• Title/Summary/Keyword: field testing

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Self-adaptive testing to determine sample size for flash memory solutions

  • Byun, Chul-Hoon;Jeon, Chang-Kyun;Lee, Taek;In, Hoh Peter
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.6
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    • pp.2139-2151
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    • 2014
  • Embedded system testing, especially long-term reliability testing, of flash memory solutions such as embedded multi-media card, secure digital card and solid-state drive involves strategic decision making related to test sample size to achieve high test coverage. The test sample size is the number of flash memory devices used in a test. Earlier, there were physical limitations on the testing period and the number of test devices that could be used. Hence, decisions regarding the sample size depended on the experience of human testers owing to the absence of well-defined standards. Moreover, a lack of understanding of the importance of the sample size resulted in field defects due to unexpected user scenarios. In worst cases, users finally detected these defects after several years. In this paper, we propose that a large number of potential field defects can be detected if an adequately large test sample size is used to target weak features during long-term reliability testing of flash memory solutions. In general, a larger test sample size yields better results. However, owing to the limited availability of physical resources, there is a limit on the test sample size that can be used. In this paper, we address this problem by proposing a self-adaptive reliability testing scheme to decide the sample size for effective long-term reliability testing.

An Improved Method for Screening Rice Cultivars with Field Resistance to Bacterial Leaf Blight (벼흰빛잎마름병에 대한 포장 저항성의 새로운 검정법)

  • Choi J. E.;Lee D. K.;Seo J. H.;Bae S. H.
    • Korean Journal Plant Pathology
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    • v.1 no.2
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    • pp.115-121
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    • 1985
  • To improve methods of screening rice cultivars with field resistance to bacterial leaf blight, testing plant inoculation and neighbor plant inoculation were compared by using 33 rice cultivars. In the testing plant inoculation method, field resistance was evaluated by measuring the leaf areas diseased on the new leaves expanded after the inoculation. Varietal differences in field resistance were recognized more clearly by the testing plant inoculation method than by the neighbor plant inoculation method. Highly significant correlation was observed between the results of the two methods. Some rice cultivars such as, Seomjin, Hangangchal, Taebaeg, Samgang, Milyang 42, Asominori, Java 14, Chugoku 45 and 70X-46 showed remarkable field resistance to bacterial leaf blight. The testing plant inoculation method appeared desirable for screening rice cultivars for the qualitative and field resistance to bacterial leaf blight because of using less labor and less field area than neighbor plant inoculation.

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Bridge load testing and rating: a case study through wireless sensing technology

  • Shoukry, Samir N.;Luo, Yan;Riad, Mourad Y.;William, Gergis W.
    • Smart Structures and Systems
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    • v.12 no.6
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    • pp.661-678
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    • 2013
  • In this paper, a wireless sensing system for structural field evaluation and rating of bridges is presented. The system uses a wireless platform integrated with traditional analogue sensors including strain gages and accelerometers along with the operating software. A wireless vehicle position indicator is developed using a tri-axial accelerometer node that is mounted on the test vehicle, and was used for identifying the moving truck position during load testing. The developed software is capable of calculating the theoretical bridge rating factors based on AASHTO Load and Resistance Factor Rating specifications, and automatically produces the field adjustment factor through load testing data. The sensing system along with its application in bridge deck rating was successfully demonstrated on the Evansville Bridge in West Virginia. A finite element model was conducted for the test bridge, and was used to calculate the load distribution factors of the bridge deck after verifying its results using field data. A confirmation field test was conducted on the same bridge and its results varied by only 3% from the first test. The proposed wireless sensing system proved to be a reliable tool that overcomes multiple drawbacks of conventional wired sensing platforms designed for structural load evaluation of bridges.

Characteristics of Behavior of the Soft Roadbed through Long-Term Instrumentation on the Field Test (운행선상의 연약노반 시험부설구간에서의 장기계측을 통한 거동 특성)

  • Lee Jin-Wook;Choi Chan-Yong;Lee Sung-Hyok;Lee Cnang-Youl
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1058-1064
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    • 2004
  • As one of reinforcing methods for soft roadbed, the problems that mud-pumping and settlement occurred by soft roadbed, were investigated, evaluated and analyzed through installing relatively economical and efficient geosynthetics on the selected track-bed for testing. Mock-heang to Dong-ryang on the filed resting sections in the Chung-buk lines were selected as investigating the state of track and prepared field after selecting three of 1,700 spots which often make mud-pumping and requiting maintenance for that. Long curved line radiuses(R) of Mock-heang to Dong-ryang are 500m that were installed with 4 types of geosynthetics layers and one ballast layer. Installed testing cross-section is 200m totally with 40 m between places. Strength or prepared roadbed was measured to investigate the state of roadbed and track with constructing(installing) field testing sections and physical properties of roadbed soils were evaluated and analyzed. Also, mud-pumping, settlement of elastic or plastic sleeper, failure or track, wheel-loads, transverse and earth pressures were measured after installing field testing sections.

