• Title/Summary/Keyword: 정확도평가

Search Result 3,586, Processing Time 0.03 seconds

Development of Estimation System for Housing Remodeling Cost through Influence Analysis by Design Elements (설계요소별 영향분석을 통한 공동주택 리모델링 공사비개산견적 산출 시스템 개발)

  • Kim, Jun;Cha, Heesung
    • Korean Journal of Construction Engineering and Management
    • /
    • v.19 no.6
    • /
    • pp.65-78
    • /
    • 2018
  • In As urban apartment are aging, the necessity of reconstruction or remodeling to extend the life of buildings is increasing. In such a case, a co-housing association is formed to implement decisions on reconstruction or remodeling projects. At this time, the most important thing for the co-housing association is the business feasibility based on the input of the construction cost.In the case of reconstruction, it is possible to estimate the construction cost by using the accumulated construction cost data, and then evaluate the feasibility using the construction cost. However, in case of remodeling, it is difficult to calculate the accurate construction cost because the number of accumulated construction cost data is small. In addition, non-specialist clients often require estimates of various design factors, often negatively impacting the accuracy of estimates and the duration of estimates. Therefore, in this study, proposed method to reflect the opinion of the owner who is a non-expert, as a design element, and a method of calculating the expected construction cost according to the design element, and constructed this system so that it can be easily used by the non-specialist owner. In order to clearly reflect the requirements of the non-specialist owner in the estimates, extracts the design elements from the existing remodeling cases, classify them, and suggest a plan for the client to choose. In order to reflect the design factors to the estimates, the existing apartment house remodeling cases were investigated and the design factors were extracted to have a large effect on the construction cost. Finally, developed system based on MS Excel so that the above contents can be easily used by a non-specialist client. In order to verify the accuracy of the proposed estimate in this study, verified the accuracy of 80% of the results by substituting the case of remodeling quotations and obtained a positive result from the questionnaire survey to examine the ease of use of the non-specialist customer. In this study, propose an estimate estimation method using four cases. If the remodeling cases are accumulated continuously, the expected effect of this study will be higher.

Validation of Extreme Rainfall Estimation in an Urban Area derived from Satellite Data : A Case Study on the Heavy Rainfall Event in July, 2011 (위성 자료를 이용한 도시지역 극치강우 모니터링: 2011년 7월 집중호우를 중심으로)

  • Yoon, Sun-Kwon;Park, Kyung-Won;Kim, Jong Pil;Jung, Il-Won
    • Journal of Korea Water Resources Association
    • /
    • v.47 no.4
    • /
    • pp.371-384
    • /
    • 2014
  • This study developed a new algorithm of extreme rainfall extraction based on the Communication, Ocean and Meteorological Satellite (COMS) and the Tropical Rainfall Measurement Mission (TRMM) Satellite image data and evaluated its applicability for the heavy rainfall event in July-2011 in Seoul, South Korea. The power-series-regression-based Z-R relationship was employed for taking into account for empirical relationships between TRMM/PR, TRMM/VIRS, COMS, and Automatic Weather System(AWS) at each elevation. The estimated Z-R relationship ($Z=303R^{0.72}$) agreed well with observation from AWS (correlation coefficient=0.57). The estimated 10-minute rainfall intensities from the COMS satellite using the Z-R relationship generated underestimated rainfall intensities. For a small rainfall event the Z-R relationship tended to overestimated rainfall intensities. However, the overall patterns of estimated rainfall were very comparable with the observed data. The correlation coefficients and the Root Mean Square Error (RMSE) of 10-minute rainfall series from COMS and AWS gave 0.517, and 3.146, respectively. In addition, the averaged error value of the spatial correlation matrix ranged from -0.530 to -0.228, indicating negative correlation. To reduce the error by extreme rainfall estimation using satellite datasets it is required to take into more extreme factors and improve the algorithm through further study. This study showed the potential utility of multi-geostationary satellite data for building up sub-daily rainfall and establishing the real-time flood alert system in ungauged watersheds.

