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Study on the Feasibility of Space Weapon Development Utilizing Active Debris Removal Techniques and Understanding of Space Maneuver Warfare (우주 쓰레기 제거기술을 활용한 우주무기 개발 개연성 고찰 및 우주기동전(Space Maneuver Warfare)의 이해)

  • Seonghwan Choi
    • Journal of Space Technology and Applications
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    • v.3 no.2
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    • pp.165-198
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    • 2023
  • According to the studies recently published through advanced maui optical and space surveillance technologies (AMOS) Conference 2021, LEO conjunction assessment revolves around not on operating satellites but space debris such as rocket bodies and non-operational satellites, hence suggesting a solution through space traffic management. Against this backdrop, the issue of active debris removal (ADR) has emerged to the surface as an international challenge throughout the globe. In step with this, the United Nations General Assembly approved a resolution calling on nations to halt tests of direct-ascent anti-satellites, to which U.S. and twelve other nations included Republic of Korea were original signatories. ADR techniques are also actively being researched in the civil sector, and these commercial services, if successfully developed, could possibly be utilized for military use as well. As such, this paper will help readers' understanding for the current status of ADR techniques, space threat assessments, on-orbit rendezvous and proximity operations by looking at previous cases, reflecting on space-faring nations' ADR techniques and its development probability in relation to space weapons. As a conclusion, this study will propose the needs of developing space propulsion system by understanding Space Maneuver Warfare in preparation for the future space battlefield.

Factors influencing the axes of anterior teeth during SWA on masse sliding retraction with orthodontic mini-implant anchorage: a finite element study (교정용 미니 임플랜트 고정원과 SWA on masse sliding retraction 시 전치부 치축 조절 요인에 관한 유한요소해석)

  • Jeong, Hye-Sim;Moon, Yoon-Shik;Cho, Young-Soo;Lim, Seung-Min;Sung, Sang-Jin
    • The korean journal of orthodontics
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    • v.36 no.5
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    • pp.339-348
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    • 2006
  • Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted on masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased.4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

The Liability for Damage and Dispute Settlement Mechanism under the Space Law (우주법상 손해배상책임과 분쟁해결제도)

  • Lee, Kang-Bin
    • Journal of Arbitration Studies
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    • v.20 no.2
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    • pp.173-198
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    • 2010
  • The purpose of this paper is to research on the liability for the space damage and the settlement of the dispute with reference to the space activity under the international space treaty and national space law of Korea. The United Nations has adopted five treaties relating to the space activity as follows: The Outer Space Treaty of 1967, the Rescue and Return Agreement of 1968, the Liability Convention of 1972, the Registration Convention of 1974, and the Moon Treaty of 1979. All five treaties have come into force. Korea has ratified above four treaties except the Moon Treaty. Korea has enacted three national legislations relating to space development as follows: Aerospace Industry Development Promotion Act of 1987, Outer Space Development Promotion Act of 2005, Outer Space Damage Compensation Act of 2008. The Outer Space Treaty of 1967 regulates the international responsibility for national activities in outer space, the national tort liability for damage by space launching object, the national measures for dispute prevention and international consultation in the exploration and use of outer space, the joint resolution of practical questions by international inter-governmental organizations in the exploration and use of outer space. The Liability Convention of 1972 regulates the absolute liability by a launching state, the faulty liability by a launching state, the joint and several liability by a launching state, the person claiming for compensation, the claim method for compensation, the claim period of compensation, the claim for compensation and local remedy, the compensation amount for damage by a launching state, the establishment of the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea regulates the definition of space damage, the relation of the Outer Space Damage Compensation Act and the international treaty, the non-faulty liability for damage by a launching person, the concentration of liability and recourse by a launching person, the exclusion of application of the Product Liability Act, the limit amount of the liability for damage by a launching person, the cover of the liability insurance by a launching person, the measures and assistance by the government in case of occurring the space damage, the exercise period of the claim right of compensation for damage. The Liability Convention of 1972 should be improved as follows: the problem in respect of the claimer of compensation for damage, the problem in respect of the efficiency of decision by the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea should be improved as follows: the inclusion of indirect damage into the definition of space damage, the change of currency unit of the limit amount of liability for damage, the establishment of joint and several liability and recourse right for damage by space joint launching person, the establishment of the Space Damage Compensation Review Commission. The 1998 Final Draft Convention on the Settlement of Disputes Related to Space Activities of 1998 by ILA regulates the binding procedure and non-binding settlement procedure for the disputes in respect of space activity. The non-binding procedure regulates the negotiation or the peaceful means and compromise for dispute settlement. The binding procedure regulates the choice of a means among the following means: International Space Law Court if it will be established, International Court of Justice, and Arbitration Court. The above final Draft Convention by ILA will be a model for the innovative development in respect of the peaceful settlement of disputes with reference to space activity and will be useful for establishing the frame of practicable dispute settlement. Korea has built the space center at Oinarodo, Goheung Province in June 2009. Korea has launched the first small launch vehicle KSLV-1 at the Naro Space Center in August 2009 and June 2010. In Korea, it will be the possibility to be occurred the problems relating to the international responsibility and dispute settlement, and the liability for space damage in the course of space activity. Accordingly the Korean government and launching organization should make the legal and systematic policy to cope with such problems.

