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A Study on the Cultivation of Enteromorpha prolifera(Muller) J.Agardh, Chlorophyta in Korea (녹조식물 가시파래, Enteromorpha prolifera의 양식연구)

  • 윤장택;조용철;공용근
    • Journal of Aquaculture
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    • v.16 no.1
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    • pp.44-50
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    • 2003
  • This study aimed to develop the methods of growing Enteromorpha prolifera natural seedlings in its natural habitat and artificial indoor seedlings by inducing spore release. Likewise, the study examined the possibility of mass production by developing cultivation techniques with cultivating examination. The natural seedling of E.prolifera thrived in a sea area composed of sand and mud, which Is its natural habitat. Growing of this alga on the seedling frame 20 cm high from the bottom at the intertidal zone in summer and 40 cm high in fall was found to be very effective. However, enabling the best attachment rate for artificial indoor seedling requires inducing spore release after drying the mature thalli in a dark place fur about 12∼24 hours and setting seedling nets in a dark water tank (spore solution) for 24 hours. Breeding E.prolifera in a pole-system farm is best done in shallow sea areas with mud or mud and sand geological feature. However, floating-system lam is better for deep-sea areas with fast current. Ideal farming places are sea areas with plenty of nutritional salt and safe places that protect the lam facilities against billows. Furthermore, an exposure method on seawater surface to produce larger output should be used.

Development of Neutaribeosut Varieties (Pleurotus ostreatus) Chongpung, Myongwol

  • Lee, He-Duck;Kim, Hong-Kyu;Kim, Young-Gyun;Han, Kyu-Heng;Min, Kwang-Ho;Jeong, Tae-Wo;Lee, Jae-Jung;Jeon, Tae-Sun;Kim, Duck-wan;Kim, Hun-Sick;Han, Jong-Ku
    • Plant Resources
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    • v.3 no.2
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    • pp.105-109
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    • 2000
  • This study was carried out to find a useful mushroom at Chungnam Agricultural Research And Extention Service. Twenty materials used were collected from domestic and exotic area. These races were compared bontanical characteristics to leading varieties by PCR-RAPD methods. Mycelial growth temperature of Chongpung and Myongwol were at 20 to 25 $^{\circ}C$ and 25 to 30 $^{\circ}C$ at PDA medium, respectively mycelial growth of these varieties were similiar at pH 6.5 to 7.5. In case of mushroom cultivation temperature ranges, Chongpung was at 5 to 26$^{\circ}C$ and Myongwol was at 7 to 28$^{\circ}C$, but the optimum temperature range of these were appeared at 15 to 19$^{\circ}C$. Culture temperature of these was 23$^{\circ}C$ and period of mycelial culture was needed 23 to 24 days under 850cc/pp, while was needed 11 to 12 days at waste cotton medium. Cap color of these at first inducing mushroom was all dark blue, but at late growing stages Chongpung was shown as grey, and Myongwol was shown as dark grey. Yield of Chongpung was appeared as 46kg/3.3$m^2$ and that of Myongwol was 41kg /3.3$m^2$, while Chunchu No2 as check was 40kg/3.3$m^2$. Results from PDA medium and PCR-RAPD analysis two of these were different from others.

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Petrogenesis of the Skarn at the Dielette, Cotentin, France (디엘레트지역(地域) 스카른의 암석학적(岩石學的) 성인연구(成因硏究))

