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Low beta superconducting cavity system design for HIAF iLinac

  • Mengxin Xu;Yuan He;Shengxue Zhang;Lubei Liu;Tiancai Jiang;Zehua Liang;Tong Liu;Yue Tao;Chunlong Li;Qitong Huang;Fengfeng Wang;Hao Guo;Feng Bai;Xianbo Xu;Shichun Huang;Xiaoli Li;Zhijun Wang;Shenghu Zhang;Jiancheng Yang;Evgeny Zaplatin
    • Nuclear Engineering and Technology
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    • v.55 no.7
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    • pp.2466-2473
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    • 2023
  • A superconducting ion-Linac (iLinac), which is supposed to work as the injector in the High Intensity heavy-ion Accelerator Facility project, is under development at the Institute of Modern Physics (IMP), Chinese Academy of Sciences. The iLinac is a superconducting heavy ion linear accelerator approximately 100 meters long and contains 96 superconducting cavities in two types of 17 cyromodules. Two types of superconducting resonators (quarter-wave resonators with a frequency of 81.25 MHz and an optimal beta β = v/c = 0.07 called QWR007 and half-wave resonators with a frequency of 162.5 MHz and an optimal beta β = 0.15 called HWR015) have been investigated. The cavity design included extensive multi-parameter electromagnetic simulations and mechanical analysis, and its results are described in details. The fundamental power coupler and cavity dynamic tuner designs are also presented in this article. The prototypes are under manufacturing and expected to be ready in 2023.

Intra-aneurysmatic thrombectomy in a distal anterior cerebral artery aneurysm

  • Juan Luis Gomez-Amador;Leoncio Alberto Tovar-Romero;Andrea Castillo-Matus;Ricardo Marian-Magana;Jorge Fernando Aragon-Arreola;Marcos Vinicius Sangrador-Deitos;Alan Hernandez-Hernandez;German Lopez-Valencia;Gerardo Yoshiaki Guinto-Nishimura;Jorge Rios-Zermeno
    • Journal of Cerebrovascular and Endovascular Neurosurgery
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    • v.25 no.4
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    • pp.462-467
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    • 2023
  • Thrombectomy procedures following intra-aneurysmatic lesions are extremely rare, and few cases have been reported. This article describes a microsurgical intra-aneurysmatic thrombectomy (MIaT) for a distal anterior cerebral artery (DACA) aneurysm. We present the case of a 48-year-old female that was admitted to the emergency room, showing neurologic deterioration with focal deficits. A computed tomography angiography (CTA) scan revealed an aneurysm located in the distal segment of the left anterior cerebral artery. During the surgical procedure, after clipping, a well-formed clot was visualized through the aneurysm's wall obstructing the left DACA flow. We proceeded to open the aneurysm's dome to remove the thrombus and clip the aneurysm neck, re-establishing the flow of the left DACA. Intra-aneurysmatic thrombosis can occur as a complication during clipping, obstructing the distal flow of vital arteries and causing fatal results in the patient's postoperative status. MIaT is a good technique for restoring the flow of the affected vessel and allows a secure aneurysm clipping after thrombus removal.

Choroid plexus arteriovenous malformations: A systematic review

  • Patricia Zhao;Georgios A. Maragkos;Kevin S. Livingstone;Kathryn N. Kearns;Min S. Park
    • Journal of Cerebrovascular and Endovascular Neurosurgery
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    • v.25 no.4
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    • pp.373-379
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    • 2023
  • To systematically review the reported outcomes and complications of different treatment options for choroid plexus arteriovenous malformations (AVMs), specifically focusing on surgical resection and endovascular embolization. A systematic literature review was performed using a PubMed query for studies published between January 1975 and July 2021. All studies describing the clinical presentation, management, and outcome of confirmed choroid plexus AVM cases were included. A total of 20 studies were included in the final analysis. Of these, 18 were single-patient case reports, one article contained two patients, and a single study was a cohort of 24 patients. Patient age ranged from one day to 61 years, with a mean of 31.8±20.4 years. Most choroid plexus AVMs were located in the lateral ventricles (14 patients, 70.0%), while there were four (20.0%) located in the third ventricle, and two in the fourth ventricle (10.0%). Almost all patients were treated with surgical resection (18 patients, 90%). In 14 patients (77.8%), complete resection of the AVM was achieved. A residual AVM was reported in one case (5.6%). Most patients were reported to have improved from their presentation status over time (14 patients, 70.0%). Presence or absence of long-term sequelae (e.g., neurologic deficits) were reported for 14 patients (70%). Eleven of these patients (78.6%) were reported to have no neurological sequelae. While data on choroid plexus AVMs remains limited, the available evidence suggests gross total resection of lesions in this location can be safely achieved with subsequent reduction in preoperative symptoms.

