• Title/Summary/Keyword: scale formation

Search Result 1,222, Processing Time 0.028 seconds

Effect of Light and Scale Explant Conditions on Propagation Efficiency in Lilium callosum Scale Culture (땅나리 기내 인편 배양시 광환경과 배양 절편체의 조건이 증식 효율성에 미치는 영향)

  • Park, Ji Young;Yoo, Yong Kweon;Jeong, Jeong Hag;Kim, Ki Sun
    • Horticultural Science & Technology
    • /
    • v.16 no.3
    • /
    • pp.358-360
    • /
    • 1998
  • Series of in vitro experiments in Lilium callosum were conducted to investigate efficient multiplication through finding the optimal cultural environment, and organogenic capability of cultural explants, and then to determine the progressive method for enhancing bulblet growth in Lilium callosum scale culture. Twenty-four hr photoperiod was most effective for the growth of bulblet and the formation of other organs. Optimum light intensity for bulblet growth was 2,500~5,000 Lux. When bulbets were subcultured, growth of bulblets were enhanced by removing excessive leaf blade. Number of bulblets per scale increased as mother scale size increased, whereas diameter of bulblet from the small size mother scale increased. Bulblet formation and development was induced when explants were placed above the medium to be exposed to more light.

  • PDF

A Study on the Cause of Scale Formation in Biogas Plant with Food Wastewater (음식물류 폐수를 이용한 바이오가스 생산시설의 스케일 형성요인에 관한 연구)

  • Bae, Young-Shin;Chun, Seung-Kyu
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.35 no.9
    • /
    • pp.660-665
    • /
    • 2013
  • To find out the major cause of scale formation in digestion facility, a componential analysis of scale and a digestion experiment for food wastewater were conducted. The analysis indicated that grease in food wastewater was closely connected to the organic component of scale. It is also indicated that grease-removed food wastewater showed 58.9% level compared to unprocessed one in crystal generation quantity in this study. The experiment provided insight that grease is one of the important causes of scale formation. Additionally, pre-removal of grease from food wastewater did not show negative effect on digestion gas production, as 68.7 L-gas/kg-COD for grease-removed food wastewater and 67.7 L-gas/kg-COD for unprocessed one.

A VARIATION IN THE PRESENT STAR FORMATION ACTIVITY OF SPIRAL GALAXIES

  • TOMITA AKIHIKO;TOMITA YOSHIO;SAITO MAMORU
    • Journal of The Korean Astronomical Society
    • /
    • v.29 no.spc1
    • /
    • pp.71-72
    • /
    • 1996
  • We show that the star formation activity of spiral galaxies has a great variety. The star formation variation in a time scale of $10^8$ yr and the mechanism responsible for the variation are discussed.

  • PDF

New occurrence of Cupressinocladus sp. from the Lower Cretaceous Jinju Formation, Shindong Group, Korea

  • Kim, Jong-Heon
    • Journal of the Korean earth science society
    • /
    • v.30 no.5
    • /
    • pp.605-610
    • /
    • 2009
  • Cupressinocladus sp. found from the upper part of the Jinju Formation of the Shindong Group, Korea is described here based on the newly found leafy shoots. This species is characterized by the branched leafy shoot with decussate scale leaves. The presence of Cupressinocladus in the Jinju Formation indicates that the Early Cretaceous flora-sites in Eastern Eurasia are in a close association with territories of the mixed-type floras. The finding of this species records the first report for the Nakdong flora.

Formation of star clusters by cloud-cloud collision

  • Han, Daniel;Kimm, Taysun
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.44 no.2
    • /
    • pp.68.3-68.3
    • /
    • 2019
  • We present the preliminary results on the formation of star clusters by cloud-cloud collision. For this purpose, we perform sub-parsec scale, radiation-hydrodynamic simulations of giant molecular clouds using a sink particle algorithm. The simulations include photo-ionization, direct radiation pressure, and non-thermal radiation pressure from infrared and Lyman alpha photons. We confirm that radiation feedback from massive stars suppresses accretion onto sink particles. We examine the collision-induced star formation and discuss the possibility on the formation of a globular cluster.

  • PDF

Formation Temperature Dependence of Thermal Stability of Nickel Silicide with Ni-V Alloy for Nano-scale MOSFETs

  • Tuya, A.;Oh, S.Y.;Yun, J.G.;Kim, Y.J.;Lee, W.J.;Ji, H.H.;Zhang, Y.Y.;Zhong, Z.;Lee, H.D.
    • Proceedings of the IEEK Conference
    • /
    • 2005.11a
    • /
    • pp.611-614
    • /
    • 2005
  • In this paper, investigated is the relationship between the formation temperature and the thermal stability of Ni silicide formed with Ni-V (Nickel Vanadium) alloy target. The sheet resistance after the formation of Ni silicide with the Ni-V showed stable characteristic up to RTP temperature of $700\;^{\circ}C$ while degradation of sheet resistance started at that temperature in case of pure-Ni. Moreover, the Ni silicide with Ni-V indicated more thermally stable characteristic after the post-silicidation annealing. It is further found that the thermal robustness of Ni silicide with Ni-V was highly dependent on the formation temperature. With the increased silicidation temperature (around $700\;^{\circ}C$), the more thermally stable Ni silicide was formed than that of low temperature case using the Ni-V.

