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        검색결과 9,685

        2761.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 SNS(social network service)를 통한 화훼상품 구매인식과 화훼상품 이미지 선호도를 알아보고자 국내 성인남녀 311명을 대상으로 설문을 진행하였다. 소비자들이 SNS를 통해 화훼상품을 구매하는 가장 큰 이유로는 트렌드에 맞는 디자인을 판매하기 때문이며, 해당 항목에 대하여 20대가 가장 높은 평균으로 나타났다. 연령에 따라 20대와 30대의 응답자는 40대에 비해 SNS를 통해 판매하는 화훼상품의 가격이 덜 합리적이라고 생각하였으며, 50대 이상의 연령에서는 SNS를 통해 판매하는 화훼상품의 품질과 꽃의 신선도에 대해 낮게 신뢰하는 것으로 나타났다. 응답자들은 SNS에 게시된 화훼 상품의 이미지가 구매할 상품 선택에 많은 도움을 준다고 인식하였으며, SNS상의 화훼상품 이미지에 대해 긍정적으로 생각하는 것을 알 수 있었다. 또한 화훼상품의 이미지가 보정효과로 다듬어진 것이라고 인식하였으나, 실제 상품과 비슷할 것이라고 생각하는 경향을 보였다. 화훼상품 구매결정에 영향을 미치는 이미지 특성으로는 전체적인 분위기가 가장 중요하다고 인식하였으며, 절화 화훼상품 이미지에서 꽃다발과 꽃바구니 화훼상품에 따라 선호하는 배경에 약간의 차이가 나타났다. 구도에 따른 선호도는 꽃다발과 꽃바구니 모두 정면에서 촬영한 이미지를 가장 선호하였으며, 이미지 보정에 대한 선호도에서는 밝은 느낌의 채도가 높은 이미지를 가장 선호하는 반면, 어두운 느낌의 이미지는 선호하지 않는 것으로 나타났다. 화훼상품 이미지 보정효과에 대한 감성인식을 의미변별척도법(semantic differential scale)에 따라 조사한 결과, 채도에 상관없이 밝은 느낌의 이미지는 ‘풍부한’, ‘세련된’, ‘고급스러운’, ‘기품 있는’과 같이 긍정적인 감성어휘 쪽이 높은 것으로 나타났다. 반면 어두운 느낌의 이미지는 전반적으로 부정적인 감성어휘 쪽이 높은 것으로 나타났다. 화훼상품 이미지의 배경, 구도, 보정효과에 따라 소비자의 선호도와 감성반응에 차이가 나타났으나, 소비자의 성별, 연령 및 직업 특성에 따른 유의한 차이는 없었다. 이를 통해, 소비자가 선호하는 이미지를 구축하여 SNS를 통한 화훼상품을 판매하는 것이 소비자들의 구매상품 선택에 도움이 될 것으로 확인되었다.
        4,300원
        2762.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The present study was designed to determine the effect of barn or cycle of grazing on changes of biochemical metabolites in prepartum and changes of milk composition in postpartum of dairy cows. For this purpose, a total of sixteen 25 months old Holstein primiparous dairy cows were allocated in two groups (n=8) with an average body weight of 571.61 ± 35.30 kg (Barn) and 578.10 ± 39.20 kg (Grazing). The study was conducted from June 2018 to October 2018. Results revealed that barn raised dairy cows had a higher increase in their serum albumin and calcium level on day 14 prepartum. However, the level of palmitic acid, saturated fatty acid increased significantly, and the level of fat, oleic acid, γ-linoleic acid, arachidonic acid and unsaturated fatty acids decreased significantly in barn raised dairy cow’s milk on day 14 postpartum. There were no significant differences observed with respect to all other biochemical metabolites, fatty acids and minerals between barn raised and cycle grazing dairy cows during prepartum and postpartum. Our study results could serve to a better understanding of barn raised cow with respect to changes of biochemical metabolites in prepartum and changes of milk composition, fatty acids and minerals content in grazing dairy cows in postpartum for estimating their physiological status.
        4,000원
        2763.