  • Chang, Ho Wan
    • Economic and Environmental Geology
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    • v.18 no.2
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    • pp.139-150
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    • 1985
  • Skarn at the Dielette formed largely in calc-silicate hornfels at the contact with the Flamanville granite. The skarn consists mainly of garnet and pyroxene, and less frequently vesuvianite. Traversing toward calc-silicate hornfels wall rock from a central zone of the skarn, the general sequence of formation of mineral assemblages is: (1) dark brown garnet (2) pale brown garnet-vesuvianite-pyroxene, and (3) pyroxene-prehnite-scapolite-wollastonite envelopes (designated as transition zone) developed between skarn and calc-silicate hornfels. The central zone of the skarn consists mainly of dark brown garnets (garnet I) that contain little or no pyroxene. The pale brown garnet (garnet II) is associated with pyroxene and vesuvianite. The sequence of these garnets results from the zonal growth outward. There is an abrupt discontinuity in composition between garnet I formed in early stage and garnet II in late stage, while each garnet shows relatively uniform composition. At the zone in contact with the granite, the iron contents of garnets decrease toward the marginal zone of the skarn, from an average value of 36 mole % andradite in garnet I to 18 mole % andradite in garnet II. At the zone distant from the granite, the andradite component decreases from 28 mole % in garnet 1 to 19 mole % in garnet II. The variation of the iron contents of pyroxenes is also similar to that of garnets. The sharp discontinuity in composition of garnets and pyroxenes suggests that the skarn of study area was formed by infiltration metasomatic process. The results of the analyses of mineral assemblages of the transition zone by chemical potential diagrams suggest that the transition zone was made by the diffusion of the elements Ca, K and Fe from the skarn to the calc-silicate hornfels contact zone. The estimated temperatures and $Xco_2$ for the formation of the transition zone show $300^{\circ}C$$440^{\circ}C$ and $0.07{\pm}0.05<Xco_2<0.02{\pm}0.01$ at 1 Kb respectively.

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Experimental Verification of Obstacle Avoidance Algorithm ELA Applicable to Rescue Robots (구조로봇에 적합한 장애물 회피 알고리즘 ELA의 실험적 검증)

  • Jeong, Hae-Kwan;Hyun, Kyung-Hak;Kim, Soo-Hyun;Kwak, Yoon-Keun
    • The Journal of Korea Robotics Society
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    • v.4 no.2
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    • pp.105-111
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    • 2009
  • In this paper, we provide experimental results and verification for obstacle avoidance algorithm 'ELA(Emergency Level Around)', which is applicable to rescue robots. ELA is a low level intelligence-based obstacle avoidance algorithm, so can be used in fast mobile robots requiringhigh speed in operation with little computational load. Constructed system for experiments consist of laptop, sensors, peripheral devices and mobile robot platform VSTR(Variable Single-tracked Robot) to realize predetermined scenarios. Finally, experiment was conducted in indoor surroundings including miscellaneous things as well as dark environment to show fitness and robustness of ELA for rescue, and it is shown that VSTR navigates endowed area well with real-time obstacle avoidance based on ELA. Therefore, it is concluded that ELA can be a candidate algorithm to increase mobility of rescue robots in real situation.

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광 경화성 단분자를 이용한 수직 배향 액정 표시 소자의 노광 조건에 따른 표면 안정화의 연구

  • Kim, Hye-Yeong;Kim, Dae-Hyeon;Gwon, Dong-Won;Kim, U-Il;Jo, In-Yeong;Kim, Seong-Min;Lee, Seung-Hui;Jeong, Yeon-Hak;Ryu, Jae-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.187-187
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    • 2009
  • The PVA(patterned vertical alignment) mode has a excellent dark state at normal direction. but they has a disclination area at divided domain region at voltage on state. so this disclination make a slow response time and decrease transmittance. To overcome this problem, we research about polymer stabilized vertical alignment (PS-VA) method which was using the UV curable reactive mesogen. According to our research, UV exposure condition which was UV dosage condition effected to rising time and decay time and also threshold voltage.

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Design and Fabrication of Si pin photodiode for APF optical link (APF optical link용 Si pin photodiode의 설계 및 제작)

  • 강현구;남정식;이지현;김윤희;이상열;김장기;장지근
    • Proceedings of the IEEK Conference
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    • 2000.06b
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    • pp.270-273
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    • 2000
  • We have fabricated and analyzed photodiodes for optical link with Si pin structures. As the results of experiment, the web patterned photodiode(type C) with $p^{+}$-guard ring showed low junction capacitance of 6~7 pF at $V_{R}$=-5V and high separation ability for optical signal(dark current : $\leq$ 5 nA, optical signal current : $\geq$ 340 nA) due to the small effective $p^{+}$-n junction area and the expanded electric field region. The fabricated Si pin photodiode can be applicable for detecting an optical signal with the wavelength of about 660~670 nm. It can also be integrated with the twin well CMOS structure to develope an one chip based optical receiver IC. IC.C.

