• 제목/요약/키워드: Area under the curve

검색결과 1,260건 처리시간 0.029초

Modeling the Spatial Distribution of Black-Necked Cranes in Ladakh Using Maximum Entropy

  • Meenakshi Chauhan;Randeep Singh;Puneet Pandey
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제4권2호
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    • pp.79-85
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    • 2023
  • The Tibetan Plateau is home to the only alpine crane species, the black-necked crane (Grus nigricollis). Conservation efforts are severely hampered by a lack of knowledge on the spatial distribution and breeding habitats of this species. The ecological niche modeling framework used to predict the spatial distribution of this species, based on the maximum entropy and occurrence record data, allowed us to generate a species-specific spatial distribution map in Ladakh, Trans-Himalaya, India. The model was created by assimilating species occurrence data from 486 geographical sites with 24 topographic and bioclimatic variables. Fourteen variables helped forecast the distribution of black-necked cranes by 96.2%. The area under the curve score for the model training data was high (0.98), indicating the accuracy and predictive performance of the model. Of the total study area, the areas with high and moderate habitat suitability for black-necked cranes were anticipated to be 8,156 km2 and 6,759 km2, respectively. The area with high habitat suitability within the protected areas was 5,335 km2. The spatial distribution predicted using our model showed that the majority of speculated conservation areas bordered the existing protected areas of the Changthang Wildlife Sanctuary. Hence, we believe, that by increasing the current study area, we can account for these gaps in conservation areas, more effectively.

적외선 체열 촬영을 이용한 수부냉증 진단의 절단값 산정 (The Cut Off Values for Diagnosing Cold Hypersensitivity of Hands by Using Digital Infrared Thermographic Imaging)

  • 조준영;박경선;이창훈;장준복;이경섭;이진무
    • 대한한방부인과학회지
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    • 제25권3호
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    • pp.95-102
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    • 2012
  • Purpose: The purpose of this study is to define the cut off values of cold hypersensitivity of hands by using digital infrared thermographic imaging(DITI). Methods: Thermographic images of 130 patients with cold hypersensitivity of hands(CHHG, n=65) and non-cold hypersensitivity of hands(NCHHG, n=65) were retrospectively reviewed. We used the temperature difference the palm(PC8) and the upper arm(LU4) for diagnosing cold hypersensitivity of hands. The temperature differences of between two groups were analysed using independent samples t-tests. The cut off values were calculated by ROC curve analysis. Analyses were undertaken using SPSS version 17.0. P value of < 0.05 was considered significant. Results: The temperature difference the palm(PC8) and the upper arm(LU4) were significantly different between groups(p < 0.001). Using receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve were 70.8%, 73.8%, respectively both hands. The AUC was 0.822 on right hand and 0.818 on left hand. The optimum cut-off value was defined as $-0.05^{\circ}C$. Conclusions: These results suggest that DITI is a reliable instrument for estimating the cold hypersensitivity of hands.

Minimal clinically important difference of mouth opening in oral submucous fibrosis patients: a retrospective study

  • Kaur, Amanjot;Rustagi, Neeti;Ganesan, Aparna;PM, Nihadha;Kumar, Pravin;Chaudhry, Kirti
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제48권3호
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    • pp.167-173
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    • 2022
  • Objectives: The purpose of this study was to estimate the minimal clinically important difference (MCID) of mouth opening (MO) and patient satisfaction in surgically treated oral submucous fibrosis (OSMF) patients. Materials and Methods: The status of MO was collected preoperatively (T0), postoperatively at 3 months (T1), and at a minimum of 6 months postoperatively (T2). MCID was determined through the anchor-based approach with the change difference method, mean change method, and receiver operator characteristic curve (ROC) method. Results: In this study, 35 patients enrolled and completed postoperative follow-up (T2) averaging a duration of 18.1 months. At T1, using the change difference method, MO was 14.89 mm and the ROC curve exhibited a 11.5 gain in MO (sensitivity 81.8% and specificity 100%, area under the curve [AUC] of 0.902) and was classified as MCID as reported by patients. At T2, MCID of MO was 9.75 mm using the change difference method and 11.75 mm by the mean change method. The ROC curve revealed that the MCID of MO at T2 was 10.5 mm with 73.9% sensitivity and 83.3% specificity (AUC of 0.873). The kappa value was 0.91, confirming reliability of the data. Conclusion: This study demonstrated MCID values that indicate the clinical relevance of surgical treatment of OSMF if the minimum possible gain in MO is approximately 10 mm.

