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Maritime Security of the Republic of Korea: year 1998 and year 2018 (한국의 해양안보: 1998년과 2018년)

  • Jung, Ho-Sub
    • Strategy21
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    • s.43
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    • pp.57-88
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    • 2018
  • Security situations are fundamentally and rapidly changing on the Korean Peninsula. Above all, as North Korea(NK) is heightening its nuclear and missile capabilities, Republic of Korea(ROK) is facing an existential threat. At the same time, as China's economic, diplomatic and military power is quickly rising, the balance of power is shifting and strategic competition between the Unite States(US) and China is accelerating in the Asia-Pacific region. Under the pressure of development of these situations, ROK seems to face allegedly the most serious crisis in its national security since the end of the Korean War. In the current grim geopolitical situation, maritime security may become the most difficult security challenge for ROK in the years to come. The purpose of this paper is to compare major changes in maritime security affairs of the ROK during last twenty years from 1998 until now(2018). 1998 was when this journal 『Strategy 21』 was published for the first time by the Korea Institute for Maritime Strategy. Then, this paper tries to identify challenges and risks with which this country has to deal for its survival and prosperity, and to propose some recommendations for the government, the Navy, and the Coast Guard as they are responsible for the maritime security of the country. The recommendations of this paper are as follows: strengthen ROK-US alliance and expand security cooperation with regional powers in support of the maintenance of the current security order in the region; building-up of maritime security capacity in preparation for crisis on the maritime domain with the navy targeting to acquire 'a non-nuclear, balance-of-terror capability, to improve interoperability with the Coast Guard based on 'a national fleet,' and to actively pursue innovation in naval science and technology. Finally, this paper proposes that naval capability the country needs in another twenty years depends on how effectively and rigorously the navy put its utmost efforts towards building 'a strongest navy' today.

Efficiency of catalyst-coated ceramic filter with acid treatment (촉매담지 세라믹 필터의 표면 산처리 효과)

  • Cho, Eul-Hoon;Suh, Kwang-Suck;Kim, Su-Hyo;Shin, Min-Chul;Shin, Byeong-Kil;Kim, Jin-Seong;Lee, Hee-Soo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.18 no.2
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    • pp.91-95
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    • 2008
  • Ceramic filter was prepared using cordierite powder and it was coated with $V_2O_5$ catalyst by vacuum impregnation method. The filter had the apparent porosity of 58 %, the compressive strength of 10 MPa and the pressure drop of 1200 Pa at the face velocity of 5 cm/see and 400$^{\circ}C$. $NO_x$ removal efficiency of only $V_2O_5$ coated on cordierite filter showed the removal efficiency of 80 %, and it was improved up to 90 % by increasing specific surface area of filter elements from the acid treatment. The high surface area is due to the removal of Mg and Al ions from the silicate structure and subsequent generation of free amorphous silicate on the surface of the cordierite.

Collection Performance of an Electret Cabin Air Filter for Fine Particles (승용차용 정전 필터의 미세 입자 포집 특성)

  • Ji, Jun-Ho;Gang, Seok-Hun;Kim, Dong-Cheol;Hwang, Jeong-Ho;Yun, Ung-Seop;Bae, Gwi-Nam
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.11
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    • pp.1650-1658
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    • 2001
  • An electret filter is composed of permanently charged electret fibers and is widely used in applications requiring high collection efficiency and low-pressure drop. In this work, the fractional collection efficiency of the filter media used in manufacturing cabin air filters was investigated by using highly monodisperse particles ranging from 0.02 to 0.6 $\mu\textrm{m}$ in diameter at three different charging states: singly charged, uncharged, and equilibrium charged. The face velocity was varied from 2.4 to 20.4 crus. It was fecund that the fractional efficiency curve fur singly charged particles shows a typical trend that the collection efficiency is minimum at about 0.3 $\mu\textrm{m}$ in diameter. The fractional efficiency of equilibrium charged particles were not severely varied with the particle diameter. The collection efficiency curve fur uncharged particles has a minimum near 0.1 $\mu\textrm{m}$ in diameter. Another experiment was conducted for a cartridge filter to examine the effect of charge depletion on the collection efficiency in a cabin air filter. The result shows that the charge depletion of the cartridge filter can significantly lower the collection efficiency.