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A Study on the Promotion of Electronic Government and Plans for Archival Management (전자정부 추진과 기록관리방안)

  • Kim, Jae-hun
    • The Korean Journal of Archival Studies
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    • no.5
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    • pp.39-85
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    • 2002
  • This paper is aimed at proposing the policies for managing archives in the process of promoting Electronic Government System. Although there have been many studies of electronic government project and plans for its establishment, this research examines the electronic government system and its problems on the basis of archival science. What I acquired in this paper is as follows. The development of information technology needs great changes ranging from the nation to the individuals. It becomes common that the use of computerized program for business purposes, computerization of information materials and the effective way of search use of electronic documents. Therefore, more and more countries all over the world have been seeking to promote 'Electronic Government', which applies the fruits of the development in information technology to administration process. Recently, Korea has been rapidly entered into the 'Electronic Government' system being against the traditional way of administration. In electronic government system, the 'Life Cycle' of public records will be computerized. Therefore, it is important to change and develop along with the government's policies for 'electronic government project' in the archival management system. This means that the archival management system which have put emphasis on the textual records should be converted to electronic records system. In other words, the records management in electronic government system requires not the transfer and preservation of the records but the consistent management system including the whole process of creating, appraising, arranging, preserving and using the records. So, the systematic management of electronic records plays an important role in realization of electronic government, but it is a subject to be realized by electronic government at the same time. However, the government have overlooked the importance of archival management for long time, especially the importance of electronic records management system. First of all, this research attempts to infer limits and problems through the theoretical considerations of the existing studies for electronic government and to clear up the relations between electronic government and archival management. Based on this, I'll seek to progress the study through reviewing the present condition of archival management in the process of promoting electronic government and suggesting the policies for enhancing the successful electronic government and the construction of scientific archival management system. Since early 1990, many countries in the world have been making every effort to concrete 'Electronic Government'. Using the examples in other nations, it is not difficult to recognize that the embodiment of electronic government is closely connected with the archival management policies. Korea have completed legal and institutional equipments including the new establishment of "Electronic Government Law" to realize electronic government. Also, Korea has been promoting electronic government with the Ministry of Government Administration and Home Affairs and Government Computer Center as a leaders. Though managing records, especially the management of electronic records is essential in electronic government system, we haven't yet discussed this section in Korea. This is disapproved by the fact the Government Archives and Records Service has played little role in promoting electronic government project. There are two problems relating this environment. First, present system can't meet the consistent 'Life Cycle' ranging from the creation to the preservation of electronic records. Second, the 'Life Cycle' of electronic records is divided into two parts and managed separately by GCC and GARS. The life of records is not end with the process raged from creation to distribution. On the other hand, the records are approved their value only whole procedures. Therefore, GARS should play a deading role in designing and establishing the archival management system. The answer to these problems, is as follows. First, we have to complete the electronic records management system through introducing ERMS not EDMS. This means that we should not change and develop towards ERMS simply with supplementing the current electronic records management system. I confirm that it is important and proper to establish ERMS system from the very beginning of the process of promoting electronic government. Second, I suggest the developmental integration of GARS and GCC. At present, the divided operations of GCC and GARS, the former is in charge of the management center for electronic business and the latter is the hub institution of managing nation's records and archives result in many obstacles in establishing electronic government system and accomplishing the duties of systematic archival management. Therefore, I conclude that the expansive movement towards 'National Archives' through the integration among the related agencies will make a great contribution to the realization of electronic government and the establishment of archival management system. In addition to this, it will be of much help to constitute and operate the 'Task Force' regarding the management of electronic records with the two institution as the central figures.

