• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.992-996
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• 2006

A study was carried out to examine the effect of supplementing urea-sprayed maize stover with incremental levels of Tithonia diversifolia (Tithonia) forage on dry matter (DM) intake, digestibility and live weight changes. Fifteen crossbred bucks were used in a completely randomised design for a duration of 7 weeks. The treatments comprised of a control: the basal diet (maize stover sprayed with 1% urea) plus 100 g maize germ offered alone or supplemented with: 10 (T1), 20 (T2), 30 (T3) or 40% (T4) Tithonia on a dry matter basis. All animals were allowed ad libitum access to water and mineral lick. Supplementing maize stover with Tithonia resulted in increased total DM intake (p<0.05) from 376.7 (control), to 444.1 (T1), 533.1 (T2), 519.7 (T3) and 578.9 g/day (T4) but did not significantly (p>0.05) influence the intake of stover. Diet DM digestibility increased with supplementation with T3 recording the highest value of 66.5% which was 10.6% higher than the control. Supplementation significantly increased daily weight gains (p<0.05). T4 had the highest ADG (43.7 g/day), even though there was no difference between T4 and T3 (35.7 g/day). In goats, Tithonia should be included up to 30% of ration on a DM basis for optimum production. The higher level of inclusion (40%) may be used for higher total output in terms of meat and milk but with few animals.

• Journal of Crop Science and Biotechnology
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• 제10권1호
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• pp.33-38
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• 2007

Nitrogen management at the panicle initiation stage(PI) should be fine-tuned for securing a concurrent high yield and high quality rice production. For calibration and testing of the recommendation models of N topdressing rates at PI for target grain yield and protein content of rice, three split-split-plot design experiments including five rice cultivars and various N rates were conducted at the experimental farm of Seoul National University, Korea from 2003 to 2005. Data from the first two years of experiments were used to calibrate models to predict grain yield and milled-rice protein content using shoot fresh weight(FW), chlorophyll meter value(SPAD), and the N topdressing rate(Npi) at PI by stepwise multiple regression. The calibrated models explained 85 and 87% of the variation in grain yield and protein content, respectively. The calibrated models were used to recommend Npi for the target protein content of 6.8%, with FW and SPAD measured for each plot in 2005. The recommended N rate treatment was characterized by an average protein content of 6.74%(similar to the target protein content), reduced the coefficient of variation in protein content to 2.5%(compared to 4.6% of the fixed rate treatment), and increased grain yield. In the recommended N rate treatments for the target protein content of 6.8%, grain yield was highly dependent on FW and SPAD at PI. In conclusion, the models for N topdressing rate recommendation at PI were successful under present experimental conditions. However, additional testing under more variable environmental conditions should be performed before universal application of such models.

• Environmental Analysis Health and Toxicology
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• 제30권
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• pp.4.1-4.11
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• 2015

Objectives: This survey was designed to conduct the first nationwide dietary exposure assessment on hazardous substances including the intakes of functional food and herbal medicine. In this paper, we introduced the survey design and the results of the dietary exposure status and internal exposure levels of lead (Pb), cadmium (Cd), and mercury (Hg). Methods: We selected 4867 subjects of all ages throughout Korea. We conducted a food survey, dietary survey, biomonitoring, and health survey. Results: Pb and Cd were the highest (median value) in the seaweed ($94.2{\mu}g/kg$ for Pb; $594{\mu}g/kg$ for Cd), and Hg was the highest in the fish ($46.4{\mu}g/kg$). The dietary exposure level (median value) of Pb was $0.14{\mu}g/kg$ body weight (bw)/d, $0.18{\mu}g/kg$ bw/d for Cd, and $0.07{\mu}g/kg$ bw/d for Hg. Those with a blood Pb level of less than $5.00{\mu}g/dL$ (US Centers for Disease Control and Prevention, reference value for those 1 to 5 years of age) were 99.0% of all the subjects. Those with a blood Cd level with less than $0.30{\mu}g/L$ (German Federal Environmental Agency, reference value for non-smoking children) were 24.5%. For those with a blood Hg level with less than $5.00{\mu}g/L$ (human biomonitoring I, references value for children and adults, German Federal Environmental Agency) was 81.0 % of all the subjects. Conclusions: The main dietary exposure of heavy metals occurs through food consumed in a large quantity and high frequency. The blood Hg level and dietary exposure level of Hg were both higher than those in the European Union.

