• Title/Summary/Keyword: length-width ratio

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Efficiency of Model Oil Fences for One Vessel Using a Physical Experiment and Numerical Calculation (모형 실험과 수치 해석을 통한 단선용 모형 오일펜스의 성능 해석)

  • Kim, Tae-Ho;Jang, Duck-Jong;Yang, Kyung-Uk;Na, Sun-Chol;Kim, Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.2
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    • pp.140-149
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    • 2008
  • This study evaluated the efficiency of an oil fence and spreading devices for one vessel in a towing tank. A series of model experiments and numerical calculations were conducted using an existing oil fence for two vessels and a new method for one vessel. Models of the oil fence and spreading devices were constructed on $1/20^{th}$ scale from waterproofed nylon fabric and canvas. The tensions acting on the model of the oil fences and the horizontal distance between the spreading devices were calculated numerically while the oil fences were being towed. The results were extremely close to the results of the model experiments. The ratio of the opening width to the total length of the oil fence, which shows the efficiency of the oil fence for one vessel, was 49.7% in 0.4 m/sec. Therefore, the proposed oil fence system should be very useful for oil containment at sea. As the opening width of the oil fence is not proportional to the length of the towing rope, it may be reasonable to maintain the towing rope at approximately 100 m. Furthermore, a reasonable towing speed, when operating the oil fence for one vessel equipped with spreading devices, was within 0.4 m/sec.

Characterization of length and width of poly-silicon thin film transistors (TFT의 길이와 두께에 관한 특성)

  • Lee, Jeoung-In;Hwang, Sung-Hyun;Jung, Sung-Wook;Jang, Kyung-Soo;Lee, Kwang-Soo;Chung, Ho-Kyoon;Choi, Byoung-Deog;Lee, Ki-Yong;Yi, Jun-Sin
    • Proceedings of the KIEE Conference
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    • 2006.10a
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    • pp.121-122
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    • 2006
  • Recently, poly-Si TFT-LCD starts to be mass produced using excimer laser annealing (ELA) poly-Si. The main reason for this is the good quality poly-Si and large area uniformity. We report the influence of channel length and width on poly-Si TITs performance. Transfer characteristics of n-channel poly-Si thin film transistors fabricated on polycrystalline silicon (poly-Si) thin film transistors (TFTs) with various channel lengths and widths of $2-30{\mu}m$ has been investigated. In this paper, we analyzed the data of n-type TFTs. We studied threshold voltage ($V_{TH}$), on/off current ratio ($I_{ON}/I_{OFF}$), saturation current (I_{DSAT}$), and transconductance ($g_m$) of n-channel poly-Si thin film transistors with various channel lengths and widths.

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Open-jet boundary-layer processes for aerodynamic testing of low-rise buildings

  • Gol-Zaroudi, Hamzeh;Aly, Aly-Mousaad
    • Wind and Structures
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    • v.25 no.3
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    • pp.233-259
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    • 2017
  • Investigations on simulated near-surface atmospheric boundary layer (ABL) in an open-jet facility are carried out by conducting experimental tests on small-scale models of low-rise buildings. The objectives of the current study are: (1) to determine the optimal location of test buildings from the exit of the open-jet facility, and (2) to investigate the scale effect on the aerodynamic pressure characteristics. Based on the results, the newly built open-jet facility is well capable of producing mean wind speed and turbulence profiles representing open-terrain conditions. The results show that the proximity of the test model to the open-jet governs the length of the separation bubble as well as the peak roof pressures. However, test models placed at a horizontal distance of 2.5H (H is height of the wind field) from the exit of the open-jet, with a width that is half the width of the wind field and a length of 1H, have consistent mean and peak pressure coefficients when compared with available results from wind tunnel testing. In addition, testing models with as large as 16% blockage ratio is feasible within the open-jet facility. This reveals the importance of open-jet facilities as a robust tool to alleviate the scale restrictions involved in physical investigations of flow pattern around civil engineering structures. The results and findings of this study are useful for putting forward recommendations and guidelines for testing protocols at open-jet facilities, eventually helping the progress of enhanced standard provisions on the design of low-rise buildings for wind.