  • PDF

The Effect of Hair Style for Impression Formation (Hair Style이 인상형성(印象形成)에 미치는 영향(影響))

  • Yoon, So-Young;Yoo, Tai-Soon
    • Journal of Fashion Business
    • /
    • v.5 no.3
    • /
    • pp.73-84
    • /
    • 2001
  • The purpose of this study is to apply fundamental data of impression formation research by analysing and observing the various facial image that can be effected from hair style as well as be helpful for choosing suitable hair style for T.P.O in modern society. This study targeted 305 college women in Daegu and Gyung-book area. Hair Style Image Scale(HSIS)was used the scale of seven point modified the S-D(Semantic Differential) method. The analysis of impression formation effect of hair style using SPSS WIN package have completed from the principal component analysis by Varimax perpendicular rotation method and ANOVA was used to recognize the difference in impression formation according to hair style change. In the case of statistical difference was appeared, LSD post-verification was applied for that. The conclusions of this study is as followed ; 1. The factors of impression formation effected by hair style were classified as goodwill factor, refinement factor, elegance factor and individuality factor. 2. In terms of goodwill factor, long hair style showed highest level and short cut hair, bobbed hair in an order. In refinement factor, there was no difference between short cut hair and bobbed hair and both of them was higher than long hair. In elegance factor, long hair was highest and bobbed hair was lowest. In individuality factor, short cut hair and bobbed hair higher than long hair and no difference between short cut hair and bobbed hair.

  • PDF

Effect of Basis Weight of Handsheet and Machine Made Sheet on Formation (평량에 따른 수초지와 기계지의 지합 특성)

  • Youn, Hye-Jung;Chin, Seong-Min
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.38 no.4 s.117
    • /
    • pp.24-30
    • /
    • 2006
  • Formation which is an indicator of nonuniformity in fiber distribution is concerned with small scale variation in roughness, optical properties, print density, and so on. This study evaluated the formation of sheets which were made usning handsheet former and paper-machine with hydraulic headbox. Optical method and ${\beta}-ray$ method were used for formation test. The fiber type, freeness and basis weight of sheet were considered as variables. The formation of handsheet was affected by fiber type and freeness, and floe size distribution was influenced by basis weight. For machine made sheet, its formation seemed to be dependent on the hydraulic forces in headbox and former. When two formation test methods were compared, there was the highest relationship between optical formation index and normalized standard deviation from ${\beta}-ray$ method.

The Effects of Scale Growth Inhibition on Water Pipe using Frequency Driver (Frequency Driver를 이용한 냉온수관의 스케일 방지억제효과)

  • Jang, Mi-Jeong;Sung, Il-Wha
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.33 no.4
    • /
    • pp.258-266
    • /
    • 2011
  • Scale induced by hardness materials in water must be controled because of it can be result in remarkable damages of pipeline as well as water quality deterioration. Especially hot water system is one of scale management required facility as scale formation can be accelerated by temperature. The scale control performance of frequency driver (FD) was tested instead of existing methods such as chemical, physical and electromagnetic methods which needs chemicals and electric power. Three kinds of pipe coupons were submerged in test water with 500 mg/L of hardness for 33 days and XRD and SEM were analysed for comparing scale formation characteristics of these coupons. Calcite ($CaCO_3$) which came from hardness of water was formed on only cast iron pipe coupon and this coupon showed higher corrosion rate than copper and stainless steel pipe coupon. Hot water circulating system connected cast iron pipe with and without FD was operated with 300 mg/L of hardness water at $50^{\circ}C$ for monitoring of scale formation and water quality with and without FD. XRD showed that FD leaded to magnetite ($Fe_3O_4$) scale which is good scale for preventing corrosion than calcite and SEM image also indicated the scale control effect of FD. Scales of 16% on pipe joint, 14% on pipe length, and 42% on heat exchanger decreased with FD comparing scales of those parts without FD. From the results of water quality, FD reduced crystallization of hardness material without chemical reaction in water and it can indicate that FD is safe and proenvironmental technology for scale reduction.

The Horizon Run 5 Cosmological Hydrodynamical Simulation: Probing Galaxy Formation from Kilo- to Giga-parsec Scales

  • Lee, Jaehyun;Shin, Jihey;Snaith, Owain N.;Kim, Yonghwi;Few, C. Gareth;Devriendt, Julien;Dubois, Yohan;Cox, Leah M.;Hong, Sungwook E.;Kwon, Oh-Kyoung;Park, Chan;Pichon, Christophe;Kim, Juhan;Gibson, Brad K.;Park, Changbom
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.45 no.1
    • /
    • pp.38.2-38.2
    • /
    • 2020
  • Horizon Run 5 (HR5) is a cosmological hydrodynamical simulation which captures the properties of the Universe on a Gpc scale while achieving a resolution of 1 kpc. This enormous dynamic range allows us to simultaneously capture the physics of the cosmic web on very large scales and account for the formation and evolution of dwarf galaxies on much smaller scales. Inside the simulation box. we zoom-in on a high-resolution cuboid region with a volume of 1049 × 114 × 114 Mpc3. The subgrid physics chosen to model galaxy formation includes radiative heating/cooling, reionization, star formation, supernova feedback, chemical evolution tracking the enrichment of oxygen and iron, the growth of supermassive black holes and feedback from active galactic nuclei (AGN) in the form of a dual jet-heating mode. For this simulation we implemented a hybrid MPI-OpenMP version of the RAMSES code, specifically targeted for modern many-core many thread parallel architectures. For the post-processing, we extended the Friends-of-Friend (FoF) algorithm and developed a new galaxy finder to analyse the large outputs of HR5. The simulation successfully reproduces many observations, such as the cosmic star formation history, connectivity of galaxy distribution and stellar mass functions. The simulation also indicates that hydrodynamical effects on small scales impact galaxy clustering up to very large scales near and beyond the baryonic acoustic oscillation (BAO) scale. Hence, caution should be taken when using that scale as a cosmic standard ruler: one needs to carefully understand the corresponding biases. The simulation is expected to be an invaluable asset for the interpretation of upcoming deep surveys of the Universe.

  • PDF