• Title/Summary/Keyword: 독립표본 T-검정

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Comparison of Three Kinds of Methods on Estimation of Forest Carbon Stocks Distribution Using National Forest Inventory DB and Forest Type Map (국가산림자원조사 DB와 임상도를 이용한 산림탄소저장량 공간분포 추정방법 비교)

  • Kim, Kyoung-Min;Roh, Young-Hee;Kim, Eun-Sook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.69-85
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    • 2014
  • Carbon stocks of NFI plots can be accurately estimated using field survey information. However, an accurate estimation of carbon stocks in other unsurveyed sites is very difficult. In order to fill this gap, various spatial information can be used as an ancillary data. In South Korea, there is the 1:5,000 forest type map that was produced by digital air-photo interpretation and field survey. Because this map contains very detailed forest information, it can be used as the high-quality spatial data for estimating carbon stocks. In this study, we compared three upscaling methods based on the 1:5,000 forest type map and 5th national forest inventory data. Map algebra(method 1), RK(Regression Kriging)(method 2), and GWR(Geographically Weighted Regression)(method 3) were applied to estimate forest carbon stock in Chungcheong-nam Do and Daejeon metropolitan city. The range of carbon stocks from method 2(1.39~138.80 tonC/ha) and method 3(1.28~149.98 tonC/ha) were more similar to that of previous method(1.56~156.40 tonC/ha) than that of method 1(0.00~93.37 tonC/ha). This result shows that RK and GWR considering spatial autocorrelation can show spatial heterogeneity of carbon stocks. We carried out paired t-test for carbon stock data using 186 sample points to assess estimation accuracy. As a result, the average carbon stocks of method 2 and field survey method were not significantly different at p=0.05 using paired t-test. And the result of method 2 showed the lowest RMSE. Therefore regression kriging method is useful to consider spatial variations of carbon stocks distribution in rugged terrain and complex forest stand.

Comparison of Forest Carbon Stocks Estimation Methods Using Forest Type Map and Landsat TM Satellite Imagery (임상도와 Landsat TM 위성영상을 이용한 산림탄소저장량 추정 방법 비교 연구)

  • Kim, Kyoung-Min;Lee, Jung-Bin;Jung, Jaehoon
    • Korean Journal of Remote Sensing
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    • v.31 no.5
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    • pp.449-459
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    • 2015
  • The conventional National Forest Inventory(NFI)-based forest carbon stock estimation method is suitable for national-scale estimation, but is not for regional-scale estimation due to the lack of NFI plots. In this study, for the purpose of regional-scale carbon stock estimation, we created grid-based forest carbon stock maps using spatial ancillary data and two types of up-scaling methods. Chungnam province was chosen to represent the study area and for which the $5^{th}$ NFI (2006~2009) data was collected. The first method (method 1) selects forest type map as ancillary data and uses regression model for forest carbon stock estimation, whereas the second method (method 2) uses satellite imagery and k-Nearest Neighbor(k-NN) algorithm. Additionally, in order to consider uncertainty effects, the final AGB carbon stock maps were generated by performing 200 iterative processes with Monte Carlo simulation. As a result, compared to the NFI-based estimation(21,136,911 tonC), the total carbon stock was over-estimated by method 1(22,948,151 tonC), but was under-estimated by method 2(19,750,315 tonC). In the paired T-test with 186 independent data, the average carbon stock estimation by the NFI-based method was statistically different from method2(p<0.01), but was not different from method1(p>0.01). In particular, by means of Monte Carlo simulation, it was found that the smoothing effect of k-NN algorithm and mis-registration error between NFI plots and satellite image can lead to large uncertainty in carbon stock estimation. Although method 1 was found suitable for carbon stock estimation of forest stands that feature heterogeneous trees in Korea, satellite-based method is still in demand to provide periodic estimates of un-investigated, large forest area. In these respects, future work will focus on spatial and temporal extent of study area and robust carbon stock estimation with various satellite images and estimation methods.