        2019.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The purpose of study was to investigate university students’ attitudes towards English language learning apps and examine whether there is any significant difference in their attitudes depending on their personal variables such as their gender, major, grade, nationality, and so on. This study also explored students’ perceptions of English language learning apps that they have used. Participants were college students living in Korea and China. Data were collected by means of a questionnaire and an interview. Results showed that both Korean and Chinese students generally held positive attitudes towards English language learning apps, although Chinese students showed more positive attitudes than Koreans. The main reasons that they liked to use English language learning apps were their convenience, ubiquity, and rich resources. On the other hands, it was revealed that the lack of communication and feedback was the main problem of using such apps. Both Korean and Chinese students stated that it was an effective way to use English language learning apps to practice pronunciation, vocabulary, listening, and reading skills. Findings of this research suggest that English language learning apps should be developed to inspire users/students’ learning interest and foster learner autonomy.
        5,500원
        2764.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Reliability analysis of the components frequently starts with the data that manufacturer provides. If enough failure data are collected from the field operations, the reliability should be recomputed and updated on the basis of the field failure data. However, when the failure time record for a component contains only a few observations, all statistical methodologies are limited. In this case, where the failure records for multiple number of identical components are available, a valid alternative is combining all the data from each component into one data set with enough sample size and utilizing the useful information in the censored data. The ROK Navy has been operating multiple Patrol Killer Guided missiles (PKGs) for several years. The Korea Multi-Function Control Console (KMFCC) is one of key components in PKG combat system. The maintenance record for the KMFCC contains less than ten failure observations and a censored datum. This paper proposes a Bayesian approach with a Dirichlet mixture model to estimate failure time density for KMFCC. Trends test for each component record indicated that null hypothesis, that failure occurrence is renewal process, is not rejected. Since the KMFCCs have been functioning under different operating environment, the failure time distribution may be a composition of a number of unknown distributions, i.e. a mixture distribution, rather than a single distribution. The Dirichlet mixture model was coded as probabilistic programming in Python using PyMC3. Then Markov Chain Monte Carlo (MCMC) sampling technique employed in PyMC3 probabilistically estimated the parameters’ posterior distribution through the Dirichlet mixture model. The simulation results revealed that the mixture models provide superior fits to the combined data set over single models.
        4,000원
        2765.
        2019.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This paper examined the use of assessment techniques in extensive reading and students’ and teachers’ perceptions on the practice of extensive reading. A total of 232 university students who were placed at different proficiency levels of classes and 13 professors participated in the study by completing a questionnaire. In-depth interviews were carried out with a selected number of student and professor volunteers. Data were analyzed using t-tests to compare two different groups of students. Results revealed that writing short answers and assessments involving discussion with peers and professor were utilized more at the basic level, but students at the basic level reported discussion with peers and professor as the most effective assessment technique. In contrast, at the intermediate level, multiple-choice questions and T/F statements were used more as assessments, but students at the intermediate level reported that writing one’s opinion on themes was the most effective technique. Both groups believed that reading graded readers is helpful in improving reading skills and vocabulary as well as understanding other cultures. Results further revealed that professors preferred to use writing short-answer questions and in-class discussion as assessments on graded readers; however, they responded that a writing task was the most adequate type of assessment. In addition, they reported that graded readers are helpful in improving all language skills and favored the use of graded readers as part of the language program.
        6,300원
        2766.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Growth factors and cytokines play an important role in delaying skin aging. However, there has been no animal stability test reported for them yet. In the present study, we examined the plausibility of Growth factor and Cytokine Mixtures (GCM) as a cosmetic ingredient by assessing skin irritation and ocular irritation for hypersensitivity using New Zealand white rabbits. Skin safety study was performed to evaluate the potential toxicity of GCM based on the irritation test. For the irritation test, GCM was applied to the rabbit skin, and no adverse reaction, such as erythema and edema, had been observed from the exposed skin sites. In the ocular irritation test, the treatment of GCM did not cause any adverse reaction on rabbit eyes, including cornea, iris, and conjunctiva tissues. From the results, both tests proved that GCM makes no irritable reaction on skin and eye mucous membrane of rabbit. Hence, it may be suggested that GCM can be safely applied as a cosmeceutical ingredient without causing any significant hypersensitivity reaction.
