• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.5
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• pp.405-412
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• 2015

This paper represents a filter design to estimate the airspeed of a spin-stabilized, trajectory-correctible artillery ammunition. Due to the limited power and space in operational point of view, the airspeed sensor is not installed, and thus the airspeed need to be estimated using limited sensor measurements. The only IMU measurements(three-axis specific forces and angular rates) are used in this application. The extended Kalman filter algorithm is applied since a linear filter can not cover the its wide operational range in airspeed and altitude. In the implementation of the EKF, the state and measurement equations are transformed into the no-roll frame for simple form of Jacobian matrix. The simulation study is conducted to evaluate the performance of the filter under various environment conditions of sensor noise and wind turbulence. In addition, the effect of the choice in filter design parameters, i.e. process error covariance matrices is analyzed on the performance of the estimation of airspeed and angular rates.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.395-400
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• 2015

Both Japan and Korea provide population-based screening programs. However, screening rates are much higher in Korea than in Japan. To clarify the possible factors explaining the differences between these two countries, we analyzed the current status of the cancer screening and background healthcare systems. Population-based cancer screening in Korea is coordinated well with social health insurance under a unified insurer system. In Japan, there are over 3,000 insurers and coordinating a comprehensive strategy for cancer screening promotion has been very difficult. The public healthcare system also has influence over cancer screening. In Korea, public healthcare does not cover a wide range of services. Almost free cancer screening and subsidization for medical cost for cancers detected in population-screening provides high incentive to participation. In Japan, on the other hand, a larger coverage of medical services, low co-payment, and a lenient medical audit enables people to have cancer screening under public health insurance as well as the broad range of cancer screening. The implementation of evidence-based cancer screening programs may be largely dependent on the background healthcare system. It is important to understand the impacts of each healthcare system as a whole and to match the characteristics of a particular health system when designing an efficient cancer screening system.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1557-1561
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• 2014

Background: Breast cancer is the most frequently diagnosed cancer in women and estimating its relative risks and trends of incidence at the area-level is helpful for health policy makers. However, traditional methods of estimation which do not take spatial heterogeneity into account suffer from drawbacks and their results may be misleading, as the estimated maps of incidence vary dramatically in neighboring areas. Spatial methods have been proposed to overcome drawbacks of traditional methods by including spatial sources of variation in the model to produce smoother maps. Materials and Methods: In this study we analyzed the breast cancer data in Iran during 2004-2008. We used a method proposed to cover spatial and temporal effects simultaneously and their interactions to study trends of breast cancer incidence in Iran. Results: The results agree with previous studies but provide new information about two main issues regarding the trend of breast cancer in provinces of Iran. First, this model discovered provinces with high relative risks of breast cancer during the 5 years of the study. Second, new information was provided with respect to overall trend trends o. East-Azerbaijan, Golestan, North-Khorasan, and Khorasan-Razavi had the highest increases in rates of breast cancer incidence whilst Tehran, Isfahan, and Yazd had the highest incidence rates during 2004-2008. Conclusions: Using spatial methods can provide more accurate and detailed information about the incidence or prevalence of a disease. These models can specify provinces with different health priorities in terms of needs for therapy and drugs or demands for efficient education, screening, and preventive policy into action.

• Analytical Science and Technology
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• v.23 no.5
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• pp.446-456
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• 2010

In this study, the performance characteristics of DNPH sampling were investigated in the collection and analysis of 5 carbonyl compounds (CC) in air using the cartridge products produced by three different makers. For these experiments, gaseous standards of 5 CCs were prepared to cover 9 concentration levels for each compound (33~2600 nmol). Some cartridge products exhibited relatively high blank values of acetaldehyde (AA) and propionaldehyde (PA). The recovery rates of all three cartridges showed moderate reduction as the molecular weight of CC increased. In addition, when the recovery rate was compared by percent error (%), the most stable patterns were achieved in the intermediate concentration range of 263~1312 nmol (in case of AA). The overall results of our study suggest that the optimal range of recovery for a given concentration range should be considered to obtain the most reliable data for the DNPH cartridge method.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.169-173
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• 2008

