• 대한의생명과학회지
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• 제28권4호
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• pp.211-222
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• 2022

After more than two years of efforts to end the corona pandemic, a gradual recovery is starting in countries with high vaccination rates. Easing public health policies for a full-fledged post-corona era, such as lifting the mandatory use of outdoor mask and quarantine measures in entry have been considered in Korea. However, the continuous emergence of new variants of SARS-CoV-2 and limitations in vaccine efficacy still remain challenging. Fortunately, T cells and memory T cells, which are key components of adaptive immunity appear to contribute substantially in COVID-19 control. SARS-CoV-2 specific CD4⁺/CD8⁺ T cells are induced by natural infection or vaccination, and rapid induction and activation of T cells is mainly associated with viral clearance and attenuated clinical severity. In addition, T cell responses induced by recognition of a wide range of epitopes were minimally affected and conserved against the highly infectious subsets of omicron variants. Polyfunctional SARS-CoV-2 specific T cell memory including stem cell-like memory T cells were also developed in COVID-19 convalescent patients, suggesting long lasting protective T cell immunity. Thus, a robust T-cell immune response appears to serve as a reliable and long-term component of host protection in the context of reduced efficacy of humoral immunity and persistent mutations and/or immune escape.

• Ocean Systems Engineering
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• 제12권1호
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• pp.63-86
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• 2022

A refined projection-based purely Lagrangian meshfree method is presented towards reliable numerical analysis of fluid flow interactions with saturated/unsaturated porous media of uniform/spatially-varying porosities. The governing equations are reformulated on the basis of two-phase mixture theory with incorporation of volume fraction. These principal equations of mixture are discretized in the context of Incompressible SPH (Smoothed Particle Hydrodynamics) method. Associated with the consideration of governing equations of mixture, a new term arises in the source term of PPE (Poisson Pressure Equation), resulting in modified source term. The linear and nonlinear force terms are included in momentum equation to represent the resistance from porous media. Volume increase of fluid particles are taken into consideration on account of the presence of porous media, and hence multi-resolution ISPH framework is also incorporated. The stability and accuracy of the proposed method are thoroughly examined by reproducing several numerical examples including the interactions between fluid flow and saturated/unsaturated porous media of uniform/spatially-varying porosities. The method shows continuous pressure field, smooth variations of particle volumes and regular distributions of particles at the interface between fluid and porous media.

• International journal of advanced smart convergence
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• 제11권4호
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• pp.104-119
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• 2022

Life safety awareness level diagnosis is necessary for customized safety education and continuous safety awareness. As the starting stage of safety education for each life cycle, a scale that has verified the reliability and validity of high school students' life safety awareness has not yet been developed. In this context, the purpose of this study is to develop and validate the life safety awareness scale of high school students and to analyze interindividual differences. Questionnaire data was collected from April to June 2022 from 834 students in the first, second, and third grades of high schools in △△ city in Jeollabuk-do. A final 25-item scale was developed using the preliminary survey, preliminary test, the main test, descriptive statistical analysis, and exploratory and confirmatory factor analysis. This scale consists of four sub-factors: 'safety prevention', 'safety knowledge', 'safety preparation', and 'safety protection'. Good reliability and validity were verified by analysis of content validity and construct validity. The generalizability of the scale was verified by crossover validation between the search group and the crossover group. Based on the interindividual differences analysis, although there was a difference between genders in life safety awareness, there was no difference by grade level and academic achievement. This study is significant in developing the first valid scale that can measure high school students' life safety awareness and providing the necessity and rationale for life safety education by life cycle considering individual gender differences.

• 한국음향학회지
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• 제18권6호
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• pp.49-56
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• 1999

결정 트리 기반 상태 공유 방법은 HMM을 사용하는 많은 연속 음성 인식 시스템에서 강인하고 정확한 문맥 종속 음향 모델링 뿐만 아니라 훈련 중에는 나타나지 않은 모델들의 합성을 위하여 널리 사용되고 있다. 음성 결정 트리를 구성하기 위한 표준적인 방법은 단일 가우시안 트라이폰 모델을 이용한 1계층 프루닝 만을 사용하고 있다. 본 논문에서는 더욱 정교한 음향 모델링을 통하여 인식 성능 향상을 도모하기 위하여 새로운 2가지 접근 방법 즉, 2계층 결정 트리와 복수 혼합 결정 트리를 제안한다. 2계층 결정 트리는 상태 공유와 혼합 가중치 공유를 위하여 2계층 프루닝을 수행하며, 두 번째 계층을 사용하여 공유 상태들도 음성 문맥의 유사도에 따라서 서로 다른 가중치들을 사용할 수 있다. 두 번째 제안된 방법 에서는 훈련 과정 즉, 혼합 분할 및 재추정 과정과 함께 음성 결정 트리가 계속 갱신되어 진다. 복수 혼합 결정 트리를 구성하기 위하여 단일 가우시안 뿐만 아니라 복수 혼합 가우시안 모델이 함께 사용된다. 제안된 방법들을 이용하여 BN-96과 WSJ5k 데이터를 사용한 연속 음성 인식 실험을 수행한 결과, 표준 결정 트리를 사용한 시스템과 비교하여 공유 상태의 개수를 비슷하게 유지하면서 단어 오인식률을 줄일 수 있었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1162-1162
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• 2001