Space Development and Law in Asia (아시아의 우주개발과 우주법)

  • Cho, Hong-Je
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.349-384
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    • 2013
  • The Sputnik 1 launching in 1957 made the world recognize the necessity of international regulations on space development and activities in outer space. The United Nations established COPUOS the very next year, and adopted the mandate to examine legal issues concerning the peaceful uses of outer space. At the time, the military sector of the U.S.A. and the Soviet Union were in charge of the space development and they were not welcomed to discuss the prohibition of the military uses of outer space at the legal section in the COPUOS. Although both countries had common interests in securing the freedom of military uses in outer space. As the social and economic benefits derived from space activities have become more apparent, civil expenditures on space activities have continued to increase in several countries. Virtually all new spacefaring states explicitly place a priority on space-based applications to support social and economic development. Such space applications as satellite navigation and Earth imaging are core elements of almost every existing civil space program. Likewise, Moon exploration continues to be a priority for such established spacefaring states as China, Russia, India, and Japan. Recently, Companies that manufacture satellites and ground equipment have also seen significant growth. On 25 February 2012 China successfully launched the eleventh satellite for its indigenous global navigation and positioning satellite system, Beidou. Civil space activities began to grow in China when they were allocated to the China Great Wall Industry Corporation in 1986. China Aerospace Corporation was established in 1993, followed by the development of the China National Space Administration. In Japan civil space was initially coordinated by the National Space Activities Council formed in 1960. Most of the work was performed by the Institute of Space and Aeronautical Science of the University of Tokyo, the National Aerospace Laboratory, and, most importantly, the National Space Development Agency. In 2003 all this work was assumed by the Japanese Aerospace Exploration Agency(JAXA). Japan eases restrictions on military space development. On 20 June 2012 Japan passed the Partial Revision of the Cabinet Establishment Act, which restructured the authority to regulate Japanese space policy and budget, including the governance of the JAXA. Under this legislation, the Space Activities Commission of the Ministry of Education, Culture, Sports, Science, and Technology, which was responsible for the development of Japanese space program, will be abolished. Regulation of space policy and budget will be handed over to the Space Strategy Headquarter formed under the Prime Minister's Cabinet. Space Strategy will be supported by a Consultative Policy Commission as an academics and independent observers. By revoking Article 4 (Objectives of the Agency) of a law that previously governed JAXA and mandated the development of space programs for "peaceful purposes only," the new legislation demonstrates consistency with Article 2 of the 2008 Basic Space Law. In conformity with the principles laid down in the 1967 Outer Space Treaty JAXA is now free to pursue the non-aggressive military use of space. New legislation is the culmination of a decade-long process that sought ways to "leverage Japan's space development programs and technologies for security purposes, to bolster the nation's defenses in the face of increased tensions in East Asia." In this connection it would also be very important and necessary to create an Asian Space Agency(ASA) for strengthening cooperation within the Asian space community towards joint undertakings.

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Vietnam in 2017: The Situations and Prospects of Economics, Politics, and International Relations (베트남 2017: 경제, 정치, 대외관계의 현황과 전망)

  • CHAE, Su Hong;LEE, Han Woo
    • The Southeast Asian review
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    • v.28 no.1
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    • pp.21-51
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    • 2018
  • This article takes several approaches in explaining recent developments in Vietnam. First, it draws upon an array of sources that idealize Vietnam's embrace of capitalism and integration into the global market in order to sketch out its economy's progress in 2017. Second, it observes, evaluates, and diagnoses recent changes in the Vietnamese economy in the medium to long term by incorporating conflicting perspectives on Vietnam's performance as a capitalist country. Third, this article traces the power shifts that have risen from internal struggles in the Communist Party over political and social issues. Fourth, it elaborates on the aforementioned impact that foreign relations have had on socio-political developments in Vietnam, as well as the government's response. In so doing, it also attempts to evaluate, however briefly, the significance of the 25th anniversary of South Korea-Vietnam relations. Finally, it examines the public's reaction to the post-reform transitions in light of recent sociocultural changes. 2017 was a memorable year for Vietnam: a continuous march toward capitalism; the resulting expansion of the Vietnamese people's demands; political controversies and government control; the looming instability of United States-China relations and various attempts to address the situation. These events will inevitably replicate themselves in the future as the ostensibly socialist Vietnam adopts a capitalist model. The problem is that it is unclear whether these experiences will continue with the consent of the people of socialist Vietnam or engender resistance. It is difficult to achieve meaningful consent in the status quo of worsening inequalities, widespread corruption, monopoly on power, and sustained use of unskilled low-wage workers. In other words, when concerns such as welfare, public health, and the environment are set aside in favor of economic development and commercialization as they have been, discontent, rather than consent, will prevail. It is thus important to keep a watchful eye on the viability of the nominal economic growth, surface-level political stability, and strategic responses to foreign relations that took place in 2017.

