• Title/Summary/Keyword: 산란 특성

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Growth Variation among the Different Populations of Sea Urchin, Pseudocentrotus depressus (분흥성게의 지역별 개체군 성장에 관한 연구)

  • CHUNG Sang-Chul;NATSUKARI Yutaka
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.4
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    • pp.421-427
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    • 1995
  • To know the variation in the growth of the sea urchin, Pseudocentrotus depressus according to their localities, three different populations including the culture populations, the released populations, and the wild populations were investigated using the cluster analysis. For this purpose, pigment banding pattern on the genital plate was used as an age character. The population composed of the same year class was born between September 25th and October 5th every year. The population of 9 to 10 months old had no $r_1,\;whereas\;r_1$, was observed in the population of either 1 year and 10 or 11 months old, and both $r_1,\;and\;r_2$ in the population of either 2 year and 9 or 10 months old. Therefore, $r_1,\;and\;r_2$ radius were regarded as an annual ring. Growth in the culture populations was much better than that In either the released or the wild populations. However, when the cultured populations composed of 8 to 12 mm in test diameter was released to the shove near a culture farm, its growth appeared to be similar to that of the wild Populations. The wide distribution patterns of test diameter measured from the same year class of both the cultured and the wild populations were probably due to either long spawning period or growth differences between individuals. Except Yamaguchi and Cheju populations, the move closely located populations showed the more similar growth pattern. However, the growth of Cheju population appeared to be similar to that of Aba, Mogi, Toishi rather than Kasiwazima although Cheju Island was more closely located with Kasiwazima than other localities. In addition, the population of Yamaguchi, located at the highest latitute, revealed the similar growth pattern to that of Nomozaki, located at the lowest latitute.

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Distribution and Migration of Flying Squid, Ommastrephes bartrami (LeSueur), in the North Pacific (북태평양에 있어서 빨강오징어 Ommastrephes bartrami (LeSueur)의 분포 및 회유)

  • GONG Yeong;KIM Yeong Seung;KIM Soon Song
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.166-179
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    • 1985
  • The seasonal distribution and migration of flying squid, Ommastrephes bartrami (LeSueur), in the North Pacific were studied by means of mantle length, surface temperature, and catch and effort data of the Korean drift gillnet fishery from 1980 to 1983. The water temperature for the best fishing ranged from $15^{\circ}\;to\;16^{\circ}C$ in May through July and from $13^{\circ}\;to\;18^{\circ}C$ in August through January. High densities of flying squid were found in the thermal fronts with $18^{\circ}C$ isotherm in August and with $15^{\circ}C$ isotherm in September. The densities of flying squid were higher in the western region than in the eastern region in the North Pacific. The high densities of flying squid in the northwestern Pacific were attributed to the high gradients of oceanographic properties in the region. Migration models for flying squid were hypothesized based on the monthly distributions of catch per unit net, mantle length compositions by statistical blocks, and the hydrographic features of the North Pacific. The large flying squid moved to the northern region and to the central Pacific region earlier than the small sized group in the northward migration period (from June to August). Flying squid begin the reverse southward migration from the Subarctic Frontal Zone in autumn with onset of cooling and the development of Oyashio Current. The large sized group starts their southward return migration from more northern waters than the small sized group but the former moves past the later ana reaches the spawing ground first.

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Studies on the Management Plan in Urban Ecological Protected Area of Seoul - A Case Study of the Baeksil Valley Ecological Scenery and Conservation Area - (서울 도시생태 보호지역 관리계획 연구 - 백사실계곡 생태·경관보전지역을 대상으로 -)

  • Park, Seok-Cheol;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.6
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    • pp.109-126
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    • 2015
  • This study is for constructing detailed data to secure biological diversity and maintain a healthy ecosystem in Backsasil Valley Ecological and Scenery Conservation Area, and for preparing an ecological management plan fit for the protected area. The period for this study was from April 2010 to May 2013. Recently, the increase of visitors to Baeksasil Valley, as well as the plantation and dissemination of introduced vegetable species, become factors accelerating ecological disturbance. Major research contents included the reviews of the management system of the protected areas, the necessity of ecological management at the basin level, establishing the system of a management plan, research and analysis of environment ecology, analysis of threatening factors, goal-setting, management strategies, and a plan through SWOT analysis. Survey items were the natural environment, major components of ecosystem, and human-use. The goals of ecological management were basin zone management for amphibians, conservation and restoration of forest vegetation for conservation habitat of Dryocopus martius, conservation habitat of Zelkova serrta for nature landscape, and management of users for environment protection. The conservation management plan at a basin zone level contains the management of point and non-point pollution sources in the upstream, securing growing conditions for native plants, securing safe habitats for amphibians, and securing of habitats for major wild birds. Also, restoration of natural forests, management of native plants and introduced vegetable species, and restoration of degraded forest paths are suggested for the restoration plans.

