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Changes in Moisture Content and Quality of Oriental Hybrid Lily (Lilium oriental cv. Siberia) Cut Flowers during Storage at Cold and Dry Condition and Subsequent Exposure to Ambient Temperature (오리엔탈 나리 '시베리아' 절화의 포장내 건식저장 기간별 수분함량과 품질 변화)

  • Lee, Jung-Soo;Rhee, JuHee;Kang, Yun-Im;Choi, Ji Weon
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.23 no.1
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    • pp.27-36
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    • 2017
  • In order to determine the relationship between water content and flower qualities of oriental hybrid lily cv. 'Siberia' cut flower, flowers were subjected to dry and cold storage at $5^{\circ}C$ for 3, 6, and 12 days and subsequently exposed to ambient temperature ($26^{\circ}C$) in bottles with water for up to 16 days. Flowers stored at $22^{\circ}C$ in dry condition for 3 days were used as the control. Changes in fresh weight, moisture content, water balance, flowering stages, osmolality and vase life of cut flowers were observed. Flowers treated with cold and dry storage had higher moisture content compared to control sample. However, this trend was evident only for 3-day cold and dry stored sample during the whole storage period. The fresh weight of cut flowers increased gradually when the samples were transferred to ambient temperature in water bottles and then declined steadily before reaching the peak in between 6-8 days of vase life. However, the changes of fresh weight of control sample were substantially faster than samples pre-treated with cold and dry storage. This was also correlated with the water balance of cut flower as it reached the minus (-) value in 6-8 days of vase life at ambient temperature. Cut lily flowers showed high osmolality values corresponding with the duration of dry storage regardless of low or higher temperature. However, osmolality had no effect on vase life since flower stem absorbed water rapidly at the end of dry storage period. Our vase life results suggest that cold and dry storage of lily cut flowers for a certain period could ensure longer vase life at ambient temperature. It was observed that prolonging the storage period at cold and dry condition for more than a week significantly increased bud abortion, reduced longevity of flowers and reduced the vase life of cut flowers. On the other hand, the shorter cold and dry storage treatment delayed the bud opening and senescence of the flowers, thus, slowering the normal maturation and aging. Results indicated that dry and cold storage at $5^{\circ}C$ for 3 days was effective in maintaining and preserving overall quality and vase life at ambient condition of oriental hybrid lily cut flowers.

Radiation Exposure Dose on Persons Engaged in Radiation-related Industries in Korea (한국에서 방사선 관련 종사자들의 개인피폭선량 실태에 관한 연구)

  • Lim, Bong-Sik
    • Journal of radiological science and technology
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    • v.29 no.3
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    • pp.185-195
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    • 2006
  • Purpose: This study investigated the status of radiation exposure doses since the establishment of the "Regulations on Safety Management of Diagnostic Radiation Generation Device" in January 6, 1995. Method: The level of radiation exposure in people engaged or having been engaged in radiation-related industries of inspection organizations, educational organizations, military units, hospitals, public health centers, businesses, research organizations or clinics over a 5 year period from Jan. 1, 2000 to Dec. 31, 2004 was measured. The 149,205 measurement data of 57,136 workers registered in a measurement organization were analysed in this study. Frequency analysis, a Chi-square test, Chi-square trend test, and ANOVA was used for data analysis. Results: Among 57,136, men were 40,870(71.5%). 50.3% of them were radiologic technologists, otherwise medical doctors(22.7%), nurse(2.9%) and others(24.1%). The average of depth radiation and surface radiation during the 5-year period were found to decrease each year. Both the depth radiation and surface radiation exposure were significantly higher in males, in older age groups, in radiological technologists of occupation. The departments of nuclear medicine had the highest exposure of both depth and surface radiation of the divisions of labor. There were 1.98 and 2.57 per 1,000 person-year were exposed more than 20 mSv(limit recommended by International Commission on Radiological Protection) in depth and surface radiation consequently. Conclusion: The total exposure per worker was siginifcantly decreased by year. But Careful awareness is needed for the workers who exposed over 20 mSv per year. In order to minimize exposure to radiation, each person engaged in a radiation-related industry must adhere to the individual safety management guidelines more thoroughly. In addition, systematic education and continuous guidance aimed at increasing the awareness of safety must be provided.