Mobilities and Phenomenology of Place, A Perspective for the Popular Narrative Studies -David Seamon's Life Takes Place (모빌리티와 장소 현상학, 대중서사 연구의 한 관점 -데이비드 시먼의 『삶은 장소에서 일어난다』를 중심으로)

  • Kim, Tae-Hee
    • Journal of Popular Narrative
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    • v.25 no.4
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    • pp.469-506
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    • 2019
  • More than a few existing studies on popular narratives that pay attention to 'place' tend to adopt as their theoretical framework the celebrated distinction between space and place. According to this distinction, to put it simply, space is allegedly mobile, whereas place is static. Given this distinction, and in this age of high-mobility, where the spaces of mobilities seem to rapidly and extensively undermine the places of immobilities, would studies on popular narratives focusing on 'place' still remain convincing? Referring to David Seamon's recent book Life Takes Place: Phenomenology, Lifeworlds, and Place Making, this article aims to consider the possibility of studies on popular narratives in the era of high-mobility. To explore the concept of 'place' through phenomenological methodology, Seamon's book uses a theoretical framework called the 'progressive approximation,' which is attentive to synergistic relationality. According to this approach, the place should first be put under scrutiny as a whole, i.e. as the monad of place. Phenomenological studies on the monad of place as a whole identify places as the fundamental condition for human beings. Then, in accordance with the 'progressive' order of research, places are studied as dyads, i.e. as binary oppositions. Through these analyses, movement/rest, insideness/outsideness, the ordinary/the extra-ordinary, the within/the without, homeworld/alienworld are identified as the five dyads of place. To make a detour around these binary oppositions and confrontations, however, phenomenological studies on place now advance to the higher order of six place triads including place interaction, place identity, place release, place realization, place intensification, and place creation, whereby the study of place progressively approaches the 'approximate' essence of place. Reflectively asking himself about the idea of 'place' in the high-mobility era, the author of this informative and insightful book submits an answer that place is still the fundamental sine qua non of human beings. However, this answer is more likely to be bounded by the binary opposition of space/place, and movement/rest accordingly. In this article, I suggest as an alternative and hopefully more promising answer a perspective of transcending this kind of a dead-end dichotomy and of performing 'place-making' through the mobilities themselves, while presenting a noticeable example of the manner in which research on popular narratives could begin from this perspective.

A Study on Authentication Management and Communication Method using AKI Based Verification System in Smart Home Environment (스마트 홈 환경에서 AKI기반 검증 시스템을 활용한 인증관리 및 통신 기법에 관한 연구)

  • Jin, Byung Wook;Park, Jung Oh;Jun, Moon Seog
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.6
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    • pp.25-31
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    • 2016
  • With the development of IOT technology and the expansion of ICT services recently, a variety of home network services have been advanced based on wired and wireless high speed telecommunication. Domestic and global companies have been studying on the innovative technology for the users using IOT based technology and the environment for the smart home services has been gradually developed. The users live their lives with more convenience due to the expansions and developments of smart phones. However, the threatening on the security of the smart home network had occurred by various attacks with the connection to the smart environment telecommunication, lack of applications on low powered and light weight telecommunication, and the problems of security guideline. In addition, the solutions are required for the new and variant attacking cases such as data forgery and alteration of the device for disguising approach with ill will. In this article, the safe communication protocol was designed using certification management technique based on AKI which supplemented the weakness of PKI, the existing certification system in the smart environment. Utilizing the signature technique based on ECDSA, the efficiency on the communication performance was improved, and the security and the safety were analyzed on the security threat under the smart home environment.

