• Title/Summary/Keyword: variability measure

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Generation of Land Surface Temperature Orthophoto and Temperature Accuracy Analysis by Land Covers Based on Thermal Infrared Sensor Mounted on Unmanned Aerial Vehicle (무인항공기에 탑재된 열적외선 센서 기반의 지표면 온도 정사영상 제작 및 피복별 온도 정확도 분석)

  • Park, Jin Hwan;Lee, Ki Rim;Lee, Won Hee;Han, You Kyung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.4
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    • pp.263-270
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    • 2018
  • Land surface temperature is known to be an important factor in understanding the interactions of the ground-atmosphere. However, because of the large spatio-temporal variability, regular observation is rarely made. The existing land surface temperature is observed using satellite images, but due to the nature of satellite, it has the limit of long revisit period and low accuracy. In this study, in order to confirm the possibility of replacing land surface temperature observation using satellite imagery, images acquired by TIR (Thermal Infrared) sensor mounted on UAV (Unmanned Aerial Vehicle) are used. The acquired images were transformed from JPEG (Joint Photographic Experts Group) to TIFF (Tagged Image File Format) format and orthophoto was then generated. The DN (Digital Number) value of orthophoto was used to calculate the actual land surface temperature. In order to evaluate the accuracy of the calculated land surface temperature, the land surface temperature was compared with the land surface temperature directly observed with an infrared thermometer at the same time. When comparing the observed land surface temperatures in two ways, the accuracy of all the land covers was below the measure accuracy of the TIR sensor. Therefore, the possibility of replacing the satellite image, which is a conventional land surface temperature observation method, is confirmed by using the TIR sensor mounted on UAV.

The classification and comparison of genetic diversity of genus Malus using RAPD (RAPD를 이용한 능금속 식물종의 계통관계와 유전적 다양성)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.17 no.6 s.86
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    • pp.756-761
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    • 2007
  • Cenus Malus is a long-lived woody species primarily distributed throughout Asia. Many species of this genus are regarded as agriculturally and ecologically important. The phynetics and genetic diversity among eight species of genus Malus were reconstructed using the random amplified polymorphic DNA (RAPD) markers. In a simple measure of intraspecies variability by the percentage of polymorphic bands, the M. micromalus exhibited the lowest variation (34.7%). The M. pumila showed the highest (50.0%). Mean number of alleles per locus (A) ranged from 1.347 to 1.500 with a mean of 1.437. The phenotypic frequency of each band was calculated and used in estimating genetic diversify (H) within species. The mean of H was 0.190 across species, varying from 0.155 to 0.220. In particular, two cultivated species, M. pumila and M. asiatica, had high expected diversity, 0.314 and 0.307, respectively. On a per locus basis, the proportion of total genetic variation due to differences among species ranged from 0.388 to 0.472 with a mean of 0.423, indicating that 42.3% of the total variation was found among species. The phylogenetic tree showed three distinct elates. One includes M. sieversii, M. pumila, and M. asiatica. Another includes three M. baccata taxa. The other includes M. sieboldii, M. floribunsa, and M. micromalus. One variety and one form of M. sieboldii were well separated each other. RAPD markers are useful in germ-plasm classification of genus Malus and evolutionary studies.

Assessment of a rain barrel sharing network in Korea using storage-reliability-yield relationship (저류용량-신뢰도-수요량 관계를 이용한 레인배럴 공유 네트워크의 국내 성능 평가)

