• Title/Summary/Keyword: 3DP

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Prioritizing for Failure Modes of Dynamic Positioning System Using Fuzzy-FMEA (Fuzzy-FMEA를 이용한 동적위치제어 시스템의 고장유형 우선순위 도출)

  • Baek, Gyeongdong;Kim, Sungshin;Cheon, Seongpyo;Suh, Heungwon;Lee, Daehyung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.2
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    • pp.174-179
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    • 2015
  • Failure Mode and Effects Analysis (FMEA) has been used by Dynamic Positioning (DP) system for risk and reliability analysis. However, there are limitations associated with its implementation in offshore project. 1) since the failure data measured from the SCADA system is missing or unreliable, assessments of Severity, Occurrence, Detection are based on expert's knowledge; 2) it is not easy for experts to precisely evaluate the three risk factors. The risk factors are often expressed in a linguistic way. 3) the relative importance among three risk factors are rarely even considered. To solve these problems and improve the effectiveness of the traditional FMEA, we suggest a Fuzzy-FMEA method for risk and failure mode analysis in Dynamic Positioning System of offshore. The information gathered from DP FMEA report and DP FMEA Proving Trials is expressed using fuzzy linguistic terms. The proposed method is applied to an offshore Dynamic Positioning system, and the results are compared with traditional FMEA.

A Empirical Study on Determinants Affecting the Participation and Performance of Small and Medium-Size Enterprises in Global Electronic Commerce (해외직구·역직구시장에서 중소기업의 참여와 성과에 영향을 미치는 결정요인에 관한 실증연구)

  • Kim, Chang Bong;Min, Cheol Hong;Park, Sang An
    • International Commerce and Information Review
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    • v.18 no.4
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    • pp.3-29
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    • 2016
  • Recently, the market size of the global electronic-commerce is rapidly growing. The global market size of an overseas direct-purchase is expected to reach 1 trillion won by 2020. This study intends to determine the decision making factors of B2B overseas direct-purchase(DP) and reverse direct-purchase(RDP), and the impact on the vitalization of the small to middle-sized companies'(SMC) overseas DP and RDP. Ultimately, the purpose of this study is to provide a policy insight on the expansion of exports by SMC. For this, we determined the necessary elements for getting good results by Korean SCM in the overseas DP and RDP market through a preceding research based on resource-based theory and industry structure theory. Afterwards, we used the multiple regression model for positive analysis of the survey documents. We were able to confirm through analysis that the company information, logistics delivery, customs process, law and regulations have positive effects on the overseas DP and RDP. This study surveyed the entire overseas DP market, rather than focusing on the cases of harm and responses of the overseas DP, which was the topic for the preceding research, and can be differentiated from the previous study by deducting influence factors for the Korean SMC to succeed in the overseas DP and RDP market. Moreover, the results of this study is meaningful in proposing a strategic direction for the SMC participating in the overseas DP market and the government enacting policies.

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Synthesis and performance assessment of modified epoxy resins containing fatty acid (지방산 변성 에폭시수지 합성과 성능평가)

  • Lee, Dong-Chan;Kim, Jin-Wook;Choi, Joong-So
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.4
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    • pp.634-646
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    • 2016
  • In this work, modified epoxy resins which were well melted in mild solvent were synthesized and solubility assessment was carried out for synthesized epoxy resins. Bisphenol-A type, phenol novolac type and ortho-cresol novolac type epoxy resins were used and fatty acid, dodecyl phenol (DP) and toluene diisocyanate (TDI) were added for synthesis of modified epoxy resins containing fatty acid (MEFA). Composition was epoxy resin/fatty acid = 1.0/0.5 and fatty acid/DP = 0.25/0.25 by equivalent weight and twelve MEFAs were synthesized according to epoxy resins. Viscosity and solubility were measured for twelve MEFAs. As a result, solubility of MEFA was excellent for mild solvent according to increasement of contents of benzene ring, glycidyl group and carbon number of alkyl group. And physical properties were measured for each coating of paints after preparing transparent paints of MEFA to melt well in mild solvent among twelve MEFAs. As a result, they showed an optimal performance on conditions of equivalent ratio of bisphenol-A type epoxy resin/fatty acid/DP/TDI; 1.0/0.25/0.25/0.5 and equivalent ratio of phenol novolac type epoxy resin/fatty acid/DP; 1.0/0.25/0.25 for drying time, adhesion, hardness, impact resistance and alkali resistance.

