• Title/Summary/Keyword: density variations

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Performance Evaluation of Low-cost Optical Components used for Measuring the Optical Density and Concentration of Particulate Matter(PM) (입자상물질의 광학밀도 및 농도측정에 적용된 저가형 광학 부품의 성능평가)

  • Baik, Young Jo;Hong, Terki;Hwang, Cheol Hong;Park, Seul Hyun
    • Journal of the Korean Society of Safety
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    • v.31 no.5
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    • pp.1-6
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    • 2016
  • The performance of a set of low-cost optical components used for measuring the optical density of PM particles was evaluated in the present study. To this end, the set of low-cost optical components was replaced with that of general optical components used to measure the PM optical density under identical experimental conditions. The optical densities measured from the set of general optical components were then compared to those obtained from the set of low-cost optical components. While the optical density is measured, another key parameter, the dimensionless extinction constant of PM particles (which is needed to optically measure the PM concentration) was also determined in the present study. The experimental results indicate that the optical density and PM concentration measurements performed by low-cost optical components are feasible, producing trackable variations in the OD and concentrations compared to values obtained from the set of general optical components.

Theoretical Study on Hydrophobicity of Amino Acids by the Solvation Free Energy Density Model

  • Kim, Jun-Hyoung;Nam, Ky-Youb;Cho, Kwang-Hwi;Choi, Seung-Hoon;Noh, Jae-Sung;No, Kyoung-Tai
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1742-1750
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    • 2003
  • In order to characterize the hydrophobic parameters of N-acetyl amino acid amides in 1-octanol/water, a theoretical calculation was carried out using a solvation free energy density model. The hydrophobicity parameters of the molecules are obtained with the consideration of the solvation free energy over the solvent volume surrounding the solute, using a grid model. Our method can account for the solvent accessible surface area of the molecules according to conformational variations. Through a comparison of the hydrophobicity of our calculation and that of other experimental/theoretical works, the solvation free energy density model is proven to be a useful tool for the evaluation of the hydrophobicity of amino acids and peptides. In order to evaluate the solvation free energy density model as a method of calculating the activity of drugs using the hydrophobicity of its building blocks, the contracture of Bradykinin potentiating pentapeptide was also predicted from the hydrophobicity of each residue. The solvation free energy density model can be used to employ descriptors for the prediction of peptide activities in drug discovery, as well as to calculate the hydrophobicity of amino acids.

Diurnal Variations in the Horizontal Temperature Distribution using the High Density Urban Climate Observation Network of Daegu in Summer (고밀도 도시기후관측 망 자료를 이용한 대구의 여름철 기온 수평 공간 분포의 일변화)

  • Kim, Sang-Hyun;Kim, Baek-Jo;Kim, Hae-Dong
    • Journal of Environmental Science International
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    • v.25 no.2
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    • pp.259-265
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    • 2016
  • We analyzed diurnal variations in the surface air temperature using the high density urban climate observation network of Daegu in summer, 2013. We compared the time elements, which are characterized by the diurnal variation of surface air temperature. The warming and cooling rates in rural areas are faster than in urban areas. It is mainly due to the difference of surface heat capacity. In addition, local wind circulation also affects the discrepancy of thermal spatiotemporal distribution in Daegu. Namely, the valley and mountain breezes affect diurnal variation of horizontal distribution of air temperature. During daytimes, the air(valley breeze) flows up from urban located at lowlands to higher altitudes of rural areas. The temperature of valley breeze rises gradually as it flows from lowland to upland. Hence the difference of air temperature decreases between urban and rural areas. At nighttime, the mountains cool more rapidly than do low-lying areas, so the air(mountain breeze) becomes denser and sinks toward the valleys(lowlands). As the result, the air temperature becomes lower in rural areas than in urban areas.

New Finger-vein Recognition Method Based on Image Quality Assessment

  • Nguyen, Dat Tien;Park, Young Ho;Shin, Kwang Yong;Park, Kang Ryoung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.2
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    • pp.347-365
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    • 2013
  • The performance of finger-vein recognition methods is limited by camera optical defocusing, the light-scattering effect of skin, and individual variations in the skin depth, density, and thickness of vascular patterns. Consequently, all of these factors may affect the image quality, but few studies have conducted quality assessments of finger-vein images. Therefore, we developed a new finger-vein recognition method based on image quality assessment. This research is novel compared with previous methods in four respects. First, the vertical cross-sectional profiles are extracted to detect the approximate positions of vein regions in a given finger-vein image. Second, the accurate positions of the vein regions are detected by checking the depth of the vein's profile using various depth thresholds. Third, the quality of the finger-vein image is measured by using the number of detected vein points in relation to the depth thresholds, which allows individual variations of vein density to be considered for quality assessment. Fourth, by assessing the quality of input finger-vein images, inferior-quality images are not used for recognition, thereby enhancing the accuracy of finger-vein recognition. Experiments confirmed that the performance of finger-vein recognition systems that incorporated the proposed quality assessment method was superior to that of previous methods.

Manufacture of Squid-Jeotgal by the Improved Process (개선된 제조기법에 의한 오징어젓갈 제조)

  • YOON Ji-Hye;LEE Won-Dong;KANG Ji-Hee;LEE Ji-Sun;LEE Myung-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.4
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    • pp.333-339
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    • 2003
  • New manufacturing process was applied to manufacture the low salted Squid-Jeotgal to improve the quality variation salty taste and shelf-life. It's optimum salting and sugaring process was made by the addition of $17\%$ NaCl for 3 hr and $15\%$ corn syrup for 4 hr with 10 rpm agitation. Quality variations of Squid-Jeotgal produced by the improved and the conventional process were packed by jar, polyethylene lerephthalatefpolyethyleneilinear low density polyethylene (PET) and low density polyethylene (PE). And then quality variations of them were investigated at storage temperature of 10, 20, and $30^{\circ}C.$ Decreasing rate of pH, increasing rates of VBN and viable cell counts of Squid-Jeotgal produced by the improved process were slower than those of the conventional process at all storage temperature. Sensory evaluation indicated that the production of Squid-Jeotgal by the improved process extended the shelf-life about 10-20 days.

