• Title/Summary/Keyword: RP

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Benchmark Study of Rapid Prototyping Processes and the Development of Decision-support System to Select Appropriate RP Process and Machine (쾌속조형 공정 비교실험 및 공정 선정에 관한 연구)

  • Yi Il Lang;Chung Il Yong;Choi Byung Wook;Keum Young Tag
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.11 s.176
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    • pp.202-209
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    • 2005
  • In this paper, benchmark tests of Rapid Prototyping(RP) are presented to evaluate characteristics of various RP Systems and Processes, and several decision-support systems are developed to select RP Machine/Process suitable to user's requirements. Results of the RP benchmark tests are applied to the recently developed RP machines for the purpose of analyzing attributes such as dimensional accuracy, surface roughness, build cost, build time, and etc. Decision-making support systems are also developed, which contain not only new LCE (Linear Confidence Equation) algorithm but also modified PRES and MDS algorithm. Those algorithms are proved to be effective in that reasonably acceptable results are obtained on several cases of different inputs.

Development of an Expert System for Rapid Prototyping Machine Selection (쾌속조형장비 선정을 위한 전문가시스템 개발)

  • 정일용;이일랑;최병욱
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.632-635
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    • 2002
  • There are more than five dozen different RP(rapid prototyping) systems in the world and they are fairly expensive. All those systems have different capabilities and requirements in that each of them gives different tolerance, application field and part strength, etc. This situation may cause a problem of selecting an appropriate RP system. This paper presents an expert system, utilizing an algorithm that is composed up of rules to derive recommendations and answers to queries of the RP users. The expert system incorporates RP machines commercially available and adopts multi-selection criteria, namely, machine price, accuracy, build size, adopted process, etc. In the expert system, forward reasoning method is adopted and external spreadsheet for sub-data of the RP systems is used. The rules and knowledge are obtained from interviews and discussions with RP vendors and users, appropriate research publications and other reference materials.

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Development of Translucent RP Material by Post-processing: Case Study of FDM (후가공을 통한 반투명 RP 재료의 개발: FDM의 예)

  • Jeong, Woo-Byok;Lee, Sun-Young;Ahn, Sung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.9
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    • pp.1524-1530
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    • 2003
  • Translucent plastics are commonly used in packaging of mechanical and/or electrical components. Although Rapid Prototyping(RP) provides prototypes of various materials, translucent RP parts are not readily available from most RP processes. ABSi is one of the ABS materials available for Stratasys' FDM process, and the material had potential to be translucent. In this paper, two post-processing techniques were applied in order to increase optical transmissivity of the parts made of FDM's ABSi. First, elevated temperature condition was applied resulting in increased transmissivity while dimensional shrinkage was observed. Second, resin infiltration and surface sanding provided up tp 16 % transmissivity without shrinkage. These post-processes can be selectively applied to increase transmissivity of ABSi parts. Thus, translucent FDM part can be fabricated from regular FDM process followed by the post-processes developed in this study.

Purification of 4-Methylthio-3-butenyl isothiocyanate the Pungent Principle in Radish Roots by RP-HPLC (RP-HPLC법에 의한 무우의 매운 성분인 4-methylthio-3-butenyl isothiocyanate의 분리 및 정제)

  • Kim, Mee-Ree;Rhee, Hei-Soo
    • Korean journal of food and cookery science
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    • v.2 no.2
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    • pp.16-20
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    • 1986
  • The major pungent component from Korean radish roots was purified by reverse phase high performance liquid chromatography (RPHPLC), and characterized as 4-methylthio-3-butenyl isothiocyanate on the basis of the sensory test (pungency), UV spectrum and mass spectrum analysis. The purified isothiocyanate moved as a single peak(retention time, 5.2 min) in RP-HPLC analysis, and as a single spot(Rf, 0.9) in TLC analysis.

