• Title/Summary/Keyword: ST17

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Thermal Analysis on a Satellite Box during Launch Stage by Analytical Solution

  • Choi, Joon-Min;Kim, Hui-Kyung;Hyun, Bum-Seok
    • International Journal of Aeronautical and Space Sciences
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    • v.4 no.2
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    • pp.17-25
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    • 2003
  • Simple methods are developed to predict temperatures of a satellite box during launch stage. The box is mounted on outer surface of satellite and directly exposed to space thermal environment for the time period from fairing jettison to separation. These simple methods are to solve a 1st order ordinary differential equation (ODE) which is simplified from the governing equation after applying several assumptions. The existence of analytical solution for the 1st order ODE is determined depending on treatment of time-dependent molecular heating term. Even for the case that the analytical solution is not available due to the time dependent term, the 1st order ODE can be solved by relatively simple numerical techniques. The temperature difference between two different approaches (analytical and numerical solutions) is relatively small (Jess than $1^{\circ}C$ along the time line) when they are applied to STSAT-I launch scenario. The present methods can be generally used as tools to quickly check whether a satellite box is safe against space environment during the launch stage for the case that the detailed thermal analysis is not available.

A Study on the Characteristic Evaluation of Sewage and Industrial Wastewater Treatment Sludges by Physico-chemical Analysis (물리화학적 분석을 통한 하 ${\cdot}$ 폐수처리 슬러지류의 특성평가)

  • Kwon, Gi-Hong
    • Journal of Environmental Health Sciences
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    • v.31 no.1
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    • pp.86-93
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    • 2005
  • Because generally large amount of sludges are generated from the process of sewage and wastewater treatment, the management and controlment of those sludge has become a important issue in many researches. In this dissertation, we conducted the research to see the physico-chemical characteristics of sludges generated from various sources. Moisture of sludges were 81.5% in textile industries, 81.4% in frame metal industries, 80.7% in 1st metal industries. Volatile solid were 22.1% in hide · rubber industries, 21.9% in coke · petroleum industries. Fixed solid were 18.5% and 17.7% in the 1st metal industries and frame metal industries. High heating value by wet base were 1,850 kcal/kg in coke · petroleum industries, 1,220 kcal/kg in hide · rubber industries, but sludges from the 1st metal industries and frame metal industries were impossible to incinerate because most of those sludges were inorganic. The leaching test showed that hazardous materials was detected in nearly every kinds of sludges. Some of sludges from hide · rubber industries and frame metal industries exceeded the leaching criteria and so they were classified as specific wastes. And other sludges generated in sewage treatment plants or other industries was below the leaching criteria.

A Study on the Jus Rerem Law and Arbitration Law of China (중국(中國)의 중재제도(仲裁制度)에 관한 관견(管見) - 중국(中國) 물권법(物權法)의 제정(制定)을 중심(中心)으로 -)

  • Kim, Yong-Kil
    • Journal of Arbitration Studies
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    • v.17 no.3
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    • pp.121-143
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    • 2007
  • The law of Jus Rerem of China enacted on March 16, 2007 came into force from October 1st, 2007. China has enacted the law of Jus Rerem. This means that all three nations of Northeast Asia have formally and substantially similar legal terms and conceptions. Therefore, they will be reciprocally influenced on the legal matters related Jus Rerem. In the year 1949 when China, as a communist country, was originally established without the private ownership system, the law of Jus Rerem was not introduced. Since the reform and the open-economy policy in the year 1978 came into force, it has become important that newly acknowledged private property has been stipulated by the law of Jus Rerem. Arbitration Law of China is enacted on August 31th, 1994 and came into force from September 1st, 1995. It is a basic law which rules Chinese arbitration system. China has enacted the law of Jus Rerem, "conformed with the 21st century", by solving a lot of issues in dispute. A socialistic idea, a traditional Chinese idea and realistic conditions of the market economy were integrated into the law of Jus Rerem. It would have a very good effect on the growth and prosperity of China.

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Sulodexide inhibits retinal neovascularization in a mouse model of oxygen-induced retinopathy

  • Jo, Hyoung;Jung, Sang Hoon;Kang, Jun;Yim, Hye Bin;Kang, Kui Dong
    • BMB Reports
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    • v.47 no.11
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    • pp.637-642
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    • 2014
  • Sulodexide is a mixed glycosaminoglycan composed of heparin and dermatan sulfate. In this study, the anti-angiogenic effect of sulodexide was investigated using an oxygen-induced retinopathy (OIR) mouse model. The retinas of sham-injected OIR mice (P17) had a distinctive central area of nonperfusion, and this area was significantly decreased in sulodexide-injected mice. The number of neovascular tufts measured by SWIFT_NV and mean neovascular lumen number were significantly decreased in sulodexide-injected mice. Hyperbaric oxygen exposure resulted in increased levels of VEGF, MMP-2 and MMP-9, and when mice were treated with sulodexide, a dose-dependent reduction in VEGF, MMP-2 and MMP-9 levels was observed. Our results clearly demonstrate the anti-angiogenic effect of sulodexide and highlight sulodexide as a candidate supplementary substance to be used for the treatment of ocular pathologies that involve neovascularization.

