• Title/Summary/Keyword: Direct3D

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A Study on the Internet Venture Company (인터넷 벤처기업 창업자의 행위특성에 관한 이론적 연구)

  • 이제홍
    • The Journal of Information Technology
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    • v.4 no.3
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    • pp.101-123
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    • 2001
  • The competitive environments of the 2001s appears to demand not only information technology(IT), but also practical use of internet network in all business areas. Accordingly, Chief Information Officers(CIO) are recognizing that these objectives can only be achieved through conscious mind and business mind in digital management. Thus, the main concern of CIO in an organization is development and management of human resource in digital management innovation. To make a successful organizational innovation CIO needs to have the conscious mind for change of human resource management. To study the determinants of the level of management in Korean venture firms, Top management characteristics, resource dependence and organizational power perspective, rational expectations, There is direct successful factors of Venture firm, it is they got th notion that for venture an appropriate manager which is as important as the technical leadership itself. also they employed the people who are very good at skilled management.

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A CMOS Fully Integrated Wideband Tuning System for Satellite Receivers (위성 수신기용 광대역 튜너 시스템의 CMOS 단일칩화에 관한 연구)

  • Kim, Jae-Wan;Ryu, Sang-Ha;Suh, Bum-Soo;Kim, Sung-Nam;Kim, Chang-Bong;Kim, Soo-Won
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.7
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    • pp.7-15
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    • 2002
  • The digital DBS tuner is designed and implemented in a CMOS process using a direct-conversion architecture that offers a high degree of integration. To generate mathched LO I/Q quadrature signals covering the total input frequency range, a fully integrated ring oscillator is employed. And, to decrease a high level of phase noise of the ring oscillator, a frequency synthesizer is designed using a double loop strucure. This paper proposes and verifies a band selective loop for fast frequency switching time of the double loop frequency synthesizer. The down-conversion mixer with source follower input stages is used for low voltage operation. An experiment implementation of the frequency synthesizer and mixer with integrated a 0.25um CMOS process achieves a switching time of 600us when frequency changes from 950 to 2150MHz. And, the experiment results show a quadrature amplitude mismatch of max. 0.06dB and a quadrature phase mismathc of max. >$3.4^{\circ}$.

Development of a Sizing System of Women's Fitness Wear for the Senior Population in South Korea (한국 노인 여성을 위한 피트니스 압박웨어 치수 개발)

  • Jeon, Eun-Jin;Lee, Won-sup;Park, Jang-Woon;You, Hee-Cheon
    • Fashion & Textile Research Journal
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    • v.20 no.4
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    • pp.464-473
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    • 2018
  • The objective of this study is to develop a sizing system of fitness clothing that can properly accommodate various body sizes of Korean senior women. The sizing system of upper and lower fitness clothing was developed in the present study by selection of key variables, identification of size category candidates, and determination of an optimal sizing system. First, key anthropometric dimensions (stature and bust circumference for upper clothing and stature; waist circumference for lower clothing) were identified by factor analysis on the direct body measurements (n = 272) and 3D whole-body scan data (n = 271) of Korean senior women in Size Korea. Second, sizing system candidates based on the key dimensions of upper and lower clothing were explored using a grid method and an optimization method. Lastly, among the sizing system candidates, optimal sizing systems of upper and lower clothing were selected in terms of accommodation rate. Five size categories (short/small, short/medium, tall/small, tall/medium, and tall/large) were selected as the optimal sizing systems of upper and lower clothing with 89% and 78% of accommodation rate, respectively, for the Korean senior women. The anthropometric characteristics of the representative humans of the optimal size categories would be of use in the design of fitness compressive wear for the better fit and effectiveness of exercise and health of Korean senior women.

Exhaust Emission Characteristics by Alteration of MTBE Contents in D. I. Diesel Engine (직접분사식 디젤기관에서 MTBE 함유율 변화에 의한 배출가스 특성)