The Effect of Surface Defects on the Cyclic Fatigue Fracture of HEROShaper Ni-Ti rotary files in a Dynamic Model: A Fractographic Analysis (Fractographic 분석을 통한 HEROShaper 니켈티타늄 전동 파일의 피로파절에 미치는 표면결함의 역할)

  • Lee, Jung-Kyu;Kim, Eui-Sung;Kang, Myoung-Whai;Kum, Kee-Yeon
    • Restorative Dentistry and Endodontics
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    • v.32 no.2
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    • pp.130-137
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    • 2007
  • This in vitro study examined the effect of surface defects on cutting blades on the extent of the cyclic fatigue fracture of HEROShaper Ni-Ti rotary files using fractographic analysis of the fractured surfaces. A total of 45 HEROShaper (MicroMega) Ni-Ti rotary flies with a #30/.04 taper were divided into three groups of 15 each. Group 1 contained new HEROShapers without any surface defects. Group 2 contained HEROShapers with manufacturing defects such as metal rollover and machining marks. Croup 3 contained HEROShapers that had been clinically used for the canal preparation of 4-6 molars A fatigue-testing device was designed to allow cyclic tension and compressive stress on the tip of the instrument whilst maintaining similar conditions to those experienced in a clinic. The level of fatigue fracture time was measured using a computer connected the system. Statistical analysis was performed using a Tukey's test. Scanning electron microscopy (SEM) was used for fractographic analysis of the fractured surfaces. The fatigue fracture time between groups 1 and 2, and between groups 1 and 3 was significantly different (p<0.05) but there was no significant difference between groups 2 and 3 (p>0.05). A low magnification SEM views show brittle fracture as the main initial failure mode At higher magnification, the brittle fracture region showed clusters of fatigue striations and a large number of secondary cracks. These fractures typically led to a central region of catastrophic ductile failure. Qualitatively, the ductile fracture region was characterized by the formation of microvoids and dimpling. The fractured surfaces of the HEROShapers in groups 2 and 3 were always associated with pre-existing surface defects. Typically, the fractured surface in the brittle fracture region showed evidence of cleavage (transgranular) facets across the grains, as well as intergranular facets along the grain boundaries. These results show that surface defects on cutting blades of Ni-Ti rotary files might be the preferred sites for the origin of fatigue fracture under experimental conditions. Furthermore this work demonstrates the utility of fractography in evaluating the failure of Ni-Ti rotary flies.

A Study on Collection and Usage of Panel Data on On-board Job Taking and Separation of Korean Seafarers (한국선원의 승선과 이직에 대한 패널자료 구축과 활용방안)

  • Park, Yong-An
    • Journal of Korea Port Economic Association
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    • v.32 no.4
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    • pp.149-163
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    • 2016
  • Seafarers are an essential resource in maritime industries, which provide navigation skills, vessel maneuvering skills and fishing skills in the fishery industry. They also work as a driving force in pilotage, port operation, vessel traffic service, and marine safety. Other areas in maritime services, which rely on seafarer include safety management of ships, supervisory activities, and maritime accident assessment. In these ways, Korean seafarers have contributed to the growth of Korean economy. However, there have been issues of high separation rate, shortage of supply, multi-nationality, multiplicity of culture caused by employment of foreign seafarers, and aging. The present paper finds that maritime officers and fishery officers demonstrate differences in the statistics of on-board job taking and separation: the separation rate of fishery officers is higher than that of maritime officers. The existing data and statistics by the Korea Seafarer's Welfare & Employment Center could be improved by changing its structure from time series to panel data. The Korea Seafarer's Welfare & Employment Center is the ideal institution for collecting the panel data, as it has already accumulated and published relevant statistics regarding seafarer. The basic design method of the panel data is to adopt and improve it by including the information on ratings of maritime and fishery industries, ranks in a ship, personal information, family life, and career goal. Panel data are useful in short- and long-term forecasts of supply of Korean seafarers; demand evaluation of education, training, and reeducation of the seafarers; demographical dynamic analysis on Korean seafarers; inducement policy of long-term on board job taking in harmony with man-power demands in marine industries such as pilotage service; implementation of job attractiveness policy on Korean seafarers; and employment stabilization of Korean seafarers.

