• 정보처리학회논문지C
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• 제13C권7호
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• pp.913-922
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• 2006

주파수공용통신(TRS: Trunked Radio Service)이란 무선통신을 하는 사람이 특정한 주파수를 이용하던 종래의 무선통신방식과는 달리 중계소에 할당된 소수의 주파수를 다수의 이용자가 공동으로 사용하는 방식을 말한다. TRS 시스템의 가장 큰 특징은 일대 다수의 그룹 및 지령 통신방식이다. TRS 시스템의 구성은 여러 개의 그룹으로 구성되며, 각 그룹은 업무내용에 관련된 유사한 목적을 가진 사용자들의 단말기로 구성된다. 위와 같은 여러 목적에 따라 다양한 형태의 연결이나 그룹 통신이 이뤄질 경우, 여러 가지 형태의 공격에 노출될 수 있으며, 대규모 통신을 위한 키 분배 혹은 설정에 많은 문제점을 가질 수 있다. 본고에서는 TRS 상에서 안전한.통신을 수행하는데 있어 필수 요소인 그룹 키 분배방식을 고찰하며, 통신 횟수를 줄이면서도 참여자 인증을 수행할 수 있는 효율적인 그룹 키 분배 방식을 제안하였다.

• 자원환경지질
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• 제24권3호
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• pp.261-276
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• 1991

The main aspect of this study are to clarify igneous activity of igneous rocks, which is a member of various intrusives and volcanics exposed in Naju-Namchang area of southern central zone of Ogcheon Geosynclinal Belt, southern part of Youngdong-Kwangju depression zone of tectonic provinces in Korea. Naju-Namchang area are subdivided into three rock belts based on occuring of Cretaceous granites. Three rock belts consist of foliated granites, Jurassic granites and Cretaceous granites in central granitic rock belt (C-C), and acidic tuff and lavas in northwest volcanic rock belt(C-NW) and southeast volcanic rock belt(C-SE). Chemical composition of these igneous rocks show mostly similar trend to the Daly's values on Harker diagram and correspond to VAG + Syn-COLG region on Pearce's discrimination diagram. These igneous rocks vary wide range in total REE amount(37.4-221.3ppm) characterized by enriched LREE content and steep negative slope in Eu(-) anomaly. It is concluded each synchronous granites which composed of serveral rock facies is considered to formed by differentiation of co-magma at continental margin, and igneous activity of study area are two more Pre-Cambrian Orogenies, Songrim Disturbance, Daebo Orogeny and Bulkuksa Disturbance.

• 농촌계획
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• 제20권4호
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• pp.145-155
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• 2014

Since greenhouse gas emissions increase continuously, the authorities have needed climate change countermeasure for adapting the acceleration of climate change damages. According to "Framework Act on Low Carbon, Green Growth", Korean local governments should have established the implementation plan of climate change adaptation. These guidelines which is the implementation plan of climate change adaptation should be established countermeasure in 7 fields such as Health, Digester/Catastrophe, Agriculture, Forest, Ecosystem, Water Management and Marine/Fisheries. Basically the Korean local governments expose vulnerable financial condition, therefore the authorities might be assessed the vulnerability by local regions and fields, in order to establish an efficient implementation plan of climate change adaptation. Based on this concepts, this research used 3 methods which are LCCGIS, questionnaire survey analysis and analysis of existing data for the multiphasic vulnerable assessment. This study was verified the correlation among 7 elements of climate change vulnerability by 3 analysis methods, in order to respond climate change vulnerability in rural areas, Seocheon-gun. If the regions were evaluated as a vulnerable area by two or more evaluation methods in the results of 3 methods' comparison and evaluation, those areas were selected by vulnerable area. As a result, the vulnerable area of heavy rain and flood was Janghang-eup and Maseo-myeon, the vulnerable area of typhoon was Janghang-eup, Masan-myeon and Seo-myeon. 3 regions (i.e. Janghang-eup, Biin-myeon, Seo-myeon) were vulnerable to coastal flooding, moreover Masan-myeon, Pangyo-myeon and Biin-myeon exposed to vulnerability of landslide. In addition, Pangyo-myeon, Biin-myeon and Masan-myeon was evaluated vulnerable to forest fire, as well as the 3 sites; Masan-myeon, Masan-myeon and Pangyo-myeon was identified vulnerable to ecosystem. Lastly, 3 regions (i.e. Janghang-eup, Masan-myeon and Masan-myeon) showed vulnerable to flood control, additionally Janghang-eup and Seo-myeon was vulnerable to water supply. However, all region was evaluated vulnerable to water quality separately. In a nutshell this paper aims at deriving regions which expose climate change vulnerabilities by multiphasic vulnerable assessment of climate change, and comparing-evaluating the assessments.