  • O, Yeong-Taek;Choe, Seung-Hun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.5
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    • pp.724-732
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    • 2002
  • Although the demands for diesel engine is increased, our world is faced with very serious problems related to the air pollution due to the exhaust emissions of the diesel engine. In this study, the potential possibility of oxygenated fuel such as Methyl tertiary butyl ether (MTBE) was investigated for the sake of exhausted smoke reduction from diesel engine. MTBE has been used as a fuel additive blended into unleaded gasoline to improve octane number, but the study of application for diesel engine was incomplete. Because MTBE includes oxygen content approximately 18%, it is a kind of oxygenated fuel that the smoke emission of MTBE is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at high load and speed in diesel engine. But, the NOx emission of MTBE blended fuel is increased compared with commercial diesel fuel. And. it was tried to analyze not only total hydrocarbon but individual hydrocarbon components from $C_1$to $C_{6}$ in exhaust gas using gas chromatography to seek the reason for remarkable reduction of smoke emission. The results of this study show three conclusions. 1. The smoke omission of the MTBE blended fuel is lower than that of the diesel fuel at all experimental region in direct injection diesel engine. 2. Individual hydrocarbons(C$_1$~ $C_{6}$) as well as total hydrocarbon of oxygenated fuel are reduced remarkably compared with diesel fuel. 3. Smoke emission from diesel engines was strongly depended on oxygen content in fuel regardless of operating condition.

Mutational Analysis of Korean Patients with Phenylketonuria

  • Koo, Soo Kyung;Lee, Kwang-Soo;Jung, Sung-Chul;Lee, Jong-Eun;Lee, Dong Hwan
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.4 no.1
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    • pp.5-12
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    • 2004
  • Purpose Phenylketonuria is an inborn error of metabolism, which is inherited as an autosomal recessive trait. PKU is resulting from deficiency of phenylalanine hydroxylase. PAH gene spans about 90 kb on chromosome 12q and comprises 13 exons. In order to define the genetic basis of PKU and the frequencies and distribution of PAH mutations in the Korean population, we analyzed PAH gene in independent 80 patients with PKU. Methods All 13 exons including exon-intron boundaries and 2 kb of 5' upstream region of the PAH gene were analyzed by PCR-direct sequencing methods. Results PAH gene analysis revealed 39 different mutations including 10 novel mutations. The novel mutations consisted of 9 missense mutations (P69S, G103S, N207D, T278S, P281A, L293M, G332V, S391I and A447P) and a novel splice site variant (IVS10-3C>G). R243Q, IVS4-1G>A, and E6-96A>G were the most relevant mutations and they accounted in the whole for 38% of the mutant alleles identified in this study. We also observed that. $BH_4$ responsibility was. associated with genotype of R241C, R53H and R408Q. Conc1ustion Our present study with 80 participants extends the previous results to more comprehensive understanding of PAH allele distribution and frequency in Koreans. Although Korean mutation profile of PAH is similar to those of the nearest oriental populations (Japanese, Chinese, and Taiwanese), several different characteristic features are revealed. The characterization of the genotype-phenotype relationship was also performed. Our data would be very useful information for diagnosis, genetic counseling and planning of dietary and therapeutic strategies in Korean PAH patients.

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Characteristics of nanolithograpy process on polymer thin-film using near-field scanning optical microscope with a He-Cd laser (He-Cd 레이저와 근접장현미경을 이용한 폴리머박막 나노리소그라피 공정의 특성분석)

  • Kwon S. J.;Kim P. K.;Chun C. M.;Kim D. Y.;Chang W. S.;Jeong S. H.
    • Laser Solutions
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    • v.7 no.3
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    • pp.37-46
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    • 2004
  • The shape and size variations of the nanopatterns produced on a polymer film using a near-field scanning optical microscope(NSOM) are investigated with respect to the process variables. A cantilever type nanoprobe having a 100nm aperture at the apex of the pyramidal tip is used with the NSOM and a He-Cd laser at a wavelength of 442nm as the illumination source. Patterning characteristics are examined for different laser beam power at the entrance side of the aperture($P_{in}$), scan speed of the piezo stage(V), repeated scanning over the same pattern, and operation modes of the NSOM(DC and AC modes). The pattern size remained almost the same for equal linear energy density. Pattern size decreased for lower laser beam power and greater scan speed, leading to a minimum pattern width of around 50nm at $P_{in}=1.2{\mu}W\;and\;V=12{\mu}m/s$. Direct writing of an arbitrary pattern with a line width of about 150nm was demonstrated to verify the feasibility of this technique for nanomask fabrication. Application on high-density data storage is discussed.

