• Title/Summary/Keyword: Polytechnic College

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Design and Fabrication of DWDM Multiplexer Using Optical Fiber Biconical Tapered Couplers (광섬유 용융인장 방법에 의한 DWDM용 광다중화기의 제작)

  • Chang, Jin-Hyeon;Kim, Myoung-Saeng;Kang, Duk-Keun
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.3 no.2
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    • pp.51-60
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    • 2004
  • In this paper, 8-channel multiplexer with 100GHz channel spacing is fabricated. The 8-channel multiplexer is fabricated by connecting three cascaded Mach Zehnder Interferometer (MZI) of optical fiber type, and each interferometer has the wavelength interval of 100GHz, 200GHz and 400GHz, respectively. furthermore, to acquire uniform insertion loss, it is fabricated by using Wavelength Flatten Coupler (WFC) in which the variation of insertion loss is low. Especially, the variation of wavelength interval in the output is explicitly simulated as a function of optical path difference, and the wavelength coupling process along with cascaded connection is discussed. $CO_2$ laser to adjust precisely the wavelength. In summary, The prototype composed by eight cascaded MZI has an insertion loss of 2.1dB, the bandwidth of 0.8nm at 5.5dB point, and channel crosstalk of 25dB Furthermore, the loss dependent on polarization is measured as 0.06dB.

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Combined effect of initial biomass density and nitrogen concentration on growth and astaxanthin production of Haematococcus pluvialis (Chlorophyta) in outdoor cultivation

  • Wang, Junfeng;Sommerfeld, Milton R.;Lu, Congming;Hu, Qiang
    • ALGAE
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    • v.28 no.2
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    • pp.193-202
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    • 2013
  • Nitrogen availability and cell density each affects growth and cellular astaxanthin content of Haematococcus pluvialis, but possible combined effects of these two factors on the content and productivity of astaxanthin, especially under outdoor culture conditions, is less understood. In this study, the effects of the initial biomass densities IBDs of 0.1, 0.5, 0.8, 1.5, 2.7, 3.5, and 5.0 g $L^{-1}$ DW and initial nitrogen concentrations of 0, 4.4, 8.8, and 17.6 mM nitrate on growth and cellular astaxanthin content of H. pluvialis Flotow K-0084 were investigated in outdoor glass column photobioreactors in a batch culture mode. A low IBD of 0.1 g $L^{-1}$ DW led to photo-bleaching of the culture within 1-2 days. When the IBD was 0.5 g $L^{-1}$ and above, the rate at which the increase in biomass density and the astaxanthin content on a per cell basis was higher at lower IBD. When the IBD was optimal (i.e., 0.8 g $L^{-1}$), the maximum astaxanthin content of 3.8% of DW was obtained in the absence of nitrogen, whereas the maximum astaxanthin productivity of 16.0 mg $L^{-1}\;d^{-1}$ was obtained in the same IBD culture containing 4.4 mM nitrogen. The strategies for achieving maximum Haematococcus biomass productivity and for maximum cellular astaxanthin content are discussed.

Method for Increasing the Yield of the Production of Carrot Single Cell by Using Gums (검류를 이용한 단세포 당근 제조 수율 향상 방법)

  • Koh, Jong-Ho;Lee, Jungno;Kim, Hyuk-Hwa
    • Food Engineering Progress
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    • v.13 no.4
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    • pp.348-351
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    • 2009
  • In this study, the effects of gums (guar gum, xanthan gum, locust beam gum) on the activity of polygalacturonase(PGase) were examined. PGase activity was assayed by measuring the release of reducing groups from polygalacturonic acid. Guar gum, xanthan gum and locust bean gum were capable of increasing the catalytic activity of the PGase by 105%, 87% and 90%, respectively. Carrot was macerated by Macerozyme R-200 with gums and the yield of the maceration reaction for the production of carrot single cells was increased up to 13% in the presence of guar gum. This suggested that gums stated above can be used as good enhancers not only for the catalytic activity of the PGase but also for the production of carrot single cell.

Investigation of the Current Status of Domestic Contact-Lens (국내 콘택트렌즈 시장 현황 조사)

  • Lee, Won Jin;Sung, Duk-Yong;Youk, Do Jin;Kang, Sung Soo
    • Journal of Korean Ophthalmic Optics Society
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    • v.7 no.2
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    • pp.79-87
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    • 2002
  • To analyze the current status of contact-lens in domestic, we analyzed the data of "The Spectacles-wearing Rate Analysis in 1999 (Korea Gallup Research)", "Industry current status(Korea Medical Instruments Industrial cooperative}", "Export & Import current status (Korea Customs Service)", and finally reached the following conclusions. 1. The number of contact-lens wearers in domestic could be assumed 2.13 millions. 2. The size of contact lens market in domestic(on year 2000 basis) was about 25.3 billion Korean wons(\) in total ; 10.8 billion Korean wons on the basis of production unit price (Domestic Gross Production Amount-Export Amount : used the subtraction in math), 14.5 billion Korean wons on Import unit price basis. 3. According to the year 2001 data, the import amount of contact lens is 1.7 times greater than export amount of that. 4. The contact lens export status in year 2001 was Japan, Singapore, Taiwan, U.S.A, China, Hong Kong, Malaysia, Thai, - in order. Especially, the contact lens export of China has increased gradually every year since 1998, the first export year of contact lens. 5. The import status of contact lens was U.S.A, Japan, England, Indonesia, Argentina, Taiwan, Hong Kong, - in order. In addition, the consumption trend of contact lens consumers in domestic reflects that famous foreign contact lens brands were much preferred than lower price contact lens imported from several developing countries.

