• Fire Science and Engineering
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• v.24 no.2
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• pp.38-43
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• 2010

The purpose of this study is to secure the basis for judgment on the cause of an accident by analyzing the melting characteristics of a blade type fuse used for vehicles due to overload. In order to increase the reliability of the test, it was conducted by connecting the electrical system with conditions similar to those of an actual vehicle to apply the load. Carbonization pattern experiment of fuse by outside flame applied Korean Standard (KS). The fuse melted by the overcurrent showed a smooth cross-section while the test terminals, clear plastic body, etc., burnt out by the external flame was badly deformed. When 185% of the rated current (27.8A) was applied to a cable of 15A rated current onto which an over-capacity fuse (20A) was installed, the fuse melting time was 217 seconds. In addition, when a load current of 28.8[A] (139%) was applied, the fuse's test terminal and terminal blade were not burnt out although foam was observed on some parts of the plastic body. When a load capacity of 28.2[A] (141%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melting time was approximately 10 seconds. When a load current of 35.8[A] (119%) was applied, the fuse's test terminal and terminal blade were not burnt out, although some parts of the plastic body was swelled. However, it was observed that the switch terminal melted if approximately six minutes lapsed under such conditions. When a load capacity of 39.4[A] (131%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melted in approximately 69 seconds, and the test terminal and terminal blade were not burnt.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.2011-2015
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• 2009

In an insulating dielectric liquid such as transformer oil, space charge injection and propagation were analyzed under the Fowler-Nordheim and Richardson-Dushman's thermal emission charge injection conditions for blade-plane electrodes stressed by a step voltage. The governing equations were composed of all five equations such as the Poisson's equation for electric fields, three continuity equations for electrons, negative, and positive ions, and energy balanced equation for temperature distributions. The governing equations for each carrier, the continuity equations, belong to the hyperbolic-type PDE of which the solution has a step change at the space charge front resulting in numerical instabilities. To decrease these instabilities, the governing equations were solved simultaneously by the Finite Element Method (FEM) employing the artificial diffusion scheme as a stabilization technique. Additionally, the terminal current was calculated by using the generalized energy method which is based on the Poynting's theorem, and represents more reliable and stable approach for evaluating discharge current. To verify the proposed method, the discharge phenomena were successfully applied to the blade~plane electrodes, where the radius of blade cap was $50{\mu}m$.

• Animal cells and systems
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• v.1 no.2
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• pp.313-316
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• 1997

Thomas'fruit-eating bat, Artibeus watssoni, is known to alter leaves of a wide variety of tropical plants to construct tent roosts. On Barro Colorado Island and Gigante Peninsula in the canal zone, Panama, A. watsoni is found to use the black palm, Astrocaryum standleyanum, as its tent plant. Bats cut the first five to ten pinnae from the proximal side of the terminal blade and chew additional four to nine pinnae without severing their central veins. The distance from the frond rachis to the cut decreases distally leaving an inverted V-shaped cut path. The distal portions of the bifurcated blade are then collapsed and folded to form the'bifid'tent with an inverted boat-shaped cavity underneath. All tents were in fronds of trunkless juvenile plants.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10a
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• pp.759-764
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• 1987

The design and application of optimal control technique to the rotary shearing system is mentioned in this paper. To maximize the accuracy in both shearing length and blade speed at shearing, time-varying gain patterns for closed loop control are designed on the basis of fixed terminal time constrained optimal regulator. The performance accuracy in real application has greatly improved than the conventional way of shearing control.

• Korean Journal of Plant Taxonomy
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• v.44 no.3
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• pp.171-174
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• 2014

A new species, Pseudostellaria baekdusanensis M. Kim (Caryophyllaceae), has been named and described from Mt. Baekdu of the Korean peninsula. Pseudostellaria baekdusanensis shares several characteristics (same size leaves, axillary or terminal flowers, emaginate petals, etc.) with its related species P. japonica (Korshinsky) Pax. It is, however, distinct from P. japonica which have large plant (25-35 cm), leaf blade margins and midveins with long hairs, shallow emaginate petal apex, (2) 3 styles, and cleistogamic flowers by having small plants (9-13 cm), leaf blade basal margins with long hairs, deep emaginate petal apex, 2 styles, and non-cleistogamic flowers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.273-278
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• 1998