The effect of the digital manufacturing technique of cantilevered implant-supported frameworks on abutment screw preload

  • Altuwaijri, Shahad Mohammmed;Alotaibi, Hanan Nejer;Alnassar, Talal Mughaileth
    • The Journal of Advanced Prosthodontics
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    • v.14 no.1
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    • pp.22-31
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    • 2022
  • PURPOSE. The purpose of this study was to investigate the misfit and screw preload at the implant abutment connection of implant supported fixed dental prosthesis with cantilever (ICFDP) manufactured using different digital manufacturing techniques and to compare the screw preload before and after cyclic loading. MATERIALS AND METHODS. Mandibular jaw model with four intra-foraminal implants was scanned using digital scanner. Stereolithography file was used to design a framework with nonengaging (NE) abutments and 10 mm cantilever distal to one terminal implant. Five frameworks were constructed using combined digital-conventional techniques (CAD-cast), and five frameworks were constructed using three-dimensional printing (3DP). Additional CAD-cast framework was constructed in a way that ensures passive fit (PF) to use as control. Scanning electron microscope (SEM) measured the implant abutment connection misfit. Sixty screws were used on the corresponding frameworks. Screws were torqued and pre-cyclic loading reverse torque value (RTV) was recorded. Frameworks were subjected to 200,000 loading cycles with a loading point 9 mm from the center of terminal implants adjacent to the cantilever and post-cyclic loading RTVs were recorded. RESULTS. Microscopic readings showed significant differences between frameworks. PF demonstrated the lowest measurements of 16.04 (2.6) ㎛ while CAD-cast demonstrated the highest measurements of 29.2 (3.1) ㎛. In all groups, RTVs were significantly lower than the applied torque. Post-cyclic loading RTV was significantly lower than pre-cyclic loading RTV in PF and 3DP frameworks. Differences in RTVs between the three manufacturing techniques were insignificant. CONCLUSION. Although CAD-cast and three-dimensionally printed (3DP) both produce frameworks with clinically acceptable misfit, 3DP might not be the technique of choice for maintaining screw's preload stability under an aggressive loading situation.

The Control of SFFS in the Office Environments and It's Integration

  • Kim, Jung-Su;Lee, Min-Cheol;Lee, Won-Hee;Kim, Dong-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2164-2169
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    • 2005
  • SFFS(Solid Freeform Fabrication System) can quickly makes models and prototype parts from 3D computer-aided design (CAD) data. Three dimensional printing(3DP) is a kind of the solid freeform fabrication. The 3DP process slices the modeling data into the 50-200um along to z axis. And we pile the powder and make the manufactures. A manufacture is made by the SFFS has the precision of the 50um. Therefore the x-y table of SFFS to move a printhead must be the system that has a high speed and accuracy. So we proposed the SMCSPO algorithm for SFFS. The major contribution is the design of a robust observer for estimating the state and the perturbation of the timing belt system, which is combined with a robust controller. The control performance of the proposed algorithm is compared with PD control by the simulation and the experiment. The control algorithm of the SFFS is presented in the office environment. The system between control system and printhead for the SFFS is also integrated

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On-line signature verification method using Gabor filter (Gabor 필터를 이용한 온라인 서명 검증 기법)

  • 이종현;김성훈;김재희
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.3
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    • pp.129-137
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    • 2004
  • This paper presents a signature verification method that uses Gabor filter in computing similarity between signatures. In computing similarity to compare two on-line signatures, the temporal relationship between two signatures should be computed in advance. However, conventional point matching method using DP(dynamic programming) matching consumes much computation. In this paper, we propose a fast method for computing the temporal relationship between two on-line signatures by using the phase output of Gabor Inter applied on the on-line signature signals. Two similarity measures are defined in the method: Temporal Similarity and Temporally Arranged Feature Profile Similarity. With the proposed method, Ive could compare signatures 30 times faster than conventional method using DP matching.

Adaptive Writeback-aware Cache Management Policy for Lifetime Extension of Non-volatile Memory

  • Hwang, Sang-Ho;Choi, Ju Hee;Kwak, Jong Wook
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.4
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    • pp.514-523
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    • 2017
  • In this paper, we propose Adaptive Writeback-aware Cache management (AWC) to prolong the lifetime of non-volatile main memory systems by reducing the number of writebacks. The last-level cache in AWC is partitioned into Least Recently Used (LRU) segment and LRU using Dirty block Precedence (DP-LRU) segment. The DP-LRU segment evicts clean blocks first for giving reuse opportunity to dirty blocks. AWC can also determine the efficient size of DP-LRU segment for reducing the number of writebacks according to memory access patterns of programs. In the performance evaluation, we showed that AWC reduced the number of writebacks up to 29% and 46%, and saved the energy of a main memory system up to 23% and 49% in a single-core and multi-core, respectively. AWC also reduced the runtime by 1.5% and 3.2% on average compared to previous cache managements for non-volatile main memory systems, in a single-core and a multi-core, respectively.

