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Optimal Culture Conditions for the Shoot Growth of Freesia 'Shiny Gold' during Bioreactor Culture

  • Kang, Ji Su;Jeong, Kyeong Jin;Choi, Youn Jung;Yun, Jae Gill
    • Korean Journal of Plant Resources
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    • v.30 no.6
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    • pp.699-706
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    • 2017
  • For rapid production of freesia 'Shiny Gold' shoots by using a bioreactor, several culture conditions were investigated. Young shoots (< 1 cm) obtained from freesia corm section in vitro were used as plant materials for this experiment. As a basic experimental environment, 20 young shoots were inoculated into a 5 L balloon type bubble reactor which contained 1 L 1/2 strength MS medium supplemented with 30 g sucrose (3%), and the aeration was 0.1 vvm (vessel volumes per minute). The bioreactors were placed in a growth room with $23^{\circ}C$ temperature, 60% relative humidity and $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light condition (16 h/8 h, day/night). The concentrations of MS media were set with 1/4, 1/2, 1 strength, medium volume 10, 20, 40%, sucrose concentration 3, 6, 9%, and aeration 0.1, 0.2, 0.4 vvm. After 4 weeks of cultivation, the growth indexes including the fresh and dry weight, and plant height were evaluated. At the same time, the consumption, pH, and EC of medium were estimated 4 weeks after incubating. The best results were achieved when 40 young shoots were incubated in a bioreactor in which 1 L of 1/2 strength MS medium supplemented with 6% sucrose was used for the rapid production of freesia shoots. The shoots were 17 cm in plant height and 1.0 g in fresh weight only 4 weeks after incubation which could be a good plant material suitable for corm enlargement in vitro. No correlation was observed between the growth of freesia shoots and the consumption, pH or EC of medium.

Dispersion-managed Links with the Irregular Distribution of the Lengths and Dispersion Coefficients of the SMFs and the DCFs (SMF와 DCF의 길이와 분산 계수가 불규칙하게 분포하는 분산 제어 링크)

  • Lee, Seong-Real
    • Journal of Advanced Navigation Technology
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    • v.22 no.3
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    • pp.240-245
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    • 2018
  • A flexible dispersion-managed link configuration is proposed by using single-mode fibers (SMFs) and dispersion-compensating fibers (DCFs) with irregular dispersion coefficients and lengths over all fiber spans for compensating of WDM channels distortion due to the group velocity dispersion and nonlinear effects of optical fibers. The flexibility of link is enabled by artificially distributing of these fibers based on the dispersion coefficients of DCFs in each half transmission section. The simultaneous ascending and descending (AD) distribution of the DCF's coefficients before and after the optical phase conjugator, respectively, best compensates the distorted wavelength division multiplexed signals in the optical link. Therefore, to improve the compensation effect of the distorted WDM channels, AD distribution is needed to choice regardless of fiber lengths and the residual dispersion per span and fiber's dispersion coefficients.

Boundary Layer Correction of Hypersonic Wind-tunnel Nozzle Designed by the Methods of Characteristics (특성곡선 해법 설계 극초음속 노즐의 경계층 보정)

  • Kim, So-Yeon;Kim, Sung Don;Jeung, In-Seuck;Lee, Jong-Kuk;Choi, Jeong-Yol
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.12
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    • pp.1028-1036
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    • 2014
  • A design procedure is established for hypersonic nozzles by using MOC(Method of Characteristics) and CFD. The inviscid nozzle contour is designed by MOC, then BLC(Boundary Layer Correction) is made by evaluating the boundary layer thickness from viscous CFD analysis. By comparing various definitions of the boundary layer thicknesses, it seems that the boundary layer thickness of 95% speed of the maximum value at the cross section satisfies best the design Mach number. Design procedure is as follow; MOC design, grid generation, inviscid analysis, viscous analysis, BLC and viscous analysis for confirmation and post-processing. All procedures are made automatically by using the batch processing.

Experimental Study to Improve the Performance of the Pretensioner for a Passenger Vehicle (자동차용 프리텐셔너의 성능향상을 위한 실험적 연구)

  • Jung, Sung-Pil;Park, Tae-Won;Song, Taeck-Rim
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.2
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    • pp.1-6
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    • 2010
  • This study presents the practical design modification to improve the retracting performance of the pyro-typed high power pretensioner. 3 components of the pretensioner are redesigned and the usefulness of the design modification is verified by the experiment. During the pretensioning process, the gas blast generated from the gunpowder is transferred to the rack-pinion gear through the manifold. The rack-pinion gear is connected with the spool where the webbing is rolled up. According to the rotation of the pinion, the spool is turned and the webbing is winded. To help the gas blast flow well, the shape of the inner cross section of the manifold is changed. The spur gear design program is developed and used to find the best combination of the rack-pinion gear pair to increase the power transmission efficiency. The pinion guide is installed on the spool to prevent the vibration of the pinion. As a result of the experiment, the amount of the web retraction length is increased when every single design modification is applied. Therefore, the retracting performance of the pretensioner is considered to be improved if the presented design modifications are applied.