A Study of Physiological Changes by The Types of Paralysis Model in Activity Daily of Living (마비모델 유형별 일상생활활동 수행 시 생리적 변화 연구)

  • Sim, Kyoung-Bo;Kim, Dong-Hyun;Kim, Hee-Jung;Moon, Jung-In;Kim, Hyoung-Min
    • The Journal of Korean society of community based occupational therapy
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    • v.1 no.2
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    • pp.21-30
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    • 2011
  • The previous studies were prevalent a study of treatment like a environmental modification or compensative approach and intervention which used in today to paralyzed patients. These interventions were related with occupational therapy widely. The purpose of this study is to provide a basic datum for environmental modification, compensative approach, and intervention observing physiological changes which is shown in early paralyze patients. The subjects were 40 students who were 20 female and 20 male in a college. The students were devided into hemiplegic and paraplegic model. The model was designed using a experimental cloths. A instrument to measure body composition was a precision instrument. The results of the study were as follow: First, there was no different homogeneity between activity daily of living of hemiplegic and paraplegic model. Second, there was a significant different body water and basal metabolic rate between before and after activity daily of living of hemiplegic model. Third, there was a significant different body water and basal metabolic rate between before and after activity daily of living of paraplegic model. Forth, there were no significant different physiological change between after activity daily of living of hemiplegic model and paraplegic model. We observed early changes of body composition using a hemiplegic and paraplegic model. We could know it was reduced body water rate and basal metabolic rate in regardless of type of paralysis. Therefore, it is important to know these physiological changes of paralyzed patients and improve body water and basal metabolic rate of the patients.

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Analysis of Factors Affecting the Length of Stay in Children(Aged 0 to 12) with Injuries: Centering Around the Data from the Korea National Hospital Discharge In-Depth Injury Surveys (어린이(0-12세) 손상환자의 재원일수에 미치는 요인분석: 퇴원손상심층자료를 중심으로)

  • Lee Chae Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.137-143
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    • 2023
  • This study was conducted to analyze factors affecting the length of stay in children with injuries by determining relationships between length of stay and characteristics of children(aged 0 to 12) with injuries. 7,804 patients aged 0 to 12 who participated in the Korea Nation Hospital Discharge In-Depth Injury Surveys, got a diagnosis of sequelae of injuries and of other consequences of external causes(S00-T98), and were discharged between 1 January 2016 and 31 December 2020 were investigated. A frequency analysis, independent samples t-test, and ANOVA were performed. Also, to identify factors affecting the length of stay, a regression analysis was performed. The average length of stay for the patients investigated in this study was 5.5 days. The length of stay for school-age children(aged 7 to 12) and children who had either public or private coverage was higher than that for preschoolers(aged 0 to 6) and children who didn't have public or private coverage, respectively. The length of stay for children admitted to a hospital in a rural area(Jeolla-do or Gyeongsang-do) was higher than that for children admitted to a hospital in a metropolitan area and the length of stay for children admitted to a hospital that had 100-299 hospital beds was relatively long. However, children who first visited a hospital for outpatient care stayed relatively short in hospital and children who had been burned or injured in traffic crashes stayed relatively long in hospital. Children who got a secondary diagnosis and had a principal procedure or who died after being discharged were in hospital for a long time. The findings of this study shall be useful, as they identified characteristics related to the length of stay for Korean children with injuries and factors that determine the length of stay for those children by analyzing the national dataset, or more specifically, the data from the Korea National Hospital Discharge In-Depth Injury Surveys. The risk of child injuries can be easily reduced by taking actions to prevent them and providing safety education programs. The present study has provided essential baseline data for the provision of aggressive care for child injuries and the establishment of a range of policies for child injury prevention.

The Analysis of Risk Factors of Pulmonary Tuberculosis Patients Failed in Retreatment (재치료실패 폐결핵 환자의 위험인자 분석)