Relationships between Muscle α-Tocopherol Concentrations and Metmyoglobin Percentages during Display of Six Muscles of Japanese Black Steers

  • Muramoto, T.;Shibata, M.;Nakanishi, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.7
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    • pp.1014-1018
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    • 2004
  • Relationships between muscle $\alpha$-tocopherol oncentrations and metmyoglobin percentages during display of six muscles, m. serratus ventralis (SV), m. psoas major (PM), m. gluteus medius (GM), m. semimembranosus (SM), m. semitendinosus (ST) and m. longissimus lumborum (LL), of Japanese Black steers slaughtered at 28 months of age were studied. Steers were supplemented with 0, 2,000 and 4,000 mg $\alpha$-tocopheryl acetate/head/day for 28 days prior to slaughter in the VE 0, the VE 2,000 and the VE 4,000 groups, respectively. $\alpha$-Tocopherol concentrations in PM, GM, SM, ST and LL of the VE 2,000 and the VE 4,000 groups were significantly (p<0.05) higher than those of the VE 0 group. There were no significant (p>0.05) differences in $\alpha$-tocopherol concentrations in all muscles between the VE 2,000 group and the VE 4,000 group. The muscle $\alpha$-tocopherol concentrations ($\ell$/g meat) which can retard metmyoglobin formation in muscles were estimated to be 5.3 for SV, 4.5 for PM, 4.2 for GM, 4.0 for SM, 3.6 for ST and 3.5 for LL. The equation to predict color-shelf-life of each muscle from the $\alpha$-tocopherol concentration in each muscle could be obtained.

Consolidation Behavior of Soft Ground by prefabricated Vertical Drains (연직드레인 공법에 의한 연약지반의 압밀거동)

  • 이달원
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.5
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    • pp.133-143
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    • 2000
  • A large scale field test of prefabricated vertical drains was performed to anayze the effect of parameters of the very soft clay at a test site. compression index and the coefficient of horizontal consolidation obtained by back-analysis of settlement data were compared with those obtained by means of laboratory tests. Hyperbolic method, Asaoka meoth and curve fitting method were used to compute final settlement of coefficient of consolidation. The relationships of settlement measurement(Sm) versus design settlement(St) and the measurement consolidation ratio(Um) versus design consolidation (Ut) were shown as Sm=(1.0~1.1) St , Um=(1.13~1.17) Ut at 1.0m spacing of drain and Sm=(0.7~0.8)St, Um= (0.92~0.99) Ut at 1.5 m spacing of drain, respectively . The relationships of the field compression index(CcField) and virgin compression index(vcc lab) were shown as Ccfield =(1.0~1.2)vcc lab . But it was nearly within the same range when considering the error factor with the determination method of virgin compression index and the prediction back-analysis of the settlement data was larger than the coefficient of vertical consolidation, and the ratio of consolidation coefficient (Ch/Cv) was Ch =(2.4~2.9) Cv , Ch=(3.4~4.2) Cv at 1.0m and 1.5m spacing of drain, respectively.

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Clinical Study of Aged Patients with Hoarseness (노인애성환자에 대한 임상적연구)

  • 안철민;권기환
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.7 no.1
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    • pp.27-31
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    • 1996
  • The voice of aged persons is known generally to be somewhat different from that of other adults, suggesting that laryngeal change occurs with advancing age. However, because knowledge of the voice characteristics of aged persons is limited, it is difficult to judge whether their voices arc normal. Chart review and laryngoscopic examination from ninety-one patients with hoarseness over the age of 60(1st group) and one hundred sixteen patients with hoarseness below the age of 50(2nd group) were done to define aging related voice disorders. The following results were obtained. 1) Associated diseases related to laryngeal disease were hypertension(12%), pulmonary disease(4.4%), thyroid disease(1.1%) in 1st group and hypertension(9.5%), thyroid disease(1.7%) in 2nd group. 2) The underlying diseases causing hoarseness in order of frequency were benign vocal fold lesion(37.7%), inflammatory disease(36.8%), functional dysphonia(17%) in 1st group and benign vocal fold lesion(43.6%), functional dysphonia(26.3%), inflammatory disease(16.5%) in 2nd group. 3) In stroboscopic findings, atrophy and sulcus of vocal cords are more prevalent in males than in females and edema of vocal cords is more common in females. Generally the voice characteristics of aged persons depend on the mass of the vocal folds which may be decreased through atrophy or be increased by edema. However, other factors such as systemic diseases, drug side effects and compensatory mechanism to presbylaryngis must be taken into account in diagnosing and treating voice disorders in aged persons.