Analysis on the EMC evaluating method for applying wireless communications in NPP (원전 내 무선통신 적용에 대한 전자파 적합성 평가방법 분석)

  • Kang, SeungSeok;Lim, Tae Heung;Choo, Jaeyul;Kim, HyungTae;Kim, DaeHee;Byun, Gangil;Park, Jong Eon;Lee, Jun-Yong;Choo, Hosung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.12
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    • pp.2221-2231
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    • 2017
  • In this paper, we surveyed previous cases, network protocols (such as Wi-Fi, Zigbee, Z-wave, and WirelessHart) and propagation characteristics on the application of maintaining equipments for instrumentation and control (I&C) using wireless communication techniques inside the nuclear power plant (NPP). In addition, we compared and analyzed the difference of detailed regulations with respect to the electromagnetic interference (EMI) and radio frequency interference (RFI) in the Regulatory Guide 1.180 rev. 1 (RG. 1.180) for adopting the wireless communication techniques inside the NPP, and other regulations, such as MIL-STD 461E and IEC 61000-4, that are recognized in the KINS/RG-N03.09 (Rev. 2). Furthermore, we investigated evaluating factors about electromagnetic properties by considering indoor environments, wave scattering, shielding effectiveness, and the indoor wave attenuation model that were not included in the current electromagnetic compatibility regulation.

A Study of Skin Reflectance Using Kubelka-Munk Model (Kubelka-Munk 모델을 이용한 피부 분광반사율 연구)

  • Cho, A Ra;Kim, Su Ji;Lee, Jun Bae;Sim, Geon Young;Back, Min;Cho, Eun Seul;Jang, Ji Hui;Jang, Eunseon;Kim, Youn Joon;Yoo, Kweon Jong;Han, Jeong Woo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.1
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    • pp.45-55
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    • 2016
  • Light shows various optical behaviors such as reflection, absorption, and scattering on skin for individuals. In particular, reflection of light from the skin has been widely used as the brightness index of the skin of individuals through the measurement of the physical quantity of spectral reflectance. Therefore, the study of light behavior on skin would be useful for the preparation of new evaluation method in the development stage of make-up products. In this study, multi-dimensional analysis for spectral reflectance behavior of light on individual skin was performed using Kubelka-Munk model. Also, we analyzed the contribution of skin parameters such as skin thickness and hemoglobin, which could affect the spectral reflectance, using above model and literature information. Base on this, we calculated the theoretical reflectance of normal women for visual light, which showed good agreement with the measured reflectance. Our study of light propagation in skin based on Kubelka-Munk model provides useful insight for the development of personalized cosmetic in the near future.

Retrieval of Vertical Single-scattering albedo of Asian dust using Multi-wavelength Raman Lidar System (다파장 라만 라이다 시스템을 이용한 고도별 황사의 단산란 알베도 산출)

  • Noh, Youngmin;Lee, Chulkyu;Kim, Kwanchul;Shin, Sungkyun;Shin, Dongho;Choi, Sungchul
    • Korean Journal of Remote Sensing
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    • v.29 no.4
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    • pp.415-421
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    • 2013
  • A new approach to retrieve the single-scattering albedo (SSA) of Asian dust plume, mixed with pollution particles, using multi-wavelength Raman lidar system was suggested in this study. Asian dust plume was separated as dust and non-dust particle (i.e. spherical particle) by the particle depolarization ratio at 532 nm. The vertical profiles of optical properties (the particle extinction coefficient at 355 and 532 nm and backscatter coefficient at 355, 532 and 1064 nm) for non-dust particle were used as input parameter for the inversion algorithm. The inversion algorithm provides the vertical distribution of microphysical properties of non-dust particle only so that the estimation of the SSA for the Asian dust in mixing state was suggested in this study. In order to estimate the SSA for the mixed Asian dust, we combined the SSA of non-dust particles retrieved by the inversion algorithms with assumed the SSA of 0.96 at 532 nm for dust. The retrieved SSA of Asian dust plume by lidar data was compared with the Aerosol Robotics Network (AERONET) retrieved values and showed good agreement.

Band-Gap Energy and Thermoelectric Properties of 90% $Bi_2Te_3-10% Bi_2Se_3$ Single Crystals (90% $Bi_2Te_3-10% Bi_2Se_3$ 단결정의 밴드갭 에너지와 열전특성)

  • Ha, Heon-Pil;Hyeon, Do-Bin;Hwang, Jong-Seung;O, Tae-Seong
    • Korean Journal of Materials Research
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    • v.9 no.4
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    • pp.349-354
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    • 1999
  • The temperature dependences of the Hall coefficient, carrier mobility, electrical resistivity, Seebeck coefficient, thermal conductivity, and figure-of-merit of the undoped and $CdI_2$-doped 90% $Bi_2Te_3-10% Bi_2Se_3$, single crystals, grown by the Bridgman method, have been characterized at temperatures ranging from 77K to 600K. The saturated carrier concentration and degenerate temperature of the undoped 90% $Bi_2Te_3-10% Bi_2Se_3$ single crystal are $5.85\times10_{18}cm^{-3}$ and 127K, respectively. The scattering parameter of the 90% $Bi_2Te_3-10% Bi_2Se_3$ single crystal is determined to b -0.23, and the electron mobility to hole mobility ratio ($\mu_e/\mu_h)$ is 1.45. The bandgap energy at 0K of the 90% <$Bi_2Te_3-10% Bi_2Se_3$ single crystal is 0.200 eV. Adding $CdI_2$as a donor dopant, a maximum figure-of-merit of $3.2\times10^{-3}/K$$CdI_2$-doped specimen.

