• Title/Summary/Keyword: accuracy-study

Search Result 16,172, Processing Time 0.046 seconds

Analysis of Distance Measurement Accuracy in Aerial and Satellite Image Photogrammetry (항공사진측량과 위성영상측량에서 거리측정 정확도 연구)

  • Kim, Hyung-Moo;Tcha, Dek-Kie;Nam, Guon-Mo;Yang, Chul-Soo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2010.04a
    • /
    • pp.253-255
    • /
    • 2010
  • Needs to study on distance measurement accuracy in aerial and satellite photogrammetry are rapidly increased. However, conventional studies show some confused definitions between measurement accuracy and measurement precision as well as standard deviation(STDEV) and root mean square error(RMSE or RMSD). So, Finite definitions of measurement accuracy and measurement precision as well as STDEV and RMSD are addressed in this paper. Experiment result show using correct definitions improve the distance measurement accuracy in aerial and satellite photogrammetry rapidly, but not the distance measurement accuracy in aerial and satellite photogrammetry.

  • PDF

Diagnostic Accuracy of Dermoscopy for Scabies

  • Li, Feng-Zeng;Chen, Shuang
    • Parasites, Hosts and Diseases
    • /
    • v.58 no.6
    • /
    • pp.669-674
    • /
    • 2020
  • The diagnostic accuracy of dermoscopy (DS) for scabies, a highly contagious parasitic disease, remains disputed. This study aimed to assess the diagnostic accuracy of DS in scabies, analyze the factors influencing DS, and explore its role in post-treatment evaluation. Patients with suspected scabies were randomly divided into 2 groups: 71 patients in the skin scraping (SS) group and 73 patients in the DS group. The diagnostic efficiencies of SS and DS in these groups were calculated. We also analyzed the influence of body part and investigator competence on the accuracy of DS. Then 16 body parts with typical signs of scabies were monitored by DS 2 and 4 day after sulfur ointment treatment. The sensitivity and specificity of DS were 98.3% and 88.5%, respectively. Hands, arms, and the abdomen had higher positivity rates than other body parts (P<0.001). The accuracy of dermatologists' interpretations of images negative for scabies in the intermediate- and high-level groups was higher than that in the low-level group (P<0.001). At follow-up, the mites were still visible on 43.8% to 62.5% of the skin lesions 2 and 4 day after sulfur ointment treatment. These results showed that DS could significantly increase the accuracy of diagnosing scabies owing to its high sensitivity and specificity. Therefore, it may be useful for monitoring clinical responses to anti-parasitic treatment.

The Development of Exercise Accuracy Measurement Algorithm Supporting Personal Training's Exercise Amount Improvement

  • Oh, Seung-Taek;Kim, Hyeong-Seok;Lim, Jae-Hyun
    • International journal of advanced smart convergence
    • /
    • v.11 no.4
    • /
    • pp.57-67
    • /
    • 2022
  • The demand for personal training (PT), through which high exercise effects can be achieved within short-term, has recently increased. PT can achieve an exercise amount improvement effect, only if accurate postures are maintained upon performing PT, and exercise with inaccurate postures can cause injuries. However, research is insufficient on exercise amount comparisons and judging exercise accuracy on PT. This study proposes an exercise accuracy measurement algorithm and compares differences in exercise amounts according to exercise postures through experiments using a respiratory gas analyzer. The exercise accuracy measurement algorithm acquires Euler anglesfrom major body parts operated upon exercise through a motion device, based on which the joint angles are calculated. By comparing the calculated joint angles with each reference angle in each exercise step, the status of exercise accuracy is judged. The calculated results of exercise accuracy on squats, lunges, and push-ups showed 0.02% difference in comparison with actually measured results through a goniometer. As a result of the exercise amount comparison experiment according to accurate posture through a respiratory gas analyzer, the exercise amount was higher by 45.19% on average in accurate postures. Through this, it was confirmed that maintaining accurate postures contributes to exercise amount improvement.