  • Kwon, Youjeong;Seo, Yongwon;Park, Chang Kun
    • Journal of Korea Water Resources Association
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    • v.53 no.11
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    • pp.961-971
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    • 2020
  • The Intergovernmental Panel on Climate Change (IPCC) reported that the amount of precipitation in South Korea would increase regardless of the reduction of Greenhouse Gas (GHG) emissions. Moreover, the temporal and spatial rainfall variation would also increase in the future. Due to the geographic allocation of Korea, more than 80% of the annual precipitation occurs in the wet season from early July to late September. It is expected that the average precipitation in this period will increase from the Representative Concentration Pathways (RCP) scenario projections. These predictions imply an increased variability of available water resources. Rainwater harvesting system is widely used as an alternative water resources today. This study introduces a RBSN (rain barrel sharing network) as an efficient way to utilize alternative water resources under the RCP scenarios. The concept of RBSN combines individual rainwater harvesting system to a sharing network, which make the whole system more reliable. This study evaluated a RBSN in South Korea composed of four users based on a storage-reliability-yield (SRY) relationship. The study area comprises all 17 provincal areas in South Korea. The result showed a huge benefit from a RBSN in Korea under the historical rainfall condition. Even in the climate change condition, the results showed that a RBSN is still beneficial but the changes in reliability are different depending on provinces in Korea. The results of this study shows that a RBSN is a very effective and alternative measure that can deal with the impacts of climate change in the near future.

Development of a Photoplethysmographic method using a CMOS image sensor for Smartphone (스마트폰의 CMOS 영상센서를 이용한 광용적맥파 측정방법 개발)

  • Kim, Ho Chul;Jung, Wonsik;Lee, Kwonhee;Nam, Ki Chang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.6
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    • pp.4021-4030
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    • 2015
  • Pulse wave is the physiological responses through the autonomic nervous system such as ECG. It is relatively convenient because it can measure the signal just by applying a sensor on a finger. So, it can be usefully employed in the field of U-Healthcare. The objects of this study are acquiring the PPG (Photoplethysmography) one of the way of measuring the pulse waves in non-invasive way using the CMOS image sensor on a smartphone camera, developing the portable system judging stressful or not, and confirming the applicability in the field of u-Healthcare. PPG was acquired by using image data from smartphone camera without separate sensors and analyzed. Also, with that image signal data, HRV (Heart Rate Variability) and stress index were offered users by just using smartphone without separate host equipment. In addition, the reliability and accuracy of acquired data were improved by developing additional hardware device. From these experiments, we can confirm that measuring heart rate through the PPG, and the stress index for analysis the stress degree using the image of a smartphone camera are possible. In this study, we used a smartphone camera, not commercialized product or standardized sensor, so it has low resolution than those of using commercialized external sensor. However, despite this disadvantage, it can be usefully employed as the u-Healthcare device because it can obtain the promising data by developing additional external device for improvement reliability of result and optimization algorithm.

A Study on Degradation Phenomenon Based on Test Device for Aging Diagnosis in PV Modules (태양광모듈의 열화진단 시험장치 구현 및 열화특성에 관한 연구)

  • Shen, Jian;Lee, Hu-Dong;Tae, Dong-Hyun;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.27-35
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    • 2021
  • Generally, a proper evaluation method of the aging phenomenon of PV modules is required as the electrical performance and lifespan of PV modules can degrade significantly due to several environmental factors, while they are generally known as devices that are used semi-permanently for more than 20 years. On the other hand, there is a lack of objectivity in the existing evaluation method of the aging phenomenon, which compares the adjusted PV output based on STC with the initial PV module specifications due to the data distortion while adjusting the measured data. Therefore, this study implemented a test device for an aging diagnosis to measure and collect actual data from a PV module section and modeled the data for aging using MATLAB S/W to minimize the variability of the PV output, communication error, and delay. Furthermore, this study confirmed the usefulness of the presented test device for aging diagnosis of the PV modules by diagnosing the total period and yearly-basis degradation rate of aging PV modules as 25.73% and 1.55%, respectively, according to the on-site output characteristics of the PV modules by season.