Analysis of Articles Published in the Korean Journal of Oriental Medical Prescription (대한한의학방제학회지에 게재된 논문 동향 분석)

  • Kim, An-Na;Song, Mi-Young;Bae, Sun-Hee;Kim, Chul;Kim, Ha-Young;Kim, Young-Sik;Park, Kyoung-Bum;Kim, Hong-Jun
    • Herbal Formula Science
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    • v.18 no.1
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    • pp.57-77
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    • 2010
  • Objective : This study reviews the recent trend of oriental medical prescription research. The data examined are the articles published in the Korean Journal of Oriental Medical Prescription from 1990 to 2009. Method : The data are retrieved through the internet database Oriental Medicine Advanced Searching Integrated System (OASIS) and the collection of the Korean Journal of Oriental Medical Prescription. The number of articles examined is 385, published in 25 volumes of the journal. This study examines the nature of the articles, research methods, subjects, and author information. Research subjects are sorted out by the OASIS key words for the articles published before 1999, and by key word indexes cited in the abstracts for the articles published sinceafter. Results : Among the 385 articles collected, 206 are research articles, 143 philological articles, 35 case studies, and 1 special contribution. A majority of research articles are experimental studies (199 articles or 96.6%), while clinical reports (5 articles or 2.43%), and others studies (2 articles) occupy a small portion. Most of experimental studies (183 articles or 91%) examine the effectiveness of certain prescriptions or treatments. Among the effectiveness studies, 114 articles (62.3%) employ in vivo experiment design, 52 articles (28.42%) in vitro experiments, and 17 articles (9.29%) both in vivo and in vitro experiments. In terms of research subject, the most frequently indexed key words are hepatotoxicity among diseases (9 articles), Bojungikgitang (Bu-Zhong-Yi-Qi-Tang) among prescriptions (10 articles), Buja (Acontii Tuber) among meteria medica (4 articles), immunity and anti-oxidation among efficacy terminology (6 articles each), and Donguibogam(東醫寶鑑) among references in the key words (25 articles). Universities are the main affiliation of authors (76.42%), followed by university hospitals (6.71%), non-academic research institutes (5.55%), local clinics (4.67), academic research institutes (2.81%), hospitals (2.38%), and others (1.44%). The most affiliated institute of the first and correspondent authors is Wonkwang University. In terms of authorship, co-authorship outnumbers sole-authorship by 82.08% to 17.92%. The proportion of authors of a single article is 63.54% which is near the author productivity distribution described by Lotka's law.

Development of Oxo-biodegradable Bio-plastics Film Using Agricultural By-product such as Corn Husk, Soybean Husk, Rice Husk and Wheat Husk (농산부산물인 옥피, 대두피, 왕겨, 소맥피를 이용한 산화생분해 바이오플라스틱 필름 개발)

  • You, Young-Sun;Kim, Mi-Kyung;Park, Myung-Jong;Choi, Sung-Wook
    • Clean Technology
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    • v.20 no.3
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    • pp.205-211
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    • 2014
  • Biomass-based plastics containing the biomass content higher than 25 wt% have been considered as environment-friendly materials due to their effects on the reduction in the $CO_2$ emission and petroleum consumption as well as biodegradability after use. This article described the effect of the additions of oxo-biodegradable additive, 4 kinds of plant biomass, unsaturated fatty acid, citric acid in the properties of polyethylene films. Bio films were prepared using a variety of biomasses and tested for feasibility as a food packaging film. Mechanical properties such as tensile strength and percent elongation at break were evaluated. Husk biomasses from such as corn, soybean, rice, and wheat were pulverized using air classifying mill (ACM) and four different types of packaging films with thickness of $50{\mu}m$ were prepared using the pulverized biomass and low density polyethylene/linear low density polyethylene. The packaging film with wheat husk biomass was found to have greater mechanical properties of elongation and tensile strength than the other samples. Biodegradability of bio film was measured to be 51.5% compared to cellulose.

Fuel cell based CHP technologies for residential sector (연료전지와 마이크로 열병합 발전기술)

  • Son, Young Mok
    • Journal of Energy Engineering
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    • v.25 no.4
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    • pp.251-258
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    • 2016
  • This article reports current status of micro fuel cell-combined heat and power (${\mu}FC$-CHP) systems which utilize both power and heat generated by fuel cells. There are several options for constructing CHP systems and among them, fuel cells are the most useful and their total energy efficiency combining heat and power can reach up to about 90%. Fuel cells are classified as five types based on the electrolyte, but the most suitable fuel cell types for the ${\mu}FC$-CHP system are proton exchange membrane fuel cells (PEMFCs) and solid oxide fuel cells (SOFCs). ${\mu}FC$-CHP systems have several advantages such as decrease of the transmission-distribution loss, reduced costs of electricity due to distributed power generation, and environmental-friendliness owing to zero emission. The main drawback of the ${\mu}FC$-CHP systems is the high initial investment, however, it keeps decreasing as the technology development reduces production costs. Currently, Japan is the most leading country of the ${\mu}FC$-CHP market, however, Korea tries to expand the market by planning the deployment of 1 million units of ${\mu}FC$-CHP systems and governmental subsidiary supporting of half of the install price. In this report, integration technologies for connecting FC and CHP, and technology trends of leading countries are presented as well.