• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.1393-1397
• /
• 2005

홍수유출을 저감시키기 위해서 유역의 저류기능을 강화시킬 수 있는 댐 건설은 이수적인 측면에서 안정적인 용수공급을 보장해주는 수단으로 겸용되어 왔으며, 특히 다목적댐이 건설되면서 하도의 첨두홍수유출량을 줄이는데 크게 기여해 왔다. 하지만 그로 인해 물의 흐름이 막히는 정체수역이 증가하고 있으며, 생활오수, 산업폐수의 발생은 정체수역에서의 영양염류 부하량을 증가시켜 부영양화를 초래하고 있다. 수생식물은 태양빛을 받아 광합성 작용을 하여 수중에서 성장하면서 수중의 유$\cdot$무기물질을 영양소로 섭취함으로써 수질을 정화시키는 작용을 하게 된다. 영양염류 부하량이 큰 정체수역의 오염된 물은 식물의 성장활동에 의해서 어느 정도 정화시킬 수 있으며, 이와 같이 수중에 식물을 식재하기 위해서는 식물이 하상에 쉽게 그리고 지속적으로 성장하고 번식활동을 할 수 있는 여건이 필요하다. 따라서 본 연구에서는 Mattress/Filter를 정체수역에 설치함으로써 이러한 식물의 성장과 번식을 도와줄 수 있는 환경조건을 제안하였다. 연구결과, Mattress에 식재한 갈대, 줄 및 애기부들의 피도는 $60-80\%$ 정도로 나타났다. 각 Mattress의 식물군집에는 초기 식재한 식물의 우점도가 가장 높았으나 갈대와 줄 군락의 경우 다른 종이 많이 출현하는 것으로 나타났다. 갈대 군락에서는 갈대가 크게 우점하였으나 그 외에 돌피, 하늘지기, 여뀌바늘 등이 우점하는 것으로 나타났다. 또한 줄 군락에서는 역시 줄이 크게 우점하였으나 방동사니, 돌피, 조개풀 등이 출현하였다. 애기부들 군락에서는 애기부들외에 세모고랭이와 미국가막사리 두가지 종만 출현한 것으로 나타났다. 갈대와 줄 군락의 출현 종수는 각각 7과 11이었으며, 다양도지수가 1.67, 2.18로 식물다양성이 크게 증가한 것으로 나타났다. 수질은 BOD 10mg/L, TN 15mg/L, TP 2.0mg/L이하로 이를 유등천 상류부에 공급할 경우 유등천의 수질은 BOD 6.7mg/L, TN 9.80mg/L, TP 0.90mg/L를 나타낼 것으로 예측된다. 고도처리시설의 도입 후 금강 합류점에서 갑천의 예측 BOD는 7.4mg/L로 현재 9.0mg/L에 비하여 개선되지만 이는 금강수계 오염총량 관리계획의 시$\cdot$도 경계지점 목표수질인 5.9mg/L를 만족시키지 못하므로, 이를 만족시키기 위해서는 방류수 BOD 7.2mg/L이하로 처리해야 할 것으로 판단된다.which support only concepts or image features.방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고

• International Commerce and Information Review
• /
• v.13 no.3
• /
• pp.353-375
• /
• 2011

Export control was first triggered by international export control system at US led COCOM in 1949. Numerous international efforts such as NPT in 1969, ZC in 1970, NSG in 1978, AG in 1985, MTCR in 1987, Wassenaar Arrangement(WA) establishment in 1995 with 1990's the fall of the Berlin Wall, have been made since. The concept of export control has been changed from weaponry and parts export control to preventing or blocking weaponry, respective goods and relevant technology from the hand of troubled regions and non-state actors as terrorist groups; and the new concept is described as Nonproliferation Control. Extent of control items is not only limited to conventional weaponry, but also includes weapons of mass destruction(WMD) and even dual use items which can be used for production, development, usage or storage. Control items include all items defined by NSG, MTCR, AG, WA, and CMC-Opec. The 9.11 terror had a strong influence on international society. Effort to prevent WMD proliferation has now become the most important issue for international security. This study aims to suggest improvement points for nonproliferation law and its effective implementation, based on problem and limitation identification along with analysis of nonproliferation law and implementation examples by type. Furthermore for the purpose of national and global security, export control system on strategic items which are considered to be a key issue in South and North Korea relationship needs to be effectively managed. Recently, North Korea's missile and nuclear tests have been criticized globally; and the global society including respective countries as China and South Korea is striving to urge export control in line with the UN resolution.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.4 no.2
• /
• pp.80-85
• /
• 2002

