• Title/Summary/Keyword: distance functions

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Application of Echo-Sounder Monitoring Technique as Ecological Impact Assessments of Fish on Artificial Weir Construction (인공보의 어류생태영향 평가를 위한 Echo-sounder 모니터링 기법 적용)

  • Han, Jeong-Ho;Lee, Jae Hoon;Choi, Ji-Woong;Lim, Byung Jin;Park, Jong-Hwan;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.21 no.6
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    • pp.859-877
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    • 2012
  • In this study, Echo-sounder($E_s$) monitoring methodology was applied to test environmental impacts of artificial weirs(SCW and JSW) in the Yeongsan River on fish community and habitat structures at first time, and was compared with conventional fish sampling methodologies($C_s$). For the Es monitoring in the fields, parallel transect methods was employed in determining the survey distance interval with every 125 m within the upper-lower 2 km of the weirs. Four different fish sampling gears such as casting nets, kick nets, fyke nets, and gill nets were used for applications of $C_s$ monitoring methodology. According to the Echo-sounder monitoring, fish density, expressed as a number of individuals per square meter, along the longitudinal axis of the weir was significantly greater(JSW, t = 3.506, n = 30, p < 0.001) in the down-river reach of the weir than in the up-river reach. Also, fish density along the vertical water column was highest at mid-depths of Seungchon weir, which has simple habitat substrates, while fish density was highest at hypolimnetic depth of Juksan weir. According to fish sampling by the $C_s$ methodology, the fish compositions decreased as the river goes upward, and significant differences(JSW, t = 0.248, n = 30, p < 0.05) in the compositions of fish species occurred between up-reach and down-reach of the weirs. The dominant species near the two weirs were Opsarichthys uncirostris amurensis, Hemiculter eigenmanni and Coilia nasus. Overall, our fish and habitat data, based on $E_s$ and $C_s$ monitoring methodologies, suggest that the weirs disturbed the rivers due to initial habitat disturbances by the weir constructions as well as the barrier roles of weirs on fish passage and migrations. More long-term scientific and systematic fish impact monitoring and assessments($E_s$ and $C_s$) are required in the future to predict changes of ecological structures and functions on the constructions of the weirs.

Design and Implementation of the Stop line and Crosswalk Recognition Algorithm for Autonomous UGV (자율 주행 UGV를 위한 정지선과 횡단보도 인식 알고리즘 설계 및 구현)

  • Lee, Jae Hwan;Yoon, Heebyung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.3
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    • pp.271-278
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    • 2014
  • In spite of that stop line and crosswalk should be aware of the most basic objects in transportation system, its features extracted are very limited. In addition to image-based recognition technology, laser and RF, GPS/INS recognition technology, it is difficult to recognize. For this reason, the limited research in this area has been done. In this paper, the algorithm to recognize the stop line and crosswalk is designed and implemented using image-based recognition technology with the images input through a vision sensor. This algorithm consists of three functions.; One is to select the area, in advance, needed for feature extraction in order to speed up the data processing, 'Region of Interest', another is to process the images only that white color is detected more than a certain proportion in order to remove the unnecessary operation, 'Color Pattern Inspection', the other is 'Feature Extraction and Recognition', which is to extract the edge features and compare this to the previously-modeled one to identify the stop line and crosswalk. For this, especially by using case based feature comparison algorithm, it can identify either both stop line and crosswalk exist or just one exists. Also the proposed algorithm is to develop existing researches by comparing and analysing effect of in-vehicle camera installation and changes in recognition rate of distance estimation and various constraints such as backlight and shadow.