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The impact of the duration of retained placenta on postpartum diseases and culling rates in dairy cows

  • Hur, Tai-Young;Jung, Young-Hun;Kang, Seog-Jin;Choe, Chang Yong;Kim, Ui-Hyung;Ryu, Il-Sun;Son, Dong-Soo;Park, Sung-Jai;Kim, Ill-Hwa
    • Korean Journal of Veterinary Research
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    • v.51 no.3
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    • pp.233-237
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    • 2011
  • The objective of this study was to evaluate the duration of retained placenta (RP) on postpartum diseases and culling in dairy cows. Data were collected from 456 Holstein cows between 2008 and 2010. RP (${\geq}$ 24 h after parturition) and postpartum diseases were diagnosed by farm managers and a veterinarian according to standardized definitions. The overall incidence rate of RP was 14.0%, and the incidence rate of RP with fourth and higher parity was two times that of cows having offspring for the first time. The duration of RP was 2 to 15 days with a mean of 6.8 days, except for cases of fourth and higher parity which had a mean of 10.5 days. A total of 63% of cows with RP had postpartum diseases. Among the cows diagnosed with RP, 23.4% developed metritis, and of those, 35.3% developed endometritis or pyometra. A total of 25% (n = 16) cows with RP were culled within 60 days in milk (DIM) and of those culled, 75% (n = 12) had postpartum diseases. These results suggest that RP increases the risk of postpartum diseases such as metritis and mastitis and is a culling hazard up to 60 DIM.

Anti-Oxidative Activity of Pectin and Its Stabilizing Effect on Retinyl Palmitate

  • Ro, Jieun;Kim, Yeongseok;Kim, Hyeongmin;Jang, Soung Baek;Lee, Hyun Joo;Chakma, Suharto;Jeong, Ji Hoon;Lee, Jaehwi
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.3
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    • pp.197-201
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    • 2013
  • The purpose of this study was to examine the anti-oxidative activity of pectin and other polysaccharides in order to develop a cosmeceutical base having anti-oxidative effects towards retinyl palmitate (RP). The anti-oxidative stabilizing effects of pectin and other polysaccharides on RP were evaluated by DPPH assay and then the stabilizing effect of pectin on RP was examined as a function of time. Among the polysaccharides we examined, pectin exhibited a considerably higher anti-oxidative activity, with an approximately 5-fold greater DPPH radical scavenging effect compared to other polysaccharides. The DPPH radical scavenging effect of pectin increased gradually with increasing concentrations of pectin. At two different RP concentrations, 0.01 and 0.1% in ethanol, addition of pectin improved the stability of RP in a concentration dependent manner. The stabilizing effect of pectin on RP was more effective for the lower concentration of RP (0.01%, v/v). Further, degradation of RP was reduced following the addition of pectin as measured over 8 hours. From the results obtained, it can be suggested that pectin may be a promising ingredient for cosmeceutical bases designed to stabilize RP or other pharmacological agents subject to degradation by oxidation.

Performance Analysis of Virtual Conference System in the IPv6 Multicast Network (IPv6 멀티캐스트 네트워크에서 가상 학술회의 시스템의 성능 분석)

  • Eom, Tai-Rang;Do, Jin-Sook;Lee, Kyung-Geun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.1B
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    • pp.45-54
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    • 2003
  • In the Protocol-Independent Multicast Sparse Mode(PIM-SM), we need a careful selection scheme for the Rendezvous Point(RP) which influences much on the QoS due to the delay among multicast group members and packet loss The QoS based RP selection schemes choose RPs which satisfy the restriction conditions such as bandwidth, delay, and other QoS parameters In this paper, we propose a new RP selection scheme which is a variation of the group-based RP selection scheme The new algorithm, MCT(Maximum Cross Tree), is implemented by taking advantages of the topology-based selection scheme and the group-based selection scheme as well In order to verify the proposed algorithm, we first measure the multicast traffic data of the Virtual Conference System implemented on the IPv6 network via KOREN, then expand the results to two types of network models and analyze the performance by computer simulation.

