• Title/Summary/Keyword: Demand guarantee

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In-Sample and Out-of-Sample Predictability of Cryptocurrency Returns

  • Kyungjin Park;Hojin Lee
    • East Asian Economic Review
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    • v.27 no.3
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    • pp.213-242
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    • 2023
  • This paper investigates whether the price of cryptocurrency is determined by the US dollar index, the price of investment assets such gold and oil, and the implied volatility of the KOSPI. Overall, the returns on cryptocurrencies are best predicted by the trading volume of the cryptocurrency both in-sample and out-of-sample. The estimates of gold and the dollar index are negative in the return prediction, though they are not significant. The dollar index, gold, and the cryptocurrencies seem to share characteristics which hedging instruments have in common. When investors take notice of the imminent market risks, they increase the demand for one of these assets and thereby increase the returns on the asset. The most notable result in the out-of-sample predictability is the predictability of the returns on value-weighted portfolio by gold. The empirical results show that the restricted model fails to encompass the unrestricted model. Therefore, the unrestricted model is significant in improving out-of-sample predictability of the portfolio returns using gold. From the empirical analyses, we can conclude that in-sample predictability cannot guarantee out-of-sample predictability and vice versa. This may shed light on the disparate results between in-sample and out-of-sample predictability in a large body of previous literature.

A Study on the Low-Floor Bus Route Selection Considering a Residential Distribution and Traffic Characteristics of the Transportation Vulnerable - A Case of Busan - (교통약자의 거주 분포와 통행특성을 고려한 저상버스 노선 선정 - 부산시를 사례로 -)

  • PARK, Ji-Ho;NAM, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.2
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    • pp.161-173
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    • 2015
  • The guarantee of transportation for elderly and handicapped people is increasingly necessary owing to their growing social and economic activity. In March of 2013, a partial amendment to the law for transportation of the vulnerable was made by the government, to make more convenient transport a legal requirement. The amendment describes standards for the installation of transport facilities, and its support available. However, the adjustment of low-floor bus routes is not included. Therefore, low-floor buses are operating without consideration for the handicapped. This study evaluates the current low-floor bus system user experience by considering the residential distribution of vulnerable customers and analyzing their reasons for using public transport. As a result of this work, adjustments to current bus routes are proposed. The residential distribution of vulnerable people has been assessed using the supporting materials of the urban renewal project in Busan City, and their reasons for using public transport have been collected by a survey of the target user groups. The results show that group A, which has good accessibility, was in high demand, but provided the most limited service. Whereas group C, which also has good accessibility but was in low demand, provided its service most frequently. The data show the supply and demand inconsistencies of low-floor buses, and the inefficiency of bus route allocation. Therefore, this study proposes improvements to current methods for the effective operation of low-floor buses.

Analysis of Demand and Job Impact according to Application of Chaperone Practices in Radiation Work (방사선 업무에서 샤프롱제도 적용에 따른 요구도 및 직무 영향 분석)

  • Kim, Jeong-Ho
    • Journal of Digital Convergence
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    • v.20 no.4
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    • pp.449-457
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    • 2022
  • The chaperone practices is being applied to solve the problem of sexual harassment in clinics in medical institutions. Therefore, considering the characteristics of the radiation work and the application of the chaperone practices in the radiation work, this study is to analyze the requirements for the application of the chaperone practices and the impact that may occur on the job. From the end of 2021 to the beginning of 2022, a survey was conducted targeting radiologists in Daegu and Gyeongbuk, and about 52.9% of the surveys were analyzed. As a result of the analysis, the demand for the application of the chaperone practices was higher among women than men, the younger the age, the higher the degree, and the lower the age. Also, as for the job impact of the application of the chaperone practices, the higher the demand, the greater the reduction in sexual harassment and credibility. In other words, the younger the age and the higher the education, the higher the need for the chaperone practices, but it is thought that it is necessary to supplement the policy for job security and Employment stability before applying it. Therefore, when considering the application of the chaperone practices to radiation work in the future, it is judged that it is necessary to sufficiently collect opinions in advance to guarantee the job in the relevant occupation.

