• 한국전산구조공학회논문집
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• 제24권4호
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• pp.413-419
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• 2011

나노 크기의 허니콤 구조물은 거시적 크기의 허니콤 구조물에 비해 보다 높은 부피 대비 표면적 비율을 구현하여 전기적, 화학적인 촉매로써 기능성을 극대화할 수 있다. 나노 크기의 구조물은 거시적 크기의 구조물과 다른 기계적 거동양상을 보이며 이는 표면효과에 기인한다. 이러한 표면효과는 원자 수준 전산모사(atomistic simulation)를 통해 규명할 수 있으나 나노 허니콤 구조물의 거동을 예측하는 것은 현실적으로 과도한 전산자원 및 계산시간으로 인해 불가능한 실정이다. 본 연구에서는 표면응력 탄성모델을 적용한 브리징방법을 균질화기법과 연계하여 나노 크기의 허니콤 구조물의 기계적 거동을 효율적으로 예측하였다.

• Structural Engineering and Mechanics
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• 제14권1호
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• pp.21-38
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• 2002

A control algorithm combining viscous and non-linear Reid damping mechanisms has been recently proposed by the authors to command active friction dampers. In this paper, friction dampers and the proposed algorithm are applied to control the seismic responses of a nonlinear 20-story building. Piezoelectric stack actuators are used to implement the control algorithm. The capacity of each damper is determined by the practical size of piezoelectric actuators and the availability of power supply. The saturation effect of the actuators on the building responses is investigated. To minimize the peak story drift ratio or floor acceleration of the building structure, a practical sequential procedure is developed to sub-optimally place the dampers on various floors. The effectiveness of active friction dampers and the efficiency of the proposed sequential procedure are verified by subjecting the building structure to four earthquakes of various intensities. The performance of 80 dampers and 137 dampers installed on the structure is evaluated according to 5 criteria. Numerical simulations indicated that the proposed control algorithm effectively reduces the seismic responses of the uncontrolled 20-story building, such as inelastic deformation. The sub-optimal placement of dampers based on peak acceleration outperforms that based on peak drift ratio for structures subjected to near-fault ground motions. Saturation of piezoelectric actuators has adverse effect on floor acceleration.

• 대한안전경영과학회지
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• 제14권4호
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• pp.313-319
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• 2012

SW industry is important at entire industry in Korea and also one of new growth engine industry. This paper deals with the economic effect of SW industry through input-output analysis. We reconstruct the SW industry by extracting and combining SW portion from other industries of the inter-industry relation table. We obtain that production inducement coefficients, value added inducement coefficients, employment inducement coefficients, and job position inducement coefficients are higher than average inducement coefficients of all industries.

• Geomechanics and Engineering
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• 제17권6호
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• pp.543-551
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• 2019

In China, serious environmental problems are induced by the extremely soft construction waste slurries in many urban areas, and there is no appropriate method to treat it presently. In this paper, four model tests were conducted to investigate the efficiency of waste slurry treatment by combining three conditioning agents which can change characteristics of the slurries with a traditional vacuum preloading method. The tests of size analysis of particle aggregate were conducted to investigate the influence of different conditioning agents on the size distributions of particle aggregate. During the model test, the discharged water volumes were monitored. The pore-size distribution and void ratio of the waste slurries after the vacuum preloading were measured by mercury intrusion porosimetry (MIP). It is found that 1) During the natural precipitation, volume of water out of the organic agent is higher than that of the mixed agent, but it is smaller than that of the mixed agent in the vacuum preloading stage; 2) the mixed agent has a higher total volume of water out than the organic agent and the inorganic agent after test, while the organic agent and the inorganic agent have little difference with respect to the drainage effect. The results demonstrate that the combination of mixed conditioning agent and vacuum preloading for the solid-liquid separation in waste slurry has a satisfactory effect and can be applied in engineering practice.

• 인터넷정보학회논문지
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• 제20권1호
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• pp.113-124
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• 2019

Recently, Omni Channel Services has been considered the most innovative business strategy. Omni-Channel sees a variety of channels from all channels viewpoints, organically combining each channel to provide a seamless experience for consumers. In other words, Omni-Channel is not simply a systematic integration of channels, but a means of delivering consistent services to consumers in all processes through a strategy to an organic connection. The aim of this study is to provide a comprehensive insight into the decision factors affecting the adoption of Omni-channel. For this purpose, an empirical analysis is conducted on the course of acceptanceof the Omni-channel service based on the Unified Theory of Acceptance and Use of Technology (UTAUT) and Task-technology fit (TTF), an effective model frequently selected to describe the acceptance of service in the introduction phase of new information technology. As a result of the study, it was confirmed that the task characteristics and the technical characteristics had a positive effect on the task-technology fit, and the task-technology fit had a positive effect on the performance expectancy. In addition, task-technology fit, performance expectancy, and social influence have a positive effect on the intention to use the Omni-Channel. This study is intended to deliver an experimental meaning by proposing a strategical measure to understand the behaviorsand uses of consumers in the Omni-channel service environment and increase the customer satisfaction for the system.

• Journal of Preventive Medicine and Public Health
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• 제54권2호
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• pp.110-118
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• 2021

Objectives: A growing number of people depend on flexible employment, characterized by outsider employment status and perceived job insecurity. This study investigated whether there was a synergistic effect of employment status (full-time vs. part-time) and perceived job insecurity on major depressive disorder. Methods: Data were derived from the 2012 Canadian Community Health Survey-Mental Health of 12 640 of Canada's labor force population, aged 20 to 74. By combining employment status with perceived job insecurity, we formed four employment categories: full-time secure, full-time insecure, part-time secure, and part-time insecure. Results: Results showed no synergistic health effect between employment status and perceived job insecurity. Regardless of employment status (full-time vs. part-time), insecure employment was significantly associated with a high risk of major depressive disorder. Analysis of the interaction between gender and four flexible employment status showed a gender-contingent effect on this link in only full-time insecure category. Men workers with full-time insecure jobs were more likely to experience major depressive disorders than their women counterparts. Conclusions: This study's findings imply that perceived job insecurity may be a critical factor for developing major depressive disorder, in both men and women workers.