        4,000원
        2767.
        2019.12 구독 인증기관 무료, 개인회원 유료
        Protecting and preserving the natural and environmental treasures of Jeju Island is, eventually, the collective responsibility of the people of Jeju, all levels of the government, corporate and the environmental NGO sectors. Jeju Island has a vibrant environmental NGO sector with about 80 NGOs providing a variety of active environmental services. All efforts and services to conserve the environment of Jeju Island for the benefits of future generations need to be galvanized within the overarching environmental governance where all three sectors actively participate and make collective decisions within the three key elements of sustainable development: people, planet & profit. The key ingredient for promoting networking and collaborative opportunities between environmental NGOs, government entities and corporations is to improve their trust on one another. Given the current status of environmental NGOs - governments - corporations relations, it will take time to develop such trust, but if small measures are undertaken, mutual understanding & respect between the leaders of NGOs, government and corporations will grow and eventually result in mutual trust.
        4,800원
        2768.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To attenuate and control the spread of infectious disease, a body of research has been conducted to generate safe vaccines and to continue national-level surveillance. However, understanding on viability and persistence of avian influenza virus (AIV) in infected carcasses, and effective disposal approaches are still limited up to date. Here, using HA test and RT-PCR, we assessed active status of AIV and degradation of viral RNA in collected specimens at different sites and time points. First, AIV infectivity was recovered until day 2, and viral nucleic acids persisted to day 14 and 21 in inorganic and organic samples, respectively, in sealed vials incubated at room temperature. Second, AIV was totally inactivated in all examined specimens, and viral RNA was not detectable at all time points tested at least one month post-infection in AIV-inoculated carcasses buried directly in soil or fiber reinforced plastic (FRP) bin. Lastly, among different burial sites in South Korea, 6 out of 17 sampling sites in Jeonbuk province showed the presence of viral genetic materials, while the rest of the field samples displayed neither the presence of infective AIV nor detectable viral RNA. This study showed a linear relation between time and degradation degree of viral RNA in buried samples suggesting that burial disposal method is effective for the control or at least attenuation of spread of AI infection in infected animals although consistent monitoring is required to verify safety of disposal.
        4,000원
        2769.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 학교 장면에서 학생지도 시 교사의 상업용 온라인 게임 활용 의사에 영향을 미치는 요인이 무엇인지, 그리고 각 요인들이 어떠한 영향을 미치는지를 알아보기 위해 수행되었다. 이를 위해 면대면 설문조사를 실시하였고, 전국 초, 중, 고등학교 교사와 상담교사, 전문 상담사, 총 236명의 자료가 분석되었다. 교사의 인구통계학적 특성과 교사의 상업용 온라인 게임 활용 의사의 관련성을 분석해본 결과, 남성보다 여성교사가, 교사의 연령이 높고 근무 기간이 길수록 상업용 온라인 게임 활용 의사가 낮은 것으로 확인되었다. 교사의 상업용 온라인 게임 활용 의사에 영향을 미치는 요인을 중다회귀분석방법을 통해 분석한 결과, 교사의 개방성과 디지털 게임에 대한 태도 중 디지털 게임의 유익성에 대한 인식, 디지털 미디어 활용능력이 학생지도 시 교사의 상업용 온라인 게임 활용 의사에 정의 영향을 미치는 것으로 확인되었다. 본 연구는 교과학습 및 학생 생활 지도에 있어 교육적 잠재력을 가지고 있는 상업용 온라인 게임에 대한 교사의 활용 의사를 촉진하는 주요 요인들을 밝혔다는데 그 의의가 있다.