A Survey of Radiologic Science Students' Awareness and Educational Needs of Forensic Medicine (방사선학과 전공 학생들의 법의학에 대한 인식과 교육 요구도 조사)

  • Kyeong-Hwan Jeong;Sang-Hyun Han
    • Journal of the Korean Society of Radiology
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    • v.17 no.6
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    • pp.977-983
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    • 2023
  • Due to the development of the domestic economy and science, the people's standard of living has increased. Accordingly, we want to improve the quality of life. In other words, we guarantee human rights and pursue dignity and value as human beings. Therefore, the medical field extends human life and helps maintain a healthy life. The social medicine that protects human rights is forensic medicine. Forensic medicine identifies deaths and analyzes the cause using forensic radiology images. Forensic radiology is the acquisition and provision of medical images by the radiographer. Therefore, the radiographer must have expertise by completing forensic science-related courses. Recently, medical and nursing schools have opened and operated various subjects such as forensic medicine and forensic nursing. However, the Department of Radiology science is the only school that offers courses related to forensic science. For the future development and exploration of the radiographer and department of radiology science, forensic education should be considered. For this purpose, we investigated the necessity and demand for forensic education in the department of radiology science undergraduate and graduate schools. The department of radiology science students' awareness of forensic science was found to be 2.977 points, but the need for forensic science education for the radiographer was high at 3.759 points. In addition, current students' demand for forensic science courses was high at 84.1%, with the majority responding that it was necessary to open and operate the course. This study was able to determine the demand for forensic science-related subjects among the department of radiology science undergraduate and graduate students, and there is a need to explore diversity and expertise in education. We hope that it will be used as basic data for the development of forensic medicine and radiology science.

A Study on the Power Supply and Demand Policy to Minimize Social Cost in Competitive Market (경쟁시장 하에서 사회적 비용을 고려한 전력수급정책 방향에 관한 연구)

  • Kwon, Byung-Hun;Song, Byung Gun;Kang, Seung-Jin
    • Environmental and Resource Economics Review
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    • v.14 no.4
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    • pp.817-838
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    • 2005
  • In this paper, the resource adequacy as well as the optimum fuel mix is obtained by the following procedures. First, the regulation body, the government agency, determine the reliability index as well as the optimum portfolio of the fuel mix during the planning horizon. Here, the resources with the characteristics of public goods such as demand-side management, renewable resources are assigned in advance. Also, the optimum portfolio is determined by reflecting the economics, environmental characteristics, public acceptance, regional supply and demand, etc. Second, the government announces the required amount of each fuel-type new resources during the planning horizon and the market participants bid to the government based on their own estimated fixed cost. Here, the government announces the winners of the each auction by plant type and the guaranteed fixed cost is determined by the marginal auction price by plant type. Third, the energy market is run and the surplus of each plant except their cost (guaranteed fixed cost and operating cost) is withdrew by the regulatory body. Here, to induce the generators to reduce their operating cost some incentives for each generator is given based on their performance. The performance is determined by the mechanism of the performance-based regulation (PBR). Here the free-riding performance should be subtracted to guarantee the transparent competition. Although the suggested mechanism looks like very regulated one, it provides two mechanism of the competition. That is, one is in the resource construction auction and the other is in the energy spot market. Also the advantages of the proposed method are it guarantee the proper resource adequacy as well as the desired fuel mix. However, this mechanism should be sustained during the transient period of the deregulation only. Therefore, generation resource planning procedure and market mechanisms are suggested to minimize possible stranded costs.

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A Flow Control Scheme for the QoS Improvement of Multi-Service using IPv6 Hop-by-Hop Option Header (IPv6 홉-바이-홉 옵션 헤더 이용으로 멀티서비스의 QoS 개선을 위한 플로우 제어 방안)

  • 이인화;김성조
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.2B
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    • pp.250-262
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    • 2004
  • In IPv6 environment, the Internet Telephony, VoD(Video on Demand) and high capacity file exchange service will be more increased than IPv4. Therefore, the strict guarantee of QoS based on End-to-End and differentiated quality control schemes are simultaneously required. This paper proposes the flow control schemes on IPv6 network that the traffic is identified by flow and the QoS of multi-service is improved by QoS information in IPv6 hop-by-hop option header. The object of flow control includes not only non-default QoS traffic, which uses the flow label, but also best-effort or encrypted traffic. Therefore, the guarantee of real-time service is strengthened and the flow, which abuses unnecessarily the network resources, is effectively controlled. Also, this paper proposes the mapping scheme between the flow and MPLS by reflecting the minimum change of the existed network resource and the status of backbone network of ISP(Internet Service Provider). In the simulation result, It is shown that the proposed scheme is effective in the side of QoS on real-time services and utilization of backbone resources.