• 아태비즈니스연구
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• 제12권2호
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• pp.25-37
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• 2021

Purpose - This study analyzes the situational relationship between the components of job crafting and innovation performance, and based on this, suggests practical alternatives to the effect of the control variables of organizational support. Design/methodology/approach - For this survey, 350 questionnaires were distributed to Korean SME workers from October 5, 2020 to March 20, 2021, and 230 questionnaires were collected. In order to check the validity of the questionnaire, the questionnaire judged to be inappropriate in response was excluded. The recovery rate was 65.7%, and the effectiveness of the questionnaire was 82%. Structural equation model and hierarchical regression analysis are used to analyze those data. Findings - First, job enhancement through job redesign as well as organizational support is a key task in order to expect innovative results from field members. Innovative performance is not created by individual jobs, but is created between jobs and jobs, tasks and tasks, teams and teams, and departments and departments. This is why it is worth paying attention not to the functional approach, but to the interconnection structure of the process. Research implications or Originality - In this study, it was analyzed that structural job resource increase and social job resource increase, which are components of job crafting, had a positive effect on innovation performance, and that challenging job will had no significant effect. Challenging work will itself does not negatively affect innovation performance. Combining the survey and interview, field members who make up the majority of respondents say that they do not lack the will to work. They claim that there is no channel or opportunity to express or practice a challenging will.

• 대한본초학회지
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• 제38권4호
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• pp.31-43
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• 2023

Objectives : The objective of this study was to investigate the phytochemistry and pharmacological activities of Cirsium setidens. Methods : Domestic and international articles about Cirsium setidens were investigated. A review was perfoemed via DB searching engine such as Sci.Direct, Springer, DBpia, KISS, Google scholar, Kipris, and so on. Total 73 listed literature were classified by compound analysis and pharmacological efficacy. Results : C. setidens contains pectolinarin and its glycoside, pectolinarigenin as index compounds, and linarin, apigenin, diosmetin, scopoletin, acacetin, cirsimarin, cirsimaritin, setidenosides A and B, silymarin, hispidulin, 92 volatile compounds, and 15 fatty acids. The Pharmacological activities of C. setidens has been reported to inhibit of platelet aggregation and fat accumulation in the liver, inhibit to hepatitis, anti-cancer, antibacterial, skin improvement, hair growth, liver protection, anti-diabetic, anti-inflammatory, sedative. Also, It has been reported the effect of cholesterol-lowering and anti-obesity, neuroprotective effects, increasing human stem cell viability, inhibiting osteoclast formation and osteogenic differentiation. Conclusion : This reviews showed that C. setidens which has been traditionally used for the treatment of inflammation and hypertension, has anticancer and river protective effect, as well as hair loss and diet. In order to maximize the efficacy of C. setidens, research has also begun on the effect of processing processes such as fermentation or fine powdering and combining natural plant resources.

• 대한한의학방제학회지
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• 제28권1호
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• pp.53-62
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• 2020

Objective : This study is accomplished in order to investigate the effect of banggibongnyeongtang on the immunohistological change in LPS-induced depression rats to confirm the histological result of the previous behavioral and biochemical effect. Methods : LPS 5 ㎍ was injected to lateral ventricle and experimental groups were administered BBT intraperitoneally. The concentration of 5-HT in the Medial Prefrontal Cortex, Striatum, Hippocampus, Amygdala was measured by ELISA. IL-1β, TNF-α mRNA and BDNF mRNA expression in the hippocampus was examined by RT-PCR. Result : BBT enhanced 5-HT concentration at all part of brain but no significantly difference at medial prefrontal cortex and striatum. LPS+BBT400 group increased 5-HT concentration significantly than LPS group at hippocampus and amygdala (p<0.05). BBT decreased IL-1β mRNA expression dose dependently but only with significantly decrease in LPS+BBT400 group than LPS group's in Hippocampus (p<0.05). But BBT did not decrease TNF-α mRNA expression significantly in Hippocampus. BBT increased the expression of BDNF mRNA at hippocampus and LPS+BBT400 group significantly increased comparing with LPS group does (p<0.05). Conclusion : It is postulated that the anti-depressant effect of BBT can be validated through the anti-inflammatory effect, 5-HT concentration increase, and the neuro-protective effect mediated by BDNF by combining the results of the previous report about the behavioral and biochemical effect.

• Carbon letters
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• 제26권
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• pp.66-73
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• 2018

We assessed the effects of combining bio-char with straw residue mulching on the loss of soil soluble nutrients and citrus yield in sloping land. The two-year study showed that straw residue mulching (ST) and bio-char application combined with straw residue (ST+BC) can significantly reduce soil soluble nutrient loss when compared with the control treatment (CK). The comparative volume of the soil surface runoff after each of the treatments was as follows: CK > ST > ST + BC. Compared with the CK, the runoff volume of the ST was reduced by 13.6 % and 8.5 % in 2014 and 2015, respectively. Compared with the CK, combining bio-char with the ST application reduced the loss of soluble nitrogen and improved the soil total nitrogen content reaching a significant level in 2015. It dramatically increased the soil organic matter content over the two year period (36.3% in 2014, 50.6% in 2015) as well as the carbon/nitrogen ratio (C/N) (16.6% in 2014 and 39.3% in 2015). Straw mulching combined with bio-char showed a trend for increasing the citrus yield.