• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.4
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• pp.25-36
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• 1984

This paper checked up the safety criteria of the steel structural members by LRFD. And it calculated the resistance and load modulus for it by the proposed method, considering our circumstance, by establisting the taget relability index (${\beta}_0$), and compared their calculated modulus with the nominal safety factors of the road-bridge code and analyzed them. Uncertain quantity measurements fnr the resistance of the steel structural members and for the load effect are due to the method of the uncertain quantity analysis of the load and the resistance, of Galambos-Ravindra and SGST. The summary of the results is as follows: 1) Considering our circumstance, taget relibility index(${\beta}_0$) for current steel structural members are appropriate ${\beta}_0=3.5$. 2) Nominal resistance ${\Phi}^{\prime}$ of the strength design formula for 1) and nominal load modulus ${\gamma}_i^{\prime}$ are as follows; a) Both-sides support plate: ${\Phi}{^{\prime}}=0.75$, ${\gamma}_0{^{\prime}}=1.04$, ${\gamma}_L{^{\prime}}=2.08$ b) One-side support plate: ${\Phi}{^{\prime}}=0.82$, ${\gamma}_0{^{\prime}}=1.04$, ${\gamma}_L{^{\prime}}=2.11$.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.50-56
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• 2004

Dibutyl phthalate (DBP) is used extensively in the plastic industry and has been known as an endocrine disruptor. Present study was undertaken to examine whether DBP can induce oxidative stress in mice. In this study, oxidative stress was measured in terms of the modification of lipid peroxidation and gamma-glutamyl transferase (GGT) activity. The serum toxicity index, level of lipid peroxidation and triglyceride (TG), and activity of GGT were measured in male ICR mice after a single administration of DBP (5 g/kg, po). DBP did not alter serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, glucose and cholesterol level. However, the treatment with DBP was found to significantly increase the level of lipid peroxidation in liver and lung. The TG content and activity of GGT in the liver of DBP-exposed animals was also increased. These results indicate that DBP can induce mild oxidative stress in mice. The GGT activity is considered to be increased as one of the adaptive defense mechanisms to oxidative stress induced by DBP.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.286-289
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• 2006

Temporal dual gamma drive technology employing the 120Hz refresh rate was developed to enhance the off-axis viewing quality in patterned vertical alignment mode. The color shift ${\Delta}u'v'$ from on-axis to off-axis (60 deg.) for pale orange color, (R,G,B) = (196,124,96), was below 0.01, and the power exponent of gamma curve for off-axis viewing angle (60 deg.) was about 1.8, when the gamma curve for on-axis was set with power exponent of 2.4. The off-axis image distortion index was below 0.180 in contrast to the normal case ${\sim}0.23$. To elevate the response speed of liquid crystal in the intra-frame, the voltage below threshold voltage of liquid crystals was used.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1401-1405
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• 2012

Aim: To investigate the protective effect of purified fraction 1 polysaccharide extracted from Rheum tanguticum RTP1 on irradiation-induced immune damage in mice. Methods: Kunming mice were randomly divided into five groups: normal group (NC), irradiation control group (IC), RTP1 low dose (200 mg/kg), middle dose (400 mg/kg) and high dose (800 mg/kg) groups. RTP1 was adminstered by the gastric route for 14 d, mice in the NC and IC groups being given by 0.9% sodium chloride solution in the same way. The mice in all groups except NC group were irradiated with 2.0 Gy $^{60}Co{\gamma}$-ray on the fourteenth day. Immune indives of non-specific immune function, cellular immunity and humoral immunity were assessed at the 24th hour after radiation. Results: Compared with the IC group, the spleen index, thymus index, rate of carbon clearance, phagocytic function of macrophages, lymphocyte proliferation, hemolysin value of blood serum and NK activity were increased markedly (P < 0.05 or P < 0.05). Conclusion: RTP1 has an obvious protective effects on damage in ${\gamma}$-ray radiated mice.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.349-349
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• 2017