Improvement of Mid-and Low-flow Estimation Using Variable Nonlinear Catchment Wetness Index (비선형 유역습윤지수를 이용한 평갈수기 유출모의개선)

  • Hyun, Sukhoon;Kang, Boosik;Kim, Jin-Gyeom
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.36 no.5
    • /
    • pp.779-789
    • /
    • 2016
  • The effective rainfall is calculated considering the soil moisture. It utilizes observed data directly in order to incorporate the soil moisture into the rainfall-runoff model, or it calculates indirectly within the model. The rainfall-runoff model, IHACRES, used in this study computes the catchment wetness index (CWI) first varying with temperature and utilize it for estimating precipitation loss. The nonlinear relationship between the CWI and the effective rainfall in the Hapcheondam watershed was derived and utilized for the long-term runoff calculation. The effects of variable and constant CWI during calibration and validation were suggested by flow regime. The results show the variable CWI is generally more effective than the constant CWI. The $R^2$ during high flow period shows relatively higher than the ones during normal or low flow period, but the difference between cases of the variable and constant CWI was insignificant. The results indicates that the high flow is relatively less sensitive to the evaporation and soil moisture associated with temperature. On the other hand, the variable CWI gives more desirable results during normal and low flow periods which means that it is crucial to incorporate evaporation and soil moisture depending on temperature into long-term continuous runoff simulation. The NSE tends to decrease during high flow period with high variability which could be natural because NSE index is largely influenced by outliers of underlying variable. Nevertheless overall NSE shows satisfactory range higher than 0.9. The utilization of variable CWI during normal and low flow period would improve the computation of long-term rainfall-runoff simulation.

Risk Factors of Cervical Cancer and Results of Cervix Cytology Screening in Chungnam Province, Korea, 1995-1999 (최근 5년간(1995-1999) 충남지역자궁경부세포진 검진결과 및 이상소견위험요인분석)

  • Lee, Moo-Sik;Lim, Yeon-Hwan;Kim, Eun-Young;Lee, Choong-Won
    • Journal of agricultural medicine and community health
    • /
    • v.26 no.2
    • /
    • pp.43-57
    • /
    • 2001
  • The purpose of this study was to evaluate results of cervix cytology screening in the community and to determine the risk factors of cervical abnormality. Branch of Daejeon city and Chungnam Province, The Planed Parenthood Federation of Korea had conducted cervical cancer screening of 146,848 married women in Chungnam province from 1995 to 1999. Cervical cancer screening was Pap smear using cytolgic brush swab by trained nurse. Women who had abnormal finding of 1st Pap smear screening were followed re- examination and 2nd close examination. Crude prevalence rate of cytologic abnormalities for 1st screening results was 0.63% in 1995- 1999(1995 0.68%, 1996 0.59%, 1997 0.70%, 1998 0.56%, 1999 0.62%). Crude prevalence rate of above class III for 1st screening results was 0.61%, but crude prevalence rate of above class III for the results of re- examination and 2nd close examination was 2.2/ 1000. The false-positive rate of class III, IV and V for positive findings were defined above class II(cervicitis) results were 52.6%, 26.9% and 19.0%, respectively. And the false- positive rate of class III, IV and V for positive findings were defined above class III(dysplasia) results were 75.3%, 46.2% and 47.6%, respectively. Major predictors of risk factors for abnormal results of cervix screening on the multiple logistic regression were age, educational attainment and living area. The false-positive rate of cervix cytology screening in the community were highest result so cervix cytology screening should be improve for better diagnostic power. And the finding of logistic regression would be understand within the limit of experimental trials on the relationship between cervical disease and risk factors.

  • PDF

Matching Points Filtering Applied Panorama Image Processing Using SURF and RANSAC Algorithm (SURF와 RANSAC 알고리즘을 이용한 대응점 필터링 적용 파노라마 이미지 처리)