        4,300원
        2770.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 선진국을 중심으로 소프트웨어(SW) 교육의 중요성에 대한 연구는 계속 쏟아져 나오고 있다. 단순히 프로그래밍 언어를 습득한다는 개념을 넘어서서 논리적 사고력, 문제 해결력 등의 향상을 목적으로 한 SW 교육은 SW 교육 플랫폼을 중심으로 다양하게 개발, 연구되어 지고 있다. 본 연구에서는 컴퓨터를 활용한 SW 학습 플랫폼을 SW 교육을 처음 접하는 학습자들에게 적용하여 SW 교육 플랫폼의 중요성과 효과적인 SW 교육 플랫폼의 요소에 대해 고찰하고 학생들의 동기부여와 참여도를 높이기 위해 게임화 된 학습의 필요성에 대해 논하고자 한다.
        4,000원
        2771.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Discrete-time Queueing models are frequently utilized to analyze the performance of computing and communication systems. The length of busy period is one of important performance measures for such systems. In this paper, we consider the busy period of the Geo/Geo/1/K queue with a single vacation. We derive the moments of the length of the busy (idle) period, the number of customers who arrive and enter the system during the busy (idle) period and the number of customers who arrive but are lost due to no vacancies in the system for both early arrival system (EAS) and late arrival system (LAS). In order to do this, recursive equations for the joint probability generating function of the busy period of the Geo/Geo/1/K queue starting with n, 1≤n≤K, customers, the number of customers who arrive and enter the system, and arrive but are lost during that busy period are constructed. Using the result of the busy period analysis, we also numerically study differences of various performance measures between EAS and LAS. This numerical study shows that the performance gap between EAS and LAS increases as the system capacity K decrease, and the arrival rate (probability) approaches the service rate (probability). This performance gap also decreases as the vacation rate (probability) decrease, but it does not shrink to zero.
        4,800원
        2772.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Lately, there have been tremendous shifts in the business technology landscape. Advances in cloud technology and mobile applications have enabled businesses and IT users to interact in entirely new ways. One of the most rapidly growing technologies in this sphere is business intelligence, and associated concepts such as big data and data mining. BI is the collection of systems and products that have been implemented in various business practices, but not the information derived from the systems and products. On the other hand, big data has come to mean various things to different people. When comparing big data vs business intelligence, some people use the term big data when referring to the size of data, while others use the term in reference to specific approaches to analytics. As the volume of data grows, businesses will also ask more questions to better understand the data analytics process. As a result, the analysis team will have to keep up with the rising demands on the infrastructure that supports analytics applications brought by these additional requirements. It’s also a good way to ascertain if we have built a valuable analysis system. Thus, Business Intelligence and Big Data technology can be adapted to the business’ changing requirements, if they prove to be highly valuable to business environment.
        4,000원
        2773.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Extant research has proposed that the Object-Spatial-Verbal cognitive style can elucidate individual differences in the preference for modality-specific information. However, no studies have yet ascertained whether this type of information processing evinces structural correlations in the brain. Therefore, the current study used voxel-based morphometry (VBM) analyses to investigate individual differences in gray matter volumes based on the Object-Spatial-Verbal cognitive style. For this purpose, ninety healthy young adults were recruited to participate in the study. They were administered the Korean version of the Object-Spatial-Verbal cognitive style questionnaire, and their anatomical brain images were scanned. The VBM results demonstrated that the participants’ verbal scores were positively correlated with regional gray matter volumes (rGMVs) in the right superior temporal sulcus/superior temporal gyrus, the bilateral parahippocampal gyrus/fusiform gyrus, and the left inferior temporal gyrus. In addition, the rGMVs in these regions were negatively correlated with the relative spatial preference scores obtained by individual participants. The findings of the investigation provide anatomical evidence that the verbal cognitive style could be decidedly relevant to higher-level language processing, but not to basic language processing.