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Research of z-axis geometric dose efficiency in multi-detector computed tomography (MDCT 장치의 z-축 기하학적 선량효율에 관한 연구)

  • Kim, You-Hyun;Kim, Moon-Chan
    • Journal of radiological science and technology
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    • v.29 no.3
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    • pp.167-175
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    • 2006
  • With the recent prevalence of helical CT and multi-slice CT, which deliver higher radiation dose than conventional CT due to overbeaming effect in X-ray exposure and interpolation technique in image reconstruction. Although multi-detector and helical CT scanner provide a variety of opportunities for patient dose reduction, the potential risk for high radiation levels in CT examination can't be overemphasized in spite of acquiring more diagnostic information. So much more concerns is necessary about dose characteristics of CT scanner, especially dose efficient design as well as dose modulation software, because dose efficiency built into the scanner's design is probably the most important aspect of successful low dose clinical performance. This study was conducted to evaluate z-axis geometric dose efficiency in single detector CT and each level multi-detector CT, as well as to compare z-axis dose efficiency with change of technical scan parameters such as focal spot size of tube, beam collimation, detector combination, scan mode, pitch size, slice width and interval. The results obtained were as follows ; 1. SDCT was most highest and 4 MDCT was most lowest in z-axis geometric dose efficiency among SDCT, 4, 8, 16, 64 slice MDCT made by GE manufacture. 2. Small focal spot was 0.67-13.62% higher than large focal spot in z-axis geometric dose efficiency at MDCT. 3. Large beam collimation was 3.13-51.52% higher than small beam collimation in z-axis geometric dose efficiency at MDCT. 4. Z-axis geometric dose efficiency was same at 4 slice MDCT in all condition and 8 slice MDCT of large beam collimation with change of detector combination, but was changed irregularly at 8 slice MDCT of small beam collimation and 16 slice MDCT in all condition with change of detector combination. 5. There was no significant difference for z-axis geometric dose efficiency between conventional scan and helical scan, and with change of pitch factor, as well as change of slice width or interval for image reconstruction. As a conclusion, for reduction of patient radiation dose delivered from CT examination we are particularly concerned with dose efficiency of equipment and have to select proper scanning parameters which increase z-axis geometric dose efficiency within the range of preserving optimum clinical information in MDCT examination.

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A Study of the Improvement of Clinical and Practical Trainings in the Education of Radiologic Technologists (방사선사(放射線士) 교육(敎育)의 임상실습(臨床實習) 개선(改善)에 관(關)한 연구(硏究))

  • Lee, Man-Koo;Kang, Se-Sik;Yoon, Han-Sik;Huh, Joon
    • Journal of radiological science and technology
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    • v.6 no.1
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    • pp.117-129
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    • 1983
  • This study, in order to improve clinical and practical trainings in the education of radiologic technologists, applies to 76 medical institutions of 91 ones which are used as the hospitals of clinical and practical training in 9 existing junior colleges except 3 new ones of 12 ones throughout all over the country from November 1, in 1982 to April 30, in 1983. And the purpose of this study is to research the percent conditions of basic practical trainings and clinical ones enforced in each college, and the percent conditions, equipments, contents, and opinions in clinical and practical trainings enforced in each hospital. The results are summarized as follows; 1. In the case of junior colleges in the whole country the curriculum of basic practical trainings averages 336.66 hours and the limits are between 120 and 510 hours. The actual hours in practice average 140 hours and the limits are between 60 and 240 hours, which correspond to 41.58% of the curriculum of basic practical trainings. 2. There were three junior colleges among nine that had a reserved hospital for clinical and practical trainings(only 33.33%). 3. The period of the practice was almost vacation in 4 junior colleges. The practice was conducted only for students to want the practice(44.45%), junior colleges that all students in them conducted the practice was 2 junior colleges and presented 22.22%. 4. In the field of students engaging in the practice, each field of radiation therapy and nuclear medicine presented 16.5%, 20.3% and almost students didin't have experience for the practice. 5. In medical institutions the educational institutions for intern showed 67.11%. Hospital with radiologist showed 26.32%. Radiotechnologist who had experience below 5 years presented 60.17%. 6. In the equipment for radiation diagnosis, each hospital had no difference. The number of hospitals passessing diagnostic equipments above 125 KVP was 56.26%. But radiation therapy equipment and nuclear medicine equipment had extremely low rate. 7. In the diagnosis of patient in the practice hospital, conventional radiography-to Skull, Chest, Abdomen, Skeleton, Urogenital system-reached the criterion. But special radiography was comparatively low. There appeared low rate, 32.89% in the field of nuclear medicine, 15.79% in the field of radiation therapy. 8. Students who carried out the practice were 1-89 students, days in practice were 1-30 days. There were differences in that point among among hospitals. Junior colleges conducting the practice were 2 colleges per hospital. Scope of the object were 1-8 junior colleges. 9. The practice conducted for the request of the colleges presented 72.37%, in addition, The prctices were conducted for growth of the younger generation and the same coperation with the colleges establishment of sisterhood with the colleges, relationship with students. 10. The practice conducted without the establishment of plan presented 59.21% The need for guiding book to the practice and evaluating was recognized over 90%. 11. In the relation between the practice with achievement of credit. There were big differences in opinion between hospitals-Group and the colleges-Group; hospital-Group had opinion that must follow achievement of credit with the practice. The colleges-Group had opinion that must conduct the practice after achieving credit. 12. After conducting the practice, in the practice leaders satisfaction degree dissatisfactory opinion presented the most rate 80.26%. Very much satisfactory opinion, as one hospital, presentd only 1.32%. 13. Both hospitals-Group and the colleges-Group had an opinion that the practice leader must have actual experiences, lectures and achievement, an opinion that actual experiences is over 5 years. 14. In the guide of human relation, cooperation, responsibility, courtesy to patients. Both hospitals-Group and the colleges-Group had an opinion that the guide must be involved in the period of the practice and must be instructed.