Carbohydrate metabolism and partitioning are dependent on relationships between sources and sinks which can be affected by rates of photosynthesis and respiration. Fructan, the major form of stored carbohydrate in tall fescue (festuca arundineacea Schreb.), changes in concentration during growth and in response to the environment. Objectives of this study were i) to examine the content and the composition of carbohydrates in five tissues (mature leaf blade, immature leaf blade, leaf elongation zone, terminal meristem, and root tips) of two tall fescue genotypes, one with high yield per tiller (HYT) and one with low yield per tiller (LYT), and ii) to compare the reserved and utilized carbohydrates among above five different tissues, particularly between the leaf elongation zone and root tips. The established vegetative tillers of the HYT and LYT genotypes were grown in a controlled-environment growth chamber. Water-soluble carbohydrate (WSC) in the leaf elongation zone was about 22% of dry weight in the HYT and about 19% in the LYT genotype. The root tip also had high WSC, about 12% of dry weight in the HYT and 6% in the LYT genotype. Hexoses and sucrose were the major components of total WSC in all tissues except the leaf elongation zone. The growing tissues (sinks), i.e., the leaf elongation zone and root tip, had a high proportion of low degree of polymerization fructan, i.e., 3 to 8 hexose units.

• ALGAE
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• v.20 no.4
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• pp.279-293
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• 2005

Two new species of Martensia (Delesseriaceae, Rhodophyta) are described from Jeju Island, Korea. Martensia palmata sp. nov. is characterized by the following traits: more or less linearly elongated lobes arising from the distal margin of the flabellate membranous section; intact latticework with coarse and loose mesh; numerous spine-like projections on the leading margin of the latticework; tetrasporangia produced in sori along the entire blade; spermatangia borne in sori on the membranous section and the longitudinal lamellae of the latticework; and cystocarps borne on the margins of the membranous section. Martensia projecta sp. nov. has the following characteristics: subdichotomously furcated blades, with terminal segments slightly attenuated toward the apex; blades with uneven surfaces; basal parts with a multi-layered parenchymatous construction; small and poorlydefined latticework; tetrasporangia and spermatangia produced in sori on the membranous section; and cystocarps borne on the marginal surfaces of the blades. The existence of M. projecta sp. nov. supports the proposal that the genus Opephyllum Schmitz in Schmitz et Hauptfleisch should be assigned to the genus Martensia.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.451-456
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• 2020

In this paper, we studied the method of designing a embedded antenna for mounting on the JTDLS complete aircraft. The proposed antenna satisfies the MIDS-LVT operation frequency band and is designed as a broadband in consideration of expandability. As a result of the design, it was confirmed that the proposed antenna has similar electrical performance to the existing blade antenna and has broadband characteristics. As a result of EM analysis, the antenna was mounted on the top and bottom parts of the aircraft to check the mount of the aircraft, and it was confirmed that both the top and bottom parts had good radiation characteristics. The technology acquired through this study is judged to be applicable to the JTDLS completed aircraft.

• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.55-61
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• 2009

This paper describes a point of production(POP) system which collects and manages real-time shop floor machining information in a wafer dicing process. The system are composed of POP terminal, line controller and network. In the configuration of the system, LAN and RS485 network are used for connection with the upper management system and down stratum respectively. As a bridge between POP terminal and server, a line controller is used. The real-time information which is the base of production management are collected from information resources such as machine, product and worker. The collected information are used for the calculation of optimal cutting condition. The collection of the information includes cutting speed, spout of pure water, accumulated count of cut in process for blade and wafer defect. In order to manage machining information in wafer dicing process, production planning information is delivered to the shop floor, and production result information is collected from the shop floor, delivered to the server and used for managing production plan. From the result of the system application, production progress status, work and non-working hour analysis for each machine, and wafer defect analysis are available, and they are used for quality and productivity improvements in wafer dicing process. A case study is implemented to evaluate the performance of the system.

• Journal of fish pathology
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• v.11 no.2
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• pp.119-127
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• 1998

Two species of the parasitc copepods, Clavellopsis hugu (Lemaeopodidae; Siphonostomatoida) and Taeniacanthus yamagutii (Taeniacanthidae; Poecilostomatoida) from cultured Korean fish, Takifugu obscurus, is described and reported for the first time in Korea. The parasite was recovered from the buccal cavity, nose and skin. Clavellopsis hugu is easily identified by the body shape, 2nd antenna, mandible and 2nd maxillae. In female, cephalothorax flexed dorsally, second antenna biramose, mandible with serrate blade, second maxillae completely fused at base of cephalothorax. In male, cephalothorax and trunk fused into an ovoid, two pairs of maxillipeds chelate. The most distinctive features of Taeniacanthus yamagutii are terminal process of second maxilla stout, maxilliped claw with conspicuous digitiform process at base and a setiform element at the tip of each exopod spine of legs 2-4. Both parasitic copepod species are new to the Korean fauna. The korean fish, Takifugu obscurus should be considered as an additional host of this species because these parasite were recovered from the western coast of Korea (Boryung Hatchery).