• Geomechanics and Engineering
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• 제23권2호
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• pp.115-125
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• 2020

This study aims to explore practical and useful equations for rapid evaluation of uniaxial compressive strength of concrete (UCS-C) during the preliminary design stage of aggregate selection. For this purpose, aggregates which were produced from eight different intact rocks were used in the production of concretes. Laboratory experiments involved the tests for uniaxial compressive strength (UCS-R), point load index (PLI-R), P wave velocity (UPV-R), apparent porosity (n-R), unit weight (UW-R) and aggregate impact value (AIV-R) of the rock samples. UCS-C, point load index (PLI-C) and P wave velocity (UPV-C) of concrete samples were also determined. Relationships between UCS-R-rock parameters and UCS-C-concrete parameters were developed by regression analyses. In the simple regression analyses, PLI-C, UPV-C, UCS-R, PLI-R, and UPV-R were found to be statistically significant independent variables to estimate the UCS-C. However, higher coefficients of determination (R²=0.97-1.0) were obtained by multiple regression analyses. The results of simple regression analysis were also compared to the limited number of previous studies. The strength conversion factor (k) values were found to be 14.3 and 14.7 for concrete and rock samples, respectively. It is concluded that the UCS-C can roughly be estimated from derived equations only for the specified rock types.

• Journal of Korean Biological Nursing Science
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• 제12권1호
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• pp.1-7
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• 2010

Purpose: This research is to promote an walking exercise program for the subjects to continue exercise by mitigating stresses with increase in increase their physiological index. Methods: The research design was a non-equivalent control group, quasiexperimental study. The research has been executed from August 1st to September 30th 2008 by operating walking exercise program to 50 subjects. Only 24 patients who continued this program to the last were could be investigated. Results: Among the subjects who participated in the program had shown significant differences in weight and BMI. Despite of an insignificant change in skeletal muscle mass, fat mass, body fat ratio and WHR, average value for skeletal muscle mass showed an increasing tendency, while the average values for fat mass, body fat ratio and WHR showed a decreasing tendency. Conclusion: In conclusion, walking exercise program was design for the subjects to be able to exercise without an extra cost for a special tool to exercise with an positive effect on increasing health problem.

• Composites Research
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• 제13권2호
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• pp.40-50
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• 2000

종횡비가 다른 적층복합재료에 경사형 구조를 도입하고, 이것이 일방향으로의 하중을 받을 때의 좌굴특성을 최대화하기 위해서 복합재료의 각 층에서의 섬유부피분율과 두께를 변수로 sequential linear programming method를 이용하여 최적화 하였다. 이로부터 좌굴특성을 최대화 할 수 있는 최적구조를 제안하였다. 적층복합재료는 종횡비의 영향이 커서 종횡비가 1보다 작은 경우는 최외각층의 섬유부피분율을 최대화하는 방향으로 최적화가 이루어졌으나 종횡비가 2인 경우는 각층에서의 섬유부피분율과 두께비가 어느 정도 균형을 이루는 형태로 최적화가 이루어 졌다. 경사형 구조는 전통적인 균일구조의 복합재료에 비해서 섬유부피와 복합재료의 무게 절감에 큰 효과를 가지는 것으로 확인되었다.