Effect of the volumetric dimensions of a complete arch on the accuracy of scanners

  • Kim, Min-Kyu;Son, KeunBaDa;Yu, Beom-Young;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
    • /
    • v.12 no.6
    • /
    • pp.361-368
    • /
    • 2020
  • PURPOSE. The present study aimed to evaluate the accuracy of a desktop scanner and intraoral scanners based on the volumetric dimensions of a complete arch. MATERIALS AND METHODS. Seven reference models were fabricated based on the volumetric dimensions of complete arch (70%, 80%, 90%, 100%, 110%, 120%, and 130%). The reference models were digitized using an industrial scanner (Solutionix C500; MEDIT) for the fabrication of a computer-aided design (CAD) reference model (CRM). The reference models were digitized using three intraoral scanners (CS3600, Trios3, and i500) and one desktop scanner (E1) to fabricate a CAD test model (CTM). CRM and CTM were then superimposed using inspection software, and 3D analysis was conducted. For statistical analysis, one-way analysis of variance was used to verify the difference in accuracy based on the volumetric dimensions of the complete arch and the accuracy based on the scanners, and the differences among the groups were analyzed using the Tukey HSD test as a post-hoc test (α=.05). RESULTS. The three different scanners showed a significant difference in accuracy based on the volumetric dimensions of the complete arch (P<.05), but the desktop scanner did not show a significant difference in accuracy based on the volumetric dimensions of the complete arch (P=.808). CONCLUSION. The accuracy of the intraoral scanners was dependent on the volumetric dimensions of the complete arch, but the volumetric dimensions of the complete arch had no effect on the accuracy of the desktop scanner. Additionally, depending on the type of intraoral scanners, the accuracy differed according to the volumetric dimensions of the complete arch.

A study on the Accurate Comparison of Nonlinear Solution Which Used Tangent Stiffness Equation and Nonlinear Stiffness Equation (접선 강성방정식과 비선형 강성방정식을 이용한 비선형 해의 정확성 비교에 관한 연구)

  • Kim, Seung-Deog;Kim, Nam-Seok
    • Journal of Korean Association for Spatial Structures
    • /
    • v.10 no.2
    • /
    • pp.95-103
    • /
    • 2010
  • This paper study on the accuracy improvement of nonlinear stiffness equation. The large structure must have thin thickness for build the large space structure there fore structure instability review is important when we do structural design. The structure instability of the shelled structure is accept it sensitively by varied conditions. This come to a nonlinear problem with be concomitant large deformation. Accuracy of nonlinear stiffness equation must improve to examine structure instability. In this study, space truss is analysis model Among tangent stiffness equation and nonlinear stiffness equation is using nonlinearity analysis program. The study compares an analysis result to investigate accuracy and convergence properties improvement of nonlinear stiffness equation.

  • PDF

Comparative Study of Text Entry Speed and Accuracy Using the Three Different Keyboard Type in Students with Cerebral Palsy: Case Study (키보드 유형에 따른 뇌성마비 학생의 문자입력 속도 및 정확도 비교: 사례연구)

  • Jeong, Dong-Hoon
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.10 no.1
    • /
    • pp.23-35
    • /
    • 2015
  • PURPOSE: People with physical disabilities such as cerebral palsy usually experience obstacles when interacting with computer through conventional keyboard because of their motor disabilities. The purpose of this study is empirically compare of text entry(alphabet and word) speed and accuracy using the three different keyboard type on four students(male 2 and female 2) with cerebral palsy. METHODS: This research design used a replicated single-case experimental approach to compare the individual performance. An alternating treatments design was used to examine the effectiveness of standard QWERTY keyboard and alternative keyboard(mini and big keyboard) on computer access for students with cerebral palsy. To avoid changes in posture that influence a keyboard character entry training and evaluation was carried out using his sitting in a wheelchair. Compass software program used in this study as an assessment tool to measure speed and accuracy when performance of text entry(alphabet and word). This was repeated until the stable status of reaction time. RESULTS: As a result, the alternative keyboard seems to be the most effective device for students with cerebral palsy to perform text entry. But various factors such as peculiarity of motor disabilities, experience and preferences of the user are heavily related. CONCLUSION: Thus, we must perform the objective and systematic assessment for computer access and if sustained training is accomplished, it could to improve speed and accuracy of text entry(alphabet and word).