Quality Characteristics of Iced Cookies Containing Freeze-Dried Yellow and Red Onion Powder (동결 건조 황색 양파 분말과 자색 양파 분말을 첨가한 냉동 쿠키의 품질 특성)

  • Lee, Jeong-Ok;Lee, Seong-A;Kim, Kyoung-Hee;Yook, Hong-Sun
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.5
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    • pp.766-772
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    • 2008
  • The objective of this investigation was to develop iced cookies with freeze-dried yellow onion powder (YP) and red onion powder (RP) at composition levels of 0, 1, 3, 5 and 10%. The moisture (13.61%) and crude ash contents (3.43%) of YP was higher than RP, while the crude protein (7.58%) and crude fat contents (0.65%) of RP was higher than YP. Freeze-dried YP showed a higher lightness and yellowness value compared to RP, because of the unique color of the onion. The browning index was lower in YP. The pH of the dough significantly decreased by addition of onion powder, while the density of the dough was significantly increased in RP samples than the others. The iced cookies showed a lower lightness value, and a higher redness value with increase of onion powder contents. Hardness of YP cookies up to 5% and RP cookies up to 3%, were lower compared to the control. With regards to the sensory characteristics, $3{\sim}5%$ YP cookies and 3% RP cookies were more acceptable than the others. As a result, the optimal ratio of freeze-dried YP and RP iced cookies were calculated at 5% YP and 3% RP levels.

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Hair Growth-promoting Effect of Resina Pini and Its Main Constituent, Abietic Acid, in Mouse Model of Alopecia (탈모마우스모델에서의 송지추출물 및 그 성분인 아비에트산의 모발성장효과)

  • Park, Gunhyuk;Kim, Yong-ung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.3
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    • pp.203-209
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    • 2016
  • Recently, increased attention has been directed toward medicinal extracts and their active ingredients as potential new drug candidates for androgenic alopecia. Resina Pini (RP), a resinous exudation obtained from Pinus sp. (Pinaceae), has been used as a traditional medicine for the treatment of infection, pain related to dental caries, and periodontal disease. Previously, we suggested that RP and its main constituent, abietic acid (abieta-7,13-dien-18-oic acid; AA), may play important roles against androgenic alopecia as $5{\alpha}$-reductase inhibitors. However, to date, there is no evidence that AA has hair growth-promoting effects in vivo. In this study, we found that 10 ~ 300 mg/kg RP and 3 ~ 30 mg/kg AA significantly promoted hair growth in a C3H/HeN mouse model of alopecia. To our knowledge, this is the first report of the hair growth-promoting effects of RP and AA in vivo. From these results, RP and its main constituent AA can promote hair growth in mouse by inhibiting $5{\alpha}$-reductase activity and may be effective alternative therapies for androgenic alopecia.

Ginsenoside Rp1, a Ginsenoside Derivative, Blocks Promoter Activation of iNOS and COX-2 Genes by Suppression of an IKKβ-mediated NF-κB Pathway in HEK293 Cells

  • Shen, Ting;Lee, Jae-Hwi;Park, Myung-Hwan;Lee, Yong-Gyu;Rho, Ho-Sik;Kwak, Yi-Seong;Rhee, Man-Hee;Park, Yung-Chul;Cho, Jae-Youl
    • Journal of Ginseng Research
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    • v.35 no.2
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    • pp.200-208
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    • 2011
  • Ginsenoside (G) $Rp_1$ is a ginseng saponin derivative with anti-cancer and anti-inflammatory activities. In this study, we examined the mechanism by which G-$Rp_1$ inhibits inflammatory responses of cells. We did this using a strategy in which DNA constructs containing cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) promoters were transfected into HEK293 cells. G-$Rp_1$ strongly inhibited the promoter activities of COX-2 and iNOS; it also inhibited lipopolysaccharide induced upregulation of COX-2 and iNOS mRNA levels in RAW264.7 cells. In HEK293 cells G-$Rp_1$ did not suppress TANK binding kinase 1-, Toll-interleukin-1 receptor-domain-containing adapter-inducing interferon-${\beta}$ (TRIF)-, TRIF-related adaptor molecule (TRAM)-, or activation of interferon regulatory factor (IRF)-3 and nuclear factor (NF)-${\kappa}$B by the myeloid differentiation primary response gene (MyD88)-induced. However, G-$Rp_1$ strongly suppressed NF-${\kappa}$B activation induced by I${\kappa}$B kinase (IKK)${\beta}$ in HEK293 cells. Consistent with these results, G-$Rp_1$ substantially inhibited IKK${\beta}$-induced phosphorylation of $I{\kappa}B{\alpha}$ and p65. These results suggest that G-$Rp_1$ is a novel anti-inflammatory ginsenoside analog that can be used to treat IKK${\beta}$/NF-${\kappa}$B-mediated inflammatory diseases.