• 제목/요약/키워드: Relative Stability

검색결과 918건 처리시간 0.025초

AOM 시험에 의한 팜유와 우지에 대한 몇가지 산화방지제 효과와 비교 (Relative Effectiveness of Some Antioxidants on Palm Oil and Beef Tallow by AOM Tests)

  • 양주홍;장영상;신효선
    • 한국식품과학회지
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    • 제20권4호
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    • pp.563-568
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    • 1988
  • 몇가지 산화방지제와 상승제를 첨가하여 가열한 팜유와 우지에 대한 산화방지 효과를 AOM시험에 의하여 비교 연구하였다. 팜유에 0.02% TBHQ를 첨가하였을때 같은 농도의 다른 산화방지제를 첨가하였을 때 보다 AOM 안정성이 가장 우수하였다. 우지에 0.02% TBHQ를 첨가하였을 때는 같은 농도의 BHA와 BHT 혼합제와 $DL-{\alpha}-T$을 첨가한 것 보다 AOM 안정성이 증가하였으나 같은 농도의 ${\delta}-T$와 MT을 첨가한것 보다 증가하지 않았다. 팜유와우지에 $DL-{\alpha}-T$을첨가하였을 때는 BHA와 BHT 혼합제를 첨가한 것 보다 AOM안정성이 증가하지 않았다. 그러나 팜유와 우지에 ${\delta}-T$와 MT를 첨가하였을 때는 $DL-{\alpha}-T$를 첨가하였을때 보다 AOM 안정성이 증가되었고 ${\delta}-T$와 MT 간에는 큰 차이가 없었다. $DL-{\alpha}-T$${\delta}-T$에 대한 구연산의 상승효과는 팜유보다 우지에서, $DL-{\alpha}-T$에 대한 AP의 상승효과는 우지보다 팜유에서, ${\delta}-T$에 대한 AP의 상승효과는 팜유보다 우지에서 각각 더 효과적이었다. 가열중 tocopherol류의 손실량은 우지보다 팜유에서 더 적었다.

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감자의 품질안정성에 대한 저장 온.습도의 영향 (Effect of Storage Temperature and Humidity on the Quality Stability of Potatoes)

  • 권중호;변명우
    • 한국식품저장유통학회지
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    • 제2권2호
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    • pp.243-249
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    • 1995
  • Potatoes, Irish cobbler, were subject to quality evaluation from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 11 months. Quality criteria were sprouting, rotting, weight changes, moisture, total sugar, reducing sugar and vitamin C. Low temperature condition(LT, 2∼4$^{\circ}C$, 80% RH) was enough to preserve Potatoes for 11 months, but it was indicated to be limitations that the increase in reducig sugar as well as sprouting by about 3.3 to 6.7% occurred from the 3rd month of storage. Meanwhile, pit temperature(PT, 3∼15$^{\circ}C$, 75∼85% RH), room temperature(RT, 7∼17$^{\circ}C$, 80∼95% RH) and ambient temperature(AT, 2∼25$^{\circ}C$, 62∼72 RH) were shown infeasible conditions for the storage of potatoes mainly due to the increase In sprouting-rate and subsequent quality-loss after 3 months of storage. Based on the results, it proposed that more economical conditions, ranging 10 to 15$^{\circ}C$ and about 80% RH following sprout inhibition treatment should be used for the long-term storage of potatoes.

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층상형 혼합광물의 상호작용계수의 계산 및 응용 (Calculation of Interaction Parameters in Mixed Layer Minerals and their Application)

  • 이성근;김수진
    • 한국광물학회지
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    • 제10권2호
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    • pp.97-104
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    • 1997
  • Based on the method of determination for relative stability of each phase from the difference among the interaction parameters of the phases consisting the mixed layer, the types of interactions between layers were specified and interaction parameter between layers in ordered domain was analytically derived as a function parameter between layers in ordered domain was analytically derived as a function of not only temperature and mole fraction of layers but also ordering parameter. Interaction parameter between the different layers in ordered phase, L is as follows:{{{{ {L }_{1 } (X,Q,T)= { C} over { Q} -4(1-2Q) { L}^{2 } - { RT} over {2} ln { 1} over {2 } - { 2RT} over { { X}_{ s} } ln { { 4QX}`_{s } ^{2 } } over {(1- { X}_{s }- { QX}_{s })( { X}_{s }- {QX }_{s } ) } }}}}L2 is the interaction parameter between ordered and disordered phase in domain and is the mole fraction of the domain which represent the infinite length of mixed layer mineral and Q and C are the reaction progress parameter and arbitrary constant, respectively. This equation was used for the I/S mixed layer clay minerals to infer the relative stability of R1 type I/S mixed layer in the temperature range from 373K to 450K. The result of calculation suggest that, owing to the decrease in interaction parameter with increasing temperature. The interaction parameter decreases more rapidly with decreasing mole fraction of smectite in domain, which is consistent with the fact that the probability of finding the series smectite layer is lo in the domain with small mole fraction of smectite layers in natural system.

