• Journal of Biosystems Engineering
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• v.38 no.2
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• pp.73-80
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• 2013

Purpose: This study was conducted to compare tillage and loads characteristics of three types of rotavators in farmland working condition of Korea. Methods: Tillage operations using three types of rotavators, i.e. rotary-type, crank-type and plow-type, were carried out in a dry field of Korea. The same prime mover tractor was used for driving three types of rotavators, and under several operational conditions, tillage characteristics such as actual working speed, rotavating depth, rotavating width, actual field capacity, flow of tilled soil, soil inversion ratio, and pulverizing ratio were measured. In addition, loads characteristics like torque and required power of Power Take-Off (PTO) shaft were calculated. Results: The average rotavating depth was smaller than the nominal value for all rotavators, and the difference was the greatest in the plow-type rotavator. Nevertheless, the plow-type rotavator showed the largest rotavating depth. The rotavating width was the same as the nominal value of all rotavators. The flow of tilled soil at the same operational conditions was the greatest in the plow-type rotavator and was the smallest in the rotary-type rotavator. In the most commonly used gear conditions of L2 and L3, the average soil pulverizing ratio was the greatest in the rotary-type rotavator, and followed by crank-type and plow-type rotavators in order. In the gear L2 and L3, the plow-type rotavator also had the lowest average soil inversion ratio while the rotary-type and crank-type rotavators had the same soil inversion ratio each other. The average torque and power of PTO shaft in the gear L2 and L3 were the highest in the plow-type rotavator. The load spectra of PTO shaft applying rain flow counting method and Smith-Waston-Topper equation to the measured torque showed that the modified torque amplitude was the greatest in the crank-type rotavator. This may come from the large torque fluctuation of crank-type rotavator during tillage operations. Conclusions: The three types of rotavators had different tillage and loads characteristics. The plow-type rotavator had the deepest rotavating depth, the smallest soil inversion ratio, the largest soil pulverizing ratio and required PTO power. Also, the crank-type rotavator showed a large torque fluctuation because of their unique operational mechanism. This study will help the farmers choose a suitable type of rotavator for effective tillage operations.

• Parasites, Hosts and Diseases
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• v.45 no.2 s.142
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• pp.103-109
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• 2007

Leishmania tropica and L. major are etiologic agents of human cutaneous leishmaniasis. Delayed type hypersensitivity (DTH) is an immunologic response that has been frequently used as a correlate for protection against or sensitization to leishmania antigen. In BALB/c mice, L. tropica infection results in non-ulcerating disease, whereas L. major infection results in destructive lesions. In order to clarify the immunologic mechanisms of these 2 different outcomes, we compared the ability of these 2 leishmania species in induction of DTH response in this murine model. BALB/c mice were infected with L. major or L. tropica, and disease evolution and DTH responses were determined. The results show that the primary L. major infection can exacerbate the secondary L. major infection and is associated with DTH response. Higher doses of the primary L. major infection result in more disease exacerbation of the secondary L. major infection as well as higher DTH response. L. tropica infection induces lower DTH responses than L. major. We have previously reported that the primary L. tropica infection induces partial protection against the secondary L. major infection in BALB/c mice. Induction of lower DTH response by L. tropica suggests that the protection induced against L. major by prior L. tropica infection may be due to suppression of DTH response.

• Bulletin of the Korean Mathematical Society
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• v.50 no.4
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• pp.1345-1356
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• 2013

In this paper, we study rotational and helicoidal surfaces in Euclidean 3-space in terms of their Gauss map. We obtain a complete classification of these type of surfaces whose Gauss maps G satisfy $L_1G=f(G+C)$ for some constant vector $C{\in}\mathbb{E}^3$ and smooth function $f$, where $L_1$ denotes the Cheng-Yau operator.

• Journal of the Korean Mathematical Society
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• v.46 no.2
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• pp.347-361
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• 2009

In this paper, by estimating small ball probabilities of $l^{\infty}$-valued Gaussian processes, we investigate Chung-type law of the iterated logarithm of $l^{\infty}$-valued Gaussian processes. As an application, the Chung-type law of the iterated logarithm of $l^{\infty}$-valued fractional Brownian motion is established.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.2
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• pp.115-118
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• 2001

본 논문에서는 L-R 퍼지수의 집합-이론적 연산의 개념을 정의하고, 이들 개념의 성질들을 조사한다. 이들 연산들의 결과들을 이용하여 제2형 퍼지집합의 기수개념에 관하여 연구한다.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.294-296
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• 1997

LOA(Linear Oscillating Actuator) is composed of a voice coil type mover and permanent magnets. we have applied LOA to the active vibration control system to supress structual vibration. In this paper, the static test of the voice coil type LOA is treated. The thrust developed by LOA is calculated by measuring stroke.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.235-238
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• 1990

Complexes of the type[Co(T)(L-pro)], where T is the quadridentate $N_2O_2$-type ligand, N,N'-dimethylethylenediamine-N,N'-diacetate or N,N'-dimethylethylenediamine-N,N'-di-$\alpha$-butyrate, have been prepared. The complexes were separated into the two stereoisomers, $\Delta$-s-cis-[Co(T)(L-pro)] and $\Lambda$-s-cis-[Co(T)(L-pro)]. They were characterized by their proton magnetic resonance, absorption and circular dichroism spectra, elemental analyses.

• Honam Mathematical Journal
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• v.29 no.2
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• pp.269-277
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• 2007

Let L := L(G) denote the classical modular Lie algebra of $E_6$-type over an algebraically closed field F of characteristic p > 5 associated with some simple and simply connected algebraic group G. After the prototypes of those for $E_8$-type in [4], we shall search for irreducible (=simple) L-modules in this paper.

• Korean Journal of Mathematics
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• v.30 no.1
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• pp.121-130
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• 2022

In this paper, we prove that every semi-conformal harmonic map between Riemannian manifolds is L-harmonic map. We also prove a Liouville type theorem for L-harmonic maps.

• Korean Institute of Interior Design Journal
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• v.21 no.2
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• pp.163-173
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• 2012

In this study, the spatial analysis of the multi-housing unit plans was investigated since 1990 for the winners at the architectural competition which was held nationwide in Germany. The investigation was carried out from January in 1990 to December in 2010. 201Unit plans were analyzed. Space syntax model is used as analyzing tool of the Unit plans. The results of the study indicate followings: 1) The interior spaces in 3LDK types and 4LDK types, ordered by high value of integration are; (1) corridor, (2) entrance hall, (3) living room, (4) dining room. 2) The value of integration for the kitchen is higher in L/DK type than in LD/K type, and that for the living room is higher in LD/K type than in L/DK type. The mean value of integration for L/DK type is higher than that for LD/K type. This means that traffic line efficiency of L/DK type is higher than that of LD/K type. 3) The value of integration for corridor and entrance hall is gradually lower in recent years. That is, the type of Unit plans are changing from corridor types to hall types.