• Title/Summary/Keyword: Adjusted Means

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Determination of Tumor Boundaries on CT Images Using Unsupervised Clustering Algorithm (비교사적 군집화 알고리즘을 이용한 전산화 단층영상의 병소부위 결정에 관한 연구)

  • Lee, Kyung-Hoo;Ji, Young-Hoon;Lee, Dong-Han;Yoo, Seoung-Yul;Cho, Chul-Koo;Kim, Mi-Sook;Yoo, Hyung-Jun;Kwon, Soo-Il;Chun, Jun-Chul
    • Journal of Radiation Protection and Research
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    • v.26 no.2
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    • pp.59-66
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    • 2001
  • It is a hot issue to determine the spatial location and shape of tumor boundary in fractionated stereotactic radiotherapy (FSRT). We could get consecutive transaxial plane images from the phantom (paraffin) and 4 patients with brain tumor using helical computed tomography(HCT). K-means classification algorithm was adjusted to change raw data pixel value in CT images into classified average pixel value. The classified images consists of 5 regions that ate tumor region (TR), normal region (NR), combination region (CR), uncommitted region (UR) and artifact region (AR). The major concern was how to separate the normal region from tumor region in the combination area. Relative average deviation analysis was adjusted to alter average pixel values of 5 regions into 2 regions of normal and tumor region to define maximum point among average deviation pixel values. And then we drawn gross tumor volume (GTV) boundary by connecting maximum points in images using semi-automatic contour method by IDL(Interactive Data Language) program. The error limit of the ROI boundary in homogeneous phantom is estimated within ${\pm}1%$. In case of 4 patients, we could confirm that the tumor lesions described by physician and the lesions described automatically by the K-mean classification algorithm and relative average deviation analyses were similar. These methods can make uncertain boundary between normal and tumor region into clear boundary. Therefore it will be useful in the CT images-based treatment planning especially to use above procedure apply prescribed method when CT images intermittently fail to visualize tumor volume comparing to MRI images.

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Influence of Smoking on Matrix Metalloproteinase-9 in the Gingival Crevicular Fluid (흡연이 치은열구액 내 Matrix Metalloproteinase-9에 미치는 영향)

  • Hwang, Soo-Jeong;Kim, Young-Kwon;Yang, Seong-Ju;Cho, Hyun-Jeong
    • Journal of dental hygiene science
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    • v.11 no.4
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    • pp.339-344
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    • 2011
  • Matrix metalloproteinase(MMP)-9 is considered important in tissue destruction in periodontitis. The aim of this study was to investigate the influence of smoking on MMP-9 in the gingival crevicular fluid(GCF). GCF samples in upper incisors area from 332 male subjects were collected after the informed consent. The dental examination included the assessment of oral hygiene, gingival inflammation and probing pocket depth. A quantitative assessment of MMP-9 levels in GCF was performed utilizing and immunological procedure. The mean MMP-9 concentrations found in GCF of smokers(30.86 ng/ml) and quit-smokers(29.82 ng/ml) differed from non-smokers(11.33 ng/ml), adjusted by age, gingival index and Community periodontal index(p<0.001). Smoking seems to influence MMP-9 in GCF regardless of gingival inflammation and age. It means smoking can destruct the periodontal tissue for itself.

Acidification of pig slurry effects on ammonia and nitrous oxide emissions, nitrate leaching, and perennial ryegrass regrowth as estimated by 15N-urea flux