적외선 체열 촬영을 이용한 안면홍조 진단의 절단값 산정 (The Cut Off Values for Diagnosing Hot flashes by Using Digital Infrared Thermographic Imaging)

  • 조준영;황덕상;이창훈;장준복;이경섭;이진무
    • 대한한방부인과학회지
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    • 제26권3호
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    • pp.85-92
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    • 2013
  • Objectives: The purpose of this study is to find diagnostic points and define the cut off values of hot flashes by using digital infrared thermographic imaging. Methods: Thermographic images of 75 patients with hot flashes (HF, n=35) and non-hot flashes (NHF, n=40) were retrospectively reviewed. We used the temperature difference between Ex-HN3 and CV17, LU4, CV12, CV4 for diagnosing hot flashes. The temperature differences of between two groups were analysed using independent samples t-tests. The cut off values were calculated by received operating characteristic curve analysis. Analyses were undertaken using SPSS version 17.0. and p-value of <0.05 was considered significant. Results: The temperature difference Ex-HN3 and LU4 were the most significantly different between groups (p<0.001). Using receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve were 65.7%, 72.5%, 0.729, respectively. The optimum cut off value was defined as $1.00^{\circ}C$. Conclusions: These results suggest that the digital infrared thermographic imaging is a reliable instrument for estimating hot flashes.

갑상샘 악성결절의 초음파영상에서 GLCM 알고리즘을 이용한 세포병리 진단의 후향적 분석 (Retrospective Analysis of Cytopathology using Gray Level Co-occurrence Matrix Algorithm for Thyroid Malignant Nodules in the Ultrasound Imaging)

  • 김영주;이진수;강세식;김창수
    • 대한방사선기술학회지:방사선기술과학
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    • 제40권2호
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    • pp.237-243
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    • 2017
  • 본 연구는 갑상샘 초음파 영상에서 정상 및 악성결절의 세포병리 진단결과를 바탕으로 GLCM 알고리즘분석을 통한 후향적 연구를 시행하여 컴퓨터보조진단의 적용 가능성을 평가하였다. GLCM 알고리즘의 6가지 파라미터를 이용한 갑상샘 악성결절의 인식률 평가와 ROC 곡선을 분석하였다. 실험 결과는 에너지 97%, 대조도 93%, 상관관계 92%, 동질성 92%, 엔트로피 100%, 분산 100%의 높은 질환인식률을 나타내었다. ROC 곡선 분석에서 각 파라미터의 곡선아래면적이 0.947(p=0.001) 이상을 나타내어 갑상샘 악성결절의 인식에 의미가 있는 결과로 나타났다. 또한 GLCM에서 각 파라미터의 cut-off값 결정으로 정량적인 컴퓨터보조진단의 분석을 통한 질환예측이 가능할 것으로 판단된다.

GARP 모형과 기후변화 시나리오에 따른 잣나무의 지리적 분포 변화 (Shifts of Geographic Distribution of Pinus koraiensis Based on Climate Change Scenarios and GARP Model)

