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Recent Advances on MOF-assisted Atmospheric Water Harvesting at Dry Regions (수분 수착 MOF를 이용한 건조한 지역의 대기 중 워터하베스팅 기술의 최근 동향)

  • Geunho Lee;Woochul Song
    • Membrane Journal
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    • v.34 no.1
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    • pp.30-37
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    • 2024
  • As a promising method to address global water scarcity, sorbent-assisted water harvesting from air has shown great potential to deliver drinking water for inlands lacking traditional water sources. In this article, the recent studies of using metal-organic frameworks (MOFs) as sorbents to harvest atmospheric water will be introduced. Compared to the other sorbent materials such as zeolites or silica-based materials, MOFs have shown prospective properties such as the water isotherm inflection points as low as ~10%, which are suitable for harvesting water at dry regions. Due to this property, recently, MOFs have been extensively adopted to develop practical water harvesting devices that can harvest water. Since atmospheric water is accessible anywhere and anytime in the world, this technology is expected to open a new avenue in terms of securing safe water for the future.

A Study on the Problems and Solutions of the Single-Person Navigation Duty System of Fishing Vessels (어선 1인 당직체계의 문제점과 해결방안에 관한 소고)

  • Chang-Hee, Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.30 no.1
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    • pp.89-96
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    • 2024
  • In many cases, fishing vessels operate on a schedule that leads to departure, sailing to the fishing spot, fishing, and sailing to the port of return. Consequently, most of the captains of fishing vessels operated on a single-person navigation duty system rarely have time to rest, resulting in frequent accidents owing to drowsy operation. In addition, accidents frequently occur when a tired captain leaves his duty to an unqualified seaman who does not have the basic knowledge of navigation and sleeps in the bedroom. This problem has been discussed for a long time; however, it has not been solved yet because of lack of proper countermeasures. As a measure to reduce these accidents, this article proposes a certification system for navigational-duty crew of fishing vessels.

A Study on Imposing Contribution in the Compensation for Uncontrollable Medical Malpractice during Delivery (분만관련 불가항력적 의료사고 보상제도에 있어 분담금부과에 관한 연구 -헌법재판소 2018. 4. 26. 선고 2015헌가13 사건을 중심으로-)

  • Beom, Kyung Chul
    • The Korean Society of Law and Medicine
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    • v.19 no.2
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    • pp.139-171
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    • 2018
  • The 「Act on Remedies for Injuries from Medical Malpractice and Mediation of Medical Disputes」(hereinafter referred to as 'the Act on Mediation of Medical Disputes') provides that the state should compensate the victims of medical accidents occurred irresistibly in childbirth despite that health and medical service personnel fulfilled their duty of care for their damage within the range of its budget(Article 46 of the Act on Mediation of Medical Disputes). Given that victims of medical accidents could expect demage recovery only through lawsuits thus far, this act can be said to be a groundbreaking act. However, However, as 30% of the costs for such medical accident compensation projects are borne by those who have records of childbirth among the founders of health and medical institutions (Article 21 of the Act on Mediation of Medical Disputes), there has been a question about whether doctors are held responsible despite that the accidents such as the deaths of mothers and newborn babies occurred irresistibly without doctors' fault. However, recently, the Constitutional Court ruled that 'the range of founders of health and medical institutions' and 'share ratios of finances for compensation' in Article 46 (3) of the Act on Mediation of Medical Disputes' related to the imposition of the share of costs are institutional (Constitutional Court ruling dated April 26, 2018, 2015Heonga13, hereinafter referred to as 'the ruling in the case'). Although the ruling in the case was made based on only the principle of statutory reservation and the principle of ban on comprehensive authorization, this paper added a practical judgment. This paper proved that the share of costs in this case has the nature of burden charges in pursuit of study and does not infringe on the property rights of the founders of health medical institutions even in light of the principle of proportionality because there is a legitimate reason for imposing the burden charge. The imposition of the share of costs in the system for compensation for medical accidents occurred irresistibly is against the principle of liability with fault in part. However, the medical accident compensation projects are rational a national policy for the victims of medical accidents and the medical world clearly gains some benefits from the effect to terminate medical disputes. The expansion of finances for compensation through the payments of the share of costs will reduce the suffering and misunderstanding of victims of medical accidents occurred in the process of childbirth and will be very helpful to the construction of stable treatment environments of medical workers by quickly establishing the medical accident compensation projects as such.

