• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.299-306
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• 2016

In this study, new hydroxyapatite powder surface composites were investigated for protective effects against ultraviolet rays. Hydroxyapatite (HAp) is biocompatible and does not cause nebula phenomenon on skin. We investigated the surface modification of hydroxyapatite to improve UV block and skin usage. Dimethicone, lauroyl lysine, triethoxycaprylylsilane and silica were used as coating agents for the surface modification of HAp. To prepare the composite complex of the modified surface, the dimethicone, lauroyl lysine and triethoxycaprylylsilane were prepared by a dry process, and silica by a hydrothermal synthesis method. The HAp-silica was chosen as the best composite powder when measuring its sun protection levels. We investigated the characteristics of the surface of HAp-silica by SEM, particle size analyzer and energy dispersive spectrometry (EDS). Additionally, the stability in the formulation, UV block effect, and safety in BB creams were investigated. In conclusion, HAp-silica prepared by the modification of HAp complex surface improved the skin usage and UV block effect by enhancing the white cloudy phenomenon. These results indicate that HAp-silica may be used for UV block cosmetics.

• Journal of the Korea Society of Computer and Information
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• v.16 no.2
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• pp.141-151
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• 2011

This paper suggests the Facility Management System for plant factory promising to be a core technology of the agriculture in the future. This system makes diagnoses that status from sensors or facilities in the factory for exact operation and monitors the internal environment with the control status in real-time. It is expected that we could operate a plant factory safely and effectively by using the system. The system consists of the data management module, the context provider module, the context interpreter module, the service provider module, the data storage and user interface. The system provide with the failure diagnosis service, the facility control service, and the high-reliability monitoring service via the interactions between above modules. The failure diagnosis service determines whether the sensors or facility devices are in failure or not, and informs the administrator of their conditions. The facility control service is activated in case if the facilities need to be managed during the diagnosis for failure or malfunction processes. The high-reliability monitoring service provides the administrator with verified data through the failure diagnosis service. Then we confirmed that the suggested system operates correctly through the system simulation.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.412-425
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• 2012

Concrete Soil Erosion Control Dam, which blocks flow of debris flow in torrential stream, are reported to lose expected functions due to structural failure and collapses, caused by poor construction, material deterioration and external impacts. In this paper, an integrity assessment technique for debris barriers was proposed, which allows preliminary detection of problems inherent in debris barriers. The proposed integrity assessment technique is a non-destructive method based on SASW method, one of surface-wave tests. In this paper, a practical procedure and analysis guidelines in applying the SASW technique to debris barrier was proposed and its validity was verified using five decrepit debris barriers older than 20-year old. As a result, the SASW method was validated for the reliable grade evaluation method for concrete soil erosion control dam, and the resulting grades turned out to agree with the results determined by Sabang Associations.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.23-32
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• 2014

Purpose: This study was conducted in order to investigate the effect of Sargassum confusum extracts on the reduction of body fat for eight weeks in overweight women ($BMI{\geq_-}23kg/m^2$). Methods: Subjects were classified by double-blind randomized trial as the control group (C group, n = 14) and the Sargassum confusum extract supplementation group (SC group, n = 16), which consumed 12 tablets per day. Questionnaires related to their health status were assessed twice (week 0 and week 8). Their dietary intake status was evaluated by 24-recall method and body compositions were measured using a bioelectrical impedance analyzer. In addition, we assessed the anti-obesity effect and the occurrence possibility of health risk factors during the supplementation periods by hematological and clinical analysis of blood. Results: Waist circumference and body fat (%) were significantly decreased in the SC group. Serum leptin level was also significantly decreased in the SC group. Defecation frequency was significantly increased in the SC group. The above results indicate that Sargassum confusum extract supplementation improves overweight on visceral fat and blood leptin level by increasing bowel movement. These results imply a decrease of health risk factors in overweight women. Seven subjects withdrew from the study due to adverse events; however, no differences regarding adverse events were observed between the control and treatment group. Conclusion: Therefore, Sargassum confusum extract is a plausible effective agent for body fat reduction in humans.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.62-68
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• 2016

The feeder cable assembly is an automotive part used for telecommunication. If it malfunctions, the control and safety of the automobile can be put at risk. ALT (Accelerated Life Testing) is a testing process for products in which they are subjected to conditions (stress, strain, temperatures, etc.) in excess of their normal service parameters in an attempt to uncover faults and potential modes of failure in a short amount of time. Failure is caused by defects in the design, process, quality, or application of the part, and these defects are the underlying causes of failure or which initiate a process leading to failure. Thermal shock occurs when a thermal gradient causes different parts of an object to expand by different amounts. Thermal shock testing is performed to determine the ability of parts and components to withstand sudden changes in temperature. In this research, the main causes of failure of the feeder cable assembly were snapping, shorting and electro-pressure resistance failure. Using the Coffin-Manson model for ALT, the normal conditions were from Tmax = $80^{\circ}C$ to Tmin = $-40^{\circ}C$, the accelerated testing conditions were from Tmax = $120^{\circ}C$ to Tmin = $-60^{\circ}C$, the AF (Acceleration Factor) was 2.25 and the testing time was reduced from 1,000 cycles to 444 cycles. Using the Bxlife test, the number of samples was 5, the required life was B0.04%.10years, in the acceleration condition, 747 cycles were obtained. After the thermal shock test under different conditions, the feeder cable assembly was examined by a network analyzer and compared with the Weibull distribution modulus parameter. The results obtained showed good results in acceleration life test mode. For the same reliability rate, the testing time was decreased by a quarter using ALT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1650-1662
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• 2014