  • Kim, Hyoung-Soo;Lee, Won-Jin;Kong, Seok-Jun;Shon, Mal-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.6
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    • pp.684-690
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    • 2000
  • Background : The most common cause of treatment failure of pulmonary tuberculosis is early stoppage of treatment or irregular medication. The most important aspect of a retreatment is regular medication provided over a long period. Inadequate treatment may cause drug resistance and prolong the duration of chemotherapy. This study analyzed the risk factors of pulmonary tuberculosis patients, who failed in retreatment, and to use the results as basic data in the management of intractable tuberculosis patients with improving the rate of retreatment success. Methods : We performed a retroactive study of 62 pulmonary tuberculosis patients in retreatment at National Mokpo Tuberculosis Hospital from Jan. 1994 to Dec. 1995. The patients were separated into two groups: group I was retreatment failure and group II was retreatrnent success. For the analysis of risk factors in retreatment failure, we compared the difference between the two groups and tested the confidence limit about results of the results by independent t-test, ${\chi}^2$ test and Fisher's exact test. Results : The treatment failure rate of retreatment patients was 13(21%), and treatment success 49(79%). No significant difference (p>0.05)in age, sex, number of treatment, irregular rate of treatment, extent of the disease & cavitary lesion on the chest X-ray, number of resistance drugs, number of used drugs to medication, number of sensitive bactericidal drugs to medication, rate of sensitive drugs to medication and resisiance to INH & RFP had not significant difference. was found. However, the number of treatment was $2.4{\pm}0.8$ in group I and $1.6{\pm}0.9$ in group II, and had showing a significant difference(p<0.05) between the two groups. Conclusion : The risk factor of retreatment failure was more irregular previous treatment the irregularity of the previous treatment. For reducing the retreatment failure of pulmonary tuberculosis, greater efforts are needed more need to be done to prevent failure of first treatment.

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A Study on The Measurement of Cerebral Cortical Thickness in Patients with Mood Disorders (기분장애 환자의 대뇌 피질 두께 측정에 관한 연구)

  • Do-Hun Kim;Hyo-Young Lee
    • Journal of the Korean Society of Radiology
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    • v.18 no.2
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    • pp.73-81
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    • 2024
  • This study compared the cortical thickness of patients with mood disorders and a control group to assess structural abnormalities. A retrospective study was conducted from September 2020 to August 2022 at the Department of Psychiatry, P Hospital in Yangsan, Gyeongsangnam-do. The study included 44 individuals diagnosed with mood disorders and 59 healthy individuals without any pathological lesions. The 3D-T1 MPRAGE images obtained from magnetic resonance imaging examinations were utilized, and FreeSurfer software was employed to measure cortical thickness. Statistical analysis involved independent samples t-tests to measure the differences in means between the two groups, and Cohen's d test was used to compare the effect sizes of the differences. Furthermore, the correlation between the measured average cortical thickness and Positive and Negative Syndrome Scale scores was analyzed. The research results revealed that patients with mood disorders exhibited decreased cortical thickness compared to the normal control group in both superior frontal regions, both rostral middle frontal regions, both caudal middle frontal regions, both pars opercularis, pars orbitals, pars triangularis regions, both superior temporal regions, both inferior temporal regions, both lateral orbitofrontal regions, both medial orbitofrontal regions, both fusiform regions, both posterior cingulate regions, both isthmus cingulate regions, both superior parietal regions, both inferior parietal regions, both supramarginal regions, left postcentral region, right bank of the superior temporal sulcus region, right middle temporal region, right rostral anterior cingulate region, and right insula region. Among them, regions that showed differences with effect sizes of 0.8 or higher were left fusiform (d=0.82), pars opercularis (d=0.94), superior frontal (d=0.88), right lateral orbitofrontal (d=0.85), and pars orbitalis (d=0.89). Additionally, there was a weak negative correlation between PANSS scores and average cortical thickness in both the left hemisphere (r=-0.234) and right hemisphere (r=-0.230). These findings are expected to be helpful in identifying areas of cortical thickness reduction in patients with mood disorders compared to healthy individuals and understanding the relationship between symptom severity and cortical thickness changes.

Association between Oral Health Related Quality of Life(OHQoL) and Oral Health Outcome in Adults over 50 Years Old (50대 이상 장노년층의 구강건강 관련 삶의 질과 구강 건강 결과의 관련성)

  • Cho, Young-Sik;Lim, Soon-Ryun;Hwang, Hye-Rim
    • Journal of dental hygiene science
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    • v.11 no.4
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    • pp.305-310
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    • 2011
  • The purpose of this study was to investigate association between oral health related quality of life(OHRQoL) and health outcome, such as evaluated oral health state, perceived health state and perceived oral health state. 148 of individuals over 50 years old completed a self-reported questionnaire on Oral Health Impact Profile(OHIP-14) and oral examination was perfomed. 9.5% of respondents reported no problems or discomfort using OHIP-14. The most frequently reported problems were physical pain(69.8%) and psychological discomfort(63.5%). 43.9% of the individuals rated their health and oral health as poor and 54.7% were dissatisfied with their oral health. The study showed association between number of DMFT, missing teeth, perceived health state, perceived oral health state, oral health satisfaction and oral health related quality of life. Perceived heath sate was correlated with oral health related quality of life. But the study showed no association between DMFT, number of missing teeth and oral health related quality of life.