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GIS를 이용한 한국 동남부지역의 상대적 사면안정성 분류도 작성 (Relative Slope - stability Mapping in the Southeastern Part of Korea Using GIS)

  • 한대석;이사로;김경수;최영섭;유일현
    • Spatial Information Research
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    • 제6권1호
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    • pp.25-33
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    • 1998
  • 연구대상 지역은 1:50,000지형도 12매(김해, 부산, 밀양, 양산, 방어진, 동곡, 언양, 울산, 영천, 경주, 불국사 및 감포)를 포함하는 지역으로서 총 면적은 약 5,900Km/sup 2/에 이른다. 본 연구서는 4개의 주제도, 즉 산사태 및 불안정사면 분포도, 경사분류도, 토양분류도 및 선구조밀도도의 작성을 다루고 있다. 작성한 4개의 주제도와 GIS를 이용하여 연구지역의 상대적 사면안정성 분류도(축척 1:100,000)를 작성하였는데, 본 도는 광역 토지이용계획에 활용될 수 있다.

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깨다식의 포장재에 따른 저장성 조사 (The Study on Storage Stability according to Packaging Material of Traditional Sesame Dasik)

  • 김진숙;한영실
    • 한국지역사회생활과학회지
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    • 제15권2호
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    • pp.179-187
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    • 2004
  • The purpose of this study is to investigate the preservation of traditional sesame dasik when stored in different packaging material by comparing its physical and sensorial characteristics. The quality and sensory characteristics of sesame dasik that were evaluated were moisture content, water activity, number of microflora, texture profile, Hunter color different value, and sensory properties (color, chewiness, overall acceptability, etc) during the storage at 35\pm1^\circ{C}$ temperature and $73\pm{2%}$ relative humidity. And the packaging materials were paper boxes (coated 0.02mm thickness polyethylene film), plastic boxes, and oriented polypropylene laminated film. Traditional sesame dasik is made from sesame powder 100g, honey 25g, rice syrup 25g, and table salt 0.5g. During the storage period, the changes in water content and water activity of sesame dasik with different packaging material showed a slight decline. On the other hand, it increased in hardness, and "a" and "b" value of Hunter color difference during the storage. Texture profile analysis data change in hardness was the greatest after the third day in a paper box, and it was affected by the moisture content of dasik and the temperature and relative humidity of the air. Therefore plastic boxes or oriented polypropylene laminated film was found to be better suited than paper boxes for storing sesame dasik.

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마찰기인 접촉 강성을 가지는 2-자유도계 면외 방향 진동 시스템의 선형 안정성 해석 (Linear Stability Analysis of an Out-of-plan Motion of Vibration of a Two Degree-of-freedom with Contact Stiffness)

  • 조용구;신기홍;이현영;오재응;이수갑
    • 한국소음진동공학회논문집
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    • 제15권3호
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    • pp.259-265
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    • 2005
  • A two-degree-of-freedom out-of-plane model with contact stiffness is presented to describe dynamical interaction between the pad and disc of a disc brake system. It is assumed that the out-of-plane motion of the system depends on the friction force acting along the in-plane direction. Dynamic friction coefficient is modelled as a function of both in-plane relative velocity and out-of-plane normal force. When the friction coefficient depends only on the relative velocity, the contact stiffness has the role of negative stiffness. The results of stability analysis show that the stiffness of both pad and disc is equally important. Complex eigen value analysis is conducted for the case that the friction coefficient is also dependent on the normal force. The results further verify the importance of the stiffness. It has also been found that increasing the gradient of friction coefficient with respect to the normal force makes the system more unstable.

접촉 강성을 고려한 디스크브레이크의 면외진동 해석 (Analysis of Out-of-plane Motion of a Disc Brake System Considering Contact Stiffness)

  • Joe, Yong-Goo;Oh, Jae-Eung;Shin, Ki-Hong
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.597-600
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    • 2004
  • A two-degree-of-freedom out-of-plane model with contact stiffness is presented to describe dynamical interaction between the pad and disc of a disc brake system. It is assumed that the out-of-plane motion of the system depends on the friction force acting along the in-plane direction. Dynamic friction coefficient is modelled as a function of both in-plane relative velocity and out-of-plane normal force. When the friction coefficient depends only on the relative velocity, the contact stiffness has the role of negative stiffness. The results of stability analysis show that the stiffness of both pad and disc are equally important. Complex eigenvalue analysis is conducted for the case that the friction coefficient is also dependent on the normal force. The results further verify the importance of the stiffness. It has also been found that increasing the gradient of friction coefficient with respect to the normal force makes the system more unstable. Nonlinear analysis is also performed to demonstrate various responses. Comparing the responses with experimental data has shown that the proposed model may qualitatively well represent a certain type of brake noise.