Safety and efficacy of target controlled infusion administration of propofol and remifentanil for moderate sedation in non-hospital dental practice

  • Douglas Lobb;Masoud MiriMoghaddam;Don Macalister;David Chrisp;Graham Shaw;Hollis Lai
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.23 no.1
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    • pp.19-28
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    • 2023
  • Background: Fearful and anxious patients who find dental treatment intolerable without sedative and analgesic support may benefit from moderate sedation. Target controlled infusion (TCI) pumps are superior to bolus injection in maintaining low plasma and effect-site concentration variability, resulting in stable, steady-state drug concentrations. We evaluated the safety and efficacy of moderate sedation with remifentanil and propofol using TCI pumps in non-hospital dental settings. Methods: A prospective chart review was conducted on 101 patients sedated with propofol and remifentanil using TCI pumps. The charts were completed at two oral surgeons and one general dentist's office over 6 months. Hypoxia, hypotension, bradycardia, and over-sedation were considered adverse events and were collected using Tracking and Reporting Outcomes of Procedural Sedation (TROOPS). Furthermore, patient recovery time, sedation length, drug dose, and patient satisfaction questionnaires were used to measure sedation effectiveness. Results: Of the 101 reviewed sedation charts, 54 were of men, and 47 were of women. The mean age of the patients was 40.5 ±18.7 years, and their mean BMI was 25.6 ± 4.4. The patients did not experience hypoxia, bradycardia, and hypotension during the 4694 min of sedation. The average minimum Mean Arterial Pressure (MAP) and heartbeats were 75.1 mmHg and 60.4 bpm, respectively. 98% of patients agreed that the sedation technique met their needs in reducing their anxiety, and 99% agreed that they were satisfied with the sedation 24 hours later. The average sedation time was 46.9 ± 55.6 min, and the average recovery time was 12.4 ± 4.4 min. Remifentanil and propofol had mean initial effect-site concentration doses of 0.96 µ/.ml and 1.0 ng/ml respectively. The overall total amount of drug administered was significantly higher in longer sedation procedures compared to shorter ones, while the infusion rate decreased as the procedural stimulus decreased. Conclusion: According to the results of this study, no patients experienced adverse events during sedation, and all patients were kept at a moderate sedation level for a wide range of sedation times and differing procedures. The results showed that TCI pumps are safe and effective for administering propofol and remifentanil for moderate sedation in dentistry.

Measurements of Trimethylamine (TMA) in air by Tedlar bag sampling and SPME analysis (환경대기 중 Trimethylamine (TMA)의 측정: Tedlar bag 방식의 채취와 SPME 분석법의 특성 연구)

  • Kim, K.H.;Hyum, S.H.;Im, M.S.
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.96-102
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    • 2006
  • Trimethylamine (TMA) is one of the difficult odorous compounds for the collection and analysis. Although sulfuric acid absorption and/or sulfuric acid impregnated filter method are commonly recommended for its sampling, these methods also suffer from difficulties involved in sample treatment and operational procedures. Hence, as an ancillary approach to measure TMA, we investigated the combination of bag sampling and SPME analysis for TMA measurements. For the purpose of our study, we investigated the following three subjects: 1) temporal variability of standard storage, 2) bag loss effect of TMS, and 3) TMA loss due to repetitive analysis of an identical bag sample. According to our storage test up to 7 or 20 dyas, TMA loss were found to occur up to 40 to 50% within relatively short period of up to 48 hrs depending on its concentration ranges. When the tests were made for bag loss by transferring TMA standards across different size bags, we were able to find that the extent of bag loss are not significant with 5 to 20% loss rate. Finally, the TMA sorptive loss via its exposure to SPME fiber was generally estimated to run from 2 to 3%.

Interpretation of Complete Tumor Response on MRI Following Chemoradiotherapy of Rectal Cancer: Inter-Reader Agreement and Associated Factors in Multi-Center Clinical Practice