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Time Domain Combined Field Integral Equation for Transient Electromagnetic Scattering from Dielectric Body (유전체의 전자기 과도산란 해석을 위한 시간영역 결합 적분방정식)

  • Kim Chung-Soo;An Hyun-Su;Park Jae-Kwon;Jung Baek-Ho
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.12
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    • pp.626-633
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    • 2004
  • In this paper, we present a time domain combined field integral equation (TD-CFIE) formulation to analyze the transient electromagnetic response from three-dimensional dielectric objects. The solution method in this paper is based on the method of moments (MoM) that involves separate spatial and temporal testing procedures. A set of the RWG (Rao, Wilton, Glisson) functions Is used for spatial expansion of the equivalent electric and magnetic current densities and a combination of RWG and its orthogonal component is used as spatial testing. We also investigate spatial testing procedures for the TD-CFIE to select the proper testing functions that are derived from the Laguerre polynomials. These basis functions are also used for temporal testing. Use of this temporal expansion function characterizing the time variable enables one to handle the time derivative terms in the integral equation and decouples the space-time continuum in an analytic fashion. Numerical results computed by the proposed formulation are presented and compared with the solutions of the frequency domain combined field integral equation (FD-CFIE).

Effect of thickness stretching and multi-field loading on the results of sandwich piezoelectric/piezomagnetic MEMS

  • Xiaoping Zou;Gongxing Yan;Wangming Wu;Wenjie Yang;Weiwei Shi;Yuhusun Sun
    • Steel and Composite Structures
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    • v.46 no.4
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    • pp.485-495
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    • 2023
  • Bending static and stress investigation of a microplate of piezoelectric/piezomagnetic material subjected to combined multifield loading. Shear deformable as well as thickness stretched model is used for derivation of the kinematic relations. Multi field governing equations are derived analytically through principle of virtual work. the results are analytically obtained analytically including magnetic/electric potentials, displacement and stress components with variation in multifield loading parameters.

Structural Performance of an Advanced Compsites Bridge Superstructure for Rapid Installation (급속시공용 복합신소재 교량상부구조의 구조 성능)

  • Ji, Hyo-Seon
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.1 no.1
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    • pp.34-45
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    • 2010
  • This paper describes the design, manufacturing process, testing, application, and assessment of capacity-ratings of the first all advanced composites bridge on a public highway system. In order to verify the bridge design prior to the field application, a sub-scale bridge superstructure was built and tested in the laboratory. The field load test results were compared with those of the finite element analysis for the verification of validity. To investigate its in-service performance, field load testing and visual inspections were conducted under an actual service environment. The paper includes the presentation and discussion for advanced composites bridge capacity rating based on the stress modification coefficients obtained from the test results. The test result indicates that the advanced composites bridge has no structural problems and is structurally performing well in-service as expected. Since these composite materials are new to bridge applications, reliable data is not available for their in-service performance. The results may provide a baseline data for future field advanced composites bridge capacity rating assessments and also serve as part of a long-term performance of advanced composites bridge.

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Sources of uniform and 2nd-order gradient fields for testing SQUID performance (SQUID 2차미분기 성능 평가용 균일자기장 및 2차 미분 자기장 발생원)

  • Lee, Soon-Gul
    • Progress in Superconductivity
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    • v.8 no.2
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    • pp.152-157
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    • 2007
  • Uniaxial square Helmholtz coils for testing SQUID sensors were designed and their field distributions were calculated. Optimum parameters for maximizing the uniform region in the Helmholtz mode were obtained for different uniformity tolerances. The coil system consists of 2 pairs of identical square loops, a Helmholtz pair for generating uniform fields and the other for the 2nd-order gradient fields in combination with the Helmholtz pair. Full expressions of the axial component of the field were calculated by using Biot-Savart's law. To understand the behavior of the field near the coil center, analytical expressions were obtained up to the 4th-order in the midplane and along the coil axis. The Helmholtz condition for generating uniform fields was calculated to be $d/{\alpha}=0.544505643$, where 2d is the inter-coil distance and $2{\alpha}$ is the side length of the coil square. Maximized uniform range can be obtained for a given nonuniformity tolerance by choosing $d/{\alpha}$ slightly lower than the Helmholtz condition. The pure second-order gradient field can be generated by subtracting the Helmholtz field from the field of the 2nd pair with equal magnitudes of the center fields of the two pairs. The coil system is useful for testing balance and sensitivity of SQUID gradiometers.

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Field Testing of High-Speed Power Line Communications (고속 전력선통신의 현장성능 분석)

  • Kim, Sang-Jo;Lee, Byung-Gu;Kim, Geun-Young;Kim, Sok-Ho
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.227-230
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    • 2009
  • In this paper, the results of field testing of high-speed power line in-home networking in Korea are reported. When multiple networks share a common channel, they can interfere destructively and reduce system capacity. This is major problem in-home power line communications, especially in MDU deployments. The effects of neighboring network interference in power line communications are reported.

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Real-Time System Parallel Testing Techniques for Weapon System Error Verification (무기체계 오류 검증을 위한 실시간 시스템 병렬시험 기법)

  • Kim, Dong-Jun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.11
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    • pp.130-138
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    • 2016
  • In this paper present the real-time system parallel testing techniques for weapon systems error verification. Previously field testing equipment in the military field was using the sequential testing method to maintain. This method could not check the error verification of interference. For this reason, in this paper propose the real-time system parallel testing techniques using an embedded module instead of the sequential testing techniques which is used in the weapon system error verification. Using the embedded module mounted switching control card conduct the parallel testing and then send the result to the PC. This method is possible to increase the reliability in the weapon system error verification.