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Properties of Au Clusters Supported on $TiO_2$ Studied by XPS, ISS, AES, and TPD (XPS, ISS, AES, TPD를 이용한 $TiO_2$ 위에 지지된 Au 클러스터의 특성 연구)

  • Kim, Dae Young
    • Journal of the Korean Chemical Society
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    • v.42 no.6
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    • pp.607-617
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    • 1998
  • Au was dosed on $TiO_2(001)$ film grown epitaxially on Mo(100) surface in about 90 ${\AA}$ thickness. The growth mode of Au, thermal behavior and stability of the Au clusters, and the binding energy shift of Au 4f with the change in the amount of Au loading were studied by Auger Electron Spectroscopy (AES), Temperature Programmed Desorption (TPD) spectroscopy, Ion Scattering Spectroscopy (ISS), and X-ray Photoelectron Spectroscopy (XPS). Au grows three dimensionally on $TiO_2(001)$ film and the average size of Au clusters prepared at low temperature is smaller than those at higher temperature and the size increases with temperature irreversibly. Au clusters on $TiO_2(001)/Mo(100)$ start evaporation at 1000 K. TPD spectra of Au show very asymmetric peaks with the same leading edges irrespective of the amount of Au loading. The temperature at the peak maximum increases with the amount of Au. The desorption energy of Au obtained from the leading edge analysis of the TPD spectra is about 50 kcal/mol. The initial sticking coefficient of Au on $TiO_2(001)$ is constant in the temperature range of 200-600 K. The binding energy of Au 4f for the Au loaded on the film less than 2.0 MLE shifts to higher energy compared with the bulk Au. The shift is +0.3 eV at 0.1 MLE Au amount.

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Vertical Distribution of Eggs and Larvae of Maurolicus muelleri in the Southeastern Waters of Korea (한국 동해남부해역 앨퉁이 난.자어의 연직분포)

  • Kim, Jin-Yeong;Kang, Young-Shil
    • Korean Journal of Ichthyology
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    • v.7 no.1
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    • pp.64-70
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    • 1995
  • Vertical distribution of eggs and larvae of Maurolicus muelleri were studied in the south-eastern waters of Korea during 1985 and 1986. Samples were collected vertically at three different layers, 0~30 m, 30~50m and 50~100m. The densities of egg and larva were high in August. Eggs and zooplankton were abundant around the thermocline in the temperature range of $10{\sim}15^{\circ}C$ at the layers of 50 m depth in 1985, and 30~100m depth in 1986. Eggs in the cleavage stage were abundant at the layer of 50~100m depth, while those of processing embryonic body formation were tended to concentrate at the layer of 30~50m depth. The vertical distribution of each developmental stage differed according to sampling time. They were distributed uniformly at water column from 30 m to 100m depth in the midnight, but concentrated at the layer from 30 m to 50 m from dawn to sunset. Before and after midnight, eggs in the cleavage stage were most abundant. It was assumed that M. muelleri spawned at the layer of 50~100m depth around the midnight, and the eggs ascended to the layer of 30~50m depth with development.

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Ultrasonic Wave Propagation Analysis for Damage Detection in Heterogeneous Concrete Materials (콘크리트 내부결함 탐지를 위한 초음파 전파 해석)

  • Jung, Hwee Kwon;Rhee, Inkyu;Kim, Jae-Min
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.33 no.4
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    • pp.225-235
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    • 2020
  • Ultrasonic investigation of damage detection has been widely used for non-destructive testing of various concrete structures. This study focuses on damage detection analysis with the aid of wave propagation in two-phase composite concrete with aggregate (inclusion) and mortar (matrix). To fabricate a realistic simulation model containing a variety of irregular aggregate shapes, the mesh generation technique using an image processing technique was proposed. Initially, the domains and boundaries of the aggregates were extracted from the digital image of a typical concrete cut-section. This enables two different domains: aggregates and mortar in heterogeneous concrete sections, and applied the grids onto these domains to discretize the model. Subsequently, finite element meshes are generated in terms of spatial and temporal requirements of the model size. For improved analysis results, all meshes are designed to be quadrilateral type, and an additional process is conducted to improve the mesh quality. With this simulation model, wave propagation analyses were conducted with a central frequency of 75 kHz of the Mexican hat incident wave. Several void damages, such as needle-shaped cracks and void-shaped holes, were artificially introduced in the model. Finally, various formats of internal damage were detected by implementing energy mapping based signal processing.