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A Study of Technical Approach Methods to Transabdominal Ultrasonography of the Extrahepatic Bile Ducts and of Following Effects from the Scan Training (간외담관 초음파검사의 주사방법 개선과 교육 후 주사 습득효과에 관한 연구)

  • Lee, In-Ja;Kang, Dae-Hyun;Kim, Bo-Young
    • Journal of radiological science and technology
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    • v.31 no.2
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    • pp.149-159
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    • 2008
  • The purposes of this study are to analyze abnormal dilatation of the extrahepatic bile ducts by using transabdominal ultrasound, to confirm the existence of bile ducts diseases and their interrelationship, and for it to give a new theoretical basis for the technical access to extrahepatic bile ducts, upon which to analyze the ripple effects of the scan training. After teaching technical access process based on the new theory about extrahepatic bile duct to the thirty students who are studying ultrasonography, we allocated three hours per one student (30 mins ${\times}$ 6 times) to focus on the training of scanning skill. Training has been performed by one-to-one method. For evaluation, all the students have to perform the scans on (1) confluence of the right and left hepatic ducts (extrahepatic bile ducts and cystic duct), (2) the suprapancreatic bile duct, (3) the intrapancreatic bile duct, (4) intrapapilla Duct, based on the clearly divided concept. The existing training and methods have had low confidency about transabdominal ultrasonography of the extrahepatic bile duct and had limitation with which they could image only the suprapancreatic bile duct. The evaluation after finishing the train based on the new theory, however, all the students (30students) can access to (1) confluence of the right and left hepatic ducts(extrahepatic bile ducts and cystic duct), (2) the suprapancreatic bile duct objectively. 24 students can access to (3) the intrapancreatic bile duct and only one student can even make an image for (4) the intrapapilla Duct Though the evaluation on extrahepatic bile duct has to be performed with multi-sided method considering intrahepatic cause, bile duct cause and pathophysiological cause, only if we can image the extrahepatic bile duct to ampular of Vater objectively and confidently, we can greatly reduce invasive procedure such as ERCP, which is for the purpose of simple differential diagnosis and painful to the patients. Therefore if we concentrate on the scanning train based on the new theory to raise the confidency about ultrasonography, the effect will be doubled.