Whereas NIR spectroscopy has been applied in agriculture for more than 20 years, few studies refer to those plant substances occurring only in smaller amounts. Nevertheless there is a growing interest today to support efficiently activities in the production of high-quality medicinal and spice plants by this fast and non-invasive method. Therefore, it was the aim of this study to develop new NIR methods for the reliable prediction of secondary metabolites found as valuable substances in various plant species. First, sophisticated NIR methods were established to perform fast quality analyses of intact fennel, caraway and dill fruits deriving from single-plants [1]. Later on, a characterization of several leaf drugs and the corresponding fresh material has been successfully performed. In this context robust calibrations have been developed for dried peppermint, rosemary and sage leaves for the determination of their individual essential oil content and composition [2]. A specially adopted NIR method has been developed also for the analysis of carnosic acid in the leaves of numerous rosemary and sage gene bank accessions. Carnosic acid is an antioxidative substance for which several health promoting properties including cancer preservation are assumed. Also some other calibrations have been developed for non-volatile substances such as aspalathin (in unfermented rooibos leaves), catechins (in green tea) and echinacoside (in different Echinacea species) [3]. Some NIR analyses have also been successfully performed on fresh material, too. In spite of the fact that these measurements showed less accuracy in comparison to dried samples, the calibration equations are precise enough to register the individual plant ontogenesis and genetic background. Based on the information received, the farmers and breeders are able to determine the right harvest time (when the valuable components have reached their optimum profile) and to select high-quality genotypes during breeding experiments, respectively. First promising attempts have also been made to introduce mobile diode array spectrometers to collect the spectral data directly on the field or in the individual natural habitats. Since the development of reliable NIRS methods in this special field of application is very time-consuming and needs continuous maintenance of the calibration equations over a longer period, it is convenient to supply the corresponding calibration data to interested user via NIRS network. The present status of all activities, preformed in this context during the last three years, will be presented in detail.

• 한국지역지리학회지
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• 제13권6호
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• pp.623-638
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• 2007

본 논문은 환경 변화에 대한 기업의 동태적 적응 메카니즘을 설명하는 대조적인 두 이론을 고찰하고, 두 이론 간에 보완적 연계의 필요성을 밝히는 것이 그 목적이다. 1980년대 까지 재구조화론은 기업의 성공과 적응을 설명하는 지배적인 접근이었다. 그러나 이 접근은 환경 변화에 대해 어떻게 기업이 적응하는지, 기업들 간의 적응의 성패가 왜 상이하게 나타나는지에 대해 설명하지 않는다. 즉 재구조화론은 기업의 학습과 적응에 대한 맥락 특수적인 해석 시각을 제공하지 못한다. 한편 1990년대 이후에 기업의 학습과 진화에 대한 학문적 관심은 기업의 동태적 경쟁력을 이끄는 기업 학습의 본질을 고찰하는 것에 초점이 두어져 왔다. 조직학습론은 조직 진화에 있어 지식, 학습 그리고 역량의 중요성을 강조한다. 하지만 이 접근 또한 급진적인 환경 변화에 대한 기업의 적응 메커니즘에 대해서는 효과적으로 설명하지 못하고 있다. 본 연구는 이러한 맥락에서 기업의 동태적 적응과 진화는 재구조화 과정과 점진적 및 급진적 학습 과정의 길함을 통해 나타나는 사실을 설명하고, 이를 토대로 기업의 진화와 적응을 효과적으로 설명하기 위해서는 두 이론을 보완적으로 연계한 통합적 이론 체계가 구축될 필요가 있음을 제안한다.