• Archives of Plastic Surgery
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• 제34권4호
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• pp.485-489
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• 2007

Purpose: The basic vascular anatomy and versatility of the anterolateral thigh flap was reported firstly by Song in 1984 and then by Zhang who introduced the reverse flow pattern of this flap. In this case, the authors reviewed various articles and their experiences with the distally based anterolateral thigh flap and applied it for coverage of bone-exposed wound occurred at the distal of the disarticulated knee stump. We consequently reported the reliability and resourcefulness of this flap in the difficult and limited situation. Methods: A 67-year-old-man who had suffered from arteriosclerotic obliterans inevitably underwent the disarticulation at knee joint due to clinical deterioration. He presented to our clinic with soft tissue necrosis and bone exposure at the stump. We debrided the wound and conducted the distally based anterolateral thigh island flap by transecting proximal portion of descending branch of the lateral circumflex femoral artery and the $14{\times}10cm$ sized flap was transferred to cover the defect. The pedicle measured 14 cm in length with pivot point 7 cm above the patella. Results: The postoperative course was mainly uneventful except early venous congestion for 4 days and subsequent partial skin loss. The wound was healed by secondary intension and no other sequelae had been observed during follow-up period of 12 months. Conclusion: Despite the presence of various reconstructive choices, the distally based anterolateral thigh island flap can be designed to repair soft tissue defects around the knee region, providing its reliable blood supply and long pedicle length, especially in the challenging cases.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.54-54
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• 2010

Zinc oxide is metal oxide semiconductor with the 3.37 eV bandgap energy. Zinc oxide is very attractive materials for many application fields. Zinc Oxide has many advantages such as high conductivity and good transmittance in visible region. Also it is cheaper than other semiconductor materials such as indium tin oxide (ITO). Therefore, ZnO is alternative material for ITO. ZnO is attracting attention for its application to transparent conductive oxide (TCO) films, surface acoustic wave (SAW), films bulk acoustic resonator (FBAR), piezoelectric materials, gas-sensing, solar cells and photocatalyst. In this study, we synthesized ZnO nanoparticles and defined their physical and chemical properties. Also we studied about the application of ZnO nanoparticles as a photocatalyst and try to find a enhancement photocatalytic activity of ZnO nanorticles.. We synthesized ZnO nanoparticles using spray-pyrolysis method and defined the physical and optical properties of ZnO nanoparticles in experiment I. When the ZnO are exposed to UV light, reduction and oxidation(REDOX) reaction will occur on the ZnO surface and generate ${O_2}^-$ and OH radicals. These powerful oxidizing agents are proven to be effective in decomposition of the harmful organic materials and convert them into $CO_2$ and $H_2O$. Therefore, we investigated that the photocatalytic activity was increased through the surface modification of synthesized ZnO nanoparticles. In experiment II, we studied on the stability of ZnO nanoparticles in water. It is well known that ZnO is unstable in water in comparison with $TiO_2$. $Zn(OH)_2$ was formed at the ZnO surface and ZnO become inactive as a photocatalyst when ZnO is present in the solution. Therefore, we prepared synthesized ZnO nanoparticles that were immersed in the water and dried in the oven. After that, we measured photocatalytic activities of prepared samples and find the cause of their photocatalytic activity changes.

• 대한수의학회지
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• 제11권1호
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• pp.59-63
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• 1971

Current interest in ${\gamma}$-aminobutyric acid (GABA) has arisen from the convergence of several independent line of investigation leading to the demonstration that this and related substances are normal products of brain metabolism and that GABA has an important physiological action upon brain function as well as upon certain peripheral nervous structures. The interest for neurophysiologists has been enhanced by the importance of the discovery for the role of humoral mediator of synaptic transmission or regulator of neuronal activity in the central nervous system, particularly if it may shed some elight upon the nature of central inhibitory processes. In accordance with such an interest and importance, this work was performed in order to standardize the normal content as a preliminary investigation of so-called night active and daytime active animals GABA content in their brains when they are exposed to light and darkness. The method, through which the estimation has made in this work, was paper chromatographic method developed by Maynert and Klingman for the estimation of GABA content in animal tissues. The results obtained are summerized as follows: 1) GABA content in the cerebral cortex of house rat ranged from 90 to $310{\mu}g/gm$ of wet weight. 2) The content of GAGA ranging from 130 to $510{\mu}g/gm$ of wet weight was occurred from midbrain of the rat. 3) GABA content was ranged from 30 to $150 {\mu}g/gm$ of wet weight of the rat cerebellum. 4) The contents of fowl cerebral cortex, midbrain, and cerebellum are estimated as ranging 230-590, 250-620, $50-280{\mu}g/gm$ of wet weight, respectively. As a result, it may be concluded that among three brain tissues of both animals the midbrain is the highest region in GABA content. Fowl brain, on the other side, contains more higher GABA content than the house rat brain does.