Identification of Compound Heterozygous Alleles in a Patient with Autosomal Recessive Limb-Girdle Muscular Dystrophy (상염색체 열성 지대형 근이영양증 환자로부터 TTN 유전자의 복합 이형접합성 대립유전자의 분리)

  • Choi, Hee Ji;Lee, Soo Bin;Kwon, Hye Mi;Choi, Byung-Ok;Chung, Ki Wha
    • Journal of Life Science
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    • v.31 no.10
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    • pp.913-921
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    • 2021
  • Limb-girdle muscular dystrophy (LGMD) which is characterized by progressive muscle weakening of the hip and shoulder shows both dominant and recessive inheritances with many pathogenic genes including TTN. This study performed to identify genetic causes of a male patient with late onset (45 years old) autosomal recessive LGMD and atrial flutter. By application of the whole exome sequencing, we identified bi-allelic variants of TTN gene in the patient. One allele had a single missense variant of [c.24124G>T (p.V8042F)], while the other allele consisted of three missense variants of [c.29222G>C (p.R9741P) + c.67490A>G (p.H22497R) + c.75376C>T (p.R25126C)]. The p.V8042F allele was transmitted from his mother, while the other haplotype allele was putatively transmitted from his father. His two unaffected sons had only the p.R9741P. These variants have been not reported or rarely reported in the public human genome databases (1,000 Genome, gnomAD, and KRGDB). Most variants were located in the highly conserved immunoglobulin or fibronectin domains and were predicted to be pathogenic by the in silico analyses. The TTN giant protein plays a key role in muscle assembly, force transmission at the Z-line, and maintenance of resting tension in the I-band. In conclusion, we think that these bi-allelic compound heterozygous mutations may play a role as the genetic causes of the LGMD phenotype.

Characteristics of Astronomical Tide and Sea Level Fluctuations in Kiribati and Neighboring Countries (키리바시와 주변국 천문조위 특성 및 해수면 변동)

  • Kim, Yangoh;Kim, Jongkyu;Kim, Hyeon-Ju
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.5
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    • pp.746-752
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    • 2022
  • Kiribati, a South Pacific island, and its surrounding countries are gradually submerging to rising sea levels. The sea level continues to change according to the degree of thermal expansion of glaciers and seawater that decreases with increase in temperature. Global warming affects both the amount and volume of seawater, thus increasing sea level. Tidal phenomena occur twice a day to the attraction of celestial bodies such as the moon and the sun. The moon changes the angle of orbiting surface with the Earth equator every 18.6 years, and the magnitude of the tidal force changes depending on the distance between the Earth equator and the moon orbital surface. The University of Hawaii Sea Level Center selected Tarawa, Christmas, Kanton of Kiribati,, Lautoka, Suva of Fiji,Funafuti of Tuvalu, Nuk1u'alofa of Tonga, and Port Vila of Vanuatu. When comparing tide levels for each year for 19 years, the focus was on checking the change in sleep to Tide levels, and rising sea levels was the effect of Tide levels. The highest astronomical tides (HAT) and lowest astronomical tides (LAT) were identified as Tarawa 297.0, 50.8 cm, Christmas 123.8, 19.9 cm, Kanton 173.7, 39.9 cm, Lautoka 240.7, 11.3 cm, Funafuti 328.6, 98.4 cm, Nuk1u'alofa 188.8, 15.5 cm, Port Vila 161.5, -0.5cm, respectively. The Sea level rising speed was Tarawa 3.1 mm/year, Christmas -1.0 mm/year, Kanton 1.6 mm/year, Lautoka 3.1 mm/year, Suva 7.4 mm/year, Funafuti 1.4 mm/year, Nuk1u'alofa 4.2 mm/year, and Port Vila -1.2 mm/year, respectively

