• Title/Summary/Keyword: 4,4'-DDS

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An effect of immediate dentin sealing on the shear bond strength of resin cement to porcelain restoration

  • Choi, Yu-Sung;Cho, In-Ho
    • The Journal of Advanced Prosthodontics
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    • 제2권2호
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    • pp.39-45
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    • 2010
  • PURPOSE. The aim of this study was to determine differences in shear bond strength to human dentin using immediate dentin sealing (IDS) technique compared to delayed dentin sealing (DDS). MATERIALS AND METHODS. Forty extracted human molars were divided into 4 groups with 10 teeth each. The control group was light-cured after application of dentin bonding agent ($Excite^{(R)}$ DSC) and cemented with $Variolink^{(R)}$. II resin cement. IDS/SE (immediate dentin sealing, $Clearfil^{TM}$ SE Bond) and IDS/SB (immediate dentin sealing, $Adapter^{TM}$ Single Bond 2) were light-cured after application of dentin bonding agent ($Clearfil^{TM}$ SE Bond and $Adapter^{TM}$ Sing Bond 2, respectively), whereas DDS specimens were not treated with any dentin bonding agent. Specimens were cemented with $Variolink^{(R)}$. II resin cement. Dentin bonding agent ($Excite^{(R)}$. DSC) was left unpolymerized until the application of porcelain restoration. Shear strength was measured using a universal testing machine at a speed of 5 mm/min and evaluated of fracture using an optical microscope. RESULTS. The mean shear bond strengths of control group and IDS/SE group were not statistically different from another at 14.86 and 11.18 MPa. Bond strength of IDS/SE group had a significantly higher mean than DDS group (3.14 MPa) (P < .05). There were no significance in the mean shear bond strength between IDS/SB (4.11 MPa) and DDS group. Evaluation of failure patterns indicates that most failures in the control group and IDS/SE groups were mixed, whereas failures in the DDS were interfacial. CONCLUSION. When preparing teeth for indirect ceramic restoration, IDS with $Clearfil^{TM}$ SE Bond results in improved shear bond strength compared with DDS.

Variety of Food Choices is Associated with the Nutritional Quality of Diets of College Students in Korea

  • Kye, Seung-He;Suh, Hee-Jae;Kim, Bok-Hee
    • Preventive Nutrition and Food Science
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    • 제10권4호
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    • pp.364-371
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    • 2005
  • This study was performed to evaluate effects of dietary variety scores (DVS) and dietary diversity scores (DDS) on the nutritional quality of the diets of Korean college students, and to examine the association between food group intake patterns and nutritional adequacy. This study examined the relationship of dietary diversity scores (DDS), dietary variety scores (DVS), and food group intake patterns with nutrient intakes using 24-hour recall data (n=.358). The .DDS was calculated from the sum of each of the five food groups consumed as a score of 'I'. DVS was determined by counting the number of food items consumed daily. Food group intake patterns were expressed with the presence or omission of five major food groups-dairy, meat, grain, fruit, and vegetable. The four most prevalent food group patterns and the proportion of the population reporting them were as follows; no dairy and fruit, $23\%;\;no\;dairy,\;20\%;$ no dairy, meat, and fruit, $15\%$; all food groups, $14\%$. Even though the DDS or DVS was higher, the majority of this study population failed to meet the Korean RDA for calcium in both genders and iron in women. Higher DVS scores $(\geq31)$, within all DDS groups, were associated with the largest proportion of individuals consuming more than $75\%$ of the Korean RDA for selected nutrients. The consistency of these results indicates that screening diets to evaluate the overall dietary variety and variety among the major food groups including food group intake patterns provide meaningful information about their quality.

사물인터넷의 양방향 데이터/이벤트/서비스 연동을 위한 지그비 어댑터 (Zigbee Adaptor for Two-way Data/Event/Service Interoperation in Internet of Things)

  • 백문기;임형준;이규철
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제3권4호
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    • pp.107-114
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    • 2014
  • 사물인터넷(Internet of Things) 환경의 사물들은 네트워크를 통해 정보를 교환하여 다양한 서비스가 이루어진다. 사물인터넷을 구성하는 WSN(Wireless Sensor Network)은 무선 센서 노드를 물리적인 공간에 배치하여 구성된 네트워크로 사물의 식별, 센싱, 통신 등의 기술이 더해져 다양한 목적으로 운용된다. 대표적으로 저가 저전력 장치들로 구성된 지그비(Zigbee) 네트워크는 지역 모니터링 및 원격 장치제어에 활용된다. 다양한 WSN으로 구성된 사물인터넷은 네트워크 간 통신 규약 및 데이터 표현이 상이하여 상호운용에 제약이 있지만 실시간 통신 미들웨어 표준인 DDS(Data Distribution Service)를 통해 이질적인 네트워크 간 상호연결 및 정보교환이 가능하다. 본 논문은 지그비 네트워크와 사물인터넷의 다른 네트워크 간 양방향 데이터/이벤트/서비스 연동을 위한 지그비 어댑터 설계를 다룬다. DDS 기반의 지그비 어댑터는 지그비 표준을 따라 지그비 네트워크와 통신하고 다양한 구성요소 간 유기적인 동작으로 지그비 네트워크와 사물인터넷의 다른 네트워크 간 상호운용을 가능케 한다.