This study was conducted to investigate the effects of night illumination on the growth and yield of sesame(Sesamum indicum) and perilla(Perilla frutescens). Stem length and height of the first pod in sesame increased, whereas number of branch was reduced and flowering date and maturing date delayed as light intensity of night illumination increased. Number of capsules per plant, ripening ratio and seed yield of sesame were reduced as light intensity of night illumination increased. Yield reduction was greater in Ahnsankkae than in Sodunkkae. Number of nodes increased under night illumination in perilla. Two test cultivars showed reduction in number of branch at 6~10 Lx(22 ㎽ m$^{-2}$ ) intensity of night illumination, even though there was a variation between cultivars. Perilla was sensitive to night illumination far flowering and ripening. Flowering date was delayed by 21 to 28 days at 6~10 Lx intensity of night illumination. Number of flower clusters, number of seeds per flower cluster, and 1,000-seed weight in perilla were significantly reduced and seed yield was reduced by 89 to 98% at 6-10 Lx intensity of night illumination.

• Journal of Advanced Navigation Technology
• /
• v.19 no.6
• /
• pp.623-629
• /
• 2015

In the present study, a coplanar waveguide (CPW)-fed printed monopole antenna with an inverted n-shaped slot is newly proposed for dual band operations which cover bandwidths of CDMA (1.85~2.025 GHz) and WLAN (2.4~2.484 GHz) as well as implementation of omnidirectional radiation pattern. For enhancement of impedance bandwidth ($S11{\leq}10dB$) in 2.4 GHz WLAN frequency band, an inverted n-shaped slot instead of the previous n-shaped slot is etched on the printed radiating monopole. The proposed antenna is designed and fabricated on one side of FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm, and size of $50{\times}25mm^2$. It has been observed that the measured impedance bandwidths are 280 MHz (1.84~2.12 GHz) in frequency band of CDMA and 420 MHz (2.38~2.8 GHz) in WLAN frequency band respectively. It is noticeable that impedance bandwidth in 2.4 GHz frequency band of WLAN is enlarged to three times due to use of inverted L-shaped slot in comparison with impedance bandwidth 140 MHz (2.39~2.53 GHz) obtained by use of the previous n-shaped slot. In addition, good omnidirectional radiation patterns have been observed over the entire frequency band of interest.

• Applied Biological Chemistry
• /
• v.36 no.2
• /
• pp.115-120
• /
• 1993

For the elucidation of some information on processing properties of tomato, physicochemical characteristics of fruits were analysed for two group of cultivation pattern, non-proped cultivation (5 varieties) and groped cultivation (4 varieties). Weight, length, width, thickness and specific gravity were greater in the groped cultivation group than in the non-groped. Among the groped varieties, Master 2 showed the greatest values and 76Mo11-3-1-2-2 the smallest. Among the non-groped, weight, length, width and specific gravity were greatest in Jinhong and thickness was greatest in Good Hope and smallest in $79078{\times}ARC$. Hardness showed significant difference only among the non-groped resulting in the lowest value in $79078{\times}ARC$. Fruit sphericity was greater in the non-groped among which Good Hope was the greatest. In fruit color the non-groped showed greater trend in dominant wavelength, especially in Good Hope. No significant difference between group was found in lightness and % chroma. Sugar content showed higher trend in the non-groped and highest in Master 2. Acidity was significantly higher in the non-groped and highest in Good Hope. There was no difference in pH. Vitamin C was difference between group but higher trend in $79078{\times}ARC$. Viscosity was no difference between group but higher trend in $79078{\times}CL1561F6$ of the non-groped and 76Mo11-3-1-2-2-of the groped.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.5
• /
• pp.82-88
• /
• 2018

This study investigated the structure of an 8-pole 8-slot linear generator, which acts as an electromagnetic damper by combining the structure of an electromagnetic suspension device capable of generating electrical energy through energy harvesting by absorbing the vibration energy from the road surface while driving. To compare the energy harvesting effect of the electromagnetic suspension according to the actual road surface, a driving road test was simulated for two actual road conditions, an asphalt road surface and unpacked road surface condition, using a civilian combined vehicle model in conjunction with a vehicle simulation program, Carsim and Simulink. As a result, the relative displacements of the suspensions on the asphalt road surface and the unpaved road were 8 mm and 13 mm, respectively. By applying the suspension displacement value derived by modeling the linear generator coupled to the electromagnetic suspension, the simulation was then performed for an analysis time of 0.3s by applying the same analytical conditions using the commercial electromagnetic analysis program, ANSYS MAXWELL, The average power generation on the unpacked roads and asphalt roads was 198.6W and 98.7W respectively, which was 103.7% higher for unpackaged roads. Finally, to compare the sensitivity of the road surface frequency and the suspension input displacement to the power generation output, the sensitivity of the two variables was 1.725 and 1.283, respectively, and the road surface frequency had a 34.5% higher effect on the average power generation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.433-442
• /
• 2017