BEEF MEAT TRACEABILITY. CAN NIRS COULD HELP\ulcorner

  • Cozzolino, D.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1246-1246
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    • 2001
  • The quality of meat is highly variable in many properties. This variability originates from both animal production and meat processing. At the pre-slaughter stage, animal factors such as breed, sex, age contribute to this variability. Environmental factors include feeding, rearing, transport and conditions just before slaughter (Hildrum et al., 1995). Meat can be presented in a variety of forms, each offering different opportunities for adulteration and contamination. This has imposed great pressure on the food manufacturing industry to guarantee the safety of meat. Tissue and muscle speciation of flesh foods, as well as speciation of animal derived by-products fed to all classes of domestic animals, are now perhaps the most important uncertainty which the food industry must resolve to allay consumer concern. Recently, there is a demand for rapid and low cost methods of direct quality measurements in both food and food ingredients (including high performance liquid chromatography (HPLC), thin layer chromatography (TLC), enzymatic and inmunological tests (e.g. ELISA test) and physical tests) to establish their authenticity and hence guarantee the quality of products manufactured for consumers (Holland et al., 1998). The use of Near Infrared Reflectance Spectroscopy (NIRS) for the rapid, precise and non-destructive analysis of a wide range of organic materials has been comprehensively documented (Osborne et at., 1993). Most of the established methods have involved the development of NIRS calibrations for the quantitative prediction of composition in meat (Ben-Gera and Norris, 1968; Lanza, 1983; Clark and Short, 1994). This was a rational strategy to pursue during the initial stages of its application, given the type of equipment available, the state of development of the emerging discipline of chemometrics and the overwhelming commercial interest in solving such problems (Downey, 1994). One of the advantages of NIRS technology is not only to assess chemical structures through the analysis of the molecular bonds in the near infrared spectrum, but also to build an optical model characteristic of the sample which behaves like the “finger print” of the sample. This opens the possibility of using spectra to determine complex attributes of organic structures, which are related to molecular chromophores, organoleptic scores and sensory characteristics (Hildrum et al., 1994, 1995; Park et al., 1998). In addition, the application of statistical packages like principal component or discriminant analysis provides the possibility to understand the optical properties of the sample and make a classification without the chemical information. The objectives of this present work were: (1) to examine two methods of sample presentation to the instrument (intact and minced) and (2) to explore the use of principal component analysis (PCA) and Soft Independent Modelling of class Analogy (SIMCA) to classify muscles by quality attributes. Seventy-eight (n: 78) beef muscles (m. longissimus dorsi) from Hereford breed of cattle were used. The samples were scanned in a NIRS monochromator instrument (NIR Systems 6500, Silver Spring, MD, USA) in reflectance mode (log 1/R). Both intact and minced presentation to the instrument were explored. Qualitative analysis of optical information through PCA and SIMCA analysis showed differences in muscles resulting from two different feeding systems.

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Ecological flow calculations and evaluation techniques: Past, present, and future