• International Journal of Computer Science & Network Security
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• 제21권8호
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• pp.71-78
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• 2021

The relevance of research provides the necessity to identify the basic problems in the public governance sphere and information technology relations, forasmuch as understanding such interconnections can indicate the consequences of the development and spreading information technologies. The purpose of the research is to outline the issues of applying information technologies in public governance sphere. 500 civil servants took part in the survey (Ukraine). A two-stage study was conducted in order to obtain practical results of the research. The first stage involved collecting and analyzing the responses of civil servants on the Mentimeter online platform. In the second stage, the administrator used the SWOT-analysis system. The tendencies in using information technologies have been determined as follows: the institutional support development; creation of analytical portals for ensuring public control; level of accountability, transparency, activity of civil servants; implementation of e-government projects; changing the philosophy of electronic services development. Considering the threats and risks to the public governance system in the context of applying information technologies, the following aspects generated by societal requirements have been identified, namely: creation of the digital bureaucracy system; preservation of information and digital inequality; insufficient level of knowledge and skills in the field of digital technologies, reducing the publicity of the state and municipal governance system. Weaknesses of modern public governance in the context of IT implementation have been highlighted, namely: "digitization for digitalization"; lack of necessary legal regulation; inefficiency of electronic document management (issues caused by the imperfection of the interface of reporting interactive forms, frequent changes in the composition of indicators in reporting forms, the desire of higher authorities to solve the problem of their introduction); lack of data analysis infrastructure (due to imperfections in the organization of interaction between departments and poor capacity of information resources; lack of analytical databases), lack of necessary digital competencies for civil servants. Based on the results of SWOT-analysis, the strengths have been identified as follows: (possibility of continuous communication; constant self-learning); weaknesses (age restrictions for civil servants; insufficient acquisition of knowledge); threats (system errors in the provision of services through automation); opportunities for the introduction of IT in the public governance system (broad global trends; facilitation of the document management system). The practical significance of the research lies in providing recommendations for eliminating the problems of IT implementation in the public governance sphere outlined by civil servants..

• 지식경영연구
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• 제23권4호
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• pp.275-294
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• 2022

최근 몇 년 동안 전자상거래와 소셜미디어의 지속적인 통합 발전과 함께 소셜커머스는 신뢰 중심의 사회적 거래 방식으로서 전자상거래의 중요한 형태로 자리를 잡았다. 온라인 커뮤니티의 긍정적인 측면과 풍부한 사용자 제작 콘텐츠 (UGC)로 인해 커뮤니티에 참여하는 사용자와 기업이 점점 더 증가하고 있는 추세이다. 이러한 상황에서 정보접근 비용은 지속적으로 감소하고 있고 구매 프로세스는 보다 간결하고 효율적으로 개선되고 있는 반면에 소비자의 충동구매 가능성을 크게 높이는 결과를 가져오게 된다. 그럼에도 불구하고 아직까지 소셜커머스에서 UGC의 특성을 기반으로 한 소비자 충동구매의 메커니즘에 대한 실증적 연구는 거의 없다. 본 연구는 자극-유기체-반응 (S-O-R) 모델을 이용하여 소셜커머스에서 UGC 특성이 소비자 충동구매에 미치는 영향을 분석하는 연구모형을 구축하였고, 이 과정에서 지각된 위험을 매개변수로, 유대강도를 조절변수로 각각 설정하였다. 실증분석 결과 콘텐츠 진정성, 콘텐츠 유용성, 그리고 콘텐츠 가치는 구매의사결정 과정에서 소비자의 지각된 위험에 유의한 영향을 미치고, 소비자의 지각된 위험은 충동구매에 유의한 영향을 미치는 것으로 나타났다. 한편, UGC 생산자와 이용자 간의 유대강도는 콘텐츠 유용성과 지각된 위험의 관계 및 지각된 위험과 충동구매 관계를 조절하는 것으로 나타났다. 이러한 연구결과는 소셜커머스 사업자들로 하여금 고객의 소비행동에 대한 심층적인 이해를 도울 뿐만 아니라 소비자 충동구매가 왜 일어나는지에 대한 메커니즘을 학술적 관점에서 분석할 수 있는 이론적 틀을 제공하였다는 점에서 의의가 있다.