Multiplex PCR Detection of 4 Events of Genetically Modified Soybeans (RRS, A2704-12, DP356043-5, and MON89788)

  • Kim, Jae-Hwan;Seo, Young-Ju;Sun, Seol-Hee;Kim, Hae-Yeong
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.694-699
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    • 2009
  • A multiplex polymerase chain reaction (PCR) method was developed for the detection of 4 events of genetically modified (GM) soybean. The event-specific primers were designed from 4 events of GM soybean (RRS, A2704-12, DP356043-5, and MON89788). The lectin was used as an endogenous reference gene of soybean in the PCR detection. The primer pair YjLec-4-F/R producing 100 bp amplicon was used to amplify the lectin gene and no amplified product was observed in any of the 9 different plants used as templates. This multiplex PCR method allowed for the detection of event-specific targets in a genomic DNA mixture of up to 1% GM soybean mixture containing RRS, A2704-12, DP356043-5, and MON89788. In this study, 20 soybean products obtained from commercial food markets were analyzed by the multiplex PCR. As a result, 6 samples contained RRS. These results indicate that this multiplex PCR method could be a useful tool for monitoring GM soybean.

Production of Inulo-oligosaccharides from Chicory(Cichorium intybus, L.) with Endo-inulinase from Arthrobacter sp.537 (새로운 endo-inulinase를 이용한 치커리 추출물로부터 Inulo올리고당의 생산)

  • Kang, Su-Il;Kim, Su-Il
    • Applied Biological Chemistry
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    • v.40 no.1
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    • pp.34-38
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    • 1997
  • For the effective production of functional oligosaccharides(DP 3-5) from inulin in chicory extracts, the acid hydrolysis and enzymatic endo-inulinase reaction were compared. Acid hydrolysis was unfavorable ; the content of oligosacharides in total sugar increased to 26.0% for 12 min at $55^{\circ}C$ and 24.6% at 6 min at $65^{\circ}C$ and showed little change for 30 min. The content of high DP(DP 6) decreased from 83.5 to 49.5% and 23.0% for 30 min, repectively. Glucose, fructose and sucrose increased to 24.6% and 50.3%, respectively. Hydrolysis of chicory extracts with purified endo-inulinase from Arthrobacter sp. S37 was carried out at $40^{\circ}C$ and pH 7.5 for 44 hrs. The content of high DP($DP{\geq}6$) in total sugar decreased from 83.5 to 23.0% and that of inulobiose(F2) and DP 3-5 increased to 66.1%. Glucose, fructose and sucrose were not produced. The hydrolysis of chicory extracts without DP 1 and DP 2 with crude or with purified enzyme were also carried out. In contrast to the hydrolysate of crude enzyme, that of purified endo-inulinase did not contain glucose, fructose, sucrose, F2 and 1-kestose(GF2). The content of oligosaccharides in the hydrolysate of the purified endo-inulinase were 79.2%, composed mainly of inulotriose(F3), inulotetraose(F4) and inulopentaose(F5), which shows that the enzymatic hydrolysis using purified endo-inulinase from Arthrobacter sp. S37 is the best method for oligosaccharides production from inulin in chicory extracts.

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Preparation of Shikhae with Starch Hydrolysing Enzymes/Malt Mixture in Tea-bag (전분 분해효소 첨가와 종이봉지를 이용한 식혜의 제조 방법)

  • Yook, Cheol;Hwang, Yoon-Hee;Pek, Un-Hua;Park, Kwan-Hwa
    • Korean Journal of Food Science and Technology
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    • v.22 no.3
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    • pp.296-299
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    • 1990
  • As an improved preparation method of Shikhae, a tea-bag system containing malt and amylolytic enzymes was developed in which extraction of malt enzymes and saccharification occured efficiently. The amylolytic activity of the malt was increased by adding the mixture of ${\alpha}-amylase$, glucoamylase and glucoisomerase. Malt and the mixture of enzymes were placed in tea-bag $(16{\times}20cm)$, extracted in water at $30-40^{\circ}C$ for 1-2 hours and followed by saccharification of the cooked rice at $60-70^{\circ}C$ for 3-4 hours. In the conventional Shikhae, content of maltose was about 50% and that of oligosaccharides larger than trisaccharides was about 40% of total sugar. The content of monosaccharides such as glucose and fructose was about 95% and this improved method would be effective for increasing the sweetness and the monosaccharide contents in the product.

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