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A Study of Factors Affecting Measurement of Kidney Size in Ultrasonography (초음파로 신장의 크기 측정 시 미치는 영향에 관한 연구)

  • Yoon, Seok-Hwan;Kim, Yun-Min;Choi, Jun-Gu
    • Journal of radiological science and technology
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    • v.31 no.2
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    • pp.161-169
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    • 2008
  • Since measuring the size of kidney with sonography becomes an important index for diagnosis, treatment, and prognostic prediction in kidney disease, the accurate measurement and evaluation on this are clinically very important. Accordingly, the purpose of this study was to increase reproducibility and objectivity in measuring the size of kidney by enumerating factors that have an impact for measurement. It targeted 44 adults in Korea at the age of 21-27. It measured in order for both kidneys to be seen most largely while changing a subject-examiner's position in a state of fasting for 8 hours and a transducer's approaching direction. It compared a size of kidney by measuring, respectively, with the same method in 30 minutes and in 1 hour after drinking water in 700-1,000cc. In case of the lateral approach scan in decubitus position, the average length of the kidney both to the right and the left and the deviation of measurement to be the largest. In NPO(None Per Oral) state, the average length in the right kidney was 10.19cm, and the average length in the left kidney was 10.33cm. In 60 minutes after taking moisture, the average length in the right kidney was 10.94cm, and the average length in the left kidney was 11.13cm. In comparing the average length of the kidney in NPO state and its average length in 60 minutes after taking moisture, the size swelled by 7.3% for the length in the right kidney and by 7.7% in the left, thereby having been indicated to be statistically significant(P<0.003). The measurement in a size of kidney by using ultrasound may be measured differently depending on a patient's state of taking moisture and a transducer's approaching direction. It is thought that when the measurement in a size of kidney is especially important clinically, the intake and intake time in moisture need to be considered and that measuring with the posterior approach in prone position is a good method aiming to increase reproducibility in measuring length of the kidney.

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A Study on Retrieval of Storage Heat Flux in Urban Area (우리나라 도심지에서의 저장열 산출에 관한 연구)

  • Lee, Darae;Kim, Honghee;Lee, Sang-Hyun;Lee, Doo-Il;Hong, Jinkyu;Hong, Je-Woo;Lee, Keunmin;Lee, Kyeong-sang;Seo, Minji;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.34 no.2_1
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    • pp.301-306
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    • 2018
  • Urbanization causes urban floods and urban heat island in the summer, so it is necessary to understanding the changes of the thermal environment through urban climate and energy balance. This can be explained by the energy balance, but in urban areas, unlike the typical energy balance, the storage heat flux saved in the building or artificial land cover should be considered. Since the environment of each city is different, there is a difficulty in applying the method of retrieving the storage heat flux of the previous research. Especially, most of the previous studies are focused on the overseas cities, so it is necessary to study the storage heat retrieval suitable for various land cover and building characteristics of the urban areas in Korea. Therefore, the object of this study, it is to derive the regression formula which can quantitatively retrieve the storage heat using the data of the area where various surface types exist. To this end, nonlinear regression analysis was performed using net radiation and surface temperature data as independent variables and flux tower based storage heat estimates as dependent variables. The retrieved regression coefficients were applied to each independent variable to derive the storage heat retrieval regression formula. As a result of time series analysis with flux tower based storage heat estimates, it was well simulated high peak at day time and the value at night. Moreover storage heat retrieved in this study was possible continuous retrieval than flux tower based storage heat estimates. As a result of scatter plot analysis, accuracy of retrieved storage heat was found to be significant at $50.14Wm^{-2}$ and bias $-0.94Wm^{-2}$.

An Adjustment of Cloud Factors for Continuity and Consistency of Insolation Estimations between GOES-9 and MTSAT-1R (GOES-9과 MTSAT-1R 위성 간의 일사량 산출의 연속성과 일관성 확보를 위한 구름 감쇠 계수의 조정)

  • Kim, In-Hwan;Han, Kyung-Soo;Yeom, Jong-Min
    • Korean Journal of Remote Sensing
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    • v.28 no.1
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    • pp.69-77
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    • 2012
  • Surface insolation is one of the major indicators for climate research over the Earth system. For the climate research, long-term data and wide range of spatial coverage from the data observed by two or more of satellites of the same orbit are needed. It is important to improve the continuity and consistency of the derived products, such as surface insolation, from different satellites. In this study, surface insolations based on Geostationary Operational Environmental Satellite (GOES-9) and Multi-functional Transport Satellites (MTSAT-1R) were compared during overlap period using physical model of insolation to find ways to improve the consistency and continuity between two satellites through comparison of each channel data and ground observation data. The thermal infrared brightness temperature of two satellites show a relatively good agreement between two satellites : rootmean square error (RMSE)=5.595 Kelvin; Bias=2.065 Kelvin. Whereas, visible channels shown a quite different values, but it distributed similar tendency. And the surface insolations from two satellites are different from the ground observation data. To improve the quality of retrieved insolations, we have reproduced surface insolation of each satellite through adjustment of the Cloud Factor, and the Cloud Factor for GOES-9 satellite is modified based on the analysis result of difference channel data. As a result, the insolations estimated from GOES-9 for cloudy conditions show good agreement with MTSAT-1R and ground observation : RMSE=$83.439W\;m^{-2}$ Bias=$27.296W\;m^{-2}$. The result improved accuracy confirms that the modification of Cloud Factor for GOES-9 can improve the continuity and consistency of the insolations derived from two or more satellites.

