• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.1
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• pp.67-75
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• 2014

A full-scale static test for a composite structure small aircraft (KC-100) was conducted in the KARI. The test includes 15 full-scale test and 7 local test conditions. Test requirements with test schedule, test article with dummy structures, test load generation, test system, and equipment are introduced for the test. Test load data of the 1st test condition(U1) was analyzed to evaluate an accuracy of load control for the test. The analysis results show that load data obtained during test were within tolerance of Static Null Pacing Error(SNPE) and the error value of load control was 8.6N. The error of load controls for the full-scale static test using dozens of actuators was calculated by a method suggested by authors. Test data for all other test conditions is also shown in this paper. Finally, reactions measured from restraint system of the U1 test condition show that the reaction changes as load increment. The factors which may change the change of reactions for a full-scale static test are introduced in this study.

• Spatial Information Research
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• v.14 no.4 s.39
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• pp.363-377
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• 2006

Mean annual soil loss was calculated and critical soil erosion areas were identified for the Congaree River Basin in South Carolina, USA using the Revised Universal Soil Loss Equation (RUSLE) model. In the RUSLE model, the mean annual soil loss (A) can be calculated by multiplying rainfall-runoff erosivity (R), soil erodibility (K), slope length and steepness (LS), crop-management (C), and support practice (P) factors. The critical soil erosion areas can be identified as the areas with soil loss amounts (A) greater than the soil loss tolerance (T) factor More than 10% of the total area was identified as a critical soil erosion area. Among seven subwatersheds within the Congaree River Basin, the urban areas of the Congaree Creek and the Gills Creek subwatersheds as well as the agricultural area of the Cedar Creek subwatershed appeared to be exposed to the risk of severe soil loss. As a prototype model for examining future effect of human and/or nature-induced changes on soil erosion, the RUSLE model customized for the area was embedded into ESRI ArcGIS ArcMap 9.0 using Visual Basic for Applications. Using the embedded model, users can modify C, LS, and P-factor values for each subwatershed by changing conditions such as land cover, canopy type, ground cover type, slope, type of agriculture, and agricultural practice types. The result mean annual soil loss and critical soil erosion areas can be compared to the ones with existing conditions and used for further soil loss management for the area.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.391-398
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• 2005

The outbound containers in a container terminal are classified into a few groups by their weights and stocked separately in a yard for easy and efficient handling. In order to maintain the balance of a ship during loading, containers of heavier weight groups should be fetched out of a yard and loaded onto the ship before those of lighter weight groups. However, the weight information used to determine the weight group is usually imprecise. Therefore stacks will actually be filled with mixture of different weight groups and rehandlings are unavoidable during loading operation. This paper presents a method for estimating the number of rehandlings caused by imprecise information and a scheme for generating a simple but efficient slot assignment rule. Experiments have shown that a rule generated by the proposed method can reduce the number of rehandlings by about 20%compared to the traditional slot assignment method which stacks only the containers of the same weight group in a single stack.

• Journal of Life Science
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• v.27 no.6
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• pp.702-707
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• 2017

Insects and their extract have been traditionally used as medicinal resources in Asia. Recently, Gryllus bimaculatus and the larva of Tenebrio molitor, Protaetia brevitarsis, and Allomyrina dichotoma were enlisted as general food ingredients by Korean Ministry of Food and Drug Safety. As the interest in these insects is growing, the detailed investigation is needed for the standardization of suitable and safe rearing techniques. This survey was conducted via personal interviews about edible insect rearing farms in Korea. The basic feed is fermented oak sawdust for P. brevitarsis and A. dichotoma and wheat bran for T. molitor. The various feed additives are blended with each farm's own recipes. The overall growth condition, including sawdust fermentation method, feeding period, and rearing density, varies among the investigated farms. It seems that weight of last instar larva was correlated with the rearing density and duration of the larval period. The heavy metal contents were analyzed after 48 hour starvation and they were very small amount or not detected in investigated insects. We believe that the present data will contribute to develop and standardize the safe rearing techniques of edible insects in Korea.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.375-380
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• 2017

This paper reports the results of an acceleration test to predict the contact-induced failure that could occur at the cylinder-to-hole joint for the fuel rod of a sodium-cooled fast reactor (SFR). To incorporate the fuel life of the SFR currently under development at KAERI (around 35,000 h), the acceleration test method of reliability engineering was adopted in this work. A finite element method was used to evaluate the flow-induced vibration frequency and amplitude for the test parameter values. Five specimens were tested. The failure criterion during the life of the SFR fuel was applied. The S-N curve of the HT-9, the material of concern, was used to obtain the acceleration factor. As a result, a test time of 16.5 h was obtained for each specimen. It was concluded that the $B_{0.004}$ life would be guaranteed for the SFR fuel rods with 99％ confidence if no failure was observed at any of the contact surfaces of the five specimens.