This study consists of five case studies of the catering facilities of newly-built elementary schools' in Sejong City, regarding the spatial configuration and allocation. The analysis indicated that the space allocated in the cooking area in the five schools compared to the standard was as follows: School A; 99.2%, B; 91.1%, C; 81.4%, D; 110.8%, E; 88.1%. Accordingly, the cooking area was close to, or slightly above the standard; nevertheless, other areas in the facilities were not allocated sufficient space and were not appropriately planned. Among the other findings, the receiving areas of three schools were not even planned, and the receiving works were carried out in the pre-preparation area. Considering the flow of the dish-washing process, the width of the room should be at least 3.6 meters with a passage width of 1.6 meters, and easy access to the cooking and dining areas must be equipped. An interview with all five supervisors showed that most complaints focused on the cooking and dishwashing areas, whereas there were none in the storage and workers' area. The result highlights the importance of the cooking and dishwashing areas as the main functions in catering facilities, and future planning strategies should consider this aspect.

• Journal of Satellite, Information and Communications
• /
• v.7 no.3
• /
• pp.99-104
• /
• 2012

The United States will proceed with the effort to modernize the GPS system, and one of its main content is to provide L5 signal. L5 will be transmitted in a radio band reserved exclusively for aviation safety services. And, L5, in combination with L1, will improve the position accuracy via ionospheric correction and robustness via signal redundancy. However, The acquisition processing time of L5 takes longer than that of L1 as the code length of L5 is 10 times longer than that of L1. To reduce this acquisition processing time, a higher number of correlators in the aquisition module should be used. However, there is a problem that this causes increase in the complexity of the correlator configuration and the computation power. So, in this paper, we propose L5 signal tracking scheme using tracking results in the GPS L1/L5 receiver. The proposed scheme could reduce the hardware complexity as the GPS L5 signal acquisition module is not needed, and provide fast and stable tracking of L5 signal by aiding L1 tracking results such as PRN, the code phase synchronization, and the Doppler frequency. The feasibility of the proposed scheme is demonstrated through simulation results.

• Journal of Korea Water Resources Association
• /
• v.48 no.8
• /
• pp.659-672
• /
• 2015

In flow velocity measurement of natural rivers, taking images with proper image quality is the fundamental and the most important step. Since flood peaks generally occur in night time, it is very difficult to capture proper images in that time. The present study aims to test a far infra-red camera as a adequate alternative to resolve the various problems in measuring flood discharges. The far infra-red cameras are able to capture images in night time without help of any extra illuminations. Futhermore they are not affected by fog nor smoke, hence they can be adapted for a fixed-type surface image velocimeters. For comparison, a commercial camcorder and a near infra-red cameras were used together. The test images were taken at a day time and a night time, and the image acquisition work were performed at an artificial flow channel of the Andong River Experiment Station. The analyzed results showed that the far infra-red camera would be a good instrument for surface image velocimeters, since they were able to capture regardless light condition. There are, however, a few minor problems in their accuracy of the analyzed results. About their accuracy a more study would be required.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.17 no.8 s.111
• /
• pp.773-787
• /
• 2006

An airborne radar is an essential aviation electronic system for the aircraft to perform various civil and/or military missions in all weather environments. This paper presents the design, development, and test results of the multi-mode X-band pulsed Doppler radar system test model for helicopter-borne flight test. This radar system consists of 4 LRUs(Line-Replacement Unit), which include antenna unit, transmitter and receiver unit, radar signal & data processing unit and display Unit. The developed core technologies include the planar array antenna, TWTA transmitter, coherent I/Q detector, digital pulse compression, MTI, DSP based Doppler FFT filter, adaptive CFAR, moving clutter compensation, platform motion stabilizer, and tracking capability. The design performance of the developed radar system is verified through various ground fixed and moving vehicle test as well as helicopter-borne field tests including MTD(Moving Target Detector) capability for the Doppler compensation due to the moving platform motion.