• Title/Summary/Keyword: prism test

Search Result 109, Processing Time 0.028 seconds

Smart Device System for Strabismus Diagnosis (사시 진단을 위한 스마트 디바이스 시스템)

  • Yoon, Woong Bae;Oh, Ji Eun;Moon, Hyo Won;Yang, Hee Kyung;Hwang, Jeong Min;Park, Jong Il;Kim, Kwang Gi
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.8
    • /
    • pp.1538-1543
    • /
    • 2016
  • Strabismus is a non-aligned state;the visual axis of each eye is not directed toward the same direction at the same time. Clinically, the degrees of strabismus are measured by prism cover test, corneal reflex test (Hirschberg test), prism reflex test (Krimsky prism test), But corneal reflex test and prism reflex test is a possibility that errors occur. we suggest a computer-aided diagnosis for strabismus. We made a mobile application to measure angles of strabismus. For 34 patients, we tested our application. The result of comparing between two methods, It showed a difference 7 Prism Diopter(PD). Our application gives strabismus angles just using a camera and a smart device. Therefore, it can reduce the cost and make the diagnosis of strabismus accurate.

Prism-based Mesh Culling Method for Effective Continuous Collision Detection (효율적인 연속 충돌감지를 위한 프리즘 기반의 메쉬 컬링 기법)

  • Woo, Byung-Kwang;You, Hyo-Sun;Choi, Yoo-Joo
    • Journal of the Korea Computer Graphics Society
    • /
    • v.15 no.4
    • /
    • pp.1-11
    • /
    • 2009
  • In this paper, we present a prism-based mesh culling method to improve effectiveness of continuous collision detection which is a major bottleneck in a simulation using polygonal mesh models. A prism is defined based on two matching triangles between a sequence of times m a polygonal model. In order to detect potential colliding set(PCS) of prism between two polygonal models in a unit time, we apply the visibility test based on the occlusion query to two sets of prisms which are defined from two polygonal models in a unit time. Moreover, we execute the narrow band culling based on SAT(Separating Axis Test) to define potential colliding prism pairs from PCS of prisms extracted as a result of the visibility test. In the SAT, we examine one axis to be perpendicular to a plane which divides a 3D space into two half spaces to include each prism. In the experiments, we applied the proposed culling method to pairs of polygonal models with the different size and compared the number of potential colliding prism pairs with the number of all possible prism pairs of two polygonal models. We also compared effectiveness and performance of the visibility test-based method with those of the SAT-based method as the second narrow band culling. In an experiment using two models to consist of 2916 and 2731 polygons, respectively, we got potential colliding prism pairs with 99 % of culling rate.

  • PDF

Comparisons of Phoria Test Among Prism Settings of Von Graefe Technique (Von Graefe법의 프리즘 세팅에 따른 사위검사의 비교)

  • Yu, Dong-Sik;Ha, Eun-Mi
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.20 no.2
    • /
    • pp.211-218
    • /
    • 2015
  • Purpose: The aim of this study was to compare the differences among prism settings of the von Graefe technique for phoria measurement. Methods: Thirty eight healthy subjects (mean age $22.35{\pm}2.72years$) were tested with eye examination by interview, cover test, and refraction. Phorias were measured in a random order using four prism settings for the von Graefe method: base-in (BI) and base-up (BU), BI and base-down (BD), BU and BI, and BD and BI over the right and left eye, respectively. Results: Among the four prism settings in measurements of lateral and vertical phoria, there were not significant differences at distance, whereas there were significant at near. The reliability of near lateral phoria (ICC: 0.95) was good, but that of near vertical phoria was less reliable (ICC: 0.83). In comparisons of the paired t-test, the 95% limits of agreement, and mean difference between prism settings, BU had more useful than other prism settings at near phoria. Conclusions: Results from this study suggest that the von Graefe test with BU or BU including other setting prisms have useful methods, especially for near phoria measurements.

Two-axis latera I-shearing interferometer for performance test of lenses using a Dove prism (도브 프리즘을 이용한 렌즈 성능평가용 2축 층밀리기 간섭계)

  • 김승우;이혁교;김병창
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1995.10a
    • /
    • pp.384-387
    • /
    • 1995
  • Two axes lateral-shearing interferometer(LSI) specially devised for production line inspection lenses is presented. The interferometer composed with four prisms and a dove prism can test the lens performance including asymmetric aspheric lens. The dove prism which rotates the input image with respect to optical axis makes it possible. The wavefront passing through the test lens is reconstsucted by the phase derivative obtained form the two axes LSI system. Zernike-polynomials fitting of this wavefront is presented for determinating quantitative aberration of aspherical lenses.