  • Park, Sang Hyun;Lee, Bok Rye;Jung, Kwang Hwa;Kim, Tae Hwan
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.3
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    • pp.457-466
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    • 2018
  • Objective: The present study aimed to assess the nitrogen (N) use efficiency of acidified pig slurry for regrowth yield and its environmental impacts on perennial ryegrass swards. Methods: The pH of digested pig slurry was adjusted to 5.0 or 7.0 by the addition of sulfuric acid and untreated as a control. The pig slurry urea of each treatment was labeled with $^{15}N$ urea and applied at a rate of 200 kg N/ha immediately after cutting. Soil and herbage samples were collected at 7, 14, and 56 d of regrowth. The flux of pig slurry-N to regrowth yield and soil N mineralization were analyzed, and N losses via $NH_3$, $N_2O$ emission and $NO_3{^-}$ leaching were also estimated. Results: The pH level of the applied slurry did not have a significant effect on herbage yield or N content of herbage at the end of regrowth, whereas the amount of N derived from pig slurry urea (NdfSU) was higher in both herbage and soils in pH-controlled plots. The $NH_4{^+}-N$ content and the amount of N derived from slurry urea into soil $NH_4{^+}$ fraction ($NdfSU-NH_4{^+}$) was significantly higher in in the pH 5 plot, whereas $NO_3{^-}$ and $NdfSU-NO_3{^-}$ were lower than in control plots over the entire regrowth period. Nitrification of $NH_4{^+}-N$ was delayed in soil amended with acidified slurry. Compared to non-pH-controlled pig slurry (i.e. control plots), application of acidified slurry reduced $NH_3$ emissions by 78.1%, $N_2O$ emissions by 78.9% and $NO_3{^-}$ leaching by 17.81% over the course of the experiment. Conclusion: Our results suggest that pig slurry acidification may represent an effective means of minimizing hazardous environmental impacts without depressing regrowth yield.

A Study on the Possibility of Using UAV Stereo Image for Measuring Tree Height in Urban Area (도심지역 수목 높이값 측정을 위한 무인항공기에서 취득된 스테레오 영상의 활용 가능성 고찰)

  • Rhee, Sooahm;Kim, Soohyeon;Kim, Taejung
    • Korean Journal of Remote Sensing
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    • v.33 no.6_2
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    • pp.1151-1157
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    • 2017
  • Street Trees is an important object for urban environment improvement. Especially the height of the trees needs to be precisely measured as a factor that greatly influences the removal of air pollutants in the Urban Street Canyons. In this study, we extracted the height of the tree based on the stereo image using the precisely adjusted UAV Images of the target area. The adjustment of UAV image was applied photogrammetric SfM (Structure from motion) based on the collinear condition. We measured the height of the trees on the Street Canyon using stereoscopic vision on stereo plotting system. We also acquired the height of the building adjacent to the street trees and the average height of the road surface was calculated for accurate measurement of the height of each object. Through the visual analysis with the plotting operation system, it was possible to measure height of the tree and to calculate the relative height difference value with building quickly. This means that the height of buildings and trees can be calculated without making a 3D point cloud of UAV and it has the advantage of being able to utilize non-experts. In the future, further studies for semiautomatic/automation of this technique should be performed. The development and research of these technologies is expected to help to understand the current status of environmental policies and roadside trees in urban areas.

A Study on Serum Lipid Levels and Dietary Fat and Fatty Acid Intakes in Primary School Children (초등학교 아동의 혈청 지질 상태 및 지방 섭취에 관한 연구)

  • 김은경
    • Journal of Nutrition and Health
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    • v.31 no.2
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    • pp.166-178
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    • 1998
  • The purpose of this study was no investigate serum lipid levels of primary school children and to estimate their intakes of total fat and fatty acids. Subjects fasting blood samples were obtained and analyzed for serum triglycerides(TG), total cholesterol(Chol) and high density lipoprotein-cholesterol (HDL-Chol). Low density lipoprotein cholesterol (LDL-Chol), LDL-Chol/HDL-Chol ratio(LPH), and atherogenic index(AI) were calculated,. Dietary intake of nutrients was assessed by means of a 24-hour recall method using food models and other measuring tools . The serum levels of TG, Chol and LDL-Chol in girls were higher than those in boys, but the serum HDL-Chol level of girls was lower than that of boys. As the degree of obesity increased, the serum TG level of girls was lower than that of boys. As the degree of oesity increased , the serum TG level of girls increased. The serum LDL-Chol level was higher in obese boys than in normal ones. Percentage s of subjects at risk of cardiovascular disease based on corresponding criteria of TG, Chol,HDL-CHol and LDL-Chol were 25.9%, 7.6%, 20.7% and 10.1%, respectively. The serum TG level of children provided with the national school lunch program(NSLP) was lower than that of children without NLSP. The total fat intake of boys was higher than that of girls, but calorie-adjusted fat intake became similar between the two groups. Intakes of polyunsaturated fatty acids(PUFA), monounsaturated fatty acids(MUFA) and saturated fatty acids(SFA) were 13.3$\pm$9.5g, 16.1$\pm$9.3g and 21.4$\pm$14.2g in boys, respecitively , and 12.6$\pm$11.3g, 15.3$\pm$9.7g and 19.9$\pm$13.1g in girls, respectively . The ratios of polyunsaturated /monoun-saturated /saturated /saturated fatty acids(P/M/S) in boys and girls were 0.7/0.8/1.0 and 0.8/0.8/1.0 respectively. The ratios of $\omega$6/$\omega$3 fatty acids in boys and girls were found to be 12.1 /1.0 and 8.6/1.0 , respectively. These results indicated the urgent need of nutritional education in primary schools to prevent further increase in childhood obesity and hyperlipidemia . Therefore, this study will contribute to the establishment of dietary guidelines and health recommendation for school children.