High Power Microwave Resonant Ring (고출력 마이크로파 Resonant Ring)

  • Park, S.S.;Park, S.W.;Kim, S.H.;Cho, M.H.;NamKung, W.
    • Proceedings of the KIEE Conference
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    • 1995.07c
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    • pp.1275-1277
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    • 1995
  • We designed and constructed an extremly high power s-band traveling wave resonator for the test of high power microwave components using 80MW pulsed klystron with $4{\mu}s$ pulse width. The 10dB directional coupler for the input power coupling was used, and the ring consists of phase shifter, tuner, H-band, and other microwave components. The designed total electrical length of the system is 10 times of the waveguide wavelength, ${\lambda}_g$=15.3cm, and the measured total insertion loss is 0.15dB. The low power test measurment showed the power multiplication of 14.69. The design goal is to achieve the peak power of 300MW, pulse width $4{\mu}s$ with 30 pulse repetition rate. In this article we discuss the treveling wave resonant ring constructed at the PAL laboratory together with the test results.

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A Study of Damage on the Pipe Flow Materials Caused by Solid Particle Erosion (고체입자 충돌침식으로 인한 배관 재질의 손상에 관한 연구)

  • Kim, Kyung-Hoon;Choi, Duk-Hyun;Kim, Hyung-Joon
    • Corrosion Science and Technology
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    • v.13 no.4
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    • pp.130-138
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    • 2014
  • Wall thinning can be classified into three types: flow-accelerated corrosion, cavitation erosion and solid particle erosion. This article presents a study of solid particle erosion, which frequently causes damages to power plants' pipe system. Unlike previous studies, this study uses a mechanism to make solid particles in a fluid flow collide with pipe materials in underwater condition. Experiment is conducted in three cases of velocity according to solid-water ratio using the three types of the materials of A106B, SS400, and A6061. The experiments were performed for 30 days, and the surface morphology and hardness of the materials were examined for every 7 days. Based on the velocity change of the solid particles in a fluid flow, the surface changes, the change in the amount of erosion, the erosion rate and the variation in the hardness of carbon steel and aluminum family pipe materials can all be determined. In addition, factor-based erosion rates are verified and a wall-thinning relation function is suggested for the pipe materials.

Nationalizing Transnationalism: A Comparative Study of the "Comfort Women" Social Movement in China, Taiwan, and South Korea

  • Alvarez, Maria del Pilar
    • Journal of Contemporary Eastern Asia
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    • v.19 no.1
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    • pp.8-30
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    • 2020
  • Most literature on the "comfort women" social movement focuses on the case of Korea. These works tend to transpose the meanings generated by South Korean organizations onto the transnational network, assuming certain homogeneity of repertoires and identities among the different social actors that comprise this network. Even though there is some degree of consensus about demands, repertoires, and advocacy strategies at the international level, does this same uniformity exist at the national level? In each country, what similarities and differences are present in the laboratories of ideas, relationships, and identities of social actors in the network? Symbolically and politically, do they challenge their respective societies in the same way? This article compares this social movement in South Korea, China, and Taiwan. My main argument is that the constitutive base for this transnational network is the domestic actions of these organizations. It is in the domestic sphere that these social actors reinforce their agendas, reinvent their repertoires, transform their identities, and expand their submerged networks, allowing national movements to retain their latency and autonomy. Following Melucci's relational approach to the study of social movements, this research is based on a qualitative analysis of institutional documents, participant observation, and open-ended interviews with members of the main social actors.

