• Title/Summary/Keyword: Relative stability

Search Result 922, Processing Time 0.027 seconds

Multi-output VC-TCXO having CMOS inverter for WCDMA(UMTS) (CMOS 인버터를 갖는 WCDMA(UMTS)용 다중출력 VC-TCXO)

  • Jeong Chan-Yong;Lee Hai-Young
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.43 no.8 s.350
    • /
    • pp.6-12
    • /
    • 2006
  • Recently, according to the rapid development of mobile system, the development of relative mobile components has been required, and especially, with the miniaturization of mobile component, the complex with nearby components has been progressed. In this paper, multi-output VC-TCXO (Voltage Controlled-Temperature Compensated Crystal Oscillator) for WCDMA integrates the additional CMOS inverter, so it can be the normal clipped sinewave output and additional CMOS output, and also it can be satisfied the VC-TCXO's requirements for WCDMA system. And the important characteristics of reference oscillator, like phase noise and frequency short term stability, are satisfied with WCDMA(UMTS) system's requirement In this paper, however, 25MHz is used for reference frequency, similarly and practically, we think that it can be used from 10MHz to 40MHz.

Behavior of Geotextile Tube for Erosion Control (침식방지를 위한 토목섬유튜브의 거동 분석)

  • Chang, Yong-Chai;Son, Ka-Young;Lee, Seung-Eun;Kim, Sang-Jin;Kim, Suk-Woo
    • Journal of the Korean Geotechnical Society
    • /
    • v.28 no.5
    • /
    • pp.5-12
    • /
    • 2012
  • Geotextile tube method is the latest application process to construct a variety of civil structures such as river and coastal structures by using geotextile which is a high polymer synthetic fiber. In this paper, laboratory tests and field tests were conducted in order to identify the behavior, stability and application possibility of geotextile tube which prevents the erosion of coastal sand. As a result of large-scale direct shear test, which is one of laboratory tests, the increase in friction angle was shown as the relative density increased, and friction angle of sand/geotextile was larger than that of sand/sand. As a result of field test, the behavior and stability during construction and after construction were identified through measurement, and the effect of preventing erosion was confirmed.

Non-Enzymatic Browning Reactions in Dried Alaska Pollak Stored at Different Water Activities (마른명태 저장중(貯藏中)의 수분활성(水分活性)과 갈변반응(褐變反應))

  • Kim, Mu-Nam;Choi, Ho-Yeon;Lee, Kang-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.2 no.1
    • /
    • pp.41-47
    • /
    • 1973
  • In the present work, the quality stability of sun-dried Alaska pollack, Theragra chalcogramma, was discussed in the aspects of non-enzymatic discoloration as a function of relative humidity during storage at room temperature$(20^{\circ}C)$. Frozen Alaska pollack was dressed, filleted, dried for 48 hours in the open air, and finally stored in cylindrical acrylic chambers which contained saturated specific salt solutions proposed by Rockland(1960) for humidity control. The color development of the product was analyzed by spectrophotometry at 10 day-intervals during the storage. Lipid oxidation was measured as TBA value at wavelength of 538nm. And browning pigments were extracted, divided into two fractions and measured at 460nm: one was chloroform-methanol (2:1 v/v)soluble fraction attributed to lipid oxidation, and the other was water dialyzed fraction caused by so called Maillard reaction. The TBA value showed a maximum on 30 day storage, hereafter, intended to decrease gradually. On the other hand, the rate of brown pigment development in water dialyzed fractions as well as in chloroform-methanol soluble fractions was lower at 34 to 45%RH than at any other case, and propagation of lipid oxidation was also diminished at the same levels of humidity. From the facts described previously, it is recognized that storage at 34 to 45%RH provides higher quality stability for sun-dried Alaska pollack.

  • PDF

Influence of Weak Ground Ahead of the Tunnel Face on 3D-displacement and Face Extrusion (막장전방의 연약층이 터널 3차원변위 및 막장 수평변위에 미치는 영향)

  • Jeon, Je-Sung
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.6
    • /
    • pp.189-206
    • /
    • 2003
  • During tunnel excavation in urban area a systematic monitoring is important for the purpose of determination of support type and quantity, as well as for the control of stability of both surface structures and the tunnel itself due to the frequently, and in many cases, abruptly changing ground condition. In Austria absolute displacement monitoring methods have replaced relative displacement measurements by geodetic methods to a large extent. Prompt detection of weak ground ahead of the tunnel face as well as better adjustment of excavation and support to the geotechnical conditions is possible with the help of the improved methods of data evaluation on sites. Deformation response of the ground to excavation starts ahead of the tunnel face, therefore, the deformation and state of the tunnel advance core is the key factor of the whole deformation process after excavation. In other words, the rigidity and state of the advance core play a determining role in the stability of both surface structures and the tunnel itself. This paper presents the results from detailed three-dimensional numerical studies, exploring vertical displacements, vector orientations and extrusions on tunnel face during the progressive advancement for the shallow tunnel in various geotechnical conditions.