  • Kim, Jeongho;Kim, Daewon
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.4
    • /
    • pp.144-159
    • /
    • 2014
  • Techniques for making a single panoramic image using multiple pictures are widely studied in many areas such as computer vision, computer graphics, etc. The panorama image can be applied to various fields like virtual reality, robot vision areas which require wide-angled shots as an useful way to overcome the limitations such as picture-angle, resolutions, and internal informations of an image taken from a single camera. It is so much meaningful in a point that a panoramic image usually provides better immersion feeling than a plain image. Although there are many ways to build a panoramic image, most of them are using the way of extracting feature points and matching points of each images for making a single panoramic image. In addition, those methods use the RANSAC(RANdom SAmple Consensus) algorithm with matching points and the Homography matrix to transform the image. The SURF(Speeded Up Robust Features) algorithm which is used in this paper to extract featuring points uses an image's black and white informations and local spatial informations. The SURF is widely being used since it is very much robust at detecting image's size, view-point changes, and additionally, faster than the SIFT(Scale Invariant Features Transform) algorithm. The SURF has a shortcoming of making an error which results in decreasing the RANSAC algorithm's performance speed when extracting image's feature points. As a result, this may increase the CPU usage occupation rate. The error of detecting matching points may role as a critical reason for disqualifying panoramic image's accuracy and lucidity. In this paper, in order to minimize errors of extracting matching points, we used $3{\times}3$ region's RGB pixel values around the matching points' coordinates to perform intermediate filtering process for removing wrong matching points. We have also presented analysis and evaluation results relating to enhanced working speed for producing a panorama image, CPU usage rate, extracted matching points' decreasing rate and accuracy.

Optimization of Image Tracking Algorithm Used in 4D Radiation Therapy (4차원 방사선 치료시 영상 추적기술의 최적화)

  • Park, Jong-In;Shin, Eun-Hyuk;Han, Young-Yih;Park, Hee-Chul;Lee, Jai-Ki;Choi, Doo-Ho
    • Progress in Medical Physics
    • /
    • v.23 no.1
    • /
    • pp.8-14
    • /
    • 2012
  • In order to develop a Patient respiratory management system includinga biofeedback function for4-dimentional radiation therapy, this study investigated anoptimal tracking algorithmfor moving target using IR (Infra-red) camera as well as commercial camera. A tracking system was developed by LabVIEW 2010. Motion phantom images were acquired using a camera (IR or commercial). After image process were conducted to convert acquired image to binary image by applying a threshold values, several edge enhance methods such as Sobel, Prewitt, Differentiation, Sigma, Gradient, Roberts, were applied. The targetpattern was defined in the images, and acquired image from a moving targetwas tracked by matching pre-defined tracking pattern. During the matching of imagee, thecoordinateof tracking point was recorded. In order to assess the performance of tracking algorithm, the value of score which represents theaccuracy of pattern matching was defined. To compare the algorithm objectively, we repeat experiments 3 times for 5 minuts for each algorithm. Average valueand standard deviations (SD) of score were automatically calculatedsaved as ASCII format. Score of threshold only was 706, and standard deviation was 84. The value of average and SD for other algorithms which combined edge detection method and thresholdwere 794, 64 in Sobel, 770, 101 in Differentiation, 754, 85 in Gradient, 763, 75 in Prewitt, 777, 93 in Roberts, and 822, 62 in Sigma, respectively. According to score analysis, the most efficient tracking algorithm is the Sigma method. Therefore, 4-dimentional radiation threapy is expected tobemore efficient if threshold and Sigma edge detection method are used together in target tracking.

Analysis of Diagnostic Performance of CT and EUS for Clinical TN Staging of Gastric Cancer (위암의 임상적 병기 설정을 위한 전산화단층촬영 및 초음파 내시경의 진단력 평가)

