• Title/Summary/Keyword: Blind area

Search Result 193, Processing Time 0.026 seconds

A study on installation location of radar for minimizing blind area in the construction of VTS system of Kangjeong Port (강정항 VTS 시스템 구축시 음영구역 최소화를 위한 레이더의 위치설정에 관한 연구)

  • LEE, Seung-Hi;KIM, Kwang-Il;AHN, Jang-young;LEE, Chang-Heon;CHOI, Chan-Moon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.53 no.2
    • /
    • pp.187-195
    • /
    • 2017
  • We have studied the efficient operation of the radar and the appropriateness of the installation location, when constructing the VTS system. As the Civil-Military Complex Harbour (Kangjeong Port) is completed in 2016, we set the control area within 10 nautical miles centering on Kangjeong Port, and found out and removed the operational radar blind area of VTS system to provide safe navigation information for vessels that navigating this area. Assuming that two international cruise ships entering at the same time, we performed the radar simulation and compared the images by considering the three sites of Kangjeong Port, Miaksan and Seoguipo Port. Simulation results for a single radar installed at Kangjung Port indicate that the blind area was largely affected by two large cruise ships and the surrounding islands. The blind area due to Kogunsan was considerably large when installed in Miaksan, but the blind area due to the influences of Beomseom, Moonseom and Seopseom was negligibly large. It seems that additional radar installation is necessary as a complementary solution to solve this blind area. When two radars were installed at Miaksan and Kangjeong Port, the residual blind area due to the Seopseom was $0.25km^2$ at 0.1~0.33 nautical miles in the southeast direction from Seopseom. In addition, the remaining blind area with two cruise ships mutually influenced was $0.18km^2$, which did not occur with a single cruise ship.

Monitoring System of Blind Areas in a Skiing Resort using a USN (USN을 이용한 스키장 사각 지역 감시 시스템)

  • Lee, Hyung-Bong;Jung, Ui-Min;Park, Lae-Jeong;Moon, Jung-Ho;Chung, Tae-Yun
    • The KIPS Transactions:PartD
    • /
    • v.16D no.2
    • /
    • pp.249-256
    • /
    • 2009
  • This paper introduces an efficient USN (ubiquitous sensor network) for monitoring blind areas in a skiing resort, developed as a part of u-Sport showcase project of Gangwon Province. Blind areas of a skiing resort are dangerous and/or steep areas located aroud ski slopes, which are rarely traveled and not easily seen by a ski patrol. If an accident occurs in such a blind area, the main control center of the sking resort can hardly recognize the accident and provide first aid and rescue services promptly. The blind area monitoring system proposed in this paper monitors a blind area of a skiing resort using five battery-powered sensor nodes each of which has an image sensor on it and wirelessly transmits images around the blind area to the main control center on a regular basis, therebly allowing real-time monitoring of the blind area and prompt rescue services in case of accidents. Additionally, the monitoring system provides an emergency button which skiers injured in the blind area can push. If the button is pushed, an image around the button and an alarm signal are transmitted to the main control center and therefore the main control center can take prompt actions for rescuing the injured skiers.

New Vehicle Verification Scheme for Blind Spot Area Based on Imaging Sensor System

  • Hong, Gwang-Soo;Lee, Jong-Hyeok;Lee, Young-Woon;Kim, Byung-Gyu
    • Journal of Multimedia Information System
    • /
    • v.4 no.1
    • /
    • pp.9-18
    • /
    • 2017
  • Ubiquitous computing is a novel paradigm that is rapidly gaining in the scenario of wireless communications and telecommunications for realizing smart world. As rapid development of sensor technology, smart sensor system becomes more popular in automobile or vehicle. In this study, a new vehicle detection mechanism in real-time for blind spot area is proposed based on imaging sensors. To determine the position of other vehicles on the road is important for operation of driver assistance systems (DASs) to increase driving safety. As the result, blind spot detection of vehicles is addressed using an automobile detection algorithm for blind spots. The proposed vehicle verification utilizes the height and angle of a rear-looking vehicle mounted camera. Candidate vehicle information is extracted using adaptive shadow detection based on brightness values of an image of a vehicle area. The vehicle is verified using a training set with Haar-like features of candidate vehicles. Using these processes, moving vehicles can be detected in blind spots. The detection ratio of true vehicles was 91.1% in blind spots based on various experimental results.