Optimum Design of Journal Bearings considering the Wear Rate (마멸율에 관한 저널베어링의 최적설계)

  • 임오강;이왕진
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.15 no.1
    • /
    • pp.155-164
    • /
    • 2002
  • The journal bearings use in machine parts which move relative to each other and those reduce friction and wear of journals. The journal bearings are designed to operate in the hydyodynamic lubrication regime, but elastohydrodynamic lubrication nay occur if the pressures are too high or the running speeds are too low at machine elements. It is the phenomenon that the lubricant film is broken and some parts of surfaces are in rolling contact, so that wear will increase in mixed lubrication regime. The purpose of this study is to minimize the wear rate of journal bearings for extending machine life. The wear mate in mixed lubricated regime is selected as objective function because most of wear of the journal bearings develops in elastohydrodynamic lubrication. The journal bearings we represented by a bearing radius, shaft radius, and bearing width, but the bearing radius only is selected as design variables due to a bearing radius has an influence on friction loss, stability limit velocity, and film parameter, which are used as constraints. For numerical calculation, PLBA, that is a class of the RQP algorithm, is used.

Effects of Pumpkin (Cucurbita moschata Duch.) Leaf Ethanolic Extracts on Lipid Oxidation and Microbial Activity in Refrigerated Raw Ground Pork

  • Choe, Ju-Hui;Kim, Hack-Youn;Choi, Yun-Sang;Han, Doo-Jeong;Choi, Ji-Hun;Kim, Yong-Jae;Kim, Cheon-Jei
    • Food Science of Animal Resources
    • /
    • v.31 no.6
    • /
    • pp.865-871
    • /
    • 2011
  • This study was conducted to evaluate the antioxidant effects of pumpkin leaf extracted using a 50% ethanol on ground pork during storage. The pumpkin leaf extracts were added at concentrations of 0.05 (PE-0.05), 0.1 (PE-0.1), and 0.2% (PE-0.2) to ground pork, and 0.05% of ascorbic acid (As-0.05) was added as a control. Each sample was collected after 1, 4, 7, and 10 d of storage and the pH, total viable counts (TVC), conjugated dienes (CD), free fatty acids (FFA), and thiobarbituric reaction substance (TBARS) values were measured. The pH of the pork samples decreased until day 7, and then increased thereafter, except for the control and PE-0.05 sample. Lower CIE $a^*$ values were observed for pork samples containing PE relative to As-0.05 at increasing storage time (p<0.05). The addition of PE decreased the TVC, CD, FFA and TBARS values levels in the ground pork when compared to the control during 10 d of storage. These results indicate that PE can produce notable effects on meat products, such as inhibiting lipid oxidation and discoloration.

Analysis of Judgements on the validity of selective/unilateral Arbitration Agreement - In case of the Supreme Court's Judgements - (선택적 중재합의의 유효성에 대한 판례분석 - 대법원 판례를 중심으로 -)

  • Chung, Young-Hwan
    • Journal of Arbitration Studies
    • /
    • v.19 no.3
    • /
    • pp.3-24
    • /
    • 2009
  • This article discusses the validity of selective/unilateral arbitration agreement that provides arbitration as one of several dispute resolution methods. The Supreme Court has held selective/unilateral arbitration agreement that is conditional invalidity since the judgement of 2003Da318 decided on Aug. 22, 2003: In the following judgements of 2004Da42166 decided on Nov. 11, 2004 and 2005Da12452 decided on May 27, 2005, the Court stated that the selective/unilateral arbitration agreement that stipulates to resolve a dispute through arbitration or mediation would be valid as an effective arbitration agreement only if a party elects and proceeds an arbitration proceeding and another party responses to the arbitration proceeding without any objection. The definition of arbitration agreement, the formation of selective/unilateral arbitration agreement, the summary of relative judgements and academic theories will be reviewed in order to examine the appropriateness of the series of judgements of the Supreme Court. Based on such reviews, this article will investigate the adequacy of the Supreme Court judgements from the perspectives of i) the principle of party autonomy, ii) the structure of dispute resolution methods, iii) legal provisions of Arbitration Act, iv) legal stability, and v) the policy to revitalize the use of arbitration. At conclusion, this article will suggest the change of precedents of the Supreme Court's judgements with regard to the selective arbitral agreement.