  • LIU Yang;Wang Fang
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.28-28
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    • 2023
  • Most countries worldwide are finding it difficult to make decisions regarding the utilization of water resources and the ecological flow protection of rivers because of serious water shortages and global climate warming. To overcome this difficulty, accurate ecological flow processes and protected ecological objectives are required. Since the introduction of the concept, ecological flow calculations have been developed for more than 60 years. This technical development has always been dominated by countries such as the United States, Australia, and the United Kingdom. The technical applications, however, vary substantially worldwide. Some countries, for instance, did not readjust the method because of a lack of understanding of the ecological effect or because they failed to achieve elaborate scheduling. Mostly, readjustments were not made because the users could not make their choices from among numerous methods for ecological flow. This paper presents three research results based on a systematic review of 240 methods with clear connotation boundaries. First, the ecological flow algorithm was developed along with the scientific and technological progress in the river ecosystem theory, ecohydrological relationship, and characterization and simulation of hydrological and hydrodynamic processes. In addition, the basis of the method has evolved from the hydrological process of the ecosystem, hydraulics-habitat conditions, and social development interference to whole ecosystem simulation. Second, 240 methods were classified into 50 sub-categories to evaluate their advantages and disadvantages according to the ecological flow algorithms of hydrology, hydraulics, habitat, and other comprehensive methods. According to this evaluation, 60% of the methods were not suitable for further application, including the method based on the percentage of natural runoff. Furthermore, the applicability of the remaining methods was presented according to the evaluation based on the aspects of allocation of water resources, water conservancy project scheduling, and river ecological evaluation. Third, In the future, most developing countries should strengthen the guarantee of high-standard ecological flow via a coordination mechanism for the ecological flow guarantee established under a sustainable framework or via an ecological protection pattern at the national level according to the national system. Concurrently, a reliable ecological flow demand process should also be established on the basis of detailed investigation and research on the relationship between river habitats, ecological hydrology, and ecological hydraulics. This will ensure that the real-time evaluation of ecological flow forces the water conservancy project scheduling and accurate allocation of water.

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A Study of the Factors Affecting the Sustainability of Coastal Shipping Companies: from the Perspective of Safety (내항선사의 지속가능성에 미치는 영향 요인 연구 : 안전관련 중심으로)

  • Sung-Rae Cho;Chang-Kyun Noh
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.168-176
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    • 2023
  • The demand for measures to enhance the safety of maritime transportation is growing internationally, and coastal shipping companies are pursuing sustainability by establishing various maritime safety policies. Increased awareness of the safety management system and safety culture of coastal shipping companies will minimize accidents and increase corporate sustainability. This study empirically analyzed the impact of a safety management system (safety policy, risk management, and safety guarantee) on the corporate sustainability of coastal shipping companies through the mediation of safety culture. The survey questions for each variable were constructed based on previous research and a dministered to 204 employees of coastal shipping companies. Analysis founed that safety policy did not have a statistically significant effect on safety culture, but risk management and safety guarantees had a positive significant effect on safety culture, which in turn had a positive and significant effect on sustainability. Furthermore, we found that safety culture has a mediating effect on the relationship between risk management and safety guarantees and sustainability. Coastal shipping companies thus need to systematize and strengthen risk management and safety assurance to increase safety culture awareness, and increased safety culture awareness can also increase sustainability.

Interference-Prediction based Online Routing Aglorithm for MPLS Traffic Engineering (MPLS 트래픽 엔지니어링을 위한 간섭 예측 기반의 online 라우팅 알고리듬)

  • Lee, Dong-Hoon;Lee, Sung-Chang;Ye, Byung-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.12
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    • pp.9-16
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    • 2005
  • A new online routing algerian is proposed in this paper, which use the interference-prediction to solve the network congestion originated from extension of Internet scope and increasing amount of traffic. The end-to-end QoS has to be guaranteed in order to satisfy service level agreements (SLAs) in the integrated networks of next generation. For this purpose, bandwidth is allocated dynamically and effectively, moreover the path selection algorithm is required while considering the network performance. The proposed algorithm predicts the level of how much the amount of current demand interferes the future potential traffic, and then minimizes it. The proposed algorithm considers the bandwidth on demand, link state, and the information about ingress-egress pairs to maximize the network performance and to prevent the waste of the limited resources. In addition, the interference-prediction supports the bandwidth guarantee in dynamic network to accept more requests. In the result, the proposed algorithm performs the effective admission control and QoS routing. In this paper, we analyze the required conditions of routing algorithms, the aspect of recent research, and the representative algorithms to propose the optimized path selection algorithm adequate to Internet franc engineering. Based on these results, we analyze the problems of existing algorithms and propose our algorithm. The simulation shows improved performance by comparing with other algorithms and analyzing them.