표준강수지수(Standardized precipitation index, SPI)는 가장 널리 사용되고 있는 가뭄지수로, 우리나라 뿐만 아니라 세계기상기구(World Meteorological Organization)에서도 추천하고 있는 대표적인 기상학적 가뭄 지수라고 할 수 있다. 현재 표준강수지수는 2변수 gamma 분포를 적용하여 강수 부족 상황을 지수화하여 나타내고 있는데, 일부 연구에서는 다른 확률분포형의 적용하기도 하였다(Guttman, 1999; Lloyd-Hughes and Saunders, 2002; Stagge et al., 2015). 우리나라에서는 유원희(2000)에 의해 Pearson type 3, 2변수 gamma, generalized logistic, GEV, 3변수 log-normal 분포에 따른 SPI 산정 결과를 비교한 연구가 수행되었는데, SPI 산정에는 분포형별 차이가 뚜렷하지 않다는 결론을 얻었다. 그러나 이때 금강유역 내 지점에 국한하여 적용하였고, 분포형별 적합도 검정을 수행하지 않고 SPI 산정결과만을 비교하여 우리나라에 일반적으로 적용하기에는 어려움이 있다. 따라서 본 연구에서는 우리나라의 강우특성을 반영할 수 있도록 다양한 확률분포형을 고려하여 표준강수지수를 분석하고자 한다. 이를 위해 관측기간이 30년 이상인 기상관측소의 월단위 강우자료를 구축하고, 월단위 강우자료에 다양한 확률분포형을 적용하고자 한다. 이때 적용하는 확률분포형은 2변수 gamma, Gumbel, normal 분포이다. 적정 확률분포형 선정을 위해 적합도 검정을 수행하고자 한다. 또한 각 분포형별로 산정된 표준강수지수를 기존 표준강수지수와 비교검토하고자 한다.

• Progress in Medical Physics
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• v.31 no.4
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• pp.153-162
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• 2020

Purpose: We aim to evaluate the accuracy and effectiveness of an automatically converted radiation therapy plan between Radixact machines by comparing the original plan with the transferred plan. Methods: The study involved a total of 20 patients for each randomly selected treatment site who received radiation treatment with Radixact. We set up the cheese phantom (Gammex RMI, Middleton, WI, USA) with an Exradin A1SL ion chamber (Standard Imaging, Madison, WI, USA) and GAFCHROMIC EBT3 film (International Specialty Products, Wayne, NJ, USA) inserted. We used three methods to evaluate an automatically converted radiation therapy plan using the features of the Plan transfer. First, we evaluated and compared Planning target volume (PTV) coverage (homogeneity index, HI; conformity index, CI) and organs at risk (OAR) dose statistics. Second, we compared the absolute dose using an ion chamber. Lastly, we analyzed gamma passing rates using film. Results: Our results showed that the difference in PTV coverage was 1.72% in HI and 0.17% in CI, and majority of the difference in OAR was within 1% across all sites. The difference (%) in absolute dose values was averaging 0.74%. In addition, the gamma passing rate was 99.64% for 3%/3 mm and 97.08% for 2%/2 mm. Conclusions: The Plan transfer function can be reliably used in appropriate situations.

• Journal of Preventive Medicine and Public Health
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• v.35 no.2
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• pp.169-174
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• 2002

Objective : To investigate gamma-Glutamyltransferase (${\gamma}-GTP$) and its related factors in male industrial workers. Method : Five hundred and tony male workers without heart disease, diabetes mellitus, renal disease, hepatitis, and other liver diseases were surveyed in October 1998. Blood samples were collected to test for ${\gamma}-GTP$, total-cholesterol and fasting blood glucose. A self-administered questionnaire survey on life style was also done. Results : The total geometric mean value of ${\gamma}-GTP$ was 30.6 U/L. According to a univariate analysis: age, BMI(body mass index, $kg/m^2$), alcohol consumption, current smoking, stress, diastolic blood pressure, and blood total cholesterol were significantly associated with ${\gamma}-GTP$(p<0.05). From a multiple regression analysis: BMI, alcohol consumption, current smoking, diastolic blood pressure and total-cholesterol were significantly related to ${\gamma}-GTP$(p<0.05). Coffee consumption was negatively related to ${\gamma}-GTP$, but not significantly. Conclusion : We recommend that a change in health behavior (i.e. reducing alcohol intake, controlling BMI and not smoking) is necessary to decrease ${\gamma}-GTP$ in male workers.