A study on the optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber (시아노아크릴레이트 진공 훈증법에 의한 잠재지문 현출 최적화에 관한 연구)

  • Yu, Je-Seol;Jung, Jin-Sung;Lim, Seung;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.25 no.3
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    • pp.164-170
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    • 2012
  • Cyanoacrylate fuming mehod is effective for latent fingerprints developing on non-porous surfaces. In this study, we investigated optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber. The effects of temperature, relative humidity, fuming method and processing time were checked throughly. The amount of evaporated cyanoacrylate was increased at higher temperature, but cyanoacrylate polymerization on the fingerprint ridge was best at $30^{\circ}C$. With a relative humidity of 40% to 50% conditions, good quality of fingerprints were developed. If a relative humidity is lower than 30% or higher than 60%, polymerization rate of cyanoacrylate monomers on the fingerprint ridge was decreased. It was identified that application of $OMEGA-PRINT^{TM}$ dispersal pad or cotton ball with sodium hydroxide fuming method in vacuum chamber was more effective than natural fuming method. We found that cyanoacrylate processing time in vacuum chamber did not have more significant than relative humidity.

Occlusion of Patent Ductus Arteriosus in a Chihuahua Dogs Using Amplatzer Vascular Plug though Femoral Vein (동맥관 개존증에 걸린 치와와 개에서 대퇴정맥을 통한 Amplatzer 혈관플러그를 이용한 중재술적 치료)

  • Han, Suk-Hee;Lee, Dong-Gook;Choi, Ran;Suh, Sang-Il;Oh, Yeonsu;Hyun, Changbaig
    • Journal of Veterinary Clinics
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    • v.32 no.3
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    • pp.243-246
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    • 2015
  • A 9 month-old female Chihuahua (weighing 1.5 kg) was referred with loud left basal murmur and exercise intolerance. Diagnostic imaging studies revealed the elongation of left ventricle (LV) with classic triple bumps on the main pulmonary artery, aorta and left atrium on the dorsoventral view of radiograph. Echocardiography revealed patent ductus arteriosus (PDA) duct and continuous turbulent shunt flow (maximal velocity 5.73 m/s) between the aorta and pulmonary artery with left to right direction. The PDA in this dog was successfully closed though femoral vein (transvenous approach) using an Amplatzer$^{(R)}$ vascular plug. To the best of author's knowledge, this is the first case of PDA occlusion treated with vascular plug through femoral vein.

Hybrid (CNC+Laser) process for polymer welding (하이브리드 방식 (CNC+Laser)을 이용한 폴리머용접공정)

  • Yoo, Jong-Gi;Lee, Choon-Woo;Kim, Soon-Dong;Choi, Hae-Woon;Shin, Hyun-Myung
    • Proceedings of the KWS Conference
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    • 2009.11a
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    • pp.4-4
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    • 2009
  • Polycarbonate (PC) and Acrylonitrile Butadiene Styrene (ABS) was welded through a combination of a diode laser and CNC. Laser beam passed the transparent PC and was absorbed in an opaque ABS. Polymers were melted and welded by absorbed and conducted heat. Experiments were carried out by varying working distance from 44mm to 50mm for the focus spot diameter control, laser input power from 10W to 25W, and scanning speed from 100 to 400mm/min. The weld bead size and the specimen cross-section were analyzed, and tensile results were presented through the joint force measurement. With focus distance at 48mm, laser power with 20W, and welding speed at 300mm/min, experimental results showed the best welding quality which bead size was 3.75mm and the shear strength was $22.8N/mm^2$. Considering tensile strength of ABS is $43N/mm^2$, shear strength was sufficient to hold two materials. A single process was possible in CNC machining processes, surface processing, hole machining and welding. As a result, the process cycle time was reduced to 25%. Compared to a typical process, specimens were fabricated in a single process, with high precision. By combining two operations processes developed process gained 50% more efficiency.