Purpose: Sacrococcygeal pilonidal sinus is a chronic inflammatory disease that mostly affects young people, which warrants surgical intervention. Although many surgical methods have been suggested, an optimal surgical method remains controversial because of high recurrence rates and postoperative complications. The objective of this study is to evaluate the results of wide excision and coverage with fasciocutaneous advancement flap for the treatment of sacrococcygeal pilonidal sinus, and to assess the usefulness of this method Methods: From May 1995 to October 2006, the authors treated 19 patients with the use of coverage with fasciocutaneous flap after wide excision. The results were evaluated regarding recurrence rates, complications, and the change in sensitivity of the gluteal region after surgery. The follow-up period was 7 to 142 months (mean, 76 months). All patients were male. Results: Postoperative complications were wound infection at the suction drain insertion site and skin necrosis around the suture margin in one case, respectively. During the follow up period, only one recurrence (5.3%) was seen in fifth postoperative month, which was successfully treated by the same operative procedure. There was no other complications such as seroma, hematoma, wound dehiscence and flap loss. Extensive scarring and anatomic distortion did not occur in the reconstructed area. In addition, sensitivity of the gluteal region did not diminish. The aesthetic results were satisfactory for all patients as well. Conclusion: The authors advocate that fasciocutaneous flap closure be a good alternative method to cover defects after the excision of sacrococcygeal pilonidal sinus.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.7
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• pp.3-12
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• 2004

The need to predict the rate of soil erosion, both under existing conditions and those expected to occur following soil conservation practice, has been led to the development of various models. In this study Morgan model especially developed for field-sized areas on hill slopes was applied to assess the rate of soil erosion using RS/GIS environment in the Dukchun river basin, one of two tributaries flowing into Jinyang lake. In order to run the model, land cover mapping was made by the supervised classification method with Landsat TM satellite image data, the digital soil map was generated from scanning and screen digitizing from the hard copy of soil maps, digital elevation map (DEM) in order to generate the slope map was made by the digital map (DM) produced by National Geographic Information Institute (NGII). Almost all model parameters were generated to the multiple raster data layers, and the map calculation was made by the raster based GIS software, IL WIS which was developed by ITC, the Netherlands. Model results show that the annual soil loss rates are 5.2, 18.4, 30.3, 58.2 and 60.2 ton/ha/year in forest, paddy fields, built-up area, bare soil, and upland fields respectively. The estimated rates seemed to be high under the normal climatic conditions because of exaggerated land slopes due to DEM generation using 100 m contour interval. However, the results were worthwhile to estimate soil loss in hilly areas and the more precise result could be expected when the more accurate slope data is available.

• Journal of Biosystems Engineering
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• v.43 no.3
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• pp.185-193
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• 2018

Purpose: The purpose of this study was to analyze the performance factors of a rotary impact-type thresher to develop a sesame and perilla thresher, specifically to analyze the cut length of the stems and the threshing rates based on the relationship between the blade velocity and feeding speed. Methods: The materials were dried within a range of 12.3-13.0% to test the impact cut by bending. The cut lengths of the perilla and sesame stems were categorized in 6 ranges (~7.0, 7.1-10.0, 10.1-13.0, 13.1-16.0, 16.1-20.0, 20.1- (cm)). For testing the cut length and threshing rate, the upward-rotating blade velocity was varied as 11.0 m/s, 13.5 m/s, and 22.3 m/s. Feeding speeds were changed from 0.1 m/s to 2.2 m/s by the inverter connected to the feed motor. The feed rate and threshing rates without cover-casing were evaluated with the factors of thresher testing. Results: The mean cut length of the stem decreased as the blade velocity increased and/or the feeding speed decreased. As the feed rate increased up to 17.5 g/s, the cut length distributions showed no significant difference. The threshing rate was 98.9% for sesame, and flexible according to the blade velocity and feeding speed of the perilla. Conclusion: Feeding material too fast could produce longer cut stem segments, therefore, a feeding speed less than 2.2 m/s is recommended. A blade velocity of 13.5 m/s is preferable for both sesame and perilla with regard to cut length and threshing rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.3
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• pp.139-143
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• 2016

