• Title/Summary/Keyword: Robustness test

Search Result 342, Processing Time 0.025 seconds

Tests of Hypotheses in Multiple Samples based on Penalized Disparities

  • Park, Chanseok;Ayanendranath Basu;Ian R. Harris
    • Journal of the Korean Statistical Society
    • /
    • v.30 no.3
    • /
    • pp.347-366
    • /
    • 2001
  • Robust analogues of the likelihood ratio test are considered for testing of hypotheses involving multiple discrete distributions. The test statistics are generalizations of the Hellinger deviance test of Simpson(1989) and disparity tests of Lindsay(1994), obtained by looking at a 'penalized' version of the distances; harris and Basu (1994) suggest that the penalty be based on reweighting the empty cells. The results show that often the tests based on the ordinary and penalized distances enjoy better robustness properties than the likelihood ratio test. Also, the tests based on the penalized distances are improvements over those based on the ordinary distances in that they are much closer to the likelihood ratio tests at the null and their convergence to the x$^2$ distribution appears to be dramatically faster; extensive simulation results show that the improvement in performance of the tests due to the penalty is often substantial in small samples.

  • PDF

CONTROL PHILOSOPHY AND ROBUSTNESS OF ELECTRONIC STABILITY PROGRAM FOR THE ENHANCEMENT OF VEHICLE STABILITY

  • Kim, D.S.;Hwang, I.Y.
    • International Journal of Automotive Technology
    • /
    • v.7 no.2
    • /
    • pp.201-208
    • /
    • 2006
  • This paper describes the control philosophy of ESP(Electronic Stability Program) which consists of the stability control the fault diagnosis and the fault tolerant control. Besides the functional performance of the stability control, robustness of control and fault diagnosis is focused to avoid the unnecessary activation of the controller. The look-up tables are mentioned to have the accurate target yaw rate of the vehicle and obtained from vehicle tests for the whole operation range of the steering wheel angle and the vehicle speed. The wheel slip control with a design goal of wheel slip invariance is implemented for the yaw compensation and the target wheel slip is determined by difference between the target yaw rate and actual yaw rate. Since the ESP has a high severity level and the robust control is required, the robustness margin for the stability control is determined according to several uncertainties and the robust fault diagnosis is performed. Both computer simulation and test results are shown in this paper.

Does Individual's Income always Matter Happiness?: Evidence from China

  • HE, Yugang;WU, Renhong
    • Journal of Wellbeing Management and Applied Psychology
    • /
    • v.3 no.1
    • /
    • pp.21-31
    • /
    • 2020
  • As people's income rises dramatically, people's happiness seems not as high as expected. In fact, there are two different arguments about the relationship between income level and happiness. The focus of the debate is whether the correlation between income and probability of happiness is positive or negative. Therefore, we hypothesizes that the relationship between income and probability of happiness presents an inverted U-shaped curve. Then, this paper sets China as an example to explore the effect of income on happiness. The data from the Chinese General Social Survey (CGSS) in 2015 is employed to conduct empirical analyses under the Probit model and the Zero-Inflation-Passion model. The empirical findings indicate that the effect of income on happiness presents an inverted U-shaped curve and significantly in statistic. Meanwhile, spouse's income, educational level, marriage time and house property have a positive and significant effect on happiness. Conversely, age and local living standards have a negative and significant effect on happiness. Unfortunately, even though registered residence and children have a negative effect on happiness, they do not get through the significant test. In order to ensure the robustness of our empirical results, we test the robustness of the above empirical results by adjusting the sample size. The results of robustness test verify that our empirical results are robust. Moreover, this paper also makes a small contribution to the current literature with a sample from China.

The Study of Low Extremity Injury under Small Overlap Crash Test (스몰오버랩 충돌 시 하지상해 발생 메커니즘 규명)

  • Kim, Hyun Chul;Nam, Yun Sik;Kim, Byoung Chul;Kim, Ki Il;Kim, Ki Sung
    • Journal of Auto-vehicle Safety Association
    • /