        4,000원
        2774.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Currently many companies are interested in reduction of the carbon emissions associated with their supply chain activities such as transportation and operations. Operational decisions, such as modifications in order quantities could an effective way in reducing carbon emissions in the supply chain. Cap-and-trade regulation, sometimes called emissions trading, is a market-based tool to limit greenhouse gas emissions. Under cap-and-trade regulation, emission credits are allocated to the firms and the firms trades emissions under cap-and-trade schemes. In this paper, we propose a single-manufacturer single-buyer two-echelon supply chain problem under the cap-and-trade mechanism incorporating the carbon emissions caused by transportation and warehousing activities where a single manufacturer produces a family of items in order to deliver a family of items to a single buyer at a fixed interval of time for effective implementation of Just-In-Time (JIT) Purchasing. An integrated multi-product lot-splitting model of facilitating multiple shipments in small lots between buyer and manufacturer is developed in a JIT Purchasing environment. Also, an iterative heuristic algorithm is developed to derive the common order interval, the number of intervals for each product and the number of shipments between the buyer and the manufacturer during the common interval. A numerical example is given to illustrate the savings in reduction of total cost and carbon emissions by the inventory model incorporating cap-and-trade mechanism compared to the classical inventory model. The proposed inventory model could be useful for the practical solution of two-echelon supply chain inventory problem under cap-and-trade mechanism.
        4,000원
        2775.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        가상현실 콘텐츠는 ICT 기술의 발전과 5G의 고용량 전송, 빠른 속도의 네트워크 서비스가 상용화로 2019년 빠른 성장을 하고 있다. 하지만 가상현실 콘텐츠의 사용성 평가에 대한 기준과 연구는 미흡한 실정이다. 본 연구에서는 가상현실 콘텐츠를 사용하는 사용자의 반응과 상태를 측정 할 수 있는 객관성이 있는 데이터에 관한 연구를 진행한다. 연구의 방법으로는 가상현실 게임 콘텐츠 사용자의 실시간 인체정보 수집 프로세스를 설계하고의 변화를 비교·분석하였다. 이를 위해 인체정보 측정에 아이트래킹을 통한 시선 정보와 심박수 데이터를 수집하고 분석하여 시각화 솔루션을 설계하고 프로토타입을 구현하였다. 가상현실 게임 콘텐츠 사용자 인체정보 데이터를 기반으로 한 사용성 평가에 대한 가이드를 제안한다. 향후연구로는 다양한 인체정보 측정 및 프로토타입의 고도화에 있다.
        4,000원
        2776.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        현재 출시된 중국어 학습 기능성 게임 및 관련 학술 연구는 많지만 대부분 스마트폰 플랫폼에서 수행되었으며 VR플랫폼 기반 학술 연구와 게임 개발이 많지 않다. 그러나 현재 VR기능성 게임은 가상현실 공간의 몰입적 체험이 학습효과를 확실히 높일 수 있다는 연구가 이미 존재한다. ‘Classroom Simulation’은 가상현실 공간의 시뮬레이션 강의실에서 수업과 게임을 하는 중국어 일상어를 배우는 기능성 게임이다. 이 게임은 중국어 초보자와 중국으로 여행을 가려는 외국인을 대상으로 이들이 중국어 일상어를 알아듣고 말할 수 있는것을 목적으로 개발하였다. 이러한 단일적 교육 목적으로 본 연구는 맞춤형 게임 시스템 설계를 진행하였다. 본 연구에서 중국어 일상어 교육용 기능성 게임을 구성하기 위하여 시뮬레이션 강의실과 교사를 구현하였으며 3가지 레벨의 게임플레이 설계에 대해서 소개하였다. 이 게임의 교육 효과와 효율성, 오락성을 검증하기 위하여 12명의 실험자를 선발하여 실험을 진행하였다. 실험 결과에 따르면 이 게임의 교육 효과와 효율성이 입증된 반면 게임 시나리오와 게임플레이 등 오락성 측면에서 미흡하다고 나타났다. 실험과 결과 분석을 바탕으로 개선 방안에 대해 검토했으며 향후 연구를 진행하고자 한다.
        4,000원
        2777.