Effect of Low Temperature and Hot-Water Treatment on Germinatino of Seeds in Dendropanax morbifera $L_{EV}$. (저온 및 온탕 침지가 황칠나무 종자의 발아에 미치는 영향)

  • 최성규
    • Korean Journal of Plant Resources
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    • v.11 no.1
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    • pp.101-105
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    • 1998
  • This study was carried out to find out the method of increasing seed germination rate of Dendropanax morbifera LEV. was drupaceous fruit. The length and width of ovarywas 7.8 to 10.7mm, 6.9 to 9.0mm, respectively, and the shape was elliptical. The ovary had 5 loculi with one speed per loculus , but one seed among 5 weeds was exalbuminous seed. The length and width of seed was 6.3 to 7.4mm, 2.0 to2.mm, respectively, and 1,000 seed weight was 14.3 to 18.0g. Seeding after stroring at $10^{\circ}C$ for 60 to 90 days was germinated to 87% . However, fall seeding directly after harvest was increased to 85% at hot-water treatement ($40^{\circ}C$) for 90 to 120 minute.

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The Fabrication of a-Si:H TFT Improving Parasitic Capacitance of Source-Drain (소오스-드레인 기생용량을 개선한 박막트랜지스터 제조공정)

  • 허창우
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.4
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    • pp.821-825
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    • 2004
  • The a-Si:H TFTs decreasing parasitic capacitance of source-drain is fabricated on glass. The structure of a-Si:H TFTs is inverted staggered. The gate electrode is formed by patterning with length of 8 ${\mu}m∼16 ${\mu}m. and width of 80∼200 ${\mu}m after depositing with gate electrode (Cr) 1500 under coming 7059 glass substrate. We have fabricated a-SiN:H, conductor, etch-stopper and photoresistor on gate electrode in sequence, respectively. The thickness of these thin films is formed with a-SiN:H (2000 ), a-Si:H(2000 ) and n+a-Si:H (500). We have deposited n+a-Si:H ,NPR(Negative Photo Resister) layer after forming pattern of Cr gate electrode by etch-stopper pattern. The NPR layer by inverting pattern of upper gate electrode is patterned and the n+a-Si:H layer is etched by the NPR pattern. The NPR layer is removed. After Cr layer is deposited and patterned, the source-drain electrode is formed. The a-Si:H TFTs decreasing parasitic capacitance of source-drain has channel length of 8 ~20 ${\mu}m and channel width of 80∼200 ${\mu}m. And it shows drain current of 8 ${\mu}A at 20 gate voltages, Ion/Ioff ratio of 108 and Vth of 4 volts.

Stemphylium Leaf Blight of Garlic (Allium sativum) in Spain: Taxonomy and In Vitro Fungicide Response

  • Galvez, Laura;Gil-Serna, Jessica;Garcia, Marta;Iglesias, Concepcion;Palmero, Daniel
    • The Plant Pathology Journal
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    • v.32 no.5
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    • pp.388-395
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    • 2016
  • The most serious aerial disease of garlic is leaf blight caused by Stemphylium spp. Geographical variation in the causal agent of this disease is indicated. Stemphylium vesicarium has been reported in Spain, whereas S. solani is the most prevalent species recorded in China. In this study, Stemphylium isolates were obtained from symptomatic garlic plants sampled from the main Spanish production areas. Sequence data for the ITS1-5.8S-ITS2 region enabled assignation of the isolates to the Pleospora herbarum complex and clearly distinguished the isolates from S. solani. Conidial morphology of the isolates corresponded to that of S. vesicarium and clearly discriminated them from S. alfalfae and S. herbarum on the basis of the size and septation pattern of mature conidia. Conidial morphology as well as conidial length, width and length:width ratio also allowed the Spanish isolates to be distinguished from S. botryosum and S. herbarum. Control of leaf blight of garlic is not well established. Few studies are available regarding the effectiveness of chemical treatments to reduce Stemphylium spp. incidence on garlic. The effectiveness of nine fungicides of different chemical groups to reduce Stemphylium mycelial growth in vitro was tested. Boscalid + pyraclostrobin (group name, succinate dehydrogenase inhibitors + quinone outside inhibitors), iprodione (dicar-boximide), and prochloraz (demethylation inhibitors) were highly effective at reducing mycelial growth in S. vesicarium with $EC_{50}$ values less than 5 ppm. In general, the effectiveness of the fungicide was enhanced with increasing dosage.

