and the Participation of Private Companies (독일의 일·가정 양립정책과 민간 기업의 참여)

  • Nam, Hyun-Joo
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.729-736
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    • 2023
  • Traditionally, Germany, a conservative welfare state, has pursued a male breadwinner model based on gender division of labor. For a long time, Germany tried to address low fertility through economic support centered on cash benefits, but it was not successful. In 2007, the German government began to shift the paradigm of family policy for work-life balance under the slogan of "A mix of time policy, income transfer, and infrastructure." When the issue of low birth rates emerged as a national concern in Germany, there was a growing social sentiment that not only the government but also private companies should contribute to increasing fertility by providing family-friendly personnel policies and working conditions. Private companies have been voluntarily improving family-friendly working conditions beyond legal obligations, aiming to secure personnel and prevent turnover. Germany's fertility rate is currently rising toward the European average level in 2023, which can be attributed to the government's work-life balance policies and the participation of private companies. In terms of improving work-life balance policies in Korea, it has been proposed to change the perception of the need for fathers to participate in child care, to make parental leave compulsory for men, to guarantee employment for women after childbirth, to expand child care facilities, and to revitalize family-friendly policies in companies.

The Effect of Korean-Japanese College Students' Perception of Welfare, Dementia Perception, and Dementia Attitude on Dementia Policy Perception (한·일 대학생의 노인복지 인식, 치매 인식, 치매태도가 치매정책 인식에 미치는 영향)

  • Ae-Ran Ryu;Kuk-Gwen Lee
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.349-355
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    • 2023
  • This study attempted to examine the effect of Korean and Japanese college students' perception of welfare for the elderly, dementia perception, and dementia attitude on dementia policy. The main results are as follows. As a result of analyzing the impact of Korean-Japanese college students on their perception and attitude of dementia policy, it was found that Korean-Japanese college students' perception of welfare for the elderly and dementia attitude had a positive (+) effect on dementia policy perception. As a result, I would like to present the following implications. Korea and Japan have developed social insurance systems for the elderly in a low birth rate and aging society, and are developing and implementing support services suitable for the culture of both countries. In the perception of dementia policies of college students in Korea and Japan, the influence of long-term care insurance for the elderly in Korea and nursing care insurance in Japan has led to changes in the perception of dementia among college students. However, it has been shown that dementia awareness does not affect dementia policy awareness, indicating that college students lack dementia awareness. Dementia awareness can increase the demand for the development of various dementia-related services or dementia policies, but low dementia awareness can lead to misunderstanding or negative perceptions of dementia. This can also affect the perception of dementia policies, and services and policies such as social support, prevention, and treatment related to dementia may not be sufficiently developed. In order to compensate for these problems in the future, efforts should be made to improve awareness through the provision of various information such as the government and society to help improve and understand dementia awareness for college students.

Optimal Pricing and Ordering Policies for an Exponential Deteriorating Product under Order-size-dependent Delay in Payments (주문량에 따라 종속적인 신용거래 하에 퇴화성제품의 최적 가격 및 재고정책)

  • Seong-Whan Shinn
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.493-499
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    • 2023
  • Trade credit refers to a transaction where a product supplier allows an distributor to defer payment for a certain period of time for the purchase cost of the products. This practice is generally permitted as a means of differentiation between competing companies. Such trade credit is commonly granted based on the volume of transactions, aiming to increase customer orders. From the perspective of the distributor, trade credit allows for a deferred payment period for the purchase cost, leading to cost savings in inventory investment. These cost savings in inventory investment can be a factor in reducing selling prices with the aim of increasing customer demand. In this study, we analyze a model that determines the optimal selling price and order quantity from the perspective of the distributor, assuming that the supplier allows a deferred payment period dependent on the transaction volume. We assume that the final customer's annual demand exhibits an exponential decrease with respect to the distributor's selling price, using a constant price elasticity function. To analyze the problem, we assume that the product deteriorates at a constant rate over time and aim to establish an inventory model for the intermediate distributor. We also want to analyze the impact of deterioration on the inventory policies of the intermediate distributor.

Comparative Analysis of Low Fertility Response Policies (Focusing on Unstructured Data on Parental Leave and Child Allowance) (저출산 대응 정책 비교분석 (육아휴직과 아동수당의 비정형 데이터 중심으로))

  • Eun-Young Keum;Do-Hee Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.769-778
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    • 2023
  • This study compared and analyzed parental leave and child allowance, two major policies among solutions to the current serious low fertility rate problem, using unstructured data, and sought future directions and implications for related response policies based on this. The collection keywords were "low fertility + parental leave" and "low fertility + child allowance", and data analysis was conducted in the following order: text frequency analysis, centrality analysis, network visualization, and CONCOR analysis. As a result of the analysis, first, parental leave was found to be a realistic and practical policy in response to low fertility rates, as data analysis showed more diverse and systematic discussions than child allowance. Second, in terms of child allowance, data analysis showed that there was a high level of information and interest in the cash grant benefit system, including child allowance, but there were no other unique features or active discussions. As a future improvement plan, both policies need to utilize the existing system. First, parental leave requires improvement in the working environment and blind spots in order to expand the system, and second, child allowance requires a change in the form of payment that deviates from the uniform and biased system. should be sought, and it was proposed to expand the target age.

Factors Influencing Depressive Symptoms Among Middle-aged Women: A Comparison of Walking and Nonwalking (중년여성의 우울증상 영향요인: 걷기와 비걷기 비교)

  • Ju-Young Park;Mi-Ah Shin
    • Journal of Industrial Convergence
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    • v.21 no.12
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    • pp.63-73
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    • 2023
  • This study aimed to investigate factors influencing depressive symptoms among middle-aged women based on walking and nonwalking. The participants of the study were 56,007 women aged 40-64 years. A complex sample statistical analysis was conducted. Notably, 48.9% of middle-aged women were in the walking group and 51.1% were in the nonwalking. In the nonwalking group, relative to the walking group, more people had high school diploma as their highest level of education, and were 40-49 years old, unemployed, and public assistance recipients than in the walking group. In addition, in the nonwalking group, more people had sleeping durations of less than 7 hours, perceived stress, and depressive symptoms than in the walking group. Factors influencing depressive symptoms were identified as less than 7 hours of sleeping duration and high perceived stress in both the walking and nonwalking groups, and the degree of influence was higher in the walking group than in the non-walking group, suggesting than further studies are needed to identify the cause. The results confirmed that perceived stress and depressive symptoms in middle-aged women could be reduced by walking. Therefore, if middle-aged women continue to engage in walking practices appropriate for them, it will enhance their walking rate, reduce stress, and improve their depressive symptoms.