• 제목/요약/키워드: low-priced

검색결과 231건 처리시간 0.026초

압전 세라믹 필터의 압전 특성에 의한 대역폭 의존성에 관한 연구 (The Frequence Band on the Pizoelectric Characteristic of the Piezoelectric Ceramic Filter)

  • 이수호;석정영;하숙정;류기홍;김한근;류주현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.613-617
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    • 2002
  • The ceramic filters were developed using technology similar to that of quartz crystal and electromechanical filter. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly, a major emhpasis has involved mass production technology, leading to low-priced devices. A typical ceramic filter includes monolithic resonators and capacitors packaged in unique configurations. Nakazawa developed a double-mode resonator as two acoustically coupled single resonators. And he developed 10.7MHz crystal filters using multi-energy trapping mode of thickness shear vibration. He succeeded in realizing a two-pole band pass filter response without external inductance by splitting a dot electrode to creat coupled symmetric and antisymmetric vibration modes. Accordingly, the simulation for ceramic filter were important. So that, this paper were investigated the pass frequency of filter on the electrode length and thickness of ceramic.

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건설기계용 유압실린더 위치 제어시스템의 성능개선에 관한 연구 (A study on performance improvement of position control system in hydraulic cylinder for heavy construction machinery)

  • 한석재;박성환;이진걸
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1450-1454
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    • 1996
  • Even though digital control type high speed solenoid valve is a little inferior to analog control type servo valve and proportional control valve in performance, it is cheap and has secure performance against pollutant and simple control circuit. But high speed solenoid valve is hardly used for heavy machinery instead of servo valve or proportional control valve that is used in severe condition because the valve itself is small capacity and it shows wide dead zone during on-off control and chattering of hydraulic cylinder by chattering of pressure. It is desirable to use low-priced and strong pollutant resistant high speed solenoid valve for obtaining reliability of operation from severe working condition because it isn't necessary to acquire response characteristic of high frequency when we consider the characteristic of heavy machinery operation. In this study, PWM control algorithm for pilot pressure control of large capacity pilot operating valve will be used for precision position control of heavy machinery hydraulic cylinder. Not only cost reduction of main control valve but also high reliability of heavy machinery in severe condition can be obtained by using this pilot operating spool valve with high speed solenoid valve.

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마이크로프로세서에 의한 교근의 휴지기 측정장치의 설계 (Design of Microprocessor-Based Measuring Instrument for the Silent Period of Masseter Muscle)

  • 한현배;로승용;김성환
    • 대한전자공학회논문지
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    • 제22권2호
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    • pp.55-59
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    • 1985
  • 교체에 대한 휴지기 측정은 치과질환의 하나인 TMJ 증후군의 진단에 매우 유용한 방법이다. 본 열구에서는 마이크로프로세서를 이용하여 휴지기를 측정함에 있어서 환자의 충신호에 따른 이득조정이 필요없고 실행시간도 빠르며 상격이 보렴하고 사용이 매우 편리한 변과용 의료장비를 설계하였다. 이 장비를 사용하여 휴지기를 측정한 결과 정상인은 20∼30ms이고 환자의 경우 60ms정도이며 실행시간은 0.5 sec이었다.

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Antioxidant Activity of Sulfated Polysaccharides Isolated from Sargassum fulvellum

  • Choi, Dae-Sung;Athukorala, Yasantha;Jeon, You-Jin;Senevirathne, Mahinda;Cho, Kyun-Rha;Kim, Soo-Hyun
    • Preventive Nutrition and Food Science
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    • 제12권2호
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    • pp.65-73
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    • 2007
  • Sargassum fulvellum, a marine brown alga, is a popular low priced edible plant in Korean markets. The polysaccharide fraction of the alga was separated and investigated for its radical scavenging activities and the results compared with those of commercial fucoidans (Fucus vesiculosus and Undaria pinnatifida), BHA and ${\alpha}$-tocopherol. The polysaccharide fraction of S. fulvellum showed a promising DPPH radical scavenging activity than did other fucoidans. Moreover, the sample exhibited a dose-dependent activity on hydrogen peroxide scavenging activity in the V79-4 cell line. Interestingly, all the tested polysaccharide counterparts were more potent NO. scavengers than were the commercial antioxidants, BHA and ${\alpha}$-tocopherol. The sulfated polysaccharide of S. fulvellum had an approximate molecular weight of 529 kDa and mainly consisted of fucose and galactose, and minor amounts of mannose, rhamnose and xylose.

흙배지의 버섯균사배양 이용 효과 (Effect of Soil Media in Mushroom Mycelial Incubation)

  • 장현유
    • 농촌지도와개발
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    • 제6권2호
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    • pp.141-147
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    • 1999
  • 느타리버섯은 톱밥:미강(80;20, %, v/v)에 황토흙, 밭흙, 논흙을 각각 40% 혼합시 89, 88, 68mm/10일 순, 표고버섯은 톱밥:미강(80;20, %, v/v)에 밭흙, 황토흙, 논흙을 각각 $40{\sim}50%$ 혼합시 74, 71, 68mm/10일 순, 영지버섯은 톱밥:미강(80;20, %, v/v)에 밭흙, 황토흙, 논흙을 각각 $40{\sim}50%$ 혼합시 98, 94, 89mm/10일 순으로 균사생장과 균사밀도가 양호하였다.