        2019.12 구독 인증기관 무료, 개인회원 유료
        The study aims to assess the use of social networking sites among Educational Technology (Edtech) students of Philippine Normal University Visayas. Descriptive method was used. A total of 95 respondents participated, 27 were males and 68 were females. The statistics used were: frequency, percentage weighted mean, and rank. The top three uses of social networking in the personal life of the respondents according to rank are: 1) to connect with people, 2) to do research, and 3) to e-mail people. With regard to its use in their academic life, the top three are: 1) to do research, 2) to e-mail, and 3) to connect with people. The social networking sites which ranked number one as being used by the respondents are Google for research, Yahoo for e-mail, Facebook for connecting with people and OLX for purchasing. The study disclosed that the respondents “agree” with the benefits of social networking. It was concluded based on the findings of the study that there are social networking sites used to a high extent by the respondents. However, they are limited only to Facebook, Google and Yahoo. The foremost use of social networking is for researching, chatting and messaging and uploading and downloading. Furthermore, it was concluded that the respondents are aware that social networking has both benefits and risks. The researcher recommends the following: the students should be given trainings and workshops on the effective use of social networking; the teachers should monitor the social networking done by their students for purposes of proper guidance and information.
        4,200원
        2778.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        오늘날, 정보 기술은 급속도로 발전하고 있으며 기존의 인터랙션 디자인은 더 이상 사용자의 요구를 충족 시키지 못하며 사용자들은 사용자 체험에 대해 더 까다로운 요구를 하고 있다. 사용자 체험의 개념은 이미 디자인의 목적으로 가용성, 용이성에서 감정, 의미의 의도로 확장하고 있다. 감정 인터랙션 디자인은 정보시대 연구자와 디자이너의 관심의 초점이 되어가고 있으며, 이용자 체험 디자인의 새로운 트렌드가 되고 있다. 이런 상황에서 사용자의 정서적 욕구를 충족시키는 것이 중요하다. 본 연구는 기존 카드게임의 사례를 들어 논증하는 방법으로 트레이딩 카드게임에 존재하는 감정 인터랙션 디자인 및 관련 디자인을 분석하였다. 또한 공통적으로 분석 결과를 정리하여 이를 바탕으로 감정 인터랙션 디자인이 트레이딩 카드게임에서 어떤 역할을 하는지 입증했다. 플레이어가 게임을 하면서 느끼는 감정적인 요소를 통해 감정 인터랙션이 게임 디자인에서 갖는 중요한 가치를 밝히고, 디자이너가 게임 디자인을 하면서 감정 인터랙션 디자인을 얼마나 중요시하는지를 보여준다.
        4,300원
        2779.
        2019.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This article reports on a classroom-based study that examined the effects of direct focused and unfocused written corrective feedback (WCF) on the accuracy development of the past hypothetical conditional (e.g., If I had had money, I would have bought a new computer.) and the indefinite article (a/an). The study employed a pretest-posttest-delayed posttest design with two feedback treatment sessions. Six intermediate classes, a total of 108 college freshmen at a university in Korea and two native English speaking instructors, participated in the study. The classes were assigned into a focused WCF group, an unfocused WCF group, and a control group. A text-reconstruction task was used as a writing material and a test instrument. The results revealed that both focused and unfocused WCF groups outperformed the control group in the accuracy gains of both target forms. When the relative effects of two types of feedback were considered, there was no difference in the contribution focused and unfocused WCF made for the accuracy improvement of the hypothetical conditional. However, focused WCF was more beneficial than unfocused WCF for the development of the indefinite article.
        5,800원
        2780.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        After Dantzig and Rasmer introduced Vehicle Routing Problem in 1959, this field has been studied with numerous approaches so far. Classical Vehicle Routing Problem can be described as a problem of multiple number of homogeneous vehicles sharing a same starting node and having their own routes to meet the needs of demand nodes. After satisfying all the needs, they go back to the starting node. In order to apply the real world problem, this problem had been developed with additional constraints and pick up & delivery model is one of them. To enhance the effectiveness of pick up & delivery, hub became a popular concept, which often helps reducing the overall cost and improving the quality of service. Lots of studies have suggested heuristic methods to realize this problem because it often becomes a NP-hard problem. However, because of this characteristic, there are not many studies solving this problem optimally. If the problem can be solved in polynomial time, optimal solution is the best option. Therefore, this study proposes a new mathematical model to solve this problem optimally, verified by a real world problem. The main improvements of this study compared to real world case are firstly, make drivers visit every nodes once except hub, secondly, make drivers visit every nodes at the right time, and thirdly, make drivers start and end their journey at their own homes.
        4,000원