A Study on Accuracy of Position Analysis by Non-metric photo (비측량용 사진에 의한 위치해석의 정확도 연구)

  • 이종출;이병걸;심봉섭
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.13 no.1
    • /
    • pp.95-106
    • /
    • 1995
  • The purpose of this study is to analyse the accuracy of non-metric photos by close-range photogrammetry. Close-range photogrammetry using non-metric photos is 'economical and convenient to handle, but it is insufficient of study on accuracy. To execute this study, first, the terrain model was made and then taken photographs of this model with metric and non-metric cameras. The Bundle adjustment and the Direct linear transformation methods are used for the analysis close-range photogrammetry. The results of the analysis showed that the Bundle adjustment method is a appropriate method for the analysis of the non-netric photo. Therefore, we concluded that the accuracy of the non-metric photo by close-range photogrammetry is applicability for the photogrammetry.

  • PDF

Analysis of Accuracy and Reliability for OWAS, RULA, and REBA to Assess Risk Factors of Work-related Musculoskeletal Disorders (근골격계질환 유해요인 정밀조사를 위한 OWAS, RULA, REBA의 평가 정확도 및 신뢰도 분석)

  • Cheon, Woohyun;Jung, Kihyo
    • Journal of the Korea Safety Management & Science
    • /
    • v.22 no.2
    • /
    • pp.31-38
    • /
    • 2020
  • The study evaluated the accuracy and intra-rater reliability for OWAS (Ovako Working posture Analysing System), RULA (Rapid Upper Limb Assessment), REBA (Rapid Entire Body Assessment) to improve their evaluation accuracy and reliability. Participants (n = 163) with undergraduate degree were recruited in this study and trained for 6 hours about the ergonomic assessment methods. Ergonomic assessments were conducted using OWAS, RULA, and REBA for a representative work with dynamic posture found in manufacturing industries. The study compared action categories (overall level) and detailed evaluation scores for individual body part. Action categories of the participants significantly differed from the golden reference defined by ergonomic experts. The participants underrated or omitted scores for truck (37.4% of the participants) and legs (52.8%) in OWAS. Similarly, the participants underrated or omitted additional scores for all body parts except the hand and wrist in RULA (53.5%) and REBA (54.8%). On the other hand, the participants overrated scores for the hand and wrist in RULA (55.2%) and REBA (39.9%). The results found in this study can help of selecting focus points and parts during assessment and education to improve accuracy and reliability of the ergonomic assessment methods.

Development of a Machine-Learning based Human Activity Recognition System including Eastern-Asian Specific Activities

  • Jeong, Seungmin;Choi, Cheolwoo;Oh, Dongik
    • Journal of Internet Computing and Services
    • /
    • v.21 no.4
    • /
    • pp.127-135
    • /
    • 2020
  • The purpose of this study is to develop a human activity recognition (HAR) system, which distinguishes 13 activities, including five activities commonly dealt with in conventional HAR researches and eight activities from the Eastern-Asian culture. The eight special activities include floor-sitting/standing, chair-sitting/standing, floor-lying/up, and bed-lying/up. We used a 3-axis accelerometer sensor on the wrist for data collection and designed a machine learning model for the activity classification. Data clustering through preprocessing and feature extraction/reduction is performed. We then tested six machine learning algorithms for recognition accuracy comparison. As a result, we have achieved an average accuracy of 99.7% for the 13 activities. This result is far better than the average accuracy of current HAR researches based on a smartwatch (89.4%). The superiority of the HAR system developed in this study is proven because we have achieved 98.7% accuracy with publically available 'pamap2' dataset of 12 activities, whose conventionally met the best accuracy is 96.6%.