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Probiotic bacteria의 생장에 대한 막걸리슬러지의 이용 (Utilization of Makgeolli sludge for growth of probiotic bacteria)

  • 김완섭
    • 농업과학연구
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    • 제38권3호
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    • pp.473-477
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    • 2011
  • A number of health benefits have been claimed for probiotic bacteria such as Bifidobacterium (B) spp. Lactobacillus(L) acidophilus, and Lactococcus(Lc) cremoris. Viability of probiotic bacteria is important in order to provide health benefits. Only a limited culture media for the test purpose of probiotic bacteria are commercially available (MRS broth), but the media for large-scale propagation of viable cells which are able to be used as food additive are not available. The manufacture of a low priced and preferred novel medium for probiotic bacteria was therefore, attempted using whey protein concentrate(WPC) and Makgeolli sludge as a starting material. The effect of WPC and Makgeolli sludge on the growth of four strains (B. bifidum 15696, B. longum 15707, L. acidophilus CH-2, and Lc. cremoris 20076) was investigated. Medium prepared such as WPC, Makgeolli sludge, and WPC+Makgeolli sludge(WPCMs). It was observed that the growth of 4 strains (B. bifidum 15696, B. longum 15707, L. acidophilus CH-2, and Lc. cremoris 20076) was stimulated by Makgeolli sludge, WPC, WPCMs. Especially, Viable cell number of 4 strains in the WPCMs were higher than that of the single media. These result suggest the possibility that Makgeolli and WPC, acts as a growth factor for the growth of probiotic bacteria.

시니어세대의 연령에 따른 실내복 디자인 선호도 및 구매행동 연구 - 50대 이상 중.노년 여성을 중심으로 - (A Study of Senescent Female Consumer's Design Preferences for their Lounge Wear and Buying Behaviors - A Focus on Elderly Women over Fifty -)

  • 정삼호
    • 복식
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    • 제59권4호
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    • pp.143-154
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    • 2009
  • The purpose of this research is to investigate elderly, middle-aged female consumers' design and material preferences for lounge wear and after understanding senescent women's propensity to purchase lounge wear. The subject of research were to those living in the Seoul and capital region and 612, which did not comprise missing values, were collected and used for data analyses. All the age groups including those in their 50s and 60s prefer jacket and pants styles the most and these styles are the most favored as lounge wear as well. Those in their 50s and 60s prefer a round neckline the most while those in their 70s favor a V neckline the most. Analyses of sleeve styles of senescent women show that all the age groups favor a straight set, or a sleeve design, the most. Although the aged people investigated in this research have relatively high purchasing power, it is found that they tend to buy low priced lounge wears. Reviewing all of the above-mentioned results, the prices of garments for senescent people will be set in consideration of their economic level, so that good quality commodities may be produced and sold at different prices.

스페셜 오더 상품과 모바일 SNS 홍보 전략이 브랜드 럭셔리 및 브랜드 관계에 미치는 영향 (Effect of Special Order Products and Mobile SNS Promotions on Perceived Brand Luxury and Brand Relationship)

  • 이계정;이은정
    • 한국의류산업학회지
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    • 제19권4호
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    • pp.411-420
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    • 2017
  • With the increasing popularization of low-priced luxury markets, maintaining the genuine values of luxury has become crucial for luxury fashion brands to attract customers who want exclusivity and rarity. The world-leading luxury fashion houses have employed a variety of experiential marketing strategies like special order product strategies and mobile SNS promotion strategies, yet little research exists on there the strategies actually positively impact brand luxury images and customer attitudes towards the brand. This study empirically analyzed the effects of customer experience of special order products on perceived brand luxury and brand relationship. Furthermore, the study also tested relationships among perceived brand luxury, brand relationship, and brand loyalty. A survey was conducted with Korean female consumers who had purchase experiences of special order products from the brands. We analyzed the data of MTO-experienced respondents due to the lack of respondents who had experienced custom-made product services. The result indicates the significant effect of experience of MTO on brand relationship; however, we found only a partial support for the effect of MTO on brand luxury. Likewise, we found a partial support for the effect of mobile SNS promotion strategies on perceived brand luxury versus full support for the effect on brand relationship.

고주파용 세라믹 필터의 제작을 위한 디자인 해석 (The Design Simulation for Manufacture of High Frequence Ceramic Filter)

  • 이수호;석정영;류기홍;사공건;윤광희;류주현;박창엽
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.418-421
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    • 2001
  • The ceramic filters were developed using technology similar to that of quartz crystal and electromechanical filter. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly, a major emhpasis has involved mass production technology, leading to low-priced devices. A typical ceramic filter includes monolithic resonators and capacitors packaged in unique configurations. Nakazawa developed a double-mode resonator as two acoustically coupled single resonators. And he developed 10.7MHz crystal filters using multi-energy trapping mode of thickness shear vibration. He succeeded in realizing a two-pole band pass filter response without external inductance by splitting a dot electrode to creat coupled symmetric and antisymmetric vibration modes. Accordingly, the simulation for ceramic filter were important. So that, this paper were investigated the pass frequency of filter on the electrode length and thickness of ceramic.

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돌관공사가 안전관리에 미치는 영향 및 예방대책에 관한 연구 (A Study on the Impact to Safety Management by the Speedy Construction Work and the Prevention Measure)

  • 하행봉;방명석
    • 대한안전경영과학회지
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    • 제15권2호
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    • pp.143-149
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    • 2013
  • Recently in the construction business construction companies has been ordered to survive in the terriblly competitive environment. Aa a result, most of the project with low-priced contract needs a speedy progress during all construction period. For the last five years major incident frequently occurs and results in the death of 189 workers at major top 6 construction builders. In most recent 10 years, the cause of major incidents happened in construction company is the speedy construction work that is affecting on the safety management. To prevent these accidents in the speedy construction work, four factors were chosed and analysed such as the personnel/organization, the working budget, the subcontractor selection and the employee motivation. The head office taked the support plan and tested it at the pilot work site. It showed a reduced accident and the harmful factors can be eliminated. It should be able to apply to the field to secure safety and prevent accidents.