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Psychometric Charateristics of Occupational Low Back Pain Patients (일부 재해성 요부손상 환자의 심리적 특성)

  • Ha, Mi-Na;Cho, Soo-Hun;Kweon, Ho-Jang;Han, Sang-Hwan;Joo, Young-Soo;Pack, Nam-Jong
    • Journal of Preventive Medicine and Public Health
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    • v.28 no.3 s.51
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    • pp.715-725
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    • 1995
  • This study was done for identifying the factors which affect psychologic symptoms of low back(LBP) patients. The study subjects were 43 work-related low back pain patients, 28 work-related non-low back pain patients and 47 general low back injury patients. The study materialis SCL 90-R for checking psychologic symptoms and questionnaire for obtaining general information about the subjects. The data were analyzed by model of analysis of covariance adjusted by several variables such as gender, age, education and marital status and then compared the least square means of symptom score between groups. To identify the factors that affect psychologic symptom, duration of suspension, return to work and interaction factor of these two variables were analyzed by multivariate model and we calcuated partial correlation coefficient of these variables. As a result, work-related LBP patients showed higher score of symptoms in somatization, depression and psychosis than work-related non-LBP and non-work-related LBP. Duration of suspension and return to work were significant explanatory variables for psychologic symptom score of work-related LBP. Then, we may conclude that the treatment and rehabilitation programe for work-related LBP should cover the strategy of early return to work.

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A study on lighting system for LED color temperature control using wireless communication and smartphone (무선 통신과 스마트폰을 이용한 LED 색온도 제어 조명 시스템에 관한 연구)

  • Hong, Young-Jin;Lim, Soon-Ja;Lee, Wan-Bum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.72-77
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    • 2017
  • Lighting systems in modern society has been developed using a combination of IT technology and LED lighting for the purpose of bringing about changes in human-centered natural lighting and to take advantage of the efficient management and energy saving of LED lighting. In this paper, we propose an LED lighting control system that can control the color temperature and brightness of LED lighting composed of 3000K Warm LEDs and 6000K Cool LEDs by using an Arduino Due and wireless communication technology such as Bluetooth and Zigbee. The Arduino Due allows the color temperature of the lighting to be adjusted in several steps by controlling the duty rate and enables many lights to be controlled using Zigbee communication capable of 1: N multiple communication. By using Bluetooth communication, it is possible to easily control the LED lighting by means of a smartphone application, thereby enhancing the convenience for the user. The wireless communication based LED lighting control system implemented in this study cannot only provide human-centered lighting through its color temperature control from 3067K to 5960K and illumination control, but can also reduce the power consumption and be used as a natural-friendly lighting system.

Development of Methodology for the Analysis of Level-of-Service of Non-Controlled Intersections (무통제 교차로의 서비스수준 결정 방법론에 관한 연구)

  • 김정현;김영찬
    • Journal of Korean Society of Transportation
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    • v.21 no.5
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    • pp.31-40
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    • 2003
  • Unsignalized intersections are classified into two-way-stop-controlled(TWSC) and all-way-stop-controlled(AWSC) intersections for the analysis of capacity and level of service. There is no AWSC intersection in Korea, but non-controlled intersections are common. Non-controlled intersections are operated only by the driver's decision without any control. However, the study for the analysis of capacity and level of service of the non-controlled intersection has been rare. As the first stage research, this study aims to determine the measure-of-effectiveness (MOE) for the performance evaluation of non-controlled intersections. The relationships between traffic volume and the intersection passing time (delay) and number of conflicts on each intersection are analyzed. It was found that the number of conflicts were more sensitive to the traffic volume compared with the delay. It means that number of conflicts can be the MOE for the performance of non-controlled intersection. The analysis of the number of conflicts and traffic volume showed a linear relationship, so that traffic volume can also be an MOE. The level of service of non-controlled intersection can be determined with either of the MOE's. Since the performance is also influenced by the ratio of traffic volumes of crossing streets, the traffic volume should be adjusted by the ratio. The capacity of non-controlled intersection was suggested to be 2,000veh/hr referring that of AWSC intersection in the USHCM. The criteria was suggested by evenly dividing the traffic volumes based on the capacity.