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A Study on the Wave Type and the Damage of Hair according to Water content when Heat permanent is treated - Focus on Damaged Hair -

  • Lee, Soon-Hee;Choi, Jung-Myung
    • Journal of Fashion Business
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    • v.12 no.6
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    • pp.11-22
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    • 2008
  • The goal of this study is to provide beauticians with the fundamental material to use effectively heat permanent wave in beauty industry as well as their customer's satisfaction. It carried out an experiment with damaged hair of a woman in her late twenties to investigate the change of physical and morphological characteristics by its water content when performing heat permanent wave. After spreading 0g, 1g, 2g, 3g, and 4g of water on damaged hair respectively, heat permanent wave was treated and the change of hair was observed. The change of physical characteristic was compared through permanent wave form of hair, tensile strength and elongation. The change of morphological characteristic was observed through Scanning Electron Microscope(SEM) and Transmission Electron Microscope(TEM). The result of experiment on the physical specificity revealed that permanent wave form was the most ideal when the water content was 2g, also 3g. Though the materials with much moisture content formed the results were not satisfied. The material with 0g of water content didn't make the wave. In terms of tensile strength and elongation, tensile strength was generally reduced as per the damaged degree of hair. On the contrary, elongation was increased. It observed the changes of morphological characteristic that the damage on hair cuticle was deepen, as its moisture content was decreased, and cuticle's surface was worn away. The observation of fine structure on hair section by transmission electronic microscope also certainly showed the result that damaged hair having experience with chemical treatment had got much damaged to hair cuticle as well as hair cortex. Generally chemical treatment makes hair damaged. Under consideration of this aspect, the ultimate goal of this thesis is to minimize the damage of hair caused by chemical treatment and get the satisfaction on the hair style. According to the result of experiment, the damaged hair whose moisture content was 3g showed the best permanent wave form.

Characteristics of Plasma Electrolytic Oxidation Coatings on Mg-Zn-Y Alloys Prepared by Gas Atomization (가스 분사법으로 제조한 Mg-Zn-Y 합금의 플라즈마 전해 산화 피막 특성에 관한 연구)

  • Chang, Si-Young;Cho, Han-Gyoung;Lee, Du-Hyung;Kim, Taek-Soo
    • Journal of Powder Materials
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    • v.14 no.6
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    • pp.372-379
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    • 2007
  • The microstructure, mechanical and electrochemical properties of plasma electrolytic coatings (PEO) coatings on Mg-4.3 wt%Zn-1.0 wt%Y and Mg-1.0 wt%Zn-2.0 wt%Y alloys prepared by gas atomization, followed by compaction at 320 for 10 min under the pressure of 700 MPa and sintering at 380 and 420 respectively for 24 h, were investigated, which was compared with the cast Mg-1.0 wt%Zn alloy. All coatings consisting of MgO and $Mg_2SiO_4$ oxides showed porous and coarse surface features with some volcano top-like pores distributed disorderly and cracks between pores. In particular, the surface of coatings on Mg-1.0 wt%Zn-2.0 wt%Y alloy showed smaller area of pores and cracks compared to the Mg-4.3 wt%Zn-1.0 wt%Y and Mg-1.0 wt%Zn alloys. The cross section micro-hardness of coatings on the gas atomized Mg-Zn-Y alloys was higher than that on the cast Mg-1.0 wt%Zn alloy. Additionally, the coated Mg-1.0 wt%Zn-2.0 wt%Y alloy exhibited the best corrosion resistance in 3.5%NaCl solution. It could be concluded that the addition of Y has a beneficial effect on the formation of protective and hard coatings on Mg alloys by plasma electrolytic oxidation treatment.

A Study on the Effective Design for Figure of Middle Aged Women (중년여성의 체형에 적합한 의복형태와 면분할 및 배치 방안에 관한 연구)

  • 김옥진
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.7
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    • pp.1173-1183
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    • 1997
  • In order to flatter the figures of average middle aged women by determining harmonious proportions for their costume forms, this study evaluates effects of varying design details of jackets(coats) with blouses and slacks using a ranking test and paired comparisons test. The result from clothing design C-2 which has the best design effect were as follows; 1. In order to look taller, the jacket(coats) is divided vertical long line and it has the emphasis point close to the face. 2. In order to make shoulder width look wider, armhole seam line attached 1-2 cm from the shoulder point. 3. In order to make chest width look slimmer, division was made up of a tailored collar with a deep V-neckline. 4. In order to make waist circumference look slimmer, the jacket has more fitted waist line than loosed it and tailored collar with a deep V-neckline. 5. In the case of the division of upper and lower garments, when the division was closer to the golden section, i.e., when the jacket hemline is hipline and slacks length is the heel excluded length of shoe heels, the overall appearance was better. 6. The V-neckline looked better, when it was cut along a long acute angle to the waist line. Because of dividing along above factors 1-6 i.e., clothing design C-2 was overall harmonious. Appropriate division of costume forms made for an aesthetic composition, which flattered the body types of middle aged women and presented harmonious, beautiful costume design effects. It made the women look taller, slim and balanced, and highlighted middle aged women's sense of beauty.

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