  • PDF

High Brightness Prism Light-guide Plate for TFT-LCDs Using Optical Simulation and Novel Injection Mold Process (광학시뮬레이션과 새로운 사출성형법을 사용한 TFT-LCD용 고휘도 프리즘 도광판)

  • Han, Jeong-Min;Shon, Jin-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.61 no.2
    • /
    • pp.93-96
    • /
    • 2012
  • We have designed high performance prism light-guide plate (LGP) in 17 inch TFT-LCD. In test result to embody high brightness BLU in case of LGP of base and upper surface with 17 inch, thickness 8mm adding prism construct. Using optical simulation, we forecast the brightness and uniformity in LGP with prism structure. And we adopted novel injection mold method and Nickel stamper to make actual evolution sample. Novel injection mold process has steady heating time zone in heat cycle time of injection mold process. For this novel heat cycle control, we achieved above 90[%] height prism structure as our design. It is superior brightness improvement than previous that of printing form about some 20[%] and in this course to embody actual material it succeeded prism LGP production by 17 inch injection form process.

Pressure measurements on inclined square prisms

  • Hu, Gang;Tse, K.T.;Kwok, K.C.S.;Chen, Z.S.
    • Wind and Structures
    • /
    • v.21 no.4
    • /
    • pp.383-405
    • /
    • 2015
  • This study investigated aerodynamic characteristics of an inclined square prism experimentally. Pressure measurements were performed on a static square prism with a series of inclinations including forward inclinations (inclined to the upwind direction) and backward inclinations (inclined to the downwind direction). The prism with a vertical attitude was also tested for comparisons. Based on the pressure data, influences of the inclinations on aerodynamic characteristics (e.g., force coefficients, pressure distributions on the surfaces, and vortex shedding features) of the square prism were evaluated in detail. The results show that the inclinations have significant effects on these aerodynamic characteristics. Furthermore, the influences of the forward and backward inclinations are quite different.

Construction and actual material test of prism LGP not using function characteristic optical sheet for production of high brightness Back Light Unit

  • Han, J.M.;Yoon, D.K.;Park, D.S.;Oh, Y.S.;Bae, K.W.;Kim, Y.H.;Lim, Y.J.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.1233-1235
    • /
    • 2004
  • We have designed High Performance Prism LGP in 17 inch TFT-LCD. In test result to embody high brightness BLU in case of LGP of base and upper surface with 17 inch, thickness 8mm adding prism construct, it is superior brightness improvement than previous that of printing form about some 20% and in this course to embody actual material it succeeded prism LGP production by 17 inch injection form process.

  • PDF

Comparison of Alkali-Silica Reactivity for Mortar Bar and Concrete Prism Specimens Using Crushed Aggregates in Korea (국내 쇄석골재를 사용한 모르타르 봉 및 콘크리트 각주 시험편의 알칼리-실리카 반응성 비교)

  • Kim, Seong-Kwon;Yun, Kyong-Ku;Hur, In
    • International Journal of Highway Engineering
    • /
    • v.14 no.5
    • /
    • pp.93-99
    • /
    • 2012
  • PURPOSES: The purpose of this study is to compare the alkali-silica reactivity for mortar bar and concrete prism specimens using crushed aggregates of 5 types in Korea. And the alkali-silica reactivity for those aggregates are measured by chemical test method. METHODS: The alkali-silica reactivity for those aggregates was measured by chemical test method of KS F 2545, mortar-bar test of KS F 2546, accelerated mortar-bar test method of ASTM C 1260 and concrete prism test method of ASTM C 1293, relatively. RESULTS: The alkali-silica reactivity for those aggregates was verified by chemical test of KS F 2546 and accelerated mortar-bar test of ASTM C 1260. However, it was not by mortar-bar test of KS F 2546 and concrete prism test of ASTM C 1293. CONCLUSIONS: The above results showed that relationship among the four test methods were very low. The results from 3 types of test methods using cement-aggregate combinations appeared to be different. Because the environmental conditions of test methods for measuring the alkali-silica reactivity such as equivalent alkali content(external source), humidity, temperature, and times were different though the aggregates were same. Moreover, alkali-silica reactivity showed the biggest impact when alkalis were supplied form outside and exposed to environmental conditions. The accelerated mortar-bar test method seems to be most appropriate test method for concrete structures exposed to alkali environment.

