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Design and Strength Analysis of a Mast and Mounting Part of Dummy Gun for Multi-Mission Unmanned Surface Vehicle (복합임무 무인수상정의 마스트 및 특수임무장비 장착부 설계 및 강도해석)

  • Son, Juwon;Kim, Donghee;Choi, Byungwoong;Lee, Youngjin
    • The Journal of Korean Institute of Information Technology
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    • v.16 no.11
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    • pp.51-59
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    • 2018
  • The Multi-Mission Unmanned Surface Vehicle(MMUSV), which is manufactured using glass Fiber Reinforced Plastic(FRP) material, is designed to perform a surveillance and reconnaissance on the sea. Various navigation sensors, such as RADAR, RIDAR, camera, are mounted on a mast to perform an autonomous navigation. And a dummy gun is mounted on the deck of the MMUSV for a target tracking and disposal. It is necessary to analyze a strength for structures mounted on the deck because the MMUSV performs missions under a severe sea state. In this paper, a strength analysis of the mast structure is performed on static loads and lateral external loads to verify an adequacy of the designed mast through a series of simulations. Based on the results of captive model tests, a strength analysis for a heave motion of the mast structure is conducted using a simulation tool. Also a simulation and fatigue test for a mounting part between the MMUSV and the dummy gun are performed using a specimen. The simulation and test results are represented that a structure of the mast and mounting part of the dummy gun are appropriately designed.he impact amount are performed through simulation and experiments.

Phytosterols content of Keunnunjami germ and its antioxidative effects in adult rats (큰눈자미 배아의 식물성 스테롤 함량 및 성숙기 흰쥐에서 항산화 효과)

  • Liang, Jie;Ma, Jing Wen;Chung, Soo Im;Kang, Mi Young
    • Journal of Nutrition and Health
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    • v.53 no.2
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    • pp.99-110
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    • 2020
  • Purpose: The rice germ fraction is a better source of protein, lipid, and fiber than the rice endosperm. Furthermore, the rice germ is rich in bioactive phytochemicals such as γ-aminobutyric acid, tocopherols, tocotrienols, phytic acid, and so on. In this study, the phytosterol content and antioxidant activity of Keunnunjami germ (KG) or normal rice germ supplement were investigated in healthy adult rats. Methods: In vitro, quantitative assessment of phytosterols, including β-sitosterol, campesterol, cycloartenol, and stigmasterol, was performed. Comparative antioxidant activities of 2 rice germs were measured based on DPPH radical scavenging activity, reducing power, and ABTS radical scavenging capacity. In vivo, male Spraque-Dawley rats (30-weeks-old) were randomly assigned a diet of normal control (NC, AIN-93M diet), AIN-93M diet supplemented with normal rice germ 3% (NG3), or AIN-93M diet supplemented with KG 3% (KG3) and fed for 8 weeks. Results: KG contained significantly higher campesterol and stigmasterol contents and antioxidant activity than normal rice germ. The KG3 group exhibited significantly lower body weight gain as well as inguinal and total white adipose tissue weights. There were no significant differences in plasma glucose, insulin, C-peptide, or homeostasis model assessment of insulin resistance level among the 3 groups. The plasma tumor necrosis factor-α concentration was significantly lower while leptin, advanced oxidation protein products, and interleukin-6 showed downward trends in the KG3 group. In addition, the superoxide dismutase level of the KG3 group was significantly higher compared to the NC and NG3 groups. Conclusion: This study indicates that KG can be considered as a valuable source of phytosterol components. Lastly, KG has strong antioxidant properties and may have potential to ameliorate elevation of proinflammatory cytokine production with age.

A Study on User Interface of the Broadband Access Network Operation Support System (광대역 가입자망 운용관리를 위한 그래픽 유저 인터페이스(GUI) 개발에 관한 연구)

  • 장은상;이종호;임현민;하동석
    • Archives of design research
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    • v.12 no.4
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    • pp.61-68
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    • 1999
  • Most of the time, developers spend their energy to analyze the main function of the system or make source codes. As a result, they can not consider user interface on their own system and this is true in most programmer's world. But we want to consider the design concept in developing mechanism. In this case we have to upgrade the legacy system which maintaining the transmission system using the copper cables, and add the transmission system using the optical fiber cables. Therefore we design the user interface make easy for end users who are using the maintaining system on copper cables not to confuse the new system which include optical fibers. Especially, we are consider the developing model of design policy and real user to make easy to use new system. In this paper we will describe the instance to adapt the design concept on Broadband Access Network Operation Support System.