  • Hae Young Kim;Seung Hyun Cho;Jong Keon Jang;Bohyun Kim;Chul-min Lee;Joon Seok Lim;Sung Kyoung Moon;Soon Nam Oh;Nieun Seo;Seong Ho Park
    • Korean Journal of Radiology
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    • v.25 no.4
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    • pp.351-362
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    • 2024
  • Objective: To measure inter-reader agreement and identify associated factors in interpreting complete response (CR) on magnetic resonance imaging (MRI) following chemoradiotherapy (CRT) for rectal cancer. Materials and Methods: This retrospective study involved 10 readers from seven hospitals with experience of 80-10210 cases, and 149 patients who underwent surgery after CRT for rectal cancer. Using MRI-based tumor regression grading (mrTRG) and methods employed in daily practice, the readers independently assessed mrTRG, CR on T2-weighted images (T2WI) denoted as mrCRT2W, and CR on all images including diffusion-weighted images (DWI) denoted as mrCRoverall. The readers described their interpretation patterns and how they utilized DWI. Inter-reader agreement was measured using multi-rater kappa, and associated factors were analyzed using multivariable regression. Correlation between sensitivity and specificity of each reader was analyzed using Spearman coefficient. Results: The mrCRT2W and mrCRoverall rates varied widely among the readers, ranging 18.8%-40.3% and 18.1%-34.9%, respectively. Nine readers used DWI as a supplement sequence, which modified interpretations on T2WI in 2.7% of cases (36/1341 [149 patients × 9 readers]) and mostly (33/36) changed mrCRT2W to non-mrCRoverall. The kappa values for mrTRG, mrCRT2W, and mrCRoverall were 0.56 (95% confidence interval: 0.49, 0.62), 0.55 (0.52, 0.57), and 0.54 (0.51, 0.57), respectively. No use of rectal gel, larger initial tumor size, and higher initial cT stage exhibited significant association with a higher interreader agreement for assessing mrCRoverall (P ≤ 0.042). Strong negative correlations were observed between the sensitivity and specificity of individual readers (coefficient, -0.718 to -0.963; P ≤ 0.019). Conclusion: Inter-reader agreement was moderate for assessing CR on post-CRT MRI. Readers' varying standards on MRI interpretation (i.e., threshold effect), along with the use of rectal gel, initial tumor size, and initial cT stage, were significant factors associated with inter-reader agreement.

Characteristics of Radon Variability in Soils at Busan Area (부산광역시 일대의 토양 내 라돈 농도 변화 특성)

  • Kim, Jin-Seop;Kim, Sun-Woong;Lee, Hyo-Min;Choi, Jeong-Yun;Moon, Ki-Hoon
    • Economic and Environmental Geology
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    • v.45 no.3
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    • pp.277-294
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    • 2012
  • The characteristics of temporal spacial radon variation in soil according to parent rock type and affecting factors were studied in Busan, Korea. The concentration of $^{222}Rn$ in soils and their parent elements ($^{226}Ra$,$^{228}Ra$, U and Th) in rocks and soils were measured at 24 sites in Busan area. The distribution and transportation behavior of these parent elements were analyzed and their correlations to radon concentration in soil were determined. Topographic effects were also evaluated. Two in-situ radon measurement (soil probe and buried tube) methods were applied to measure radon concentration in soil and their accuracies were evaluated. The spatial variation of radon in soil generally reflected U concentration in the parent rock. Average radon concentrations were higher in plutonic rocks than in volcanic rocks and were decreased in the order of felsic>intermediate>mafic rock. However, the radon concentrations were significantly varied in soils developed from same parent rocks due to the disequilibrium of U and $^{226}Ra$ between rock and soil. As results, the correlation of these element concentrations between rocks and soils was very low and radon concentrations in soils had highly co-related to the concentrations of these elements in soils. Th and $^{228}Ra$ show complex enrichment characteristics, differing significantly with U, in soils developed from same parent rock because the geochemical behavior of these elements during weathering and soil developing process was different with U. The radon concentrations in the same depth of soil in slope area were also different according to positions. The radon concentrations in soils developed from same parent rocks (19 sites at Pusan National University) varied 6.8~29.8Bq/L range because of small scale topographic variation. The opposite seasonal variation pattern of radon were observed according to soil properties. It was determined that buried tube method is more accurate method than soil probe method and was very advantageous application for the analysis for the characteristics of temporal spacial radon variation in soil.