Performance effectiveness of pediatric index of mortality 2 (PIM2) and pediatricrisk of mortality III (PRISM III) in pediatric patients with intensive care in single institution: Retrospective study (단일 병원에서 소아 중환자의 예후인자 예측을 위한 PIM2 (pediatric index of mortality 2)와 PRIMS III (pediatric risk of mortality)의 유효성 평가 - 후향적 조사 -)

  • Hwang, Hui Seung;Lee, Na Young;Han, Seung Beom;Kwak, Ga Young;Lee, Soo Young;Chung, Seung Yun;Kang, Jin Han;Jeong, Dae Chul
    • Clinical and Experimental Pediatrics
    • /
    • v.51 no.11
    • /
    • pp.1158-1164
    • /
    • 2008
  • Purpose : To investigate the discriminative ability of pediatric index of mortality 2 (PIM2) and pediatric risk of mortality III (PRISM III) in predicting mortality in children admitted into the intensive care unit (ICU). Methods : We retrospectively analyzed variables of PIM2 and PRISM III based on medical records with children cared for in a single hospital ICU from January 2003 to December 2007. Exclusions were children who died within 2 h of admission into ICU or hopeless discharge. We used Students t test and ANOVA for general characteristics and for correlation between survivors and non-survivors for variables of PIM2 and PRISM III. In addition, we performed multiple logistic regression analysis for Hosmer-Lemeshow goodness-of-fit, receiver operating characteristic curve (ROC) for discrimination, and calculated standardized mortality ratio (SMR) for estimation of prediction. Results : We collected 193 medical records but analyzed 190 events because three children died within 2 h of ICU admission. The variables of PIM2 correlated with survival, except for the presence of post-procedure and low risk. In PRISM III, there was a significant correlation for cardiovascular/neurologic signs, arterial blood gas analysis but not for biochemical and hematologic data. Discriminatory performance by ROC showed an area under the curve 0.858 (95% confidence interval; 0.779-0.938) for PIM2, 0.798 (95% CI; 0.686-0.891) for PRISM III, respectively. Further, SMR was calculated approximately as 1 for the 2 systems, and multiple logistic regression analysis showed ${\chi}^2(13)=14.986$, P=0.308 for PIM2, ${\chi}^2(13)=12.899$, P=0.456 for PRISM III in Hosmer-Lemeshow goodness-of-fit. However, PIM2 was significant for PRISM III in the likelihood ratio test (${\chi}^2(4)=55.3$, P<0.01). Conclusion : We identified two acceptable scoring systems (PRISM III, PIM2) for the prediction of mortality in children admitted into the ICU. PIM2 was more accurate and had a better fit than PRISM III on the model tested.

Prism Compressive Strength of Non-structural Concrete Brick Masonry Walls According to Workmanship (시공정밀도에 따른 비구조용 콘크리트벽돌 조적벽체의 프리즘 압축강도)

  • Shin, Dong-Hyeon;Kim, Hyung-Joon
    • Journal of the Architectural Institute of Korea Structure & Construction
    • /
    • v.36 no.2
    • /
    • pp.127-136
    • /
    • 2020
  • Prism compressive strength is the most influential parameter to evaluate the seismic performance of non-structural concrete brick masonry walls, and is affected by the practice and workmanship of masonry workers. This study experimentally investigates the influence of workmanship on prism compressive strength throughout the compressive test with prism specimens constructed according to masonry workmanship. To do this, the workmanship is categorized into good, fair, and poor conditions which are statistically evaluated with thickness and indentation depth of bed-joints. Then, the effect of workmanship on the structural properties of masonry prisms is evaluated by investigating relations between properties such as their compressive strength, elastic modulus and numerical parameters such as thickness, filling of bed-joints. This study demonstrates that the indentation depth is more important parameter for structural properties of masonry prisms and masonry prisms with loss in bed-joint area less than of 7% can be in fair condition.