• 제목/요약/키워드: disadvantageous

검색결과 225건 처리시간 0.032초

명반석을 이용한 알루미나 시멘트의 제조(I) (Monocalcium Aluminate의 합성) (Studies on Alumina Cement from Alunite (I) (Synthesis of monocalcium aluminate))

  • 한기성
    • 한국세라믹학회지
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    • 제15권4호
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    • pp.199-204
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    • 1978
  • In the present investigation, refined alumina obtained from alunite locally available was used as a aluminous source to synthesize monocalcium aluminate $(CA)_3$ the major mineral constituent of alumina cement. The influence of $SiO_2$ and $Fe_2O_3$ contents on the formation of monocalcium aluminate was studied by X-ray diffraction analysis mainly. About 0.8-1.0 of $Al_2O_3/C_3O$ mol ratio and less than 4 percent of $SiO_2$ were desirable for the effective formation of CA. The small amount of alkali and sulphur contents contained in refined alumina from alunite as the impurities were affected to form $C_4A_3S$ and $C_3S_2$, disadvantageous compounds for the alumina cement, therefore the impurities should be restricted in minimum content as possible.

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레그 션트저항을 이용한 2상 유도전동기의 상전류 복원 방법 (Phase Current Reconstruction Method of 2-Phase Induction Motor using Leg-Shunt Resistors)

  • 김동기;윤덕용
    • 전기학회논문지
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    • 제64권8호
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    • pp.1186-1192
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    • 2015
  • This paper proposes an economical method that the phase currents can be measured and reconstructed by means of the leg-shunt resistors in the 3-leg 2-phase vector-controlled inverter for 2-phase induction motor. In general, the phase currents of 2-phase induction motor have been measured using two Hall current sensors. However, because Hall current sensors are expensive, economically disadvantageous to apply in low power applications. The proposed method is verified by computer simulations and experiments to show the good performance of the vector control.

국내외 제조업체 슬림커패시터의 비교분석 (The Comparison Analysis for Foreign and Domestic Slim Capacitors)

  • 임창근;김종민;김강동;박정원
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제12권1호
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    • pp.25-33
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    • 2012
  • As to display products are made slim, the diameter of aluminum electrolytic capacitor is smaller and the length is longer to be fitted in. These small diameter and long length are pointed as the disadvantageous design factors of the capacitor's life cycle. So, the most electronic makers want to use proven capacitors (or well-known) to secure reliability of the electric products. In this study, we carried out the comparison analysis with two domestic capacitors and one foreign made capacitor. We designated separators, rubber breather and debris as the main factors that effect on the lifetime of capacitors. From the comparison results, we suggested the improvement points of the aluminum electrolytic capacitor.

Biological Image Edge Extraction Based on Adaptive Beamlet Transform

  • Nguyen, Van Hau;Woo, Kyung-Haeng;Choi, Won-Ho
    • 융합신호처리학회논문지
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    • 제12권2호
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    • pp.83-90
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    • 2011
  • In cell biology area, microscopy enables detecting objects inside cells that are stained or fluorescently tagged. It is disadvantageous for observing these objects because of the noisy characteristics of their environmental surrounding. In this paper, a framework is proposed to increase the throughput and reliability for analysis of these images. First, we apply adaptive beamlet transform to extract edges meaningfully followed by orientation, location, and length in different scales. Then, a post-process is implemented to extend and map them onto original image. Our proposed scheme is compared with Canny edge detector and conventional beamlet transform from four evaluation aspects. It produces better results when experiments are conducted on real images. Much better results for observing internal parts make this framework competitive for analysis of cell images.

Chemometric A spects of Sugar Profiles in Fruit Juices Using HPLC and GC

  • 윤정현;김건;이동선
    • Bulletin of the Korean Chemical Society
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    • 제18권7호
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    • pp.695-702
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    • 1997
  • The objective of this work is to determine the sugar profiles in commercial fruit juices, and to obtain chemometric characteristics. Sugar compositions of fruit juices were determined by HPLC-RID and GC-FID via methoxymation and trimethylsilylation with BSTFA. The appearance of multiple peaks in GC analysis for carbohydrates was disadvantageous as described in earlier literatures. Fructose, glucose, and sucrose were major carbohydrates in most fruit juices. Glucose/fructose ratios obtained by GC were lower than those by HPLC. Orange juices are similar to pineapple juices in the sugar profiles. However, grape juices are characterized by its lower or no detectable sucrose content. In addition, it was also found that unsweeten juices contained considerable level of sucrose. Chemometric technique such as principal components analysis was applied to provide an overview of the distinguishability of fruit juices based on HPLC or GC data. Principal components plot showed that different fruit juices grouped into distinct cluster. Principal components analysis was very useful in fruit juices industry for many aspects such as pattern recognition, detection of adulterants, and quality evaluation.