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Geotechnical Engineering Progress with the Incheon Bridge Project

  • Cho, Sung-Min
    • Proceedings of the Korean Geotechical Society Conference
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    • pp.133-144
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    • 2009
  • Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

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FEA for RC Beams Partially Flexural Reinforced with CFRP Sheets (CFRP 시트로 부분 휨 보강된 철근콘크리트 보의 유한요소해석)

  • Kim, Kun-Soo;Park, Ki-Tae;Kim, Byeong Cheol;Kim, Jaehwan;Jung, Kyu-San
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.5
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    • pp.9-16
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    • 2020
  • A CFRP sheet has been applied as a structural reinforcement in the field, and various studies are conducted to evaluate the effect of CFRP sheets on reinforced concrete. Although many experiments were performed from previous studies, there are still limitations to analyze structural behaviors with various parameters in experiments directly. This study shows the FEA on structural behaviors of RC beams reinforced with CFRP sheets using ABAQUS software. To simulate debonding failure of CFRP sheets which is a major failure mode of RC beam with CFRP sheets, a cohesive element was applied between the bottom surface of RC beam and CFRP sheets. Both quasi-static method and 2-D symmetric FE model technique were performed to solve nonlinear problems. Results obtained from the FE models show good agreements with experimental results. It was found that reinforcement level of CFRP sheets is closely related to structural behavior of reinforced concrete including maximum strength, initial stiffness and deflection at failure. Also, as over-reinforcement of CFRP sheets could give rise to the brittle failure of RCstructure using CFRP sheets, an appropriate measure should be required when installing CFRP sheets in the structure.

Microparticulation/Air Classification of Rice Bran: Characteristics and Application (초미세분쇄/공기분급을 이용한 탈지미강 분획의 특성과 응용)

  • Park, Dong-June;Ku, Kyung-Hyung;Mok, Chul-Kyoon
    • Korean Journal of Food Science and Technology
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    • v.25 no.6
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    • pp.769-774
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    • 1993
  • Defatted rice bran was microparticulated using fluidized bed opposed jet mill and air-classified at different air classifying wheel speed (ACWS) in Turboplex classifier. The median particle size and the standard deviation decreased, and concomitantly the specific surface area increased generally with increasing ACWS. The protein, fat and ash contents of the recovered rice bran increased with ACWS. The contents of minerals; magnesium, zinc, iron and manganese; increased positively with ACWS. The phytic acid content, however, was slightly higher at middle ACWS. The dietary fiber content was highest in the ACWS 15,000 rpm fraction showing 31.47%. Higher ACWS resulted in lighter colored powder. The water holding capacity (WHC) showed the maximum value at ACWS 12,000 rpm and decreased with increasing ACWS, while the oil holding capacity (OHC) increased with ACWS. The rheological property of the microparticulated rice bran/water suspension fitted to the linear model. The yield stress and viscosity of the suspension increased with ACWS. The shape of microparticulated rice bran at ACWS 21,000 rpm was spherical, and the median particle size was $3.7{\mu}m$. When cake was prepared with substitution of microparticulated rice bran at 5%, the cake height and volume increased remarkably.

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The association of dietary patterns with insulin resistance in Korean adults: based on the 2015 Korea National Health and Nutrition Examination Survey (한국 성인의 식사 패턴과 인슐린 저항성 간의 상관성: 2015년도 국민건강영양조사를 이용하여)

  • Kim, I Seul;Yang, Yoon Jung
    • Journal of Nutrition and Health
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    • v.54 no.3
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    • pp.247-261
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    • 2021
  • Purpose: This study was conducted to identify the association between insulin resistance and the major dietary patterns of Korean adults. Methods: This study used data from the 2015 Korea National Health and Nutrition Examination Survey. The subjects were 2,276 adults aged 19 to 64 years old. Based on the food frequency questionnaire data, 112 food items were reclassified into 30 food groups. The principal component analysis method was applied to identify major dietary patterns. We used homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) value as indicators of insulin resistance. The association between major dietary patterns and insulin resistance was investigated using logistic regression analysis. Results: Three major dietary patterns were identified and assigned descriptive names based on the food items with high loadings: 'healthy Korean meal pattern', 'western meal pattern', and 'white rice, alcohol, meat pattern'. As the 'white rice, alcohol, meat pattern' score increased, significant increasing trends for fasting glucose concentration and HOMA-IR and a significant decreasing trend for QUICKI were observed after adjusting for age and sex. The odds ratio of insulin resistance according to the 'healthy Korean meal pattern' and the 'western meal pattern' were not statistically significant. the 'white rice, alcohol, meat pattern' showed a significant positive association with the risk of insulin resistance after adjusting for covariates. Conclusion: These results suggest that the 'white rice, alcohol, meat pattern' is positively associated with the risk of insulin resistance. The white rice, alcohol, meat pattern was related to the high consumption of alcohol together with rice or meat. This pattern was also associated with the high intake of sodium and low intakes of vitamin C, calcium, potassium, and dietary fiber. To confirm the association, further longitudinal studies are required.