Image Enhancement and Clinical Evaluation in Digital Chest Radiography (디지털 방사선 흉부영상의 영상개선과 임상평가)

  • Kim, Sung-Hyun;Suh, Tae-Suk;Choe, Bo-Young;Lee, Hyoung-Koo
    • Progress in Medical Physics
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    • v.19 no.3
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    • pp.143-149
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    • 2008
  • The aim of this study is to suggest the method for image enhancement of digital chest radiograph and evaluate clinically the quality of the resultant image. A nonlinear iterative filter was developed in order to reduce quantum noise preserving edge. Dynamic range was adjusted and adaptive image enhancement was performed based on the property of anatomic region and the degree of compatibility with neighboring pixels. The lung fields were enhanced appropriately to visualize effectively vascular tissue, bronchus and lung tissue with the desired mediastinum enhancement. Clinic evaluation was performed by three radiologists with at least 8 years experience. The anatomic regions of 11 in PA and 9 in Lateral were observed carefully in each 100 radiographs according to ITU (International Telecommunication Union) recommendation 500 protocol. The result showed the mean 3.4 between good and adequate. This means that the clinical utility of the image quality is enough. In this study, image enhancement was carried out considering image display device and human perceptual system to prevent the loss of useful anatomic information. In order to increase the diagnostic accuracy in digital radiograph, the continuous study on image enhancement is needed.

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A Study of the Fluctuation factors and Model of Daily Visitors of National Park (국립공원의 이용자수 변동요인 및 추정모형에 관한 연구)

  • 안성노
    • Journal of the Korean Institute of Landscape Architecture
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    • v.17 no.2
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    • pp.27-39
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    • 1989
  • The purpose of this study is to prove the factors affecting the fluctuation of daily visitors in five mountainous national park(Kayasan, kyeryongsan, Naejangsan, Soraksan, Songnisan), and to analyze the relationship between these factors and daily visitors in Korea. "Three Factors and Nine Categories"(Aoki, K. & Aoki, Y. : 1974, 1979) has been applied to this study, and statistical analysis method was carried out by computer program SAS and SPSS. The number of daily visitors is calculated based on the data of "Daily entrance ticket sale report" by administration office in each national park. The scope of time period is during the last 5years(1982∼1986: 1825days) and the results were as follows: 1) There were significant differences in the number of daily visitors of each national park among months, days of a week and weather-the same as the previous study of urban park case. But it wold be better for their category classification to be adjusted according to the fluctuation pattern of each national park. 2) The peak of monthly visitors comes in May(Kayasan, Soraksan, Songnisan) or October(Kyeryongsan, Naejangsan). These months are specified as group tour season. On the basis of monthly fluctuation pattern, Each national park were classified into seasonal type, that is, kayasan, Soraksan were proved to be three-season type(Spring, Summer, Autumn), Songnisan to be two-season type(Spring, Autumn), and Naejangsan to be one-season type(Autumn). 3) The weekly pattern differs from three category (weekday, weekend, holiday: Eom, Choi 1986) in the case of urban park study. And there is no significant difference in daily fluctuation pattern by weather (fine, cloudy and rainy day), but significant difference between snowy and the others. This result is due to the characteristics of visitors, which is, the major visits of national park are planned in a advance of the tour, therefore it is difficult to change the plan by the weather. 4) the result of correlation analysis showed that the most influential factor on national park use in Kayasan, Naejangsan, Soraksan and Songnisan is ′Monthly characters (M)′, on the contrary ′Day of week(D)′ in Kyeryongsan only. From the result, The more parks are resource-based, the more ′Monthly characters′-factor is supposed to affect the number of daily visitors rather than ′Day of the week′-factor. This means that kayasan, naejangsan, Sorakson and Songnisan are classified into resource-based type, but on the other hand Kyeryongsan should be classified into intermediate type.

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