A Study on Particle Filter based on KLD-Resampling for Wireless Patient Tracking

  • Ly-Tu, Nga;Le-Tien, Thuong;Mai, Linh
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.92-102
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    • 2017
  • In this paper, we consider a typical health care system via the help of Wireless Sensor Network (WSN) for wireless patient tracking. The wireless patient tracking module of this system performs localization out of samples of Received Signal Strength (RSS) variations and tracking through a Particle Filter (PF) for WSN assisted by multiple transmit-power information. We propose a modified PF, Kullback-Leibler Distance (KLD)-resampling PF, to ameliorate the effect of RSS variations by generating a sample set near the high-likelihood region for improving the wireless patient tracking. The key idea of this method is to approximate a discrete distribution with an upper bound error on the KLD for reducing both location error and the number of particles used. To determine this bound error, an optimal algorithm is proposed based on the maximum gap error between the proposal and Sampling Important Resampling (SIR) algorithms. By setting up these values, a number of simulations using the health care system's data sets which contains the real RSSI measurements to evaluate the location error in term of various power levels and density nodes for all methods. Finally, we point out the effect of different power levels vs. different density nodes for the wireless patient tracking.

A Study on Geotechnical Properties of Deep-sea Sediments in Clarion-Clipperton Fracture Zone of NE Pacific (북동태평양 클라리온-클리퍼톤 지역 심해저 표층 퇴적물의 지질공학적 특성 연구)

  • Chi, Sang-Bum;Oh, Jae-Kyung;Lee, Hyun-Bok;Kim, Ki-Hyun
    • Ocean and Polar Research
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    • v.25 no.2
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    • pp.133-145
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    • 2003
  • Deep-sea surface sediments were collected using a multiple corer at 20 stations of Clarion-Clipperton fracture zone in the northeast equatorial Pacific to understand latitudinal and longitudinal variations of geotechnical properties. There was a distinct latitudinal variation of geotechnical properties in the study area. The northern sediments showed finer grain size, lower water content and porosity, higher bulk density and specific grain density, lower liquid limits and plastic limits than their southern counterparts. The northern sediments are classified into inorganic clays of low plasticity (fat clays) on plasticity charts and normal to active clay on activity chart, whereas, the southern sediments are classified into fine-grained, highly-plastic, inorganic and biogenic silt or organic clays on plasticity chart and normal to very active clay on activity chart. When shear strength are considered, the northern sediments were found to be in unconsolidated states, while the southern ones to be normal to over-consolidated states. These latitudinal variations in sediment characteristics are likely caused by differences in productivity of surface water that controls sediment compositions, sedimentation rates, and grain solubility.

Copper, aluminum based metallization for display applications (표시소자 응용을 위한 copper, aluminum 박막의 성장과 특성)

  • 김형택;배선기
    • Electrical & Electronic Materials
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    • v.8 no.3
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    • pp.340-351
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    • 1995
  • Electrical, physical and optical properties of Aluminum(Al), Copper(Cu) thin films were investigated in order to establish the optimum sputtering parameters in Liquid Crystal Display (LCD) panel applications. DC-magnetron sputtered film on coming 7059 samples were fabricated with variations of deposition power densities, deposition pressures and substrate temperatures. Low resistivity films(AI;2.80 .mu..ohm.-cm, Cu:1.84 .mu..ohm-cm),which lower than the reported values, were obtained under sputtering parameters of power density(250W), substrate temperature(450-530.deg. C) and 5*10$\^$-3/ Torr deposition pressure. Expected columnar growth and stable grain growth of both films was observed through the Scanning Electron Microscope(SEM) micrographs. Dependency of the applicable defect-free film density upon depositon power and temperature was also characterized. Not too noticable variations in X-ray diffraction patterns were remarked under the alterations of sputtering parameters. High optical reflectivities of Al, Cu films, approximately 70-90 %, showed high degree of surface flatness.

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Variation of Community Structure of Decapods by Season and Depth near Oryuk Islets off Busan, Korea (오륙도 주변해역 십각류의 계절별 수심별 종조성과 군집구조)

  • PARK, Hyun-Jung;PARK, Won-Gyu;CHOI, Jung-Wha;LEE, Bo-Ram
    • Journal of Fisheries and Marine Sciences Education
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    • v.29 no.1
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    • pp.257-269
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    • 2017
  • The occurrence variations of decapods by season and depth off Oryuk Islets, Busan were investigated at seven stations in April and October 2009, July 2010 and January 2011. Decapods were collected by SCUBA diving at 5 m and 10 m depths. 46 species belonging to 18 families in 3 orders were identified. Pilumnus minutus, Pugettia intermedia, Pachycheles stevensii, and Paguristes japonicus were dominant species, comprising 73.0% of total decapods. P. minutus and P. intermedia were abundant in all seasons (except summer) while P. stevensii and P. japonicus were abundant in fall and summer. Dominant species were divided into three groups (resident species, seasonal species and temporary species) on the basis of their occurrence patterns. P. minutus and P. intermedia were resident species while P. stevensii, P. japonicus were temporary species. The species number, density and biomass of decapods were fluctuated by seasons. They were highest in fall and lowest in winter. This study implied that the variations of species number and density of decapods were significantly related with seasonal change of water temperature.