An Analysis of Management Methods for Traditional Village in Japan -The Case of Tumago Village and Shiragawa Village- (일본 전통마을의 유지.관리방법 분석 -쯔마고마을과 시라카와마을을 사례로-)

  • 강동진
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.4
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    • pp.91-104
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    • 2000
  • The traditional village, which is subject for this paper, can be defined as a community having unique combinations of natural, cultural, and social characteristics of that nation, which reflects settlement environments during hundreds of years. Now, in spite of tis potential power of traditional village, national strategies do not find satifsactory directions in Korea. In terms of this concenrs, this paper tries to analyze and diagnose about successful precedents(Tsumage village and Shiragawa village, Japan) with focus on the village management. And this paper aims to explore concrete management systems of Japanese cases, to find clues for practical application, and to suggest several instructive concepts in the light of management system of traditional village management. The analysis is progressed in three viewpoints(village space, village attraction, and village community). And it is extracted that diverse management systems are necessary to secure sustainable traditional village and their way of life, particularly in the face of the pressure of tourism. As a result of exploring of Japanese two cases, representative characteristics, which are found, are as follow; Fist, objective of management is not tourism development but maintenance of sustainable life system. Second, management systems are having not compulsory but spontaneous open decision making process, and in particular, village management is mainly operated by the local government and semipublic institute(inhabitants-oriented0 which have the strongest influential power in village composition units. Finally, village management programs are mostly experience-type and are composed of public law and regulations, diverse operation program, and individual efforts of inhabitants for village management. Because this paper mainly focused on two precedents, there should be more diverse cases. however, extracted conclusions have practical meanings for village management and can be used in re-establishing management concepts of Korean traditional villages.

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A Sunglasses Design to Prevent Snow Blindness at High Altitude (설맹 방지를 위한 고소등반용 선글라스 디자인)

  • Choi, Byung-Jin;Jang, Joon-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.4
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    • pp.19-22
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    • 2007
  • Recently, the population of people exploring High Mountain trekking or expedition is increasing as an increase in the backpackers. Many accidents occurring at High Mountain above 6,000 m are the results of snow blindness. The damage of cornea and/or retina is direct cause of snow blindness. The UV intensity increases on the hand, along with the altitude caused by decrease in the atmospheric pressure, on the other hand the reflections by bright snow at high mountain area. And it increases approximately 3 times and 4 times higher than the ground level at altitude of 4,000 m and 8,000 m, respectively. The use of sunglasses is more favorable than goggles for the protection of snow blindness at High Mountains. The eye frames that have high mechanical strength and the plastic lenses which can protect UV 100% are recommended. The attachable shielding pads are needed to prevent the incident UV light reflected or scattered from the gap between glasses frame and face. The sunglasses must have flexible and long temples to wind the ears adequately for the prevention of detachment during climbing and it is recommended that the metal frame to be coated with plastics to prevent the eye surroundings from frostbite.

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Simultaneous Removal of NOx/SOx by Catalyst-loaded Cordierite Porous Filter (촉매 담지 코디어라이트 다공성 필터의 NOx/SOx 동시제거에 대한 연구)

  • Lee, Shi-Hee;Chung, Koo-Chun;Kim, Jee-Woong;Shin, Min-Chul;Lee, Hee-Soo
    • Analytical Science and Technology
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    • v.15 no.3
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    • pp.256-262
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    • 2002
  • After porous filters were manufactured using cordierite powder whose mean paricle size was 200${\mu}m$, they were loaded with catalysts such as $V_2O_5$, CuO and $LaCoO_3$ by vacuum impregnation method. And the NOx/SOx simultaneous removal efficiency was measured by passing NO and $SO_2$ through catalyst-loaded ceramic filters. The cordierite porous filters had the apparent porosity of 61.6%, the compressive strength of 12.3 MPa and the pressure drop of 147 pa at the face velocity of 5 cm/sec. According to the analysis of NO/$SO_2$ simultaneous removal efficiency, perovskite $LaCoO_3$ catalyst was the most efficient for the simultaneous NO and $SO_2$ removal. The $LaCoO_3$ catalyst-loaded filter could remove more than 90% for NO and more than 80% for $SO_2$.

Treatment of Lymphangioma combined with Facial Bone Deformity (안면골 변형을 동반한 림프관종의 치험례)

  • Cha Sang-Myun;Choi Hee-Youn
    • Korean Journal of Head & Neck Oncology
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    • v.7 no.1
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    • pp.24-34
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    • 1991
  • Lymphangioma is a benign, growth of lymphatic tissue that is present at birth or develops in early childhood, which may cause serious alterations in growth and developmemt. The problems with facial lymphangioma is usually releated directly to their size and to the area of the face which is involved. The lesions themselves may range from small, localized blemishes to huge facial masses involving both soft tissue and underlying bone and causing great distortion and asymmetry. The facial bones are seldom involved, but the natutal evolution of an individual lesion often cannot be accurately predicted when the child is first seen. Any changes in the underlying facial bone could be due either to a direct growth of the lesion into the bone, or secondary to pressure of the lesion growing outside the bone itself. A case of cystic lymphangioma extending from the neck to the tongue is reported. A six-year-old female was admitted because of swelling of the tongue. At that time, the tongue reportedly reached the extraoral size of 7x5x2.5cm and a soft, diffuse swelling of left anterior neck was revealed. The removal of cystic mass including left neck dissection and partial glossectomy were undertaken. The another case of lymphangioma is located on mandibular cheek. A twenty nine-year-old male was admitted because of palpable mass of the left mandibular area and fissure of palate. The radical excision of mass with mandibulectomy of body were undertuken. Thus we reported such a rare case and reviewed the lymphangioma.