• Korean Journal of Optics and Photonics
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• v.20 no.2
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• pp.128-133
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• 2009

In this paper, an optical touch panel device is newly proposed, with operating principle based on the optical coupling between a pointing pen having a built-in light source and perpendicularly crossed optical waveguide arrays. In order to enable an external light to couple into a waveguide core, the auxiliary pyramidal structures are introduced into all intersecting points located periodically along optical waveguides. The shape is optimized for minimizing the unwanted propagation loss due to the same structure by a ray tracing method. For the optical waveguide with the size of $50{\times}50{\mu}m^2$, the bottom width, height, and slope angle of the optimized pyramidal structure are $50{\mu}m$, $22.5{\mu}m$, and $42^{\circ}$, respectively. The optical coupling efficiency of about 97.8% and the average propagation loss of 0.3 dB/mm were achieved for the optimized touch panel. Finally, it is found from the tolerance analysis that tilting of the pen up to ${\pm}12^{\circ}$ can be allowed.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.137-144
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• 2016

The ultimate research goal of the current study was a development of hydrolyzed whey protein powder (7%-GNANA) manufactured with normal content of sialic acid, a marker compound, that is naturally occurring at 7% concentration in GMP obtained from the milk protein. GMP is a safe food, used worldwide in infant and baby foods, etc. The test substance was prepared using (7% sialic acid containing) GMP as a raw material, and then using alcalase, an enzyme approved as a food additive, after separation of sialic acid with 100% efficiency and 7%-GNANA (containing 7% sialic acid and protein; product name: HELICOBACTROL-7) provided by MEDINUTROL Inc. (Korea). Bacterial reverse mutation (Ames) test was conducted in accordance with GLP Guideline using the test substance specified above. To identify its mutagenic potential against microorganisms, histidine auxotrophic strains of Salmonella Typhimurium, TA98, TA100, TA1535, and TA1537, and tryptophan auxotrophic strain of Escherichia coli, WP2uvrA, were used. The bacterial reverse mutation (Ames) test was performed by dividing the test substances into five different concentration groups (0, 61.7, 185, 556, 1,670, $5,000{\mu}g/plate$). Results of this experiment did not reveal repetitive increase of colony generating values or positive criteria for reverse mutagenicity for any concentration of test substances in any of the five strains, regardless of the presence of a metabolic activation system, and no dose-dependency was identified. In conclusion, the safety of 7%-GNANA test substance was verified by bacterial reverse mutation test conducted before registration of 7%-GNANA as a food additive.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.209-214
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• 1992

Residue of Propineb in Sesame(Sesamum indicum L.) seed was determined to establish an index for the safety use of Propineb to Sesame. Evaluation was made on residual concentration of Propineb in Sesame seed as a function of application frequency and date when the mixed formulations of Propineb(56%), protectant fungicide, and Oxadixyl(8%), contact fungicide, were sprayed into Sesame leaves. Level of Propineb treatment was $0.028g/m^2$ with various combinations of application time from three to sixty days before harvest. Results are summarized as followings. 1. Recovery percentages of Propineb from Sesame seed were ranged from 84 to 96, and the minimum detectable limit of Propineb with the method employed in this experiment was 0.03mg/kg. 2. Residues of Propineb in Sesame seed were in the ranges of 0.14 to 1.38mg/kg, varying with frequency and date of Propineb application. 3. Residues of Propineb increased as increasing application frequency of Propineb or as being application date closer to harvest time. 4. Residue of Propineb in Sesame seed was decreased with time, showing to be fitted to the first-order kinetics. 5. Residues of Propineb in Sesame seen were, irresepective of treatments, lower than 2mg/kg, the Maximum Residue Limit(MRL) established by FAO/WHO. 6. Half-life of Propineb determined in this experiment was ranged from 12 to 16 days.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.299-307
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• 2007

Changes in nitrite content, TBARS content and color of meat products during storage were examined as part of studies addressing the reduction of residual nitrite and to ensure the safety of meat products. All 4 kinds of domestic meat product tested, Vienna sausage, bacon, smoked-ham and Dduggalbi, manufactured by C and L domestic companies had very low contents of residual nitrite, for below the legal tolerance limit of 70 ppm, and the residual nitrite decreased with storage. The reduction in nitrite content differed with each product, showing the greatest reduction in Vienna sausage and the least reduction in bacon when stored at $4^{\circ}C$. On the other hand, when stored at $-20^{\circ}C$, the nitrite content of bacon decreased more rapidly than the other meat products. The results of this study show that the nitrite content of meat products decreases during storage, and that the rate of decrease is quite dependent on the storage temperature. In addition, the nitrite contents of most domestic meat products are very low compared to the legal limits, thus the health risks of nitrite in meat products might not be of great concern. More research on the reduction of residual nitrite and on the development of alternatives to nitrite is necessary.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.122-130
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• 2008

In many applications of wireless sensor networks, sensed data can be classified either normal or urgent data according to its time criticalness. Normal data such as periodic monitoring is loss and delay tolerant, but urgent data such as fire alarm is time critical and should be transferred to a sink with reliable. In this paper, by exploiting these data characteristics, we propose a novel energy-efficient data-aware routing protocol for wireless sensor networks, which provides a high reliability for urgent data and energy efficiency for normal data. In the proposed scheme, in order to enhance network survivability and reliability for urgent data, each sensor node forwards only urgent data when its residual battery level is below than a threshold. Also, the proposed scheme uses different data delivery mechanisms depending on the data type. The normal data is delivered to the sink using a single-path-based data forwarding mechanism to improve the energy-efficiency. Meanwhile, the urgent data is transmitted to the sink using a directional flooding mechanism to guarantee high reliability. Simulation results demonstrate that the proposed scheme could significantly improve the network lifetime, along with high reliability for urgent data delivery.