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SNPchaser : A Web-based Program for Detecting SNPs Substitution and Heterozygosity Existence (SNPchaser : DNA서열의 SNPs 치환 및 Heterozygosity 확인 프로그램)

  • Jang, Jin-Woo;Lee, Hyun-Chul;Lee, Myung-Hoon;Choi, Yeon-Shik;Choo, Dong-Won;Park, Kie-Jung;Lee, Dae-Sang
    • KSBB Journal
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    • v.24 no.4
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    • pp.410-414
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    • 2009
  • Single-nucleotide polymorphisms (SNPs) are the DNA sequences difference among the same species in the level of nucleic acids and are widely applied in clinical fields such as personalized medicine. The routine and labor-intensive methods to determine SNPs are performing the sequence homology search by using BLAST and navigating the trace of chromatogram files generated by high-throughput DNA sequencing machine by using Chromas program. In this paper, we developed SNPchaser, a web-based program for detecting SNPs substitution and heterozygosity existence, to improve the labor-intensive method in determining SNPs. SNPchaser performed sequence alignment and visualized the suspected region of SNPs by using user's reference sequence, AB1 files, and positional information of SNPs. It simultaneously provided the results of sequences alignment and chromatogram of relevant area of SNPs to user. In addition, SNPchaser can easily determine existence of heterozygosity in SNPs area. SNPchaser is freely accessible via the web site http://www.bioinformatics.ac.kr/SNPchaser and the source codes are available for academic research purpose.

Image Evaluation according to Formative Properties of Hat and the Garment in the Fashion Collection (패션컬렉션에 나타난 모자와 의복의 조형성에 따른 이미지 평가)

  • Jeong, Hae-Son;Kang, Kyung-Ja;Jeong, Su-Jin
    • Korean Journal of Human Ecology
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    • v.15 no.6
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    • pp.1049-1062
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    • 2006
  • The purpose of this study is to find out the image according to formative properties of hat and garment in the fashion collection. For the study, the 96 stimuli found frequently in fashion collection from the S/S season of 1998 to the F/W season of 2004 were selected. Sets of stimulus and response scales (7 point semantic) were used as experimental materials. The stimuli were 96 pictures with the types of hat(4), the lengths of hair(3), the types of garment(3), the relations between the color of garment and hat(4), and the materials(4) and patterns of garment(2). The subjects were 415 women college students majoring fashion design related fields and living in Seoul and Gyeongsangnam-do. As statistical methods for data analysis, Factor Analysis, ANOVA test, and LSD test were used. The items of the adjectives were classified into 5 image dimensions; attractiveness, gracefulness, concentration, cuteness, and hardness and softness. Among these factors, each dimensional image was affected by formative properties of hat and garment. The image of a hat-wearer was perceived differently according to the hair style and the formative properties of hat and garment even if the type of hat was same.

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A study on the Algorithm for Mesh Network Topology Optimization and Routing (망토폴로지 최적화와 라우팅을 위한 알고리즘에 대한 연구)

  • Kim, Dong-Choon;Na, Seung-Kwon;Pyeon, Yong-Kug
    • Journal of Advanced Navigation Technology
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    • v.19 no.1
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    • pp.53-59
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    • 2015
  • We consider the problems that consist of designing time, establishment cost, delay time and reliability in designing a mesh network when given link costs and traffic requirements between nodes. Designing time, establishment cost and delay time are less, reliability is higher in designing a mesh network. One of the problems designing time is solved by mesh network topology optimization and routing (MENTOR) algorithm that Aaron Kershenbaum propose, but the others remain. In this paper we propose a new mesh network design algorithm with small computational complexity that the others are solved. The result of the proposed algorithm is better than MENTOR's in total establishment cost, delay time and reliability.

Analysis of Process Characteristics by Single Yarn Production in Ring Spinning (링 정방공정에서 단사제조에 의한 공정특성 분석)

  • Lee, Choon-Gil;Oh, Bong-Hyo;Park, Sung-Diuk
    • Textile Coloration and Finishing
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    • v.9 no.5
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    • pp.1-9
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    • 1997
  • In the single yarn spinning process by the ring spinning system, the finer the fineness of yarn and the lower the twist coefficient, the lower the breaking strength and breaking elongation. The change of yarn specific volume to yarn number agreed with Peirce's formula in the range of Ne 50 to 70, but above that range the values of the experiment are higher than that of the formula. The change of diameter of yarn to the reciprocal of the square root of yarn number agreed with Peirce's formula in the range of under 0.14, but above that value the values of the experiment are higher than that of the formula. In breaking strength variation according to twist constant of single yarn, as the twist coefficient increased, breaking strength increased. At 5.8∼6.0 of twist coefficient the maximum breaking strength was shown, but above that value breaking strength decreased. Breaking elongation also showed a similar tendency. But at 6.0∼6.5 of twist coefficient the maximum breaking elongation was shown. Also spinning tension increased as twist coefficient increased. Twist coefficient, breaking strength and breaking elongation according to the number of coils stayed almost the same. Yarn spinning tension according to the number of coils at the maximum of diameter was the lowest value. The speed of the traveller at the maximum of diameter was the highest value.

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