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Factors Related to Job Retention of Physicians in Public Hospitals (국공립병원 의사의 근무지속의사 관련 요인)

  • Oh, Moo-Kyung;Kwon, Yong-Jin;Lee, HeyJean;Lee, Jin-Seok
    • Health Policy and Management
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    • v.22 no.3
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    • pp.365-382
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    • 2012
  • Background : Public hospitals suffer worsening shortage of physicians and face great pressure of recruiting doctors. This study is aim to identify the factors associated with retention of physicians who are working in public hospitals. Methods : We conducted a cross-sectional and self-administered questionnaire survey in July, 2011. A total of 333 physicians responded from the 31 public hospitals. We analyzed the difference of job retention across the variables among doctors stratified as salaried and public health doctors. We used chi-square test and multiple logistic regression analysis. Results : To the salaried doctor, longer work period(OR=2.04 in 3rd quartile), professional autonomy(OR=2.69), and positive attitude toward public health(OR=2.39) affect to the higher job retention whereas complain of low income(OR=0.33) and complain of poor clinical environment(OR=0.26) affects to the lower job retention. To the public health doctors, community connections such as hometown(OR=6.27), spouse factors(OR=3.49), and positive attitude toward public health(OR=3.19) affect to the higher job retention. But longer work period(OR=0.17 in 3rd quartile) affects to the lower job retention. Conclusions : Associated factors of job retention vary across physician's status. Professional autonomy has major impact on the job retention to the salaried doctor. And familial factors as well as community relationship have greatest impact to the public health doctor. Positive attitude toward public health is associated with the higher job retention to the both of salaried and public health doctors.

Evaluation of Exposure to Isocyanates Used in Furniture Industry (가구산업에 사용되는 이소시안화물 폭로에 대한 평가)

  • Lee, Su-Gil;Lee, Nae-Woo;Pisaniello, Dino. L
    • Journal of the Korean Society of Safety
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    • v.21 no.2 s.74
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    • pp.138-142
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    • 2006
  • Occupational asthma is commonly known to be induced by isocyanate exposure. Spray painters generally use isocyanates for 2-pack spray painting to coat wooden panel surfaces in the furniture industry in South Australia. Due to a lack of actual exposure data, this study conducted environmental and dermal/ocular monitoring from a company in the furniture industry. According to this study, there was no significant airborne contamination, due to the use of high volume low pressure (HVLP) spray guns, low concentration of hardener in paint solutions and appropriate respirator like full face-air line respirator. There was no significant HDI detection in the general work area around the spray booths. Owing to the use of disposable nitrile gloves during the spray painting, no significant dermal exposure was found. According to color monitoring, there was a possible dermal exposure from surfaces in the workplace, unless either protective gloves were worn or appropriate working practices like clean-up process and storage in a secure places. No eye contamination was detected from the spray painters. No significant exposure levels from inhalational, dermal, ocular were found. The area of most concern was work practices.

Numerical Modeling of Storm Surge around the Coast of Pusan (부산연안 폭풍해일 변동양상과 수치예측)

  • 이종섭;주귀홍;장선덕
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.2 no.2
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    • pp.104-111
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    • 1990
  • The water level variation due to the Typhoon around the coast of Pusan in the southern sea of Korea is investigated from the observed tidal record. Water level variations at six stations along the coast are discussed in association with the meteorological data. The characteristics of storm surge at Pusan during Typhoon Thelma in 1987 is analysed using the observed data, and it is performed the numerical simulation of storm surge which includes a inverse barometric effect due to the horizontal distribution of sea sur-face pressure. From the calculation results, the peak value of storm surge in the coast of Pusan was occur-red around the 01:00 July 16th, which is well coincident with the observed water level variation at the Kadukdo. However, the calculated value at the Pusan TBM is inconsistent with the observed one, which is regarded due to a reason that the Tidal Bench Mark (TBM) locates in the channel. In the computation results, the maximum surge occurs at the coast of Nakdong estuary, which is considered primarily due to a topographic effect, and water level variation exceeded 2.5 meter in these areas while only about 60 cm in another coasts.

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