단일 엣지를 이용한 깊이 정보에 관한 연구 (A Study on the Depth Map using Single Edge)

  • 김영섭;송응열
    • 반도체디스플레이기술학회지
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    • 제9권2호
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    • pp.123-126
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    • 2010
  • An implementation of modified stereo matching using efficient belief propagation (BP) algorithm is presented in this paper. We do recommend the use of the simple sobel, prewitt edge operator. The application of B band sobel edge operator over image demonstrates result with somewhat noisy (distinct border). When we adopt the only MRF + BP algorithm, however, borders cannot be distinguished due to that the message functions in the BP algorithm is just the mechanism which passes energy data to the only large gap of each Message functions In order to address the abovementioned disadvantageous phenomenon, we use the sobel edge operator + MRF + BP algorithm to distinguish the border that is located between the similar message data. Using edge information, the result shows that our proposed process diminishes the propagation of wrong probabilistic information. The enhanced result is due to that our proposed method effectively reduced errors incurred by ambiguous scene properties.

SSD를 위한 최적화 파일시스템 (An Optimized File System for SSD)

  • 박제호
    • 반도체디스플레이기술학회지
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    • 제9권2호
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    • pp.67-72
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    • 2010
  • Recently increasing application of flash memory in mobile and ubiquitous related devices is due to its non-volatility, fast response time, shock resistance and low power consumption. Following this trend, SSD(Solid State Disk) using multiple flash chips, instead of hard-drive based storage system, started to widely used for its advantageous features. However, flash memory based storage subsystem should resolve the performance bottleneck for writing in perspective of speed and lifetime according to its disadvantageous physical property. In order to provide tangible performance, solutions are studied in aspect of reclaiming of invalid regions by decreasing the number of erasures and distributing the erasures uniformly over the whole memory space as much as possible. In this paper, we study flash memory recycling algorithms with multiple management units and demonstrate that the proposed algorithm provides feasible performance. The proposed method utilizes the partitions of the memory space by utilizing threshold values and reconfigures the management units if necessary. The performance of the proposed policies is evaluated through a number of simulation based experiments.

1-Piece 알루미늄 도어 인너 냉간-열간 복합 성형공정 개발 (Development of the Hybrid Cold-Hot Stamping Process for the 1-Piece Aluminum Door Inner Part)

  • 남성우;배기현
    • 소성∙가공
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    • 제30권5호
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    • pp.242-246
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    • 2021
  • Aluminum alloy sheet is being applied to automobiles continuously for the purpose of reducing car body weight. However, due to low formability, there's a limit to application of products with a deep forming depth such as door inner parts. Therefore, the difficult-to-form parts are mainly segmented formed then joined together, which is also disadvantageous as it increases the cost of manufacturing. This study proposes a hybrid cold-hot stamping method for the 1-piece door inner part to reduce cost. To design the stamping process, numerical simulation method is established by using the temperature-dependent mechanical properties of AA6016. The formability according to the hybrid cold-hot stamping method is evaluated using numerical analysis. The suitability of the proposed stamping method is then verified through the stamping tryout.

The Linkage Between Issue Ownership Perception and Campaign Advertising: A Case Study of the 2012 Taiwan Presidential Election

  • Yu, Eric Chen-hua;Hsu, Pei-chen
    • Asian Journal for Public Opinion Research
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    • 제7권1호
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    • pp.23-39
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    • 2019
  • Assuming that a political party has a strong incentive to gain votes via issue setting as part of its campaign strategy, this study utilized a Web experimental survey to explore the extent to which three issue-related campaign advertising strategies - namely, issue ownership, issue convergence, and issue trespassing - affected voters' perceptions toward parties' issue-handling capabilities. Our empirical results show that issue ownership perceptions exist in Taiwan. In the 2012 Taiwan presidential election, as issue ownership advertisements may reinforce voters' beliefs regarding parties' issue-handling capabilities, issue trespassing advertising may improve a party's image on the disadvantageous issue dimension. At least our data shows that the Kuomintang's (KMT) advertisements have both effects.

ATYPICAL EMPLOYMENT IN TAIWAN'S CONSTRUCTION INDUSTRY

  • C.F. Huang;J.H. Chen;J.Z. Lin
    • 국제학술발표논문집
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    • The 2th International Conference on Construction Engineering and Project Management
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    • pp.601-610
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    • 2007
  • Responding to the fierce market competition and trying to cut personnel costs, the construction industry in Taiwan is adopting atypical employment in human resource. To discover this trend, this study employed a questionnaire survey to investigate the current use of atypical employment by domestic contractors and its possible impacts on the industry. According to the 103 returned valid questionnaires, 40.8% of the respondent contractors have applied some atypical employment types in recent three years and most of them used fixed-term employment. The major reasons the contractors used atypical employees are to reduce personnel costs, to deal with business fluctuations and to streamline personnel. According to the respondents, there is no significant difference between the advantages and disadvantages of using a large number of atypical employees in the short term. However, in the long term, atypical employment is generally more disadvantageous than advantageous.

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