Types of Lexicographical Information Needs and their Relevance for Information Science

  • Bergenholtz, Henning;Agerbo, Heidi
    • Journal of Information Science Theory and Practice
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    • v.5 no.3
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    • pp.15-30
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    • 2017
  • In some situations, you need information in order to solve a problem that has occurred. In information science, user needs are often described through very specific examples rather than through a classification of situation types in which information needs occur. Furthermore, information science often describes general human needs, typically with a reference to Maslow's classification of needs (1954), instead of actual information needs. Lexicography has also focused on information needs, but has developed a more abstract classification of types of information needs, though (until more recent research into lexicographical functions) with a particular interest in linguistic uncertainties and the lack of knowledge and skills in relation to one or several languages. In this article, we suggest a classification of information needs in which a tripartition has been made according to the different types of situations: communicative needs, cognitive needs, and operative needs. This is a classification that is relevant and useful in general in our modern information society and therefore also relevant for information science, including lexicography.

Dynamic Modeling and Observer-based Servomechanism Control of a Towing Rope System

  • Tran, Anh Minh D.;Kim, Young Bok
    • Journal of Drive and Control
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    • v.13 no.4
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    • pp.23-30
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    • 2016
  • This paper presents a control-oriented dynamical model of a towing rope system with variable-length. In this system, a winch driven by a motor's torque uses the towing rope to pull a cart. In general, it is a difficult and complicated process to obtain an accurate mathematical model for this system. In particular, if the rope length is varied by operating the winch, the varying rope dynamics needs to be considered, and the key physical parameters need to be re-identified... However, real time parameter identification requires long computation time for the control scheme, and hence undesirable control performance. Therefore, in this article, the rope is modeled as a straight massless segment, with the mass of rope being considered partly with that of the cart, and partly as halfway to the winch. In addition, the changing spring constant and damping constant of the towing rope are accounted for as part of the dynamics of the winch. Finally, a reduced-order observer-based servomechanism controller is designed for the system, and the performance is evaluated by computer simulation.

A Study on the Energy Saving Methods of a House by Passive System (건축적 수법을 통한 주택의 에너지 절약 방안에 관한 연구)

  • 김용식
    • Journal of the Korean housing association
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    • v.13 no.2
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    • pp.73-78
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    • 2002
  • Recently, the energy consumption has been sharply increased and the environmental pollution has been serious, resulted in increased use of fossil fuel. These facts are applied to most fields, and are especially important issues in the field of architecture. The energy consumption rate of building is about 30% of all energy consumption, and the rate of residential is about 20% of the rate of building and is increasing gradually. The purpose of this article is firstly to analyse an actual energy consumption rate of model building and compare it with alternative methods, which are applied passive system to, and secondly to suggest an optimal passive method for saving energy. The conclusion of this study is as follows; 1) As compared with the existing house on actual energy consumption rate, 6% in changing orientation to a south, 9% in using double low-e glazing and 23% in shading is decreased. 2) The change of insulation from 50 to 100mm did not show dramatical difference in energy consumption rate. 3) As changed indoor temperature at 2$0^{\circ}C$ in winter and 27$^{\circ}C$ in summer, the rate shows a reduction of 14% compared with the existing condition.

Modified Sustained Natural Apophyseal Glides of Back Pain due to Combined Movement Dysfunction (복합운동 기능장애로 인한 요통의 수정된 SNAGs)

  • Park, Ji-Whan
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.8 no.1
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    • pp.25-30
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    • 2002
  • The main purpose of this article is to suggest a modified SNAGs manual method in based of Mulligan techniques. And this study aimed to resolve the back pain which has combined movement dysfunction in lumbar spine, in addition to upgrade of manual therapy technique in clinical field. The results of this study were as following; 1. The first introduction of SNAGs in Korea is the 'International Mulligan Concepts and Techniques Seminar' by Prof. Russell M. Woodman(Quinnipiac college, USA), 1998. SNAGs is defined a mobilization with movement manual therapy that facet joints of the lesion mobilized to anterior-superior direction according to the treatment plane in apophyseal joint of hypomobility. 2. A treatment mechanism of the SNAGs is, Mulligan say, HIVD which is the result of posterior disk bulging from a increased between intervertebral pressure due to hypo-mobile of facet joints in abnormal spine, so therapist should be necessary mobilization of zygophyseal joints especially in disk lesion. 3. Because Mulligan does not yet mentioned SNAGs techniques about a back pain with combined movements dysfunction, so we suggest a modified SNAGs method for manual therapy of back pain patients due to combined movement dysfunction at lumbar.

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