Measurement of Electron Temperature and Number Density and Their Effects on Reactive Species Formation in a DC Underwater Capillary Discharge

  • Ahmed, Muhammad Waqar;Rahman, Md. Shahinur;Choi, Sooseok;Shaislamov, Ulugbek;Yang, Jong-Keun;Suresh, Rai;Lee, Heon-Ju
    • Applied Science and Convergence Technology
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    • v.26 no.5
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    • pp.118-128
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    • 2017
  • The scope of this work is to determine and compare the effect of electron temperature ($T_e$) and number density ($N_e$) on the yield rate and concentration of reactive chemical species ($^{\bullet}OH$, $H_2O_2$ and $O_3$) in an argon, air and oxygen injected negative DC (0-4 kV) capillary discharge with water flow(0.1 L/min). The discharge was created between tungsten pin-to pin electrodes (${\Phi}=0.5mm$) separated by a variable distance (1-2 mm) in a quartz capillary tube (2 mm inner diameter, 4 mm outer diameter), with various gas injection rates (100-800 sccm). Optical emission spectroscopy (OES) of the hydrogen Balmer lines was carried out to investigate the line shapes and intensities as functions of the discharge parameters such as the type of gas, gas injection rate and inter electrode gap distances. The intensity ratio method was used to calculate $T_e$ and Stark broadening of Balmer ${\beta}$ lines was adopted to determine $N_e$. The effects of $T_e$ and $N_e$ on the reactive chemical species formation were evaluated and presented. The enhancement in yield rate of reactive chemical species was revealed at the higher electron temperature, higher gas injection rates, higher discharge power and larger inter-electrode gap. The discharge with oxygen injection was the most effective one for increasing the reactive chemical species concentration. The formation of reactive chemical species was shown more directly related to $T_e$ than $N_e$ in a flowing water gas injected negative DC capillary discharge.

Development of Java/VRML-based 3D GIS's Framework and Its Prototype Model (Java/VRML기반 3차원 GIS의 기본 구조와 프로토타입 모델 개발)

  • Kim, Kyong-Ho;Lee, Ki-Won;Lee, Jong-Hun
    • Journal of Korean Society for Geospatial Information Science
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    • v.6 no.1 s.11
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    • pp.11-17
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    • 1998
  • Recently, 3D GIS based on 3D geo-processing methodology and Internet environment are emerging issues in GIS fields. To design and implement 3D GIS, the strategic linkage of Java and VRML is first regarded: 3D feature format definition in the passion of conventional GIS including aspatial attributes, 3B feature indexing, 3D analytical operators such as selection, buffering, and Near, Metric operation such as distance measurement and statistical description, and 3D visualization. In 3D feature format definition, the following aspects are implemented: spatial information for 3D primitives extended from 2D primitives, multimedia data, object texture or color of VRML specification. DXF-format GIS layers with additional attributes are converted to 3D feature format and imported into this system. While, 3D analytical operators are realized in the form of 3D buffering with respect to user-defined point, line, polygon, and 3D objects, and 3D Near functions; furthermore, 'Lantern operator' is newly introduced in this 3D GIS. Because this system is implemented by Java applet, any client with Java-enable browser including VRML browser plug-in can utilize the new style of 3D GIS function in the virtual space. Conclusively, we present prototype of WWW-based 3D GIS, and this approach will be contribute to development of core modules on the stage of concept establishment and of real application model in future.

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Vision and Aging

  • Kim, In Suk;Hilz, Rudolf
    • Journal of Korean Ophthalmic Optics Society
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    • v.7 no.1
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    • pp.9-13
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    • 2002
  • It is well known that the maximum amplitude of accommodation decreases with increasing age.(Presbyopia). With single vision lenses presbyopia can be corrected only for one viewing distance. With progressive power lenses presbyopia can be corrected for all viewing distances. But there are some other changes in the visual system with age which can not be corrected by spectacle lenses. Pupillary diameter decreases and the light transmission of the ocular media decreases. Therefore old people need more light, they need better illumination. Cone density in the retina decreases, this is only one example for changes in the sensory system. These changes in the visual system cause changes in visual functions. At the age of 80 visual acuity has decreased to half. Contrast sensitivity for gratings decreases mainly for high spatial frequencies very important is the increase of stray light in the ocular media and therefore the increase of glare. Veiling luminance increases by a multiple of approximately 4, Dark adaptation gets slower and light sensitivity is approximately 2 log units (factor 100) less when the eye is completely dark adapted. Also colour vision gets worse, especially at low luminances. Elderly people have problems with visual tasks which require divided attention between foveal and peripheral vision. An example is the measurement of the useful field of view. This useful field of view be expanded (improved) by visual training.