인터넷 영양교육에 참여한 전국 대학생의 식품섭취 및 다양성에 관한 평가 (Regional Differences in Food Intake and Diversity among Korean College Students of a Nutrition Education Course through the Internet)

  • 이정희;장경자
    • 대한지역사회영양학회지
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    • 제8권1호
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    • pp.41-52
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    • 2003
  • The purpose of this study was to evaluate the diversity of food intake among Korean college students of a nutrition education course through the internet. Subjects were 796 nation-wide college students (male 278, female 518). A dietary survey collected from 3 day-recalls were analyzed by the Computer Aided Nutritional Analysis Program. Diet variety was assessed by DDS (dietary diversity score), MBS (meal balance score), and DVS (dietary variety score). The foods consumed in largest amounts were rice (54.42 g), citrus fruit (36.41 g) and milk (30.91 g). The foods consumed most frequently were rice (65.28%), garlic (63.65%) and salt (63.64%). The average food intake was 1325.3 g (male 1420.6 g, female 1274.1 g), with vegetable and animal food comprising 78.5% and 21.5% of total food intake, respectively. The consumption of the major five food groups comprised DDS, and 66.0% (male 56.1%, female 71.3%) of subjects had a DDS of 5 and 27.4% (male 33.5%, female 24.1%) of subjects had a DDS of 4..Groups most frequently missed were dairy products (56.5%) and fruits (41.6%). The average of MBS were 10.88 (11.61 in Seoul, 11.03 in Kyungsang, 10.88 in Chungcheong, 10.85 in Incheon, 10.57 in Kyunggi) in male and 11.08 (11.47 in Kyungsang, 11.20 in Seoul, 11.18 in Kyunggi, 10.82 in Chungcheong, 10.64 in Incheon) in female. Male students in Seoul (18.2) and female students in Kyungsang (18.6) had the greater number of consumed food items. Subjects who had higher DDS had significantly higher DVS (p < 0.001). Based on these results, the food intake of the subjects regarded as not adequate, especially with regards to the dairy and fruit groups. Considering their nutritional characteristics, dietary guidelines as well as education should be made to improve the food intake and include various foods in their diet.

키토산 나노 입자를 이용한 약물전달시스템

  • 권익찬;김광명;김성원;정혜선;정서영
    • 한국고분자학회지:고분자과학과기술
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    • 제15권4호
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    • pp.396-401
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    • 2004
  • 약물전달시스템 (DDS, drug delivery system)이란 기존 약물의 부작용을 최소화하고 약물이 가지고 있는 효능 및 효과를 최적화시켜 질병치유에 필요한 최소의 약물을 효과적으로 전달하기 위한 제형으로 정의될 수 있다. DDS 분야는 저비용과 짧은 개발기간으로 기존 약물의 새로운 제형개발을 가능하게 함으로써 차세대 바이오산업의 핵심으로 인식되고 있다.(중략)

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반응성 열가소성 수지로 개질된 TGDDM/DDS 시스템의 Cure Kinetics (Cure Kinetics of amine-cured tetraglycidyl-4,4'-diaminodiphenylmethane epoxy blends with a new polyetherimide)

  • 황승철;이정훈;김동현;김원호;김민영
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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    • pp.214-217
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    • 2004
  • The cure kinetics of blends of epoxy(tetraglycidyl-4,4'-diaminodiphenylmethane ; TGDDM)/curing agent(diaminodiphenyl sulfone ; DDS) resin with amine terminated polyetherimide-CTBN-amine terminated polyetherimide triblock copolymer(ABA) were studied using differential scanning calorimetry under isothermal conditions to determine the reaction parameters such as activation energy and reaction constants. By increasing the amount of ABA in the blends, the final cure conversion was decreased. Lower values of the final cure conversions in the epoxy/ABA blends indicated that ABA hinders the cure reaction between the epoxy and curing agents. 1be value of the reaction order, m, for the initial autocatlytic reaction was not affected by blending ABA with epoxy resin, and the value was approximately 1.0. The value of n for the nth order component in the autocatalytic analysis was increased by increasing the amount of ABA in the blends, and the value increased from 2.0-3.4. A diffusion controlled reaction was observed as the cure conversion increased and the rate equation was successfully analyzed by incorporating the diffusion control term for the epoxy/DDS/ABA blends.