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Y-TZP/Ce-TZP 구조세라믹스의 제조 및 특성연구 (Fabrication and Characteristics of Y-TZP/Ce-TZP Structural Ceramics)

  • 이종현;이윤복;김영우;오기동;박흥채
    • 한국세라믹학회지
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    • 제33권10호
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    • pp.1177-1185
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    • 1996
  • Y-TZP/Ce-TZP ceramics having relative sintered densities of>95% average grain sizes of 0.36$\mu\textrm{m}$ microhar-dness of 1150 kg/mm2 fracture strength of 390-830 MPa and toughness of 6.4-10.2 MPa$.$mm1/2 were prepared by conventional sintering of 3 mol% Y2O3-ZrO2 and 12 mol% CeO2-ZrO2 powders at 1400 and 1500$^{\circ}C$ The average grain sizes of Y-TZP/Ce-TZP ceramics were mainly governed by those of Ce-TZP. White increasing Ce-TZP content toughness increased while microhardness and fracture strength decreased. With comparing microhardness and toughness fracture strength was more sensitive on not only grain size but also other factors such as microstructural and compositional variations. The densification of Y-TZP/Ce-TZP cermaics was not greatly affected by composition and soaking time at temperature over 1400$^{\circ}C$ With increasing CE-TZP content the stability of t-ZrO2 decreased under thermal aging in air whereas increased in hydrothermal atmosphere and aqueous solution.

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A Connection Entropy-based Multi-Rate Routing Protocol for Mobile Ad Hoc Networks

  • Hieu, Cao Trong;Hong, Choong-Seon
    • Journal of Computing Science and Engineering
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    • 제4권3호
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    • pp.225-239
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    • 2010
  • This paper introduces a new approach to modeling relative distance among nodes under a variety of communication rates, due to node's mobility in Mobile Ad-hoc Networks (MANETs). When mobile nodes move to another location, the relative distance of communicating nodes will directly affect the data rate of transmission. The larger the distance between two communicating nodes is, the lower the rate that they can use for transferring data will be. The connection certainty of a link also changes because a node may move closer to or farther away out of the communication range of other nodes. Therefore, the stability of a route is related to connection entropy. Taking into account these issues, this paper proposes a new routing metric for MANETs. The new metric considers both link weight and route stability based on connection entropy. The problem of determining the best route is subsequently formulated as the minimization of an object function formed as a linear combination of the link weight and the connection uncertainty of that link. The simulation results show that the proposed routing metric improves end-to-end throughput and reduces the percentage of link breakages and route reparations.

골격형 안면 비대칭 부정교합자에 대한 정모두부방사선 계측학적 연구 (A POSTEROANTERIOR ROENTGENOCEPHALOMETRIC STUDY OF SKELETAL CRANIOFACIAL ASYMMETRIC PATIENTS)

  • 천옥진;서정훈
    • 대한치과교정학회지
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    • 제20권3호
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    • pp.565-581
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    • 1990
  • This study was undertaken to investigate the degree of asymmetry in each part of the head in skeletal craniofacial asymmetric patients, and secondarily to determine the nature of difference existed between asymmetric patients and normal persons. The subjects consisted of 49 asymmetric adult patients and 52 normal adults, and the average ages were 21 years 5 months and 23 years 5 months, respectively. The computerized analyses of 33 linear measurements, 12 angular measurements, and 8 surface areas from posteroanterior cephalometric radiograph were carried out. The conclusions were as follows; 1. Asymmetry was a common finding in both normal and asymmetric group. 2. When the analyses were undertaken after the head was divided into 3 parts anteroposteriorly and superoinferiorly in the asymmetric patients, there were significant asymmetries in all parts excepts in the cranial base region. 3. When the analyses were undertaken after the head was divided into respective 3 parts anteroposteriorly in the asymmetric patients, the more posterior part showed relative stability than the more anterior part. 4. When the analyses were undertaken after the head was divided into 3 parts superoinferiorly in the asymmetric patients, the more superior part showed relative stability than the more inferior part. 5. Twelve variables indicating asymmetry were selected and the highest ranked variable was Me-Mid-sagittal reference line.

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