Growth Characteristics and DPPH Radical Scavenging Activity of Lettuce 'Fidel' in Plant Factory Using Activated Mineral Groups and Light-emitting Diode Lights

  • Song, Tae-Eui;Park, Seong-Jik;Moon, Joon-Kwan;Kim, In Soo;Lee, Chang Hee
    • Korean Journal of Plant Resources
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    • v.32 no.3
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    • pp.228-236
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    • 2019
  • This study is conducted to investigate the effects of growth characteristics (GC) and DPPH radical scavenging activity (DRSA) of the heading lettuce 'Fidel' depending on four concentrations of activated mineral groups (AMG: 1.6% active minerals and 0.03% CaO) added to basic nutrient solutions (diluted by 0, 0.05, 0.1, and 0.2%) and on four different light-emitting diodes (LED; B:R:W ratio = 0:1:12, 0:1:9, 0:5:5, and 2:3:5). Both 0.1 and 0.2% AMG showed better GC of lettuce in plant width, plant length, leaf width, leaf length, and the number of leaves than those of other AMG, while leaf thickness and chlorophyll value did not show significant difference among all AMG. Moreover, 0.1 and 0.2% AMG showed heavier shoot fresh weights than those of other AMG. As for the combinations of AMG and LED, B0:R5:W5 showed the best lettuce GC regardless of AMG compared to other AMG and LED combinations. As shown in the above results of LED, although there was a difference in lettuce growth by LED, the differences of lettuce growth by AMG were statistically significant. The DRSA was the highest at 82.8% in B2:R3:W5, followed by B0:R5:W5 at 77.8%. LED showed differences but AMG did not affect DRSA. Therefore, the optimal conditions in plant factory for GC and DRSA of the lettuce were 0.1% AMG and B0:R5:W5.

Studies on Cytological Characteristics of Elymus humidus as Genetic Resources Compared to Common Wheat (Triticum aestivum L.)

  • Ji-Yoon Han;Seong-Wook Kang;Sejin Oh;Yumi Lee;Myoung-Jae Shin;Sukyeung Lee;Seong-Woo Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.3
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    • pp.216-223
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    • 2023
  • This study aimed to identify and compare the characteristics of Elymus humidus on common wheat (Triticum aestivum L. cv. Chinse Spring, CS). The seed length, width, height, and weight of E. humidus were smaller than those of the CS. In particular, the germination rate of E. humidus was substantially lower than that of CS. In the anatomical dissection of the leaf, E. humidus showed a considerably different xylem diameter of the main vascular bundle in the main vein; however, there was no difference in the phloem of the main vascular bundle compared with the xylem and phloem of the main vascular bundle in the main vein of CS, although E. humidus showed a leaf structure similar to that of CS. In addition, E. humidus had a thinner epidermis than that of CS. Regarding stomatal traits, E. humidus showed a graminoid stomata type similar to that of CS. On the adaxial and abaxial sides, the density, length, and width of the stomata in E. humidus were smaller than those in CS, whereas the distance between stomata in E. humidus was greater than that in CS. The chromosomes of E. humidus were classified as long and short based on their respective lengths. Long chromosomes were classified based on the ratio of the long arm to the short arm e.g., 1:1 or 2:1. Short chromosomes showed the same trend and some short chromosomes were microsatellites. To evaluate genetic diversity, 38 barley EST markers with polymorphisms between E. humidus and CS were selected from 236 barley EST markers.