Effects of Stocking Density on the Blind-side Hypermelanosis of Cultured Olive Flounder Paralichthys olivaceus

  • Kang, Duk-Young;Kim, Hyo-Chan;Chang, Young-Jin
    • Fisheries and Aquatic Sciences
    • /
    • v.14 no.2
    • /
    • pp.123-129
    • /
    • 2011
  • To determine whether rearing density affects the hypermelanosis on the blind side (ambicoloration) of olive flounders Paralichthys olivaceus, we reared fry with an unpigmented non-eyed (blind) side in duplicate at densities of 150 individuals/$m^2$ (commercial production density: control) and 450 individuals/$m^2$ (high density group) for 90 days in 1-t dark-green fiberglass reinforced plastics (FRP) tank. We recorded feed intake, feed conversion efficiency (FE), growth and survival, and measured the ratios of staining blind-side area (staining area) and ambicolored fish every 30 days. Daily feed intake (DFI), feed conversion efficiency (FE), growth rate, condition factors, and survival rate were calculated at the end of the experiment. Although the FE was higher in the high-density compared to the control, the two density groups showed similar feed intakes, growth, and survival. The ratio of staining area as well as the ratio of ambicolored fish significantly were significantly higher in the high-density group than in the control from days 30 to 60, but significantly increased and evened out by the end of the experiment (P<0.05). In conclusion, we determined that rearing density is not the main cause of the blind-side hypermelanosis, but found that increasing the rearing density can accelerate the ambicoloration in olive flounders.

Daylight Assessment of Venetian Blind by Shading Heights and Slat Angles (베네시안 블라인드의 높이와 슬랫각도 조절에 따른 계절별 실내주광분포 분석)

  • Shin, Hwa-Young;Kim, Gon;Kim, Jeong Tai
    • KIEAE Journal
    • /
    • v.11 no.2
    • /
    • pp.105-111
    • /
    • 2011
  • Aims of this study is to investigate the daylighting control strategy of venetian blind system was performed as a function of ratio of shading height to window and slat angles in the preliminary stage of the parametric study. Floor-to-ceiling window walls of living spaces are used widely in apartment buildings since the Korean government has legally allowed elimination of the balcony area. Enlarging living area by balcony elimination, the larger glass area of window is exposed to the direct sunlight. As a common sunlight controlling device, blind system can be used in all orientations and all latitudes and it may obstruct, absorb, reflect and transmit solar radiation to building by proper adjusting. However, blind system can produce discomfort in occupant and less energy efficiency, if it has not been controlled optimally. The simulation model was based on the unit module of typical living space with balcony elimination. The room dimension was $6.0m(w){\times}6.9m(d){\times}2.7m(h)$ with floor to ceiling height of 2.5m. The blind system was simulated at five slat angles (horizontal, $30^{\circ}$, $45^{\circ}$ upward and downward tilted) and the four ratio of shading height to window (fully closed, partly opened, no-blind) using the Desktop RADIANCE 2.0 program. The series of simulation results indicates that the advantages of available daylight and outside of view can be improved by proper adjusting blind system.

A performance Enhancement of VANET Warning Message Propagation on Electric Wave Blind Area Problem in the Urban Environment (도심의 전파 사각 지역 문제 해결을 위한 VANET 경고 메시지 전달 기능의 개선)

  • Lee, Won Yeoul
    • Journal of Korea Multimedia Society
    • /
    • v.17 no.10
    • /
    • pp.1220-1228
    • /
    • 2014
  • Emergency Warning Service will be the most important service of VANET. Transmission delay is the most important performance criteria of the warning service. Most legacy research takes a way to minimize the packet collision. However those approach has a critical weak point on urban environment where there is a blind area of electric wave. So another issue is required in order to provide enhanced warning message propagation technique to overcome the urban environment problem. In this paper, I proposed an enhanced warning message propagation scheme in the poor electric wave environment as the intersection area. Proposed scheme forwards the warning message to the blind area by enhanced forwarding node selection technique. For efficiency of warning message propagation, I suggest forwarding priority for decision of forwarding node. And the node has a direct mode or redirect mode depending on neighbor nodes. The simulation was carried out to evaluate the performance. The simulation results show that proposed scheme has the superior performance compared to legacy warning message technique.

Morphological Analysis of Blind-Side Hypermelanosis of the Starry Flounder, Platichthys stellatus during Early Development

  • Kang, Duk-Young;Byun, Soon-Gyu;Myeong, Jeong-In;Kim, Hyo-Chan;Min, Byoung-Hwa
    • Development and Reproduction
    • /
    • v.18 no.2
    • /
    • pp.79-87
    • /
    • 2014
  • In Pleuronectiformes, blind-side malpigmentation (hypermelanosis) is common in cultured flatfishes, and is economically important. To understand the mechanism of blind-side hypermelanosis in flatfishes, we examined when the malpigmentation initially occurred, and studied how the symptoms proceeded during early development of the starry flounder, Platichthys stellatus. To assess quantitative pattern changes of blind-side skin, we observed morphological development of the whole body from 22 (total length [TL] $10.0{\pm}0.2$ mm and body weight [BW] $8.8{\pm}0.57$ mg) to 110 days (TL $23.4{\pm}0.7$ mm, BW $193.6{\pm}23.3$ mg) after hatching (DAH), and also examined the malpigmented area rate of blind-side skin and the malpigmented fish ratios. The experimental animals were reared in fiberglass-reinforced plastic (FRP) tanks in water at a temperature of $18.9{\pm}1.9^{\circ}C$ and salinity of $32.6{\pm}0.6$ psu and were fed with rotifer and Artemia nauplii from 22 to 48 DAH, and with A. nauplii and commercial feed from 49 to 110 DAH. As results, the first staining patch seen by the naked eye was observed around the area between the anus and pelvic fin or caudal edge of the trunk at 80 DAH (TL $20.6{\pm}0.5$ mm, BW $112.5{\pm}8.8$ mg). The pigmented area and the pigmented fish ratios were significantly increased from 80 to 110 DAH. These results indicated that malpigmentation on the blind side of starry flounder was initially observed at about 2 cm in length and 100 mg in weight, and the pigmented domain on the blind-side skin was continually broadened by the differentiation of pigmented cells (melanophores and xanthophores) with growth.