  • 천정화;이창배;유소민
    • 한국농림기상학회지
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    • 제17권4호
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    • pp.348-357
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    • 2015
  • 본 연구는 그간 우리나라에서 경제적인 가치를 인정 받아온 수종인 잣나무를 대상으로 잣나무의 현존 분포를 파악하고, RCP (Representative Concentration Pathway) 8.5 기후변화 시나리오와 생태적 지위 모형에 기반하여 향후 잣나무의 분포 변화를 예측하기 위해 수행되었다. 이를 위해 5년간의 NFI 자료에서 조사지점별 잣나무의 풍부도 자료를 추출하여 사용하였으며, 수종에 영향을 미치는 환경요인변수를 선정하기 위해 생태적 지위 모형 가운데 하나인 GARP (Genetic Algorithm for Rule-set Production)를 이용하였다. 총 27개의 환경요인변수에 대해 각각 모형을 구동하고 컨퓨전 매트릭스(Confusion Matrix) 기반 산출 통계량인 AUC (Area Under Curve)가 0.6 이상인 변수들을 선발하여 최종 잠재분포모형을 작성하였다. 그 결과 작성된 모형은 비교적 높은 적합도를 나타냈는데 잣나무는 현재 표고의 범위가 300m에서 1,200m 사이인 지역 및 남부에서 북부에 이르기까지 넓게 자리 잡고 있는 것으로 나타났다. 작성된 모형에 RCP 8.5 기후변화 시나리오를 적용한 결과, 잣나무는 2020년대부터 잠재분포역이 큰 폭으로 축소되며, 2090년대에는 우리나라 대부분의 지역이 잣나무의 생육에 불리할 것으로 예측되었다. 본 연구를 통해 기후변화가 잣나무 분포에 미치는 영향을 파악하고, 잣나무와 기후변화와의 상관성에 대한 이해를 높임으로써 향후 지역별 조림수종 선정 및 경제수종 교체 등의 조림적 관점에서 도움이 될 수 있을 것으로 판단된다.

The role of the iliotibial band cross-sectional area as a morphological parameter of the iliotibial band friction syndrome: a retrospective pilot study

  • Park, Jiyeon;Cho, Hyung Rae;Kang, Keum Nae;Choi, Kun Woong;Choi, Young Soon;Jeong, Hye-Won;Yi, Jungmin;Kim, Young Uk
    • The Korean Journal of Pain
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    • 제34권2호
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    • pp.229-233
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    • 2021
  • Background: Iliotibial band friction syndrome (ITBFS) is a common disorder of the lateral knee. Previous research has reported that the iliotibial band (ITB) thickness (ITBT) is correlated with ITBFS, and ITBT has been considered to be a key morphologic parameter of ITBFS. However, the thickness is different from inflammatory hypertrophy. Thus, we made the ITB cross-sectional area (ITBCSA) a new morphological parameter to assess ITBFS. Methods: Forty-three patients with ITBFS group and from 43 normal group who underwent T1W magnetic resonance imaging were enrolled. The ITBCSA was measured as the cross-sectional area of the ITB that was most hypertrophied in the magnetic resonance axial images. The ITBT was measured as the thickest site of ITB. Results: The mean ITBCSA was 25.24 ± 6.59 ㎟ in the normal group and 38.75 ± 9.11 ㎟ in the ITBFS group. The mean ITBT was 1.94 ± 0.41 mm in the normal group and 2.62 ± 0.46 mm in the ITBFS group. Patients in ITBFS group had significantly higher ITBCSA (P < 0.001) and ITBT (P < 0.001) than the normal group. A receiver operator characteristic curve analysis demonstrated that the best cut-off value of the ITBT was 2.29 mm, with 76.7% sensitivity, 79.1% specificity, and area under the curve (AUC) 0.88. The optimal cut-off score of the ITBCSA was 30.66 ㎟, with 79.1% sensitivity, 79.1% specificity, and AUC 0.87. Conclusions: ITBCSA is a new and sensitive morphological parameter for diagnosing ITBFS, and may even be more accurate than ITBT.