Functional Properties of Soy Protein Isolates Prepared from Defatted Soybean Meal (탈지대두박(脫脂大豆粕)에서 추출(抽出)한 분리대두단백(分離大豆蛋白)의 식품학적(食品學的) 성질(性質))

  • Byun, Si-Myung;Kim, Chul-Jin
    • Korean Journal of Food Science and Technology
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    • v.9 no.2
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    • pp.123-130
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    • 1977
  • A laboratory study was made to develop a simple and economic model method for the systematic determination of functional properties of 'Soy Protein Isolates (SPI)' prepared from defatted soybean meal. These are required to evaluate and to predict how SPI may behave in specific systems and such proteins can be used to simulate or replace conventional proteins. Data concerning the effects of pH, salt concentration, temperature, and protein concentration on the functional properties which include solubility, heat denaturation, gel forming capacity, emulsifying capacity, and foaming capacity are presented. The results are as follows: 1) The yield of SPI from defatted soybean meal increased to 83.9 % as the soybean meal was extracted with 0.02 N NaOH. 2) The suitable viscocity of a dope solution for spinning fiber was found to be 60 Poises by using syringe needle (0.3 mm) with 15 % SPI in 0.6 % NaOH. 3) Heat caused thickening and gelation in concentration of 8 % with a temperature threshold of $70^{\circ}C$. At $8{\sim}12\;%$ protein concentration, gel was formed within $10{\sim}30\;min$ at $70{\sim}100\;^{\circ}C$. It was, however, disrupted rapidly at $125\;^{\circ}C$ of overheat treatment. The gel was firm, resilient and self-supporting at protein concentration of 14 % and less susceptible to disruption of overheating. 4) The emulsifying capacity (EC) of SPI was correlated positively to the solubility of protein at ${\mu}=0$. At pH of the isoelectric point of SPI (pH 4.6), EC increased as concentration of sodium chloride increased. Using model system$(mixing\;speed:\;12,000\;r.p.m.,\;oil\;addition\;rate:\;0.9\;ml/sec,\;and\;temperature\;:\;20{\pm}1\;^{\circ}C)$, the maximum EC of SPI was found to be 47.2 ml of oil/100 mg protein, at the condition of pH 8.7 and ${\mu}=0.6$. The milk casein had greater EC than SPI at lower ionic strength while the EC of SPI was the same as milk casein at higher ionic strength. 5) The shaking test was used in determining the foam-ability of proteins. Progressively increasing SPI concentration up to 5 % indicated that the maximum protein concentration for foaming capacity was 2 %. Sucrose reduced foam expansion slightly but enhanced foam stability. The results of comparing milk casein and egg albumin were that foaming properties of SPI were the same as egg albumin, and better than milk casein, particularly in foam stability.

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Sorption Efficiency of the Bamboo Charcoal to Remove the Cesium in the Contaminated Water System (오염수계 내 세슘 제거를 위한 대나무 활성탄의 흡착효율 규명)

  • Ahn, Joungpil;Lee, Minhee
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.87-97
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    • 2018
  • The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.

Comparison of chronic disease risk by dietary carbohydrate energy ratio in Korean elderly: Using the 2007-2009 Korea National Health and Nutrition Examination Survey (한국 노인 식사의 탄수화물 에너지비에 따른 만성질환 위험성 비교: 2007~2009년 국민건강영양조사 자료 이용)

  • Park, Min Seon;Suh, Yoon Suk;Chung, Young-Jin
    • Journal of Nutrition and Health
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    • v.47 no.4
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    • pp.247-257
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    • 2014
  • Purpose: It is reported that most senior people consume a high carbohydrate diet, while a high carbohydrate diet could contribute to the risk of chronic disease. The aim of this study is to determine whether a high carbohydrate diet can increase the risk of chronic disease in elderly Koreans. Methods: Using the 2007-2009 Korean National Health Nutrition Examination Survey data, out of a total of 3,917 individuals aged 65 and above, final 1,535 subjects were analyzed, divided by dietary carbohydrate energy ratio into two groups of moderate carbohydrate ratio (MCR, 55-70%) and excessive carbohydrate ratio (ECR, > 70%). All data were processed after the application of weighted value, using a general linear model or logistic regression. Results: Eighty one percent of elderly Koreans consumed diets with carbohydrate energy ratio above 70%. The ECR group included more female subjects, rural residents, lower income, and lower education level. The ECR group showed lower waist circumference, lower diastolic blood pressure, and lower frequency of consumption of meat and egg, milk, and alcohol. The intake of energy and most nutrients, with the exception of fiber, potassium, vitamin A, and carotene, was lower in the ECR group compared to the MCR group. When analyzed by gender, the ECR group showed lower risk of dyslipidemia in male and obesity in female subjects, even though the ECR group showed low intake of some nutrients. No difference in the risk of hypertension, diabetes, and anemia was observed between the two groups in male or female subjects. Conclusion: This result suggested that a high carbohydrate diet would not be a cause to increase the risk of chronic disease in the elderly. Further study is needed in order to determine an appropriate carbohydrate energy ratio for elderly Koreans to reduce the risk of chronic disease.