• 대한교통학회지
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• 제22권5호
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• pp.139-149
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• 2004

급격히 증가하는 차량수요에 대응하기 위하여 도로의 공급을 증대시키는 양적인 측면의 도로정책 기조가 유지되고 있지만, 이는 근본적인 해결책이 될 수 없다는 인식이 대두되어 왔다. 이에 따라 기존 도로시설의 효율적 활용과 교통수요를 관리하는 방법에 많은 관심이 모아지고 있다. 이중 혼잡통행료는 수요를 관리하고 차량을 도로량에 적절히 배정하는 수단으로 생각될 수 있으며, 교통 혼잡과 환경에 대한 악영향을 줄일 수 있는 가장 효율적인 방법중 하나로 고려되고 있다. 이에 따라 혼잡통행료 산정문제는 그동안 경제학자와 교통전문가에게 중요하고 흥미로운 연구 분야로 여겨져 왔고 다양한 방법으로 연구가 이루어져 왔다. 본 연구에서는 이러한 혼잡통행료 산정문제를 네트워크 설계문제(Network Design Problem, NDP)로 보고 통행배정문제와 혼잡통행료 산정 최적화 문제가 결합된 바이레벨 문제(Bi-level Problem)로 모형을 개발하였다. 여기서, 통행배정문제는 혼잡통행료 징수에 따른 통행자의 행태변화를 고려하기 위하여 Sheffi(1985)가 제시하였던 가변수요모형(Elastic-Demand Network Equilibrium Model)을 적용하였고, 혼잡통행료 산정 최적화 문제로서 사회적 순 편익 최대화문제를 고려하였다. 또한, 이런 형태의 바이레벨 문제는 게임이론측면에서 보면, 두 문제간의 비협력을 전제로 하는 Nash 비협력 게임과 상호 협력을 전제하는 Stackelberg게임으로 구분할 수 있는데, 본 연구에서는 민감도 분석을 통하여 최적해를 찾는 Stackelberg 게임으로 모형을 개발하였다. 통행수요는 단일계층으로 승용차로만 구성되어있다고 가정하였으며, 개발된 모형에 대하여 2개 네트워크에서 실험이 이루어졌다. 실험을 통하여 모형의 알고리즘에 관한 설명과 검증을 하였으며, 혼잡통행료 산정문제와 함께 적합한 혼잡통행료 징수 대상 링크의 선정이 중요한 연구대상임을 제시하였다.

• World Technopolis Review
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• 제8권2호
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• pp.74-81
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• 2019

Cities will soon host two third of the population worldwide, and already today 80% of the world energy is used in the 20 largest cities. Urban areas create 80% of the greenhouse gas emission, so we should take care that urban areas are smart and sustainable as implementations have especially here the greatest impact. Smart Cities (SC) or Smart Sustainable Cities (SSC) are the actual concepts that describe methodologies how cities can handle the high density of citizens, efficiency of energy use, better quality of life indicators, high attractiveness for foreign investments, high attractiveness for people from abroad and many other critical improvements in a shifting environment. But if we talk about Entrepreneurship Ecosystem and Innovation, we do not see a lot of literature covering this topic within those SC/SSC concepts. It seems that 'Smart' implies that all is embedded, or isn't it properly covered as brick stone of SC/SSC concepts, as they are handled in another 'responsibility silo', meaning that the policy implementation of a Science and Technology Park (STP) is handled in another governing body than SC/SSC developments. If this is true, we will obviously miss a lot of synergy effects and economies of scale effects. Effects that we could have in case we stop the siloed approaches of STPs by following a more holistic concept of a Smart Sustainable City, covering also a continuous flow of innovation into the city, without necessarily always depend on large corporate SSC solutions. We try to argue that every SSC should integrate SP/STP concepts or better their features and services into their methodology. The very limited interconnectivity between these concepts within the governance models limits opportunities and performance in both systems. Redesigning the architecture of the governance models and accepting that we have to design a system-of-systems would support the possible technology flow for smart city technologies, it could support testbed functionalities and the public-private partnership approach with embedded business models. The challenge is of course in complex governance and integration, as we often face siloed approaches. But real SSC are smart as they are connecting all those unconnected siloes of stakeholders and technologies that are not yet interoperable. We should not necessarily follow anymore old greenfield approaches neither in SSCs nor in SP and STP concepts from the '80s that don't fit anymore, being replaced by holistic sustainability concepts that we have to implement in any new or revised SSC concepts. There are new demands for each SP/STP being in or close to an SC/SCC as they have a continuous demand for feeding the technology base and the application layer and should also act as testbeds. In our understanding, a big part of STP inputs and outputs are still needed, but in a revised and extended format. We know that most of the SC/STP studies claim the impact is still far from understood and often debated, therefore we must transform the concepts where SC/STPs are not own 'cities', but where they act as technology source and testbed for industry and new SSC business models, being part of the SC/STP concept and governance from the beginning.