Effect of heat treatment of core fabricated by Ni-Cr alloy on marginal and internal fit (열처리가 Ni-Cr 합금으로 제작된 하부구조물의 변연 및 내면 간격에 미치는 영향)

  • Kim, Jae-Hong;Kim, Ki-Baek;Jung, Jae-Kwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.9
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    • pp.244-250
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    • 2017
  • The most important aspect determining the completeness of aprosthesis is itsmarginal and internal fit. Alloysare processed using a softening/hardening heat treatment methodin order to improve their mechanical, physical properties and polishing properties. To examinehow the heat treatment method affects the marginal and internal fit of the Ni-Cr alloy core,thirty dental stone models of the abutment of the mandibular left molar were manufactured.The Ni-Cr alloy coreswere manufactured by the dipping method for the experiment and dividedinto three groups; A for no heat treatment, B for softening heat treatment and C for hardening heat treatment. The marginal and internal fitsof all of the groups were measured by the silicone replica technique. A statistical analysis was performed using one-way ANOVA(${\alpha}=0.05$) in order to examine whether there is a significant difference in the average values of the marginal and internal fits among the three groups and it was found that themarginal fits (1, 6) were significantly different (p<0.05), but the internal fits (2, 3, 4, 5) were not significantly different (p>0.05). These results show that Ni-Cr alloys should not be processed bythe heat treatmentmethod.However, they need to be confirmed in further clinical application studies.

Influences of Moral Sensitivity and Safety Environment on Compliance with Standard Precautions among Nurses (간호사의 도덕적 민감성과 안전 환경이 감염 표준주의 이행도에 미치는 영향)

  • Han, Dallong;Seo, Kyoungsan;Kim, Eun-sook;Kim, Hae-Eun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.364-375
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    • 2018
  • This study was a descriptive investigation to identify the influence of nurses' moral sensitivity and safety of their environment on compliance with standard precautions. Participants consisted of 214 nurses in one general hospital and data were collected using a questionnaire that consisted of moral sensitivity, safety of environment and compliance with standard precautions from 1-15 August 2017. Data were evaluated by the independent t-test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis. The mean scores of moral sensitivity, safety of environment and compliance with standard precautions were 5.05, 5.76 and 4.50, respectively. Moreover, compliance with standard precautions was significantly positively correlated with moral sensitivity and safety of environment. Additionally, multiple regression revealed an $R^2$ of 0.253 with the department (ER, ICU), age and safety environment serving as the major predictor variables for compliance with standard precautions. However, the influence of moral sensitivity on compliance was not identified. Therefore, to increase compliance with standard precautions among nurses, it is necessary to provide continuous educational programs for new nurses, customized programs considering departmental characteristics and administrative support of institutions to enhance safety of the environment.

Development and Effect Verification of Situated Learning Theory-Applied Teaching-Learning Plans for the 'Clothing and Self-Expression' Unit of Seventh Grade Technology-Home Economics Subject (상황학습 이론을 적용한 중학교 1학년 기술.가정 교과의 '옷차림과 자기표현' 단원 교수-학습 과정안 개발 및 효과검증)

  • Hwang, Hye-Min;Lee, Yhe-Young;Ahn, So-Eun
    • Journal of Korean Home Economics Education Association
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    • v.25 no.1
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    • pp.67-77
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    • 2013
  • The purpose of this study was to develop teaching-learning plans for the 7th grade technology-home economics classes, applying situated learning theory. In addition, the effect of developed teaching-learning plans were examined, in terms of students' perception and attitude toward clothing habits and the degree of satisfaction with the lessons. In order to carry out the research, the teaching-learning plans for the 3 lessons on "clothing and self-expression" unit were developed. Experimental study was done at a middle school in Seoul to examine the effect of the teachig-learning plans developed based on the situated learning theory. Two classes taught with the developed teaching-learning plans served as a experiment group, and another two classes taught with traditional lecture-based plans served as a control group. As a result, teaching-learning plans developed based on situated learning theory had a positive impact on students' satisfaction with the lessons and the perception and attitude toward clothing habits.

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