  • Shin, Ru-Mi;Lee, Ju-Hee;Lee, Moon-Soo;Park, Do-Joong;Kim, Hyung-Ho;Yang, Han-Kwang;Lee, Kuhn-Uk
    • Journal of Gastric Cancer
    • /
    • v.9 no.4
    • /
    • pp.177-185
    • /
    • 2009
  • Purpose: Preoperative clinical staging of gastric cancer is very important for determining the treatment plans and predicting the prognosis. The previous reports regarding the accuracy of computed tomography or endoscopic ultrasound for the preoperative staging of gastric cancer have shown various outcomes. We analyzed the diagnostic performance of CT and EUS, which are important staging tools for the staging of TN gastric cancer. Materials and Methods: We retrospectively analyzed 1,174 patients who underwent gastrectomy for gastric cancer at Seoul National University Bundang Hostpital from May, 2003 to December, 2007. We derived the Kappa value to examine the agreement of the preoperative staging obtained from CT and EUS with the pathological staging. Results: The mean age of the 1,174 patients was $59.31{\pm}11.98$ years. Six hundred thirty seven patients had early gastric cancer and 536 had advanced gastric cancer. The diagnostic performance between CT and EUS for the T staging showed no significant difference between CT and EUS for the kappa values. The kappa values showed moderate agreement at 0.4039 (P=0.021) and 0.4201 (P=0.026), respectively. This suggests that there is no difference between the two examinations for the overall T staging. Analysis of the discrimination of mucosal and submucosal lesions with EUS showed an accuracy of 58.92% and a Kappa value of 0.206 (P<0.001), suggesting fair agreement and a lower diagnostic performance than expected. To differentiate lesions with stages higher than or equal to T2 or T3 from the lesion with stages lower than T2 or T3, respectively, adoption of the higher stage from the CT staging or the EUS staging showed a larger AUC of 0.84 than that from either stage alone. The CT-derived node stage had the higher diagnostic performance (68.55%) than that of the EUS-derived node stage (60.82%) for the node staging. Conclusion: The CT-derived stage and EUS-derived stage showed comparable results for determining the T stage of gastric cancer. Yet the higher stage of the two stages from CT and EUS most accurately discriminated between those lesions with stages higher than T2 and those lesions with stages lower than T2.

  • PDF

Improvement of Radar Rainfall Estimation Using Radar Reflectivity Data from the Hybrid Lowest Elevation Angles (혼합 최저고도각 반사도 자료를 이용한 레이더 강우추정 정확도 향상)

  • Lyu, Geunsu;Jung, Sung-Hwa;Nam, Kyung-Yeub;Kwon, Soohyun;Lee, Cheong-Ryong;Lee, Gyuwon
    • Journal of the Korean earth science society
    • /
    • v.36 no.1
    • /
    • pp.109-124
    • /
    • 2015
  • A novel approach, hybrid surface rainfall (KNU-HSR) technique developed by Kyungpook Natinal University, was utilized for improving the radar rainfall estimation. The KNU-HSR technique estimates radar rainfall at a 2D hybrid surface consistings of the lowest radar bins that is immune to ground clutter contaminations and significant beam blockage. Two HSR techniques, static and dynamic HSRs, were compared and evaluated in this study. Static HSR technique utilizes beam blockage map and ground clutter map to yield the hybrid surface whereas dynamic HSR technique additionally applies quality index map that are derived from the fuzzy logic algorithm for a quality control in real time. The performances of two HSRs were evaluated by correlation coefficient (CORR), total ratio (RATIO), mean bias (BIAS), normalized standard deviation (NSD), and mean relative error (MRE) for ten rain cases. Dynamic HSR (CORR=0.88, BIAS= $-0.24mm\;hr^{-1}$, NSD=0.41, MRE=37.6%) shows better performances than static HSR without correction of reflectivity calibration bias (CORR=0.87, BIAS= $-2.94mm\;hr^{-1}$, NSD=0.76, MRE=58.4%) for all skill scores. Dynamic HSR technique overestimates surface rainfall at near range whereas it underestimates rainfall at far ranges due to the effects of beam broadening and increasing the radar beam height. In terms of NSD and MRE, dynamic HSR shows the best results regardless of the distance from radar. Static HSR significantly overestimates a surface rainfall at weaker rainfall intensity. However, RATIO of dynamic HSR remains almost 1.0 for all ranges of rainfall intensity. After correcting system bias of reflectivity, NSD and MRE of dynamic HSR are improved by about 20 and 15%, respectively.