Objectives: If teeth are missing, super-eruption of teeth in the opposing arch can occur in the area and can change the occlusal plane. When missing teeth are replaced with implants, the oral surgeon must determine whether or not the super-erupted teeth need to be treated in order to normalize the occlusal plane. In this study, we evaluated the clinical prognosis of dentition after implant placement and prosthetic treatment were completed in an occlusal plane altered by super-erupted teeth in the opposing arch without additional treatment of the super-erupted teeth. Materials and Methods: Twenty-two patients (9 males, 13 females) were treated with implants and prosthetics without addressing the super-erupted opposing dentition from April 2004 to August 2012 at Seoul National University Bundang Hospital. A total of 33 implants were placed. Values of crestal bone loss, survival rates, and surgical and prosthetic complications for an average of 29.6 months after prosthetic loading were recorded. Results: In one case, the cover screw was exposed after implant surgery. The mean crestal bone loss was $0.09{\pm}0.30mm$. Of the 33 implants, 31 survived, a survival rate of 93.94%. A prosthetic complication occurred in one case but functioned well after correction. Conclusion: Favorable clinical results from prosthetic complications, crestal bone loss, and implant survival rates were exhibited in implants next to a super-erupted opposing tooth.

• Journal of Microbiology and Biotechnology
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• v.31 no.7
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• pp.956-966
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• 2021

To prevent the outbreak of infectious diseases that inflict huge economic and social losses, domestic livestock farms and related facilities have introduced automatic and semiautomatic disinfectant solution-spraying systems for vehicles. However, the facility standards and specifications vary by manufacturer, and no scientific performance evaluation has been conducted. The puropose of this study is to develop physical and biological evaluation methods. Physical and biological appraisals were conducted using two types of disinfection facilities (tunnel- and U-type) and two types of vehicles (passenger car, truck). Water-sensitive paper was used to evaluate the physical performance values for the disinfection facilities. In addition, to assess their biological performance, carriers containing low-pathogenic avian influenza virus were attached to vehicles, and the viral reduction was measured after the vehicles moved through the facility. The tunnel-type had rates of coverage in the range of 70-90% for the passenger car and 60-90% for the truck. At least 4-log virus reduction after spraying for 1-5 min was shown for both vehicles. For the U-type facility evaluation, the coverage rates were in the range of 60-90% for the passenger car and at least 90% for the truck. More than 4-log viral reduction was estimated within a spraying time of 5 min. To reduce viruses on the surface of vehicles by at least 4 log within a short period, the disinfectant solution should cover at least 71% of the pathogens. In conclusion, we were able to assess the physical and biological performance criteria for disinfection facilities aboard transportation vehicles.

• Health Policy and Management
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• v.33 no.1
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• pp.40-54
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• 2023

Background: Based on the increase in the needs for convalescent rehabilitation medical services in Korea, this study aims to calculate the needs for rehabilitation services and examine its determinants for 229 regions. Methods: Claim data from the Health Insurance Review and Assessment Service were used to estimate patients who need to receive rehabilitation services, and data from various sources were also used for analysis. The number of cases and incidence rates of hospitalization related to convalescent rehabilitation were calculated to estimate the needs for services by region, and the results were visualized via a map. Multivariate regression and fixed effects regression using panel data were performed to identify the determinants of regional variation of the incidence rate. Results: First, the incidence rate of rural areas such as Jeolla-do, Gyeongsang-do, and Chungcheong-do was higher than urban areas (metropolitan cities). Second, the population, proportion of the elder, medical aid recipients, financial independence, traffic deaths, smoking, diabetes rate, and medical infrastructure correlated significantly with the incidence rate. Third, 'rho' values which mean the fraction of variance due to individual terms in panel data regression models were 0.965 and 0.976, respectively. Conclusion: The incidence rate of hospitalizations was correlated with most independent variables in this study and there is a gap between urban and rural areas. These regional disparities are fixed in our society. An improved regional convalescent rehabilitation system is suggested to cover the entire area including rural areas with a high rate of aging.