This study aimed to develop smartphone application contents for the medication reconciliation of high-alert medications and to evaluate the satisfaction for this application. The xcode 4.5 and ios 6.1 SDK(software development kit) were used for constructing screen of the system. After implementation during 4 weeks, thirty five ICU(Intensive Care Unit) nurses were asked function related, contents related, and usage related satisfaction using 12 items. And differences of satisfaction according to the number of daily use and the frequency of use were evaluated. Data were analyzed using descriptive analysis, ANOVA with the SPSS 18.0. We developed the formula for drug dosage calculation, the alarming procedure, and the information of the high alert medication. In the satisfaction items, the mean score of 'This application is helpful to perform drug dosage calculation' was 3.14. However, 'I satisfy this application' was relatively low as 2.94. There were no differences in satisfaction according to the daily use and frequency of use. Based on the results of this study, more advanced smartphone application for medication reconciliation of high-alert medications will provide an important platform for patient safety.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.271-279
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• 2019

In extreme environment regions, unmanned rovers equipped with various sensors and devices are being developed for long-term exploration on behalf of humans. On the other hand, due to the harsh weather conditions and rough terrain, the rover camera has limited visible distance and field of view. Therefore, the rover cameras should be located for safe navigation and efficient terrain mapping. In this regard, to minimize the cost and time to manufacture the camera system on a rover, the simulation method using the rover design is presented to optimize the camera locations on the rover efficiently. In the simulation, a simulated terrain was taken from cameras with different locations and angles. The visible distance and overlapped extent of camera images, and terrain data accuracy calculated from the simulation were compared to determine the optimal locations of the rover's cameras. The simulated results will be used to manufacture a rover and camera system. In addition, self and system calibrations will be conducted to calculate the accurate position of the camera system on the rover.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.437-445
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• 2020

Smoke grenades are the primary means of protection used by tanks to disrupt enemy detection systems. Such smoke grenades are a critical factor that determines the survival of tanks in the engagement of ground weapon systems, but it can only be used once. Owing to its destructive property, the performance and safety of the smoke grenade cannot be confirmed prior to use. Therefore, the reliability of smoke grenades can be evaluated through various tests during the storage period. This paper presents the results of estimating the reliability and shelf life of IR screening smoke grenade launchers based on the result of the Ammunition Stockpile Reliability Program conducted in 2019. Among the smoke grenade launcher lots currently stored, 16 lots and samples were selected for each year of manufacture and tested. The reliability and shelf life were estimated by examining the number of defects and the change in quality characteristics of each test item. The results of this study can be used to assess the reliability of the smoke grenade launchers and to improve the quality of manufacturing sites.

• Journal of radiological science and technology
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• v.34 no.1
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• pp.35-41
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• 2011

Total implanted central venous port (TIAP, Chemoport) is widely used in oncology patients because it does not require external dressing and restricts patient activity. Chemoport only requires monthly flushes of heparinized saline to keep the patency of the catheter and probably less prone to infectious complications than tunneled catheter. Despite the extensive use of permanent central venous access in oncology patients, there are only few reports about clinical experience of the Groshong catheter. The purpose of this study is to compare the complication rate between the traditional open-ended (non-valved) chemoports and valved chemoports (Groshong catheter connected to TIAP). During 5 years (Jan 2006 to May 2010), 438 patients received chemoport insertion procedure in our interventional radiology department. Among them 30 patients was referred to our department for problematic chemoports. We compared the cause of problematic chemoports between two types of chemoports (valved, vs. non-valved). Valved chemoports had higher referral rates than non-valved chemoports. When there is a need to insert valved port, different method of insertion and maintenance procedure seems to be necessary. More than 20 ml of flusing with heparinized saline after blood sampling could be a good suggestion. Adequate care of chemoport is essential for long patency. Also following the guideline from the manufacturing company is necessary.

• Land and Housing Review
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• v.3 no.4
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• pp.315-322
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• 2012

Recently multifaceted advantages of urban agriculture are emerging in civil society and related policy arena such as food safety, environment, and social welfare. This study tried an estimation of residents' willingness-to-pay for urban farming to examine feasibility of using part of urban green infrastructure as urban farm (e.g. allotment garden). A survey targeting Bundang and Dontan new-town residents was carried out and willingness-to-pay for urban farm rental was estimated by contingent valuation method (CVM). The estimated rent was cross-checked with the rental cost and travel cost paid by hobby farm users in the outskirt of metropolitan area. The result of this study showed that the potential demand for urban farming is ample if urban farms or allotment gardens are planned within new development areas. That is, 72.6 percent of new-town residents questioned had intention of using allotment garden within urban parks and green spaces. Estimated willingness-to-pay for renting a plot, $16.5m^2$ of urban farm, was about 236,000 won(KRW), which is higher than rent for a plot of allotment garden which is located out of city. Variables which were statistically significant to estimated willingness-to-pay for urban farming were sex, age, and occupation of respondents, among other explanatory socio-demographic variables, while expected frequency and duration of visit to urban farm were insignificant.