AGE AT MARRIAGE AND FERTILITY OF WOMEN IN THREE SELECTED AREAS IN KOREA, 1970 (한국 3개 지역의 결혼, 결혼년령 및 출산력에 관한 연구)

  • 김모임
    • Journal of Korean Academy of Nursing
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    • v.3 no.3
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    • pp.1-14
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    • 1973
  • This study is designed to meet the following objectives: (1) To study attitude and behavior regarding marriage and age at marriage, (2) To learn correlates of age at marriage and to examine their relations, (3) To measure relative importance of the correlates of age at marriage, and (4) To study relations of age at marriage and family planning practice to fertility and their relative importance as correlates of fertility. The data are obtained by an independent cross-sectional survey in three study areas purposively selected to represent metropolitan. semihuman. rural population. The study population is confined to women age 17-50 as of survey. The overall response rate is 90%. Reliability of data is measured by . individual and aggregate inconsistency based upon a 15% subsample of the original interviews. The individual inconsistency (31%) is found to be high compared to the aggregate inconsistency (6%) for all 85 variables. However, the magnitude of differences between means is small, and the mean absolute shifts and proportional shifts are also small on the whole. In a word respondents did not change their answers too extremely or radically. The study populations of each study area are compared on some basic characteristics. It is found that the three study populations have more dissimilarities than similarities. The findings on seven different attitudinal positions of women toward marriage indicate that there have been tremendous changes in all study areas Iron "traditional" attitudes which have been prevalent for a long time in Korean society to "liberalized" or "modernized" attitudes. An apparent tendency is that women generally take a position of a "golden mean" attitude by not preferring either extreme of marriage attitudes. Nevertheless, the young, single, educated, and urbanite appears more "liberalized. " There has been some increase in ideal age at marriage from 1958 to 1970 for both sexes. No age group, marital status, or study area differentials in ideal age at marriage are found, the average ideal age at marriage in every sub-group being 24-25. Awareness of existing legal marriageable ages is low; only 4.4% are aware that "with parental permission: minimum age for males is 18 years and for females 16 years,"and only 3.7% are aware that "without parental permission: 27 years for males and 23 years for females." People in Korra tend to marry spouses who are in various social ways like themselves: the similarities include (a) education, occupational status of father, (c) economic status, (d) usual residence before marriage, and (e) religion. Both singulars and actual mean ages at marriage in this study confirm the trend of rising age at marriage previously established by other independent studies. The urban-rural differential in age at marriage is observed, but the differential narrows down gradually from 1935 to 1970. All socio-economic, demographic, and other variables pertaining to wife before and at first marriage, excluding (a) religion, (b) father′s of occupation, and (c) as: of menarche, are correlated with respondent's age at first marriage, whereas only three variables out of all socio-economic variables relating to husband before and at wife′s first marriage, viz., (a) education, (b) usual residence, and (c) economic level of his old home, are correlated with respondent′s age at marriage. Among socio-economic and modernity variables related to either husband or wife at the time of survey, only education and duration of residence are correlated with wife′s age at first marriage. Among the correlates of respondent′age at first marriage, education is in general the most important variable. However, it is found that wife′s education is more important than husband′s. The combined effects or the correlates studied explain no more than about 40% of variance for any of the selected groups of variables. Points which might counteract the effects of late marriage on fertility are not serious in Korea. For each of the correlates of the three fertility indices chosen for this study. namely, (a) number of living children, (b) number of live births, and (c) number of pregnancies, age at marriage is the major contributor to the variance in all age groups except the age group of 20-29 in which the index of family planning practice is the major contributor. The proportion of variability in fertility indices accounted for by the correlates is never more than 40% of the total variance in any age group. Based upon the findings from this study, it could be concluded that in the foreseeable future (a) celibate group will no! be increased to a point that would slow down population growth rate in Korea, (b) age at marriage will not increase continually, (c) although education stands out as the major contributing variable which independently explains the variation in age at marriage, it seems probable that education may not be the major variable in the near future, and (d) despite the fact found by this study that age at marriages has been the major contributor to the variance of each of the fertility indices used, family planning practice will play a more important role in the reduction of fertility in the Korean society. Therefore, factors interrupting practice of family planning must be eliminated and family planning program should be strengthened if further fertility reduction is needed.

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