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Effect of Co-initiator on the Size Distribution of the Stable Poly(Styrene-co-Divinylbenzene) Microspheres in Acetone/Water Mixture

  • Choi, Jin-Young;Lee, Kang-Seok;Lee, Byung-Hyung;Choe, Soon-Ja
    • Macromolecular Research
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    • v.17 no.7
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    • pp.483-490
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    • 2009
  • Stable poly(styrene-co-divinylbenzene) [P(St-co-DVB)] micro spheres with narrow size distribution were synthesized in the presence of 2,2'-azobis(2,4-dimethyl valeronitrile) (V-65) and co-initiator in an acetone/water mixture in the precipitation polymerization at $53^{\circ}C$ for 24 h. Potassium peroxodisulfate (KPS), ammonium peroxodisulfate (APS) and sodium peroxodisulfate (NaPS) were used as co-initiators. The optimum ratio of acetone to water for the formation of a narrow distribution of P(St-co-DVB) particles was 49:11 (g/g). The optimum co-initiator compositions for narrow distribution were 9:1 (g/g) for V-65 to KPS, 11:1 for V-65 to APS and 6:1 for V-65 to NaPS. The yield for these compositions was $54{\sim}57%$ and the largest particle size was obtained with the lowest zeta-potential and CV values. From the XPS measurements, the charge density was increased but the zeta potential decreased with increasing sulfur content, implying that the sulfate group provides the electrostatic stabilization on the particle surface. This suggested that the self-crosslinking between styrene and DVB, the electrostatic stabilization of initiators, and the balanced hydrophobic and hydrophilic properties of the solvents are responsible for the formation of stable P(St-co-DVB) spherical particles with narrow size distribution.

Clinicopathological Diagnosis of Gentamicin and Ethylene glycol Induced Acute Renal Failure in Dogs (개에서 Gentamicin과 Ethylene glycol에 임상병리학적 진단)

  • 김지현;이영재;이경갑
    • Journal of Veterinary Clinics
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    • v.17 no.2
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    • pp.327-333
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    • 2000
  • The diagnostic method was, evaluated in experimentally induced acute renal failure in doges. Ten male dogs weighing from 5 to 10 kg were assigned to two groups(gentamicin & ethylene glycol treated group) al random. Gentamicin sulfate at 10 mg/kg of body weight, t.i.d., for 7 days and ethylene glycol at 3 ml/kg of body weight once used in a randomized complete block design with tee treatments in block. The samples(blood, urine) were collected before and 1,3,5,7,9 and l1th day after administration. The serum creatinine concentration and BUN(blood urea nitrogen) were sig- nificantly increased at the 7th day than before administration in gentamicin treated group (p<0.05), bolt there was significant increase at the 1st day than before administration in ethylene glycol treated group(p<0.05). The urine GGT(gramma glutamyl transpeptidase) and GGT/creatinine were significantly increased at the 1st (lay after administration in gentamicin treated group (p<0.05). But in ethylene glycol treated group, there was no significant changes. The value of FENa (fractional excretion of sodium) was significantly increased at the 3rd day after administration in gentamicin treated group and the 1 st day after administration in ethylene glycol treated group (p<0.05). These results suggest that FENa was a good parameter of renal function in dogs with acute renal failure.

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Cervical Contrast-Enhanced MRA Using Whole Body Coil at 3.0T: Initial Clinical Experience

  • Kwon, Jung-Hwa;Son, Chul-Ho;Kim, Hong;Woo, Sung-Gu;Seo, Soo-Ji
    • Proceedings of the KSMRM Conference
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    • 2002.11a
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    • pp.89-89
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    • 2002
  • Purpose: To report initial experience and evaluate feasibility of cervical carotid artery contrast-enhanced MR angiography (CEMRA) using whole body coil at 3.0T Method: Twenty-eight patients (14 male, ages 41-80, mean age 63) underwent CEMRA at the 3.0T using whole body coil and 3D-FSPGR (TR/TE 6.6/l.3 msec, FA 30, thickness 1.3mm), and thirty patients (17 male, ages 30-80, mean age 57) underwent CEMRA at the 1.5T using Helmholtz neck coil and 3D FLASH sequence (TR/TE 3.8/l.4msec, FA 35, thickness 1mm). At both 1.5 and 3.0T, a power injector (Spectris) injected 20m1 of gadolinium to the right or left antecubital vein at a rate of 3mL/s. All CEMRA cases were accepted by one neuroradiologiest. We measured the signal intensities at the bifurcation of common carotid artery (CCA), vertebral artery (V2) and two surrounding tissues (ST) and noise at the background in all patients, and also compared contras-to-noise ratios (CNR) of CCA/ST and V2/ST at 3.0 and 1.5T

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