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해외학술지 원문제공서비스의 경제적 가치 평가 방법론 및 모델 개발 (Development of an Economic Valuation Methodology and Model for the DDS of Foreign Journals)

  • 정영미
    • 정보관리학회지
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    • 제25권4호
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    • pp.245-267
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    • 2008
  • 본 연구는 인쇄형 해외학술지 원문제공서비스(DDS)의 경제성을 분석하기 위해 이용자 기반의 경제적 가치 평가 방법론 및 모델을 개발하고자 하였다. 본 연구를 위해 K기관의 구독중인 해외학술지 원문제공서비스의 데이터 중 일부가 분석을 위해 사용되었고 K기관 원문제공서비스 이용자를 대상으로 웹 서베이를 실시하였다. 해외학술지 원문제공서비스의 경제적 가치는 사용가치, 비사용가치, 그리고 기대가치가 고려되었고 사용가치 산출을 위해서는 소득접근법과 시장접근법을 제안하였다. 이용자에 의한 가치산출을 위해, 본 연구는 조건부가치평가법을 적용하였고 이를 위해 가상 시나리오를 설정하였다.

Diallyl Sulfide와 Diallyl Disulfide에 의한 랫드의 간암발생 억제효과에 관한 연구 (Study on the Inhibitory Effects of Diallyl Sulfide and/or Diallyl Disulfide in the Rat Hepntocarcinogenesis)

  • 김배환;이영순
    • Biomolecules & Therapeutics
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    • 제3권4호
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    • pp.279-287
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    • 1995
  • This study examined the anti-cancer effects of diallyl sulfide(DAS) and/or diallyl disulfide(DDS), major components of garlic oil, with the DEN-PH model in rats, by the numbers and areas per cm$^2$ of induced glutathion S-transferase placental form(GST-P) positive foci and silver-stained nucleolar organizer regions(Ag-NORs) counts per nuclei in liver as indicator. Sprague-Dawley(SD) rats were given the diethylnitrosamine(DEN, 200 mg/kg, i.p.) as initiator and 2 weeks later, in experiment 1, rats were treated with DAS(200 mg/kg, i.g.) and/or DDS(50 mg/kg, i.g.) for 6 weeks, respectively and concomitantly and also were given the same dose of DAS and/or DDS prior to DEN treatment for 2 weeks, and in experiment II, rats were treated with potential cancer promoter, 2-acetylaminofluorene (2-AAF, 20 mg/kg, i.g.). The DAS and/or DDS were treated prior to 2-AAF for 8 weeks, respectively and concomitantly. Then the anti-promoting effects of DAS and/or DDS were assessed. All rats were subjected to the two-thirds partial hepatectomy(PH) at week 3 and sacrificed at week 8. In experiment I, DAS and/or DDS treatment only prior to DEN showed inhibition of the development of GST-P positive foci. In experiment II, DAS and/or DDS treatment prior to 2-AAF promotion showed obvious inhibition of the development of GST-P positive foci in numbers and areas and AgNORs counts. In conclusion, We found DAS and/or DDS had the preventive effects on the hepatocarcinogenesis in rats and the concomitant treatment had some additive effects compared with the each treatment and AgNORs counts correlated well with the preneoplastic hepatic lesion.

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메틸클로로실란류의 열분해를 이용한 탄화규소의 화학증착 (Chemical Vapor Deposition of Silicon Carbide by the Pyrolysis of Methylchlorosilanes)

  • 최병진;박동원;조미자;김대룡
    • 한국세라믹학회지
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    • 제32권4호
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    • pp.489-497
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    • 1995
  • The DDS((CH3)2SiCl2)+H2 gas mixture, where C atoms exist in excess in the molecules, was used for chemical vapor deposition of SiC in order to prevent codeposition of free Si in MTS(Ch3SiCl3)+H2 system. The deposition rate was more rapid than MTS, however differ from that of MTS, it decreased after shwoing a maximum at 140$0^{\circ}C$. The stoichiometry was highly improved by using the DDS as a precursor, although there exist a little pyrolytic C at 150$0^{\circ}C$. The preferred orientation was (220) in MTS, however, it changed to (111) in DDS. The microstructure of the layer deposited at lower temperature were dense, however it grew coarse with the increase in the temperature.

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항공 계기착륙 디지털 송수신 모듈 설계 (Design of Digital Transmitter and Receiver Modules in ILS)

  • 최종호
    • 한국정보전자통신기술학회논문지
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    • 제4권4호
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    • pp.264-271
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    • 2011
  • 항공기의 계기착륙을 유도하는 시스템인 ILS(Instrument Landing System)는 1947년 ICAO(International Civil Aviation Organization)에서 국제표준으로 채택되어 현재는 상용시스템으로 출시되고 있다. 본 논문에서는 통합형 ILS 디지털 송수신 모듈의 설계방법을 제안하였다. 새롭게 제안한 것은 FPGA를 이용한 디지털 이중 AM 변복조기, 샘플링 클럭 생성을 위한 DDS(Direct Digital Synthesizer), DDC(Digital Down converter) 구조의 복조기, DSP 칩을 이용한 AM 스펙트럼 분석기의 디지털 설계 기법이다. 제안한 설계 방법의 유용성을 모듈 개발 및 실험을 통해 확인한 결과, 성능이 우수한 상용 시스템으로의 활용이 가능함을 확인하였다.