  • PDF

Effect of Rainfall-Induced Infiltration on Unsaturated Weathered Soils with Varying Clay Contents (강우시 점토함유량에 따른 화강풍화토의 불포화 침투 특성)

  • 유남동;정상섬;김재홍;박성완
    • Journal of the Korean Geotechnical Society
    • /
    • v.20 no.8
    • /
    • pp.159-166
    • /
    • 2004
  • In this study, experiments on the SWCC were performed in order to find out the characteristics of unsaturated soil and to analyze the stability of unsaturated weathered slopes with rainfall-induced wetting. Several soil types classified by mixture portion of clay (CH) in the weathered soil (SW) were used in experimental tests. To achieve the SWCC, the filter paper method was used on SW with varying clay contents. A tensiometer test was used for measuring wetting front suction of the soils in a laboratory with varying relative densities. Based on the experimental results, it is shown that the wetting front suction increases as clay contest of mixture soil increases : in particular, the wetting front suction increases sharply as the clay contents increase. It is also found that wetting front suction affects the initial wetting band depth and stability of the slope.

Selection of Reliable Reference Genes for Real-time qRT-PCR Analysis of Zi Geese (Anser anser domestica) Gene Expression

  • Ji, Hong;Wang, Jianfa;Liu, Juxiong;Guo, Jingru;Wang, Zhongwei;Zhang, Xu;Guo, Li;Yang, Huanmin
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.26 no.3
    • /
    • pp.423-432
    • /
    • 2013
  • Zi geese (Anser anser domestica) belong to the white geese and are excellent layers with a superior feed-to-egg conversion ratio. Quantitative gene expression analysis, such as Real-time qRT-PCR, will provide a good understanding of ovarian function during egg-laying and consequently improve egg production. However, we still don't know what reference genes in geese, which show stable expression, should be used for such quantitative analysis. In order to reveal such reference genes, the stability of seven genes were tested in five tissues of Zi geese. Methodology/Principal Findings: The relative transcription levels of genes encoding hypoxanthine guanine phosphoribosyl transferase 1 (HPRT1), ${\beta}$-actin (ACTB), ${\beta}$-tubulin (TUB), glyceraldehyde-3-phosphate-dehydrogenase (GADPH), succinate dehydrogenase flavoprotein (SDH), 28S rRNA (28S) and 18S rRNA (18S) have been quantified in heart, liver, kidney, muscle and ovary in Zi geese respectively at different developmental stages (1 d, 2, 4, 6 and 8 months). The expression stability of these genes was analyzed using geNorm, NormFinder and BestKeeper software. Conclusions: The expression of 28S in heart, GAPDH in liver and ovary, ACTB in kidney and HPRT1 in muscle are the most stable genes as identified by the three different analysis methods. Thus, these genes are recommended for use as candidate reference genes to compare mRNA transcription in various developmental stages of geese.

Humidity-Sensitive Characteristics and Reliabilities of Polymeric Humidity Sensors Using 2-Methacryloxyethyl dimethyl 2-hydroxyethyl ammonium brornide (2-Methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide를 이용한 고분자 습도센서의 감습 특성 및 신뢰성)

  • Lee, Chil-Won;Gong, Myoung-Seon
    • Applied Chemistry for Engineering
    • /
    • v.10 no.3
    • /
    • pp.461-466
    • /
    • 1999
  • The humidity sensor containing ammonium salt was prepared from the copolymer of 2-methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide (MDHAB)/MMA/DAEMA = 6/3/1. The humid membrane was fabricated on the gold/alumina electrode by dipping. The impedances were $298k{\Omega},\;11k{\Omega}$, and $2.3k{\Omega}$ at 40%RH, 70%RH and 90%RH, respectively, at $5^{\circ}C$ and the humidity-sensitive characteristics were suitable for low temperature humidity sensor. The temperature-dependent coefficient between $5^{\circ}C$ and $20^{\circ}C$ was found to be $-0.80%RH/^{\circ}C$ and the hysteresis falled in the ${\pm}2%RH$ range. The response time was found to be 38 sec for the relative humidity ranging from 34%RH to 88%RH at $20^{\circ}C$. The reliabilities such as temperature cycle, humidity cycle, high temperature and humidity resistance, electrical load stability, stability of long-term storage and water durability were measured and evaluated for the application as a humidity sensor.

  • PDF