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The Natures of Urban Growth and Newly Developed Districts of Taegu(II) - The Case of Newly Developed Districts of Sangin and Siji - (대구시의 도시성장과 신시가지 지역 특성에 관한 연구(II) - 상인 및 시지 신시가지의 사례를 중심으로 -)

  • Jin, Won-Hyung
    • Journal of the Korean association of regional geographers
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    • v.8 no.4
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    • pp.430-450
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    • 2002
  • This study empirically analyses the spatial features of land use and transportation, and residential characteristics of the cases of the Sangin and Siji newly developed districts in Taegu. Before the development, the areas consisted mainly of rice paddies and fields; these areas are now filled with high-density residential complexes, with a proliferation of commerce and service functions. In Sangin, restaurants, retail services, bars and bakeries are the main developments, but Siji developed retail services, restaurants, private institutions for students, and facilities for convenience goods. While the public transportation system is oriented to CBD, the inter-districts transportation network is lacking. The residents are mainly in their 40s to 50s, with white collar jobs. They have a relatively high level of education with high income. They have migrated a relatively short distance to the district. The locational(pull) factors influencing the decision to migrate, for Sangin are transportation, the physical environment and access to the working place, but for Siji it has been the physical environment, the school group, and access to the working place. The main dissatisfaction factors for Sangin are the management fee, the school group and for Siji they are commuting, the management fee and transportation.

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Effect of Volleyball Program on Physical Fitness and Attention Concentration of Middle School Students with Intellectual Disabilities (배구 프로그램이 중학교 지적장애학생의 체력과 주의집중력에 미치는 효과)

  • Bae, Kwang-Youl
    • Journal of Digital Convergence
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    • v.18 no.2
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    • pp.175-182
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    • 2020
  • The study aims to verify the effects of volleyball programs on the fitness and attention-intensive abilities of students with intellectual disabilities in middle school. Physical strength and attention concentration were analyzed to verify the effectiveness of the volleyball program. The volleyball program was applied to the experimental group three times a week, 90 minutes a week, a total of 36 times for 12 weeks. To verify the effectiveness of physical strength and attention concentration, the PPS-D intellectual disability student test and ATA concentration test were used to verify the effectiveness of attention concentration The six-minute walking figure related to cardiopulmonary functions was improved compared to those with intellectual disabilities who did not participate in the volleyball program, the report showed. We can see improvements in muscular function-related sit-ups and flexibility-related sit-ups compared to those with intellectual disabilities who did not participate, and significant changes have been seen in the distance of the place-wide jump related to net worth. We could also confirm that it had a positive effect on the improvement of selective attention concentration, and that the change in self-control, continuous attention, and selective attention among middle school students had a positive effect on the improvement.

Environmental Test Results of a Flight Model of a Compact Imaging Spectrometer for a Microsatellite STSAT-3 (과학기술위성3호 소형영상분광기 발사모델 환경시험 결과)

  • Lee, Sang-Jun;Kim, Jung-Hyun;Lee, Jun-Ho;Lee, Chi-Won;Jang, Tae-Sung;Kang, Kyung-In
    • Korean Journal of Optics and Photonics
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    • v.22 no.4
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    • pp.184-190
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    • 2011
  • A compact imaging spectrometer (COMIS) was developed for a microsatellite STSAT-3. The satellite is now rescheduled to be launched into a low sun-synchronous Earth orbit (~700 km) by the end of 2012. Its main operational goal is the imaging of the Earth's surface and atmosphere with ground sampling distance of 27 m and 2 - 15 nm spectral resolution over visible and near infrared spectrum (0.4 - 1.05 ${\mu}m$). A flight model of COMIS was developed following an engineering model that had successfully demonstrated hyperspectral imaging capability and structural rigidity. In this paper we report the environmental test results of the flight model. The mechanical stiffness of the model was confirmed by a small shift of the natural frequency i.e., < 1% over 10 gRMS random vibration test. Electrical functions of the model were also tested without showing any anomalies during and after vacuum thermal cycling test with < $10^{-5}$ torr and $-30^{\circ}C\;-\;35^{\circ}C$. The imaging capability of the model, represented by a modulation transfer function (MTF) value at the Nyquist frequency, was also kept unvaried after all those environmental tests.