• Korean Journal of Environmental Agriculture
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• v.24 no.1
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• pp.66-70
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• 2005

The experiment was carried out to investigate the effects of gamma radiation on the early growth performance and physiological traits of BT2 clone tea, the most promising cultivar released by Bangladesh Tea Research Institute. The fresh shoot cuttings were irradiated with seven different levels of gamma radiation such as 0, 10, 20, 30, 40, 50 and 60 Gy from Cobalt 60Co source (Dept. of PlantBreeding, Bangladesh Institute of Nuclear Agriculture). Thereafter, the irradiated shoot cuttings were planted in polythene bags and kept under natural conditions. It was observed that callusing was initiated from 8th weeks after placement of tea shoot cuttings in the polythene bags and completed by 12th weeks. The morphological growth of tea shoot cuttings were recorded under varying levels of gamma radiation and growth stages. It was observed that the number of leaves, number of primary branches, base diameter, root length and total leaf area per plant significantly increased with the progress of time and increasing levels of gamma radiation, however, the plant height showed decreasing trend with the increasing levels of gamma radiation, which could be due to the change in chromosomal structure and genetic makeup. After 56 weeks of planting, the plant height, the number of leaves and primary branches per plant, base diameter, root length and total leaf area per plant recorded were 65.70 cm, 30.67, 7.33, 1.48 cm, 23.50 cm, and 1250.67 cm2 per plant respectively under the radiation level 60 Gy, whereas the corresponding figures of the above parameters at the control treatment were 76.21 cm, 18.33, 3.67, 0.92 cm, 17.75 cm and 778.33 cm2 per plant, respectively. A significant relationship was observed among the physiological growth parameters with the increasing levels of gamma radiation. The total dry matter gain, leaf area index, absolute growth rate and relative growth rate were significantly influenced with the rising levels of gamma radiation (up to 60 Gy), whereas the net assimilation rate of individual tea plant non-significantly responded as compared to those of control treatment. Finally after 56 weeks of planting, the maximum total dry weight gain, leaf area index, absolute growth rate, relative growth rate and net assimilation rate recorded under 60 Gay radiation level were 40.25 g/plant/week, 4.25, 1.18 g/week, 0.0621g/g/week and 17.07 g/m2/week respectively.

• Nuclear Engineering and Technology
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• v.11 no.1
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• pp.21-27
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• 1979

The relative reaction rates were measured in the TRIGA Mark II reactor core and analyzed to obtain the neutron spectrum parameters; relative neutron temperature T$^{n}$ and epithermal index (equation omitted) Measurements were made with the central thimble and the F2 position containing the light water. The relative neutron temperature was represented by the activation ratio of Lu-Mn, and the epithermal index was measured by Au-Mn foil activation. The multichannel analyzer was used to measure the relative ${\gamma}$-rays of the detector foils. The results were compared with the calculated values.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.439-445
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• 2012

The stress singularity for the excess adhesive on interface of adhesively bonded joint was investigated by using the 2-dimensional elastic boundary element method (BEM). To establish a reasonable strength evaluation method and a fracture criterion for the excess adhesive of interface in adhesively bonded joint, it is necessary to evaluate fracture parameters with various bonding conditions. Under the variations of adhesively bonded thickness (h) and diameter (d) for the excess adhesive, a stress analysis was performed, and from the results, the stress singularity index (${\lambda}$) and the stress singularity factor (${\Gamma}$) were calculated. The variations have a great influences on the stress singularity for the excess adhesive of interface in adhesively bonded joint, and the ${\Gamma}$ is reduced as the "h" and "d" increase.