Accuracy Evaluation of Daily-gridded ASCAT Satellite Data Around the Korean Peninsula (한반도 주변 해역에서의 ASCAT 해상풍 격자 자료의 정확성 평가)

  • Park, Jinku;Kim, Dae-Won;Jo, Young-Heon;Kim, Deoksu
    • Korean Journal of Remote Sensing
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    • v.34 no.2_1
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    • pp.213-225
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    • 2018
  • In order to access the accuracy of the gridded daily Advanced Scatterometer (hereafter DASCAT) ocean surface wind data in the surrounding of Korea, the DASCAT was compared with the wind data from buoys. In addition, the reanalysis data for wind at 10 m provided by European Centre for Medium-Range Weather Forecasts (ECMWF, hereafter ECMWF), National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR, hereafter NCEP), Modern Era Retrospective-analysis for Research and Applications-2 (MERRA-2, hereafter MERRA) were compared and analyzed. As a result, the RMSE of DASCAT for the actual wind speed is about 3 m/s. The zonal components of wind of buoys and the DASCAT have strong correlation more than 0.8 and the meridional components of wind them have lower correlation than that of zonal wind and are the lowest in the Yellow Sea (r=0.7). When the actual wind speed is below 10 m/s, the EMCWF has the highest accuracy, followed by DASCAT, MERRA, and NCEP. However, under the wind speed more than 10 m/s, DASCAT shows the highest accuracy. In the nature of error according to the wind direction, when the zonal wind is strong, all dataset has the error of more than $70^{\circ}$ on the average. On the other hand, the RMSE of wind direction was recorded $50^{\circ}$ under the strong meridional winds. ECMWF shows the highest accuracy in these results. The RMSE of the wind speed according to the wind direction varied depending on the actual wind direction. Especially, MERRA has the highest RMSE under the westerly and southerly wind condition, while the NCEP has the highest RMSE under the easterly and northerly wind condition.

Empirical Estimation and Diurnal Patterns of Surface PM2.5 Concentration in Seoul Using GOCI AOD (GOCI AOD를 이용한 서울 지역 지상 PM2.5 농도의 경험적 추정 및 일 변동성 분석)

  • Kim, Sang-Min;Yoon, Jongmin;Moon, Kyung-Jung;Kim, Deok-Rae;Koo, Ja-Ho;Choi, Myungje;Kim, Kwang Nyun;Lee, Yun Gon
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.451-463
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    • 2018
  • The empirical/statistical models to estimate the ground Particulate Matter ($PM_{2.5}$) concentration from Geostationary Ocean Color Imager (GOCI) Aerosol Optical Depth (AOD) product were developed and analyzed for the period of 2015 in Seoul, South Korea. In the model construction of AOD-$PM_{2.5}$, two vertical correction methods using the planetary boundary layer height and the vertical ratio of aerosol, and humidity correction method using the hygroscopic growth factor were applied to respective models. The vertical correction for AOD and humidity correction for $PM_{2.5}$ concentration played an important role in improving accuracy of overall estimation. The multiple linear regression (MLR) models with additional meteorological factors (wind speed, visibility, and air temperature) affecting AOD and $PM_{2.5}$ relationships were constructed for the whole year and each season. As a result, determination coefficients of MLR models were significantly increased, compared to those of empirical models. In this study, we analyzed the seasonal, monthly and diurnal characteristics of AOD-$PM_{2.5}$model. when the MLR model is seasonally constructed, underestimation tendency in high $PM_{2.5}$ cases for the whole year were improved. The monthly and diurnal patterns of observed $PM_{2.5}$ and estimated $PM_{2.5}$ were similar. The results of this study, which estimates surface $PM_{2.5}$ concentration using geostationary satellite AOD, are expected to be applicable to the future GK-2A and GK-2B.