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Effect of Supplemental Fish Meal on Milk Yield and Milk Composition of Holstein Cows during Early Lactation

  • Adachi, N.;Suzuki, K.;Kasai, K.;Hiroki, M.;Kume, S.;Nonaka, I.;Abe, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.3
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    • pp.329-333
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    • 2000
  • Data of 15 multiparous Holstein cows kept at Ibaraki Prefectural Animal Experiment Station were collected from 10 weeks prepartum to 20 weeks postpartum. Cows were assigned randomly to a soybean meal (S8M) diet or a fish meal (FM) diet from 4 weeks before expected calving date to 20 weeks postpartum. Each diet was formulated to contain similar amounts of CP, ADF, and NDF. In the FM diet, 2.5 and 5% of fish meal were supplemented as total mixed rations in prepartum and postpartum periods, respectively. Compared to the SBM diet, undegraded intake protein (UIP) and Met were higher in the FM diet, but Lys was low. Body weight and dry matter intake were not affected by supplemental FM, and dry matter intake increased by 6 weeks postpartum and maintained constant after 7 weeks postpartum. Cows in the FM diet remained high milk production during the experimental period, but milk yield in the SBM diet decreased gradually after 6 weeks postpartum. Supplemental FM increased milk yield and protein yield from 10 to 20 weeks postpartum when FM intake was 1.19 kg/d, although milk protein was not improved. There were no significance differences in fat content and fat yield between FM and SBM diets. Supplemental FM had no effect on plasma glucose and urea-N at parturition and 7 weeks postpartum. Thus, the increased milk and protein yield may be due to the combination of carryover effect of supplemental UIP or Met in FM from 4 weeks prepartum to 10 weeks postpartum and direct effect of supplemental FM.

Accuracy Simulation of Precision Rotary Motion Systems (회전운동 시스템의 정밀도 시뮬레이션 기술)

  • Hwang, Joo-Ho;Shim, Jong-Youp;Hong, Seong-Wook;Lee, Deug-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.3
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    • pp.285-291
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    • 2011
  • The error motion of a machine tool spindle directly affects the surface errors of machined parts. The error motions of the spindle are not desired errors in the three linear direction motions and two rotating motions. Those are usually due to the imperfect of bearings, stiffness of spindle, assembly errors, external force or unbalance of rotors. The error motions of the spindle have been needed to be decreased to desired goal of spindle's performance. The level of error motion is needed to be estimated during the design and assembly process of the spindle. In this paper, the estimation method for the five degree of freedom (5 D.O.F) error motions of the spindle is suggested. To estimate the error motions of the spindle, waviness of shaft and bearings, external force model was used as input data. And, the estimation models are considering geometric relationship and force equilibrium of the five degree of the freedom. To calculate error motions of the spindle, not only imperfection of the shaft, bearings, such as rolling element bearing, hydrostatic bearing, and aerostatic bearing, but also driving elements such as worm, pulley, and direct driving motor systems, were considered.

Effects of PEO Conditions on Surface Properties of AZ91 Mg Alloy (PEO 처리조건에 따른 마그네슘 합금 AZ91의 표면특성변화에 관한 연구)

  • Park, Kyeong-Jin;Jung, Myung-Won;Lee, Jae-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.3
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    • pp.71-77
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    • 2010
  • Mg alloys have been used in automobile industry, aerospace, mobile phone and computer parts owing to low density. However, they have a restricted application because of low mechanical and poor corrosion properties. Thus, improved surface treatments are required to produce protective films. Environmental friendly Plasma Electrolytic Oxidation(PEO) was used to produce protective films on magnesium alloys. PEO process is combined electrochemical oxidation with plasma treatment in the aqueous solution. In this study, the effects of applied voltage and applied current on the surface morphologies were investigated. Also, the effects of Direct Current(DC) and Pulse Current(PC) were compared. PC and constant current control gave the dense coating on the Mg alloy. The potentiodynamic polarization tests were carried out for the analysis of corrosion properties of specimens. The surface hardness was 5 times higher than that of untreated AZ91D.

Interference Analysis of TV Signal Affected by Flights of An Airplane around KimPo International Airport Circumference (항공기 운항으로 인한 김포국제공항 주변지역의 TV 수신 장애 분석)

  • Lee, Chan-Joo;Kim, Bong-Cheol;Cho, Sung-Joon
    • Journal of Advanced Navigation Technology
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    • v.3 no.1
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    • pp.20-31
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    • 1999
  • In this paper, we have chosen KimPo International Airport as an area for estimating the flutter interference, in order to analyze the flutter interference. The field test at 25 points around KimPo International Airport and the simulation have been performed for estimating the flutter interference. We consider the received power of a direct wave, the height of an antenna, the ERP of a transmitting point, transmit frequency, and the reflection coefficients of an airplane, the transmit/receive point coordinates as estimation functions for the flutter. From the results, we have found that the flutter interference from flights is very serious around the route of flight circumference, and often occurs when the height of an airplane is low, range from 40 to 240 m. Besides, the degree of the flutter interference can be changed according to the distance between an airplane and a transmitting point, elevation angle, and the reflection coefficients of an airplane.

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