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Current-Voltage Characterization of Silicon Quantum Dot Solar Cells

  • Kim, Dong-Ho
    • Transactions on Electrical and Electronic Materials
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    • v.10 no.4
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    • pp.143-145
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    • 2009
  • The electrical and photovoltaic properties of single junction silicon quantum dot solar cells are investigated. A prototype solar cell with an effective area of 4.7 $mm^2$ showed an open circuit voltage of 394 mV and short circuit current density of 0.062 $mA/cm^2$. A diode model with series and shunt resistances has been applied to characterize the dark current-voltage data. The photocurrent of the quantum-dot solar cell was found to be strongly dependent on the applied voltage bias, which can be understood by consideration of the conduction mechanism of the activated carriers in the quantum dot imbedded material.

The characteristic study of hybrid X-ray detector using ZnS:Ag phosphor (ZnS:Ag phosphor를 이용한 hybrid 형 X-ray detector 특성 연구)

  • Park, Ji-Koon;Gang, Sang-Sik;Lee, Dong-Gil;Cha, Byeong-Yeol;Nam, Sang-Hee;Choi, Heung-Kook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05b
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    • pp.27-30
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    • 2002
  • Photoconductor for direct detection flat-panel imager present a great materials challenge, since their requirements include high X -ray absorption, ionization and charge collection, low leakage current and large area deposition. Selenium is practical material. But it needs high thickness and high voltage in selenium for high ionization rate. We report comparative studies of detector sensitivity. One is an a-Se with $70{\mu}m$ thickness on glass. The other has hybrid layer of depositting ZnS phosphor with $100{\mu}m$ on a-Se. The leakage current of hybrid is similar to it of a-Se, but photocurrent is lager than a-Se. Both of them have high spatial resolution, but hybrid has higher sensitivity than a-Se at comparable bias voltage.

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Convolution and Deconvolution Algorithms for Large-Volume Cosmological Surveys

  • Park, KeunWoo;Rossi, Graziano
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.50.4-51
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    • 2015
  • Current and planned deep multicolor wide-area cosmological surveys will map in detail the spatial distribution of galaxies and quasars over unprecedented volumes, and provide a number of objects with photometric redshifts more than an order of magnitude bigger than that of spectroscopic redshifts. Photometric information is statistically more significant for studying cosmological evolution, dark energy, and the expansion history of the universe at a fraction of the cost of a full spectroscopic survey, but intrinsically carries a bias due to noise in the distance estimates. We provide convolution- and deconvolution-based algorithms capable of removing this bias -- thus able to exploit the full cosmological information -- in order to reconstruct intrinsic distributions and correlations between distance-dependent quantities. We then show some direct applications of our techniques to the VIMOS Public Extragalactic Redshift Survey (VIPERS) and the Sloan Digital Sky Survey (SDSS) datasets. Our methods impact a broader range of studies, when at least one distance-dependent quantity is involved; hence, they will be useful for upcoming large-volume surveys, some of which will only have photometric information.

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Implementation of Nose and Face Detections in Depth Image

  • Kim, Heung-jun;Lee, Dong-seok;Kwon, Soon-kak
    • Journal of Multimedia Information System
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    • v.4 no.1
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    • pp.43-50
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    • 2017
  • In this paper, we propose a method which detects the nose and face of certain human by using the depth image. The proposed method has advantages of the low computational complexity and the high accuracy even in dark environment. Also, the detection accuracy of nose and face does not change in various postures. The proposed method first locates the locally protruding part from the depth image of the human body captured through the depth camera, and then confirms the nose through the depth characteristic of the nose and surrounding pixels. After finding the correct pixel of the nose, we determine the region of interest centered on the nose. In this case, the size of the region of interest is variable depending on the depth value of the nose. Then, face region can be found by performing binarization using the depth histogram in the region of interest. The proposed method can detect the nose and the face accurately regardless of the pose or the illumination of the captured area.