• 한국구조물진단유지관리공학회 논문집
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• 제14권1호
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• pp.141-147
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• 2010

일반적으로 일반대기중의 $CO_2$ 농도는 낮기 때문에 자연상태에서는 중성화정도는 매우 느리게 된다. 따라서 콘크리트의 중성화 정도를 평가하기 위해서는 일반적으로 진행속도를 빠르게 하기 위하여 촉진 시험조건하에서 진행하게 된다. 따라서 본 논문은 $CO_2$의 확산 및 $Ca(OH)_2$와의 반응을 바탕으로 한 수학적 모델을 통하여 일반대기환경하에서의 콘크리트 중성화 진행을 예측하고자 한다. 이를 위하여 본 논문에서는 촉진 중성화시험을 통하여 얻어진 실험치와 가장 유사한 $CO_2$ 확산계수를 채택하여 일반대기환경에서의 중성화진행을 예측하고자 하였다. 그 결과 $CO_2$ 확산계수를 이용한 수학적 모델을 통하여 마감재 종류에 관계없이 일반대기환경에서의 콘크리트 중성화진행속도를 예측할 수 있었다.

• 농업생명과학연구
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• 제45권2호
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• pp.1-7
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• 2011

본 연구는 중부지방에서 동절기간에 적용 가능한 상록지피식물의 이용을 확대하기 위하여 서로 다른 광조건에서의 생장변화를 조사하였다. Nandina domestica는 동절기 동안 광조건에 관계없이 음지에서 높은 엽록소값을 나타냈다. 이후 4월에는 서울의 반포지역에서 엽록소 값이 광조건에 따른 차이는 나타나지 않았으나 북풍에 노출되어 있는 과천지역에서는 양지에서 현저히 감소하였으며 잎이 모두 낙엽 되었다. Ophiopogon japonicus는 지역에 관계없이 2월에 양지보다 음지에서 엽록소값이 두 배 이상의 높은 값을 나타냈으며 L과 b값도 조사기간 동안 음지조건에서 높게 나타났다. 4월에는 반포지역에서 광조건에 따른 차이가 없었으나 과천지역에서는 양지에서 동절기 동안 엽색이 탈색되었다. Pachysandra terminalis는 조사지역과 기간에 관계없이 음지조건에서 엽록소값과 L, b값이 높게 나타났다. 따라서 중부지방에서 상록지피식물을 이용하기 위해서는 음지조건의 조성이 필요할 것으로 여겨진다.

• 대한두개안면성형외과학회지
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• 제20권5호
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• pp.304-309
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• 2019

Background: Treatment for venous malformations of the head and neck includes sclerotherapy, surgical resection, or a combination of both. Surgical resection can remove or reduce the volume of vascular lesions; however, surgery can cause postoperative scarring and potential surgical complications. This study sought to determine the effectiveness of surgery for the treatment of venous malformations of the head and neck. Methods: A retrospective review of the medical records of patients who received surgeries for venous malformations of the head and neck from January 2011 to July 2019 was performed. Using clinical photographs, preoperative and postoperative Doppler ultrasonography, outpatient clinic records, and operation records, the postoperative result and complications were evaluated for each case. Results: Among patients who visited our vascular anomalies clinic, 43 patients (ratio of male to female= 24:19) received surgeries for venous malformations of the head and neck. Twenty-nine patients had undergone surgery only, five patients received sclerotherapy after surgery, and nine patients received surgery after preoperative sclerotherapy. In postoperative evaluations, the result was excellent in 24 patients, good in 18 patients, and poor in one patient. Four patients experienced a recurrence of lesions with lagophthalmos, drooping of the corner of the mouth, partial wound necrosis, and scar widening found in one patient each. Conclusion: Because the head and neck region is the most exposed area in the body, more active implementation of surgical treatments with or without sclerotherapy is essential to reduce the functional and cosmetic impairments associated with venous malformations.

• 스마트미디어저널
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• 제8권1호
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• pp.9-18
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• 2019

4차 산업혁명 시대에 사물인터넷과 모바일을 통해 수집된 다양한 정보를 이용해 공공 및 민간영역의 새로운 비즈니스모델을 위한 빅데이터 산업이 각광을 받고 있다. 하지만, 개인정보 비식별화 조치를 통한 빅데이터 통합 및 분석를 수행하면서 개인프라이버시가 노출될 위험성을 여전히 가지고 있다. 최근 개인정보를 노출하지 않고 데이터의 가치를 유지하는 방법에 대한 연구가 진행되고 있다. 본 논문에서는 빅데이터산업 활성화를 위해 의료, 농업 등 산업별로 개인정보 보호체계가 필요함을 강조하였다. 비식별화된 개인정보의 적정성 평가 기준을 개인 민감정보 중심의 의료분야는 k-익명성 최소값을 일반적인 산업분야의 평균값 보다 높은 5 이상으로 설정해야하며, 농업분야에서는 개인별 민감정보범위에 개인소유 반려견이나 농지 정보를 포함시켜서, 산업별 특성에 맞게 개인정보 보호체계를 보완해야하며, 해당 산업의 특정지역을 대상으로 먼저 실증을 거처 전국적으로 확산하는 것을 제안한다.