A Study on the Planning Characteristics of Training Facilities Complex - Focusing on Training Facilities Planned through the Domestic Competitions after 2000s - (연수시설 단지의 계획특성 연구 - 2000년대 이후 국내 현상공모를 통해 계획된 연수시설을 중심으로 -)

  • Park, Hoon
    • Journal of the Korean Institute of Educational Facilities
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    • v.25 no.1
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    • pp.13-24
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    • 2018
  • Planning and designing training facilities has been developed from educational facilities, and increasingly diversified society has raised a need for facilities dedicated to training and education in a differentiated space separate from the one for regular works. This particular need of our times has led to the expansion of training facilities nationwide although they have something to be desired when it comes to planning and designing with sustainability associated with the locational characteristics of urban space as well as the unique types of facilities taken into account. Against this backdrop, this study will examined a variety of training facilities that have been established since 2000 through theoretical review and conduct intensive analysis on the characteristics of the planning aspects to suggest their significance and implications and to present the overall meanings and ramifications of planning approaches in consideration of new challenges modern training facilities are faced with, which have been revealed through architectural design competitions in recent years. The relevant implications are as follows. First, one of the locational advantages of training facilities, which is commanding beautiful scenery of the surrounding area, can be considered as intent to stress the aspect of a resort, one of the functions of any training facilities. As this study has demonstrated, many training facilities are located near around a beach or a lake. Second, training facilities can be classified into three different types in terms of their location: urban, suburban and resort and such locational characteristics are directly related to intended programs and differentiated links with target users. Third, the architectural styles of training institutes are differentiated in terms of harmonious arrangement between beautiful natural scenery and buildings in consideration of the layout characteristics of major facilities and the distance of ramps in and out of the facilities along with architectural features, including the transparency of building elevation and the type of slopes of roof structure. Fourth, the individual lodging buildings feature a variety of types depending on the design concept with different roles depending on the directional aspects such as the connection of ramps and the relations with the outside. Fifth, outdoor space plans are differentiated according to the intended purpose of training facilities. When it comes to gym facilities, for example, different outdoor space plans are found to be made depending on the original design concept such as outdoor playground-centered planning or golf facilities.

Development of the Best Spherical Interpolation Method for Estimating Potential Natural Vegetation Distribution of the Globe (지구(地球)의 잠재자연식생분포(潜在自然植生分布)를 추정(推定)하기 위한 최적구면보간법(最適球面補間法)의 개발(開發))

  • Cha, Gyung Soo;Ochiai, Kamiya
    • Journal of Korean Society of Forest Science
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    • v.86 no.1
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    • pp.17-24
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    • 1997
  • As the first step to estimate the potential natural vegetation distribution of the globe, the best spherical interpolation method was developed to the temperature and precipitation which have close relation to the distribution pattern of world natural vegetation. For developing the interpolation method, a named Light Climatic Dataset composed of 1,060 stations around the globe was randomly divided into halves of feeding side and target side. The discrepancy between the observed and estimated values at the target stations was compared with combinations of parameters and methods. The estimated values were calculated to each combination which is all-out, constant radius and constant station methods in the selection of the feeding stations, n square reciprocal and negative exponential functions in weighting function of distance between feeding stations and each target, and oval weighting in direction of the feeding stations from each target. As a result, it turned out that the spherical interpolation with negative exponential weighting function fed from the constant radius stations ovally weighed yields the best estimates both for temperature and for precipitation. The parameters for temperature are $30^{\circ}$ in constant radius, 0.78 in negative exponential function and 0.4 in oval weighting, and for precipitation are $30^{\circ}$, 0.53 and 0.4, respectively.

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