• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.57.1-57.1
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• 2017

As an upgrade we report the current ASTE ultra-wideband corrugated horn design. The length of the feedhorn gets shortened from 12.5 mm to 11 mm, and it shows better side lobe level at the far-field patterns compared with the previous design. We looked into possible quasi-optical solution to match the feedhorn beam to the optics of the current ASTE telescope, starting from frequency-independent solution using two ellipsoidal mirrors to which wideband performance of the feedhorn naturally fits. We used a commercial physical optics package (GRASP) with an user-defined optimizer to give physical constraints to evaluated optical designs for highest efficiency.

• Korean Journal of English Language and Linguistics
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• v.2 no.4
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• pp.555-574
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• 2002

This study concerns the constraints of English Poetic Meter. In English poems, the metrical pattern doesn't always match the linguistic stress on the lines. These mismatches are found differently among the poets. For the lexical stress mismatched with the weak metrical position, W⇒ Strength is established by the concept of the strong syllable. The peaks of monosyllabic words mismatched with the weak metrical position are divided according to which side of the boundary of a phonological domain they are adjacent to. Adjacency Constraint I is suggested for the mismatched peak which is adjacent to the left boundary of a phonological domain; /sup */Peak] and Adjacency ConstraintⅡ for the mismatched peak which is adjacent to the right boundary of a phonological domain. These constraints are various according to the poets (Pope, Milton and Shakespeare) : /sup */[Peak [-stress], /sup */W⇒ Strength and /sup */Peak] in Pope; /sup */[+stress][Peak[-stress] and /sup */Peak] in Milton; /sup */[ +stress][Peak[-stress], /sup */W⇒Strength and Adjacency ConstraintⅡ in Shakespeare.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.3
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• pp.115-122
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• 2008

Wu and Tsai's pixel-value differencing method and Chang and Tseng's side-match method are based on the theory that the number of bits which can be embedded is determined by the degree of the pixel's smoothness, or its proximity to the edge of the image. If pixels are located in the edge area, they may tolerate larger changes than those in smooth areas. However, both methods are subject to the fall off the boundary problem(FOBP). This study proposes a new scheme that can solve the FOBP. The experimental results demonstrate that the proposed method resolves the problem, and achieves a higher image quality index value than other methods.

• The KSFM Journal of Fluid Machinery
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• v.14 no.6
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• pp.54-60
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• 2011

This paper presents the steady-state performance analysis of the first stage of a multistage centrifugal pump, composed of a shrouded-impeller, a vaned-diffuser and a return-channel, using the commercially available computational fluid dynamics (CFD) code, ANSYS CFX. The detailed flow fields in the vaned-diffuser with outlet in its side wall and the return-channel are investigated by the CFD code adopted in the present study. The effect of the vaned-diffuser with a downstream crossover bend and the corresponding return-channel on the overall hydrodynamic performance of the first stage pump has also been demonstrated over the normal operating conditions. The predicted hydrodynamics for the diffusing components herein could provide useful information to match the inlet blade angle of the next stage impeller for improving the multistage pump performances.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.1
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• pp.7-12
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• 2004

Trichophyton(T.) tonsurans has been identified for the first time in Korea in 1995 and has been increasing in number of reported in wrestlers, in judo players, and in korean - style wrestlers. Author tried mycological studies with T. tonsurans is isolated in Daegu Korea. The results are as follows: All 16 strains of T. tonsurans tested for nutritional requirement, showed strongly stimulated growth by thiamine, mild to moderate growth on casamino acid agar, poor growth on ammonium nitrates base agar. All 16 strains of T. tonsurans tested showed positive results for hair perforation and urease test. Gross findings of T. tonsurans showed that fine granular surface with light yellow hue or white color and mahogany brown color on the reverse side. Microscopic findings showed that septated hyphae, chlamydoconidia and microcondia. Microconidia were characteristic in their arrangerment and shape : round or oval shaped microconidia laterally to hyphae, some were match - head like terminal swelling.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2372-2382
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• 1998

In this paper, we propose a new edge based finite state vector quantization method having better performance than conventional side-match finite state vector quantization. In our proposed scheme, each dCT transformed block is classified to 17 classes according to edge types. Each class has a different codebook based on its characteristis. Encoder classified each block to motion block or stationary block and constructed a merging map by using edge and motion information, and sent to decoder. We controled amoutn of bing bits transmitted with selecting modes accoridng to bandwidth of transmitting channel. Compared with conventional algorithms, H.263 and H.261 at low bit rate, our proposed algorithm shows better picture quality and good performance.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2167-2169
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• 1999

A pulse transformer producing pulses with the peak power of 200-MW (400 kV 500 A at load side with $4.4{\mu}s$ flat-top) is required to drive the 80-MW pulsed klystron in the PLS linac. We have designed and manufactured the high power pulse transformer with 1 : 17 turn ratio. Its primary functions are to match the impedance of klystron tube to the modulators, and to provide step-up of the voltage. To obtain a fast rise time of the pulse voltage. Low leakage inductance and low distributed capacitance design is very important. In this paper, we discuss the equivalent circuit analysis of the pulse transformer, and present the full power performance test results of pulse transformer.

• Journal of the Korea Safety Management & Science
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• v.11 no.3
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• pp.87-94
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• 2009

Today's driver information system often features a rotary control type as a main controller for menu navigation. Population stereotype should be clearly understood in designing those systems to minimize the misunderstanding by the operator. This paper investigates stereotypes for rotary controlled menu interfaces and influences of contributing principles. A human factors experiment was conducted using various configurations of control-display layouts, cursor shapes/positions, and movement directions. The results showed that the control should be on the left of the display, with a rightward icon on the right side of the cursor, in order to match the stereotype. Regression analysis indicated that Warrick's principle was the most influential principle, followed by Icon shape, Icon position, Clockwise away, and Clockwise up principles. This study provides valuable information to designers of menu-based systems such as driver information systems and main control rooms that uses rotary controls.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.4 no.1
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• pp.1-5
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• 1995

A mucogingival grafting procedure has been developed to cover denuded root surfaces. This procedures need to connective tissue, so many clinician open the trap door to palatal side of the patient. In this study, where palatal pocketing was present, pocket elimination was performed, and the tissue normally discarded after thinning of the palatal flap was used as a grafting material. The esthetics in recipient site, both color match and tissue contour were acceptable to the patient in this case.

• The Transactions of the Korea Information Processing Society
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• v.7 no.3
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• pp.1013-1020
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• 2000

In this paper, we propose an algorithm which segments hierarchically blocks of image using discrete cosine transform(DCT) and execute finite-state vector quantization (FSVQ) for each block. Using DCT coefficient feature, image is segmented hierarchically to large smooth block and small edge block, then the block hierarchy informations are transmitted. The codebooks are respectively constructed for each hierarchical blocks, the encoder transmits codeword index using FSVQ for reducing encoded bit with hierarchical segmentation. Compared with side match VQ(SMVQ) and hierarchical FSVQ(HFSVQ) algorithm, about Zelda and Boat image, the new algorithm shows better picture quality with 1.97dB and 2.85 dB difference as to SMVQ, 1.78dB and 1.85dB diffences as to HFSVQ respectively.