Development of the breeding materials with diverse grain size and shape in japonica rice

  • Park, Hyun-Su;Shin, Woon-Chul;Baek, Man-Kee;Nam, Jeong-Kwon;Jeong, Jong-Min;Park, Seul-Gi;Kim, Choon-Song;Cho, Young-Chan;Kim, Bo-Kyeong
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.67-67
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    • 2017
  • We developed the breeding materials with diverse grain size and shape in japonica rice. Grain size and shape are important factors affecting consumer preference and choice. However, most of Korean japonica rice cultivars have small, short, and round grain. To diversify the grain size and shape of japonica rice, we conducted the breeding program using donor parents, Jizi1560 and Jizi1581. Jizi1560 and Jizi1581 are japonica germplasm with extremely large grain. Four crosses between the each donor parents and high yielding japonica rice cultivars, Deuraechan and Boramchan, were constructed and then anther culture method was applied. We obtained 290 doubled-haploid (DH) lines with appropriated morphological traits and selected 91 DH lines with diverse grain size and shape. The grain related-traits of the selected DH lines showed a higher diversity when compared with 319 cultivars developed by NICS (264 japonica, 13 black, and 32 Tongil type cultivars). We designated the selected DH lines, four parents, and Daeripbyeo 1, large grain japonica cultivar, as the breeding materials for further analysis. The breeding materials were classified into five groups, A to E, based on the grain-related traits. Group A (including Jizi1581) and Group B (including Daeripbyeo 1) showed similar grain width, whereas Group A exhibited longer grain length and heavier grain weight. Group C (including Deuraechan and Boramchan) showed shorter and rounder grain shape and smaller grain size than any other groups. Group D including solely Jizi1560 had extremely large grain, such as the longest grain length, width, and thickness and heaviest grain weight. Group E including only two DH lines had long and slender grain shape, so that showed the highest ratio of length to width. The grain size and shape of the breeding materials exhibited beyond the characteristics of previously developed Korean japonica cultivars. The breeding materials will be applied in the breeding programs to diversify the grain size and shape of japonica rice.

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Comparative Morphology of Minute Intestinal Fluke Eggs That Can Occur in Human Stools in the Republic of Korea

  • Lee, Jin-Joo;Jung, Bong-Kwang;Lim, Hye-Mi;Lee, Mi-Youn;Choi, Sung-Yil;Shin, Eun-Hee;Chai, Jong-Yil
    • Parasites, Hosts and Diseases
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    • v.50 no.3
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    • pp.207-213
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    • 2012
  • The egg morphology of minute intestinal flukes (MIF) that can occur as human infections in the Republic of Korea, i.e., Metagonimus yokogawai, M. miyatai, M. takahashii, Heterophyes nocens, Heterophyopsis continua, Stellantchasmus falcatus, Stictodora fuscata, Pygidiopsis summa, and Gymnophalloides seoi, was studied in comparison with Clonorchis sinensis. The adult worms were obtained from residents of endemic areas, and their intrauterine eggs were studied and measured using light microscopy; the length, width, length-width ratio (LWR), and Faust-Meleney index (FMI). Several specimens were processed for scanning electron microscopy (SEM), and before gold-coating, the uterine portion of each fluke was etched with a sharp pin in order to expose the eggs. The MIF eggs were ovoid, pyriform, or elliptical with a size range of $21-35{\times}12-21{\mu}m$. S. fuscata eggs revealed the highest FMI (largest in the area) and lowest LWR, whereas P. summa eggs showed the lowest FMI and medium LWR. SEM revealed that G. seoi and S. fuscata had remarkably clean shell surface lacking the muskmelon-like structure which is prominent in C. sinensis eggs. In Metagonimus spp., H. continua, H. nocens, and S. falcatus eggs, minute surface ridges were recognizable though less prominent compared with C. sinensis. On the surface of P. summa eggs, thread-like curly structures were characteristically seen. The results revealed that important differential keys for MIF eggs include the length, width, area (FMI), shape of the eggs, and the extent of the muskmelon-like structure or ridges on their shell surface and operculum.