3. 간척지에서 수도개체군과 재식밀도에 관하여 (Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas 3. Response of Rice to Plant Population and Spacing in the Slty Soil Area)

  • 임형빈
    • Journal of Plant Biology
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    • 제12권2호
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    • pp.28-42
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    • 1969
  • Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

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65세 이상 고령자에서 대사증후군 예측을 위한 지질비율 지표의 유용성 비교 (Comparison of the Usefulness of Lipid Ratio Indicators for Prediction of Metabolic Syndrome in the Elderly Aged 65 Years or Older)

  • 신경아;김은재
    • 한국융합학회논문지
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    • 제13권1호
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    • pp.399-408
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    • 2022
  • 본 연구에서는 65세 이상 고령자를 대상으로 대사증후군 진단을 위한 지질비율 지표의 유용성을 비교하고자 하였다. 2018년 1월부터 2020년 12월까지 서울지역 종합병원에서 건강검진을 받은 65세 이상 1,464명을 대상으로 하였다. 혈액검사를 통해 혈장 동맥경화 지수를 포함한 지질비율 지표를 측정하였다. 지질비율 지표의 사분위수에 따른 대사증후군 유병률은 로지스틱 회귀분석으로 확인하였다. 또한 수신자 조작 특성(receiver operating characteristic, ROC) 곡선으로 지질비율 지표의 대사증후군 예측능력과 절단값을 추정하였다. 동맥경화 지수와 허리둘레의 상관성이 남녀 모두에서 가장 높았으며(r=0.278, p<0.001 vs r=0.252, p<0.001), 지질비율 지표는 1사분위수와 비교하여 4사분위수에서 대사증후군 발병률이 높았다. 혈장 동맥경화 지수는 다른 지질비율 지표보다 ROC 곡선 아래의 면적(area under the ROC curve; AUC)값이 남녀 각각 0.826(95% CI=0.799-0.850), 0.852(95% CI=0.820-0.881)로 가장 높게 나타났으며, 최적 절단값은 남녀 모두 0.44였다(p<0.001). 따라서 지질비율 지표 중 혈장 동맥경화 지수는 65세 이상 고령자의 대사증후군 진단에 가장 유용한 지표로 나타났다.

Texture Analyzer (TA)를 이용한 화장품 크림의 In Vivo 끈적임 평가법의 최적화 (Optimization of In Vivo Stickiness Evaluation for Cosmetic Creams Using Texture Analyzer)

  • 류주연;배정은;강내규
    • 대한화장품학회지
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    • 제46권4호
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    • pp.371-382
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    • 2020
  • 화장품의 사용감을 관계 있는 물성의 측정을 통해 정량화하려는 시도가 이어져오고 있다. 그 중 끈적임은 texture ananlyzer를 이용하여 수직 힘을 측정하는 방식이 대표적이며, 시간에 따른 수직 힘의 그래프에서 음의 면적인 area under curve (AUC)와 상관관계를 갖는 것으로 알려져 있다. 최근 노르망디 대학에서는 이러한 특성에 피부의 특성을 함께 고려하여 TA를 이용한 in vivo 끈적임 평가법을 개발하였다[8]. 본 연구에서는 이를 확장하여 화장품 크림의 in vivo 끈적임 평가법을 최적화하고자 하였다. 페이셜 크림 5 종을 대상으로 크림의 도포량 및 도포 횟수, 탐침의 모양과 소재를 바꾸어 보면서 실험을 진행하였고, 관능 평가 결과를 기준으로 가장 부합하는 조건을 최적의 평가법으로 설정하였다. 그 결과, 3.4 cm의 원 내부에 70 μL의 크림을 7 s 동안 10 회 문지르고 측정하는 방식이 가장 적합한 것으로 판단되었다. 탐침의 경우, 원기둥형보다 구형의 탐침이 재현성이 높게 나타나 구형의 금속 탐침을 택하였다. 최적의 평가법을 확보하여 10 인의 피험자를 대상으로 인체 평가를 진행한 결과, 사람에 따른 절대값에는 차이가 있으나 AUC의 순위는 모두 같게 얻어졌다. 마지막으로 AUC의 끈적임 표준화의 시도로 PVP를 표준 물질로 설정하여 농도 별로 AUC를 측정하고, 5종의 크림 별 끈적임 인지율을 확인하여 AUC와 끈적임의 상관관계에 대해 알아보았다.