Preoperative Detection of Hepatic Metastases from the colorectal Cancers: Comparison of Dual-phase CT scan, Mn-DPDP enhanced MRI, and combination of CT and MRI (대장암의 간 전이 진단: 이중시기 CT, Mn-DPDP 조영증강 MRI, 그리고 CT-MRI 종합 판독의 비교)

  • Shin, Kyung-Min;Kim, Jong-Yeol;Choi, Gyu-Seok;Kim, Hye-Jeong;Lee, Jong-Min;Chang, Yong-Min;Kim, Yong-Seon;Kang, Duk-Sik;Ryeom, Hun-Kyu
    • Investigative Magnetic Resonance Imaging
    • /
    • v.9 no.2
    • /
    • pp.109-116
    • /
    • 2005
  • Purpose : To determine the usefulness of additional Mn-DPDP MRI for preoperative evaluation of the patients with colorectal cancers by comparison of dual-phase CT scan, Mn-DPDP enhanced MRI and combination of CT and MRI. Materials and Methods : Fifty-three colorectal cancer patients with 92 metastatic nodules underwent dualphase (arterial and portal) helical CT scan and Mn-DPDP MRI prior to surgery. The indication of MRI was presence or suspected of having metastatic lesions at CT scan and/or increased serum carcinoembryonic antigen (CEA) levels (10 ng/mL or more). The diagnosis was established by the combination of findings at surgery, intraoperative ultrasonography, and histopathologic examination. Two radiologists interpreted CT, MRI, and combination of CT-MRI at discrete sessions and evaluated each lesion for location, size, and intrinsic characteristics. The lesions were divided into three groups according to their diameter; 1cm<, 1-2 cm, and >2 cm. Diagnostic accuracy was evaluated using the alternative-free response receiver operating characteristic method. Detection and false positive rate were also evaluated. Results : In the lesions smaller than 1 cm, detection rate of combined CT-MRI was superior to CT or MRI alone (82%, p=0.036). The mean accuracy (Az values) of combined CT and MRI was significantly higher than that of CT in the lesions smaller than 2 cm (1 cm<, p=0.034; 1-2 cm, p=0.045). However, there was no significant difference between MRI and combined CT-MRI. The false positive rate of CT was higher than those of combined CT-MR in the lesions smaller than 1 cm (28%, p=0.023). Conclusion : Additional MRI using Mn-DPDP besides routine CT scan was helpful in differentiating the hepatic lesions (<2 cm) and could improve detection of the small hepatic metastases (<1 cm) from colorectal carcinoma.

  • PDF

Ictal Cerebral Perfusion Patterns in Partial Epilepsy: SPECT Subtraction (부분적 간질에서 SPECT Subtraction을 이용한 발작 중 뇌혈류 변화에 대한 연구)

  • Lee, Hyang-Woon;Hong, Seung-Bong;Tae, Woo-Suk;Kim, Sang-Eun;Seo, Dae-Won;Jeong, Seung-Cheol;Yi, Ji-Young;Hong, Seung-Chyul
    • The Korean Journal of Nuclear Medicine
    • /
    • v.34 no.3
    • /
    • pp.169-182
    • /
    • 2000
  • Purpose: To investigate the various ictal perfusion patterns and find the relationships between clinical factors and different perfusion patterns. Materials and Methods: Interictal and ictal SPECT and SPECT subtraction were performed in 61 patients with partial epilepsy. Both positive images showing ictal hyperperfusion and negative images revealing ictal hypoperfusion were obtained by SPECT subtraction The ictal perfusion patterns of subtracted SPECT were classified into focal hyperperfusion, hyperperfusion-plus, combined hyperperfusion-hypoperfusion, and focal hypoperfusion only. Results: The concordance rates with epileptic focus were 91.8% in combined analysis of ictal hyperperfusion and hypoperfusion images of subtracted SPECT, 85.2% in hyperperfusion images only of subtracted SPECT, and 68.9% in conventional ictal SPECT analysis. Ictal hypoperfusion occurred less frequently in temporal lobe epilepsy (TLE) than extratemporal lobe epilepsy. Mesial temporal hyperperfusion alone was seen only in mesial TLE while lateral temporal hyperperfusion alone was observed only in neocortical TLE. Hippocampal sclerosis had much lower incidence of ictal hypoperfusion than any other pathology. Some patients showed ictal hypoperfusion at epileptic focus with ictal hyperperfusion in the neighboring brain regions where ictal discharges propagated. Conclusion: Hypoperfusion as well as hyperperfusion in ictal SPECT should be considered for localizing epileptic focus. Although the mechanism of ictal hypoperfusion could be an intra-ictal early exhaustion of seizure focus or a steal phenomenon by the propagation of ictal discharges to adjacent brain areas, further study is needed to elucidate it.

  • PDF