Prospects for development of cosmetic industry using natural products in Chungbuk (충북지역의 천연 자원을 활용한 화장품 산업의 발전 전망)

  • Hwang, Hyung seo
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.26-27
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    • 2018
  • With entry into force of the Nagoya Protocol to promote the fair sharing of the benefits of accessing and utilizing genetic resources, much support has been given to research on the development of biomaterials and products using domestic natural resources. Conservation and resource-saving of native species became very important through Nagoya Protocol enactment. The trend of cosmetic industry has been shifing from use synthetic chemicals to natural biomaterials, due to the safety regulations on new materials, ban on animal experiments, and expansion of cosmeceuticals range. In addition, functional cosmetic range has been expanded from whitening, wrinkle improvement, and ultraviolet shielding, to hair loss, hair loss alleviation, acne relaxation, and moisturizing of atopic skin, thus causing the activation of research about field of efficacy evaluation on natural biomaterials and commercialization. Chungbuk province is fostering the bio industry as a key industry for regional economic growth. For this purpose, Osong Biotechnology Complex/Ochang Science Industrial Complex in middle area, Jecheon biovalley in northern region, and Chungju Enterprise city have been established, thus playing a pivotal role in Bio innovative cluster in Korea. In particular, it was established the osong cosmetics clinical research support center to develop the cosmetics industry in chungbuk, thereby supporting clinical trials, efficacy evaluations, overseas certification, and overseas market entry in order to advance into the global market. In addition, oriental plants such as astragalus propinquus, schisandra chinensis, eucommia, alpiniae oxyphyllae fructus and biancaea sappan are being actively studied as global cosmetic ingredients through the promotion of various national research and development projects using natural materials in chungbuk province. The chungbuk natural product industry is expected to grow further throughout cosmetics industry development in the future, as companies and research institutes are actively promoting the secure index of effective material in natural products and effective material commercialization.

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Changes of in Vacuum Packed Pre-aged Venison with Seasoning during Chilled Storage (양념으로 사전 숙성하여 진공포장한 사슴고기의 냉장저장 중 품질 변화)

  • Kim Il-Suk;Jin Sang-Keun;Hah Kyung-Hee;Park Seok-Tae;Kwuak Kyung-Rak;Park Jung-Kwon;Kang Yang-Su;Chung Ku-Young
    • Food Science of Animal Resources
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    • v.25 no.4
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    • pp.442-448
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    • 2005
  • This study was carried out to evaluate the quality characteristics of the vacuum packed pre-aged venison with seasoning during chilled storage. The ham of deer were cut to cube and two seasonings such as red pepper sauce (T1) or soy sauce (T2) were seasoned by the proportions or meat to seasonings (1:1), respectively. The seasoned venison was aging by fill into plastic box at $0\pm1^{\circ}C$ for 10 days. And then, the aged meat from each pack was vacuum-packaged and stored at $0\pm1^{\circ}C$ for up to 28 days. pH were significantly decreased with storage periods in all treatments (p<0.05). Salinity $(\%)$ were no significant differences in T1 during the whole storage, but T2 had significantly high content $(1.33\%)$ at the storage days of 28 (p<0.05). Saccarinity $(\%)$ of T1 were significantly higher than that of T2 during the whole storage periods (p<0.05). As storage time extended the value of $L^*$ and $b^*$ in T1 were increased and those values decreased in T2. $a^*$ and shear force $(g/cm^2)$ or T1 and T2 were increased as the storage period passed In the result of sensory evaluation. all treatment had relatively high score $(T1\;6.75\~T2\;7.00)$ in overall acceptability during the storage period of 28 days. In conclusion, this study suggest that vacuum packed pre-aged venison with seasoning may be useful for new deer meat menu.