• Journal of the Optical Society of Korea
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• 제16권1호
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• pp.63-69
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• 2012

This paper presents a method to derive the theoretical requirements for the development of a 400 mm optical window that transmits dual-band wavelengths and had a stable structure. We also present design and fabrication results. Among the required specifications, the surface figure error was defined by the transmitted wavefront deformation (TWD), ${\lambda}$/15 rms at 632.8 nm. This value was derived by estimating the predicted performances with respect to five independent items that could cause system performance degradation and then calculating the required wavefront error (WFE) to satisfy the performance goals. We measured the image resolution at each performance level to trace and verify the requirements. The article also describes a design optimization process that could minimize the weight and volume of the optical window attached to the payload securing the FOV of the camera. In addition, we accurately measured the deformation that occurred in the series of fabrication steps including processing, coating, assembly, bonding and bolting, and investigated the effects by comparing them to the results of a simulation performed in advance to derive the predicted performance.

• 한국식품영양학회지
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• 제27권2호
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• pp.318-329
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• 2014

The purpose of this study was to determine the optimal mixing ratio of Allium hookeri powder and butter in the preparation of bread. The experiment was designed according to the central composite design for estimating the response surface, which demonstrated 10 experimental points, including 2 replicates for Allium hookeri powder and butter. Further, the mechanical and sensory properties of test materials were measured. A canonical form and perturbation plot conveyed the influence of each ingredient on the final product mixture. Overall, the measurement results of the mechanical properties showed a significant increase or decrease in dough pH, sweetness, volume, weight, height, specific volume, a & b-value of crumb and, springiness (p<0.05). Moreover, the sensory measurements demonstrated a significant improvement in color, appearance, texture, moistness and, overall quality. As a result, the optimum formulation from the numerical and graphical methods was calculated as 22.65 g of Allium hookeri powder and 47.77 g butter. After optimization, DPPH free radical scavenging activity, total phenolic content, and total plate counts over 10 days were evaluated. In sum, the results revealed the antioxidant and antibiotic actions of bread with Allium hookeri powder.

• Computers and Concrete
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• 제22권5호
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• pp.493-500
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• 2018

Due to the fact that the ratio of their height to their openings is very large compared to normal beams, there are difficulties in the design and analysis of deep beams, which differ in behavior. In this study, the optimum horizontal and vertical reinforcement diameters of 5 different beams were determined by using genetic algorithms (GA) due to the openness/height ratio (L/h), loading condition and the presence of spaces in the body. In this study, the effect of different mutation operators and improved double times sensitive mutation (DTM) operator on GA's performance was investigated. In the study following random mutation (RM), boundary mutation (BM), non-uniform random mutation (NRM), Makinen, Periaux and Toivanen (MPT) mutation, power mutation (PM), polynomial mutation (PNM), and developed DTM mutation operators were applied to five deep beam problems were used to determine the minimum reinforcement diameter. The fitness values obtained using developed DTM mutation operator was higher than obtained from existing mutation operators. Moreover; obtained reinforcement weight of the deep beams using the developed DTM mutation operator lower than obtained from the existing mutation operators. As a result of the analyzes, the highest fitness value was obtained from the applied double times sensitive mutation (DTM) operator. In addition, it was found that this study, which was carried out using GAs, contributed to the solution of the problems experienced in the design of deep beams.

• 한국의류학회지
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• 제38권3호
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• pp.397-403
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• 2014

In this study, various types of Jumchi Hanji were made to develop shroud materials as a new use for Hanji. The properties of Hanji (basis weight, thickness, apparent density, bulk, tensile strength, wet tensile strength, elongation ratio, tear strength, bursting strength, and folding endurance) are measured. In all cases, Jumchi Hanji had a higher thickness, lower apparent density and higher bulk than Hanji because pores in the intervals of mulberry fiber are composed of bulk. So, it is considered to carry a value as a textile material. As for the results of the strength analysis of Jumchi Hanji, Jumchi technique enhances 25% of elongation ratio, which is regarded the most important role in textiles and 35% of bulk. Moreover, it was shown that it enhanced overall strength. In conclusion, it implies the possibility of applying it as a shroud material. Jumchi Hanji is thought to have enough potential to be developed as a material to carry the characteristics of Hanji in the textile market.