Bedrock Depth Variations and Their Applications to identify Blind Faults in the Pohang area using the Horizontal-to-Vertical Spectral Ratio (HVSR) (포항지역 HVSR에 의한 기반암 심도와 단층 식별 연구)

  • Kang, Su Young;Kim, Kwang-Hee
    • Journal of the Korean earth science society
    • /
    • v.43 no.1
    • /
    • pp.188-198
    • /
    • 2022
  • Some deep faults do not reach the ground surface and are seldom recognized. Gokgang Fault area in the east of the Heunghae area of the Pohang basin has been selected to confirm the feasibility of the Horizontal-to-Vertical Spectral Ratio (HVSR) approach to identify blind faults. Densely spaced microtremor data have been acquired along two lines in the study area and processed to obtain resonance frequencies. An empirical relationship between the resonance frequency and the bedrock depth was proposed using borehole data available in the study area. Resonance frequencies along two lines were then converted to bedrock depths. The resulting depth profiles show significant lateral variations in the bedrock depth. As expected, considerable variation in the resonance frequency is observed near the Gokgang fault. The depth profiles also present additional significant variations in the resonance frequencies and the bedrock depths. The feature is presumably related to a blind fault that is previously unknown. Therefore, this case study confirms the feasibility of the HVSR technique to identify faults otherwise not recognized on the surface.

The Visual Performance Evaluation of the Work planes with the Automated blind Control in Small Office Spaces

  • Park, Doo-Yong;Yoon, Kap-Chun;Kim, Kang-Soo
    • KIEAE Journal
    • /
    • v.14 no.1
    • /
    • pp.15-22
    • /
    • 2014
  • Among the various building envelope elements, the glass area takes up the largest portion in the office building design. However, a large area of glass can cause problems such as excessive solar radiation, thermal comfort, and glare. Thus it is important to install the glass area to an appropriate level, and control solar radiation and inflow of daylight with blind devices. This study aims to improve the visual performance of the work plane through the automatic control of the venetian blinds. A total of eight kinds of control strategies were chosen; Case 1 does not control the blinds, Case 2 with the blind slats fixed at the angle of 0 degree, Case 3 to 6 using the existing blind control programs, and Case 7 and 8 with improved blind control. Case 3 with 90 degrees had the best energy performance, but the average indoor illuminance was 113lux, which is below the standards. Cases 4 and 5 showed higher levels of interior daylight illuminance with the average of 281lux and 403lux respectively. However, the fixed angles may have difficulties controlling excessive direct sunlight coming into the room and may cause glare. Cases 6 and 7 used sun tracking angle control and cut-off angle control, and the average interior illuminance was measured 250lux and 385lux respectively. Case 8 used the cut-off angle control in an hourly manner, satisfying the standard illuminance of 400lux with an average interior illuminance of 561lux. It was evaluated to be the best method to control direct solar radiation and to guarantee proper level of interior illumination.

Influence of Background Color and Substratum on the Blind-side Hypermelanosis in Starry Flounder Plathchthys stellatus (강도다리(Platichthys stellatus) 흑화 발현에 미치는 수조색깔 및 자갈기질의 영향)

  • KIM, Won-Jin
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.28 no.3
    • /
    • pp.841-847
    • /
    • 2016
  • To study the influence of background color and substratum on hypermelanosis of starry flounder, we compared the daily food intake (DFI), the feed efficiency (FE), the survival, the growth, the ratio of pigmented area on the blind side and the ratio of hypermelanic fish duplicately reared for 180 days in dark-green FRP aquarium (control), white FRP aquarium together with dark-green substratum. The ratio of pigmented area on the blind side was significantly higher at the dark-green group than at the white group. DFI, FE and growth were higher in the dark-green substratum. Pigmented area rate and ratio of hypermelanic fish were significantly higher at the dark green group than at the high dark-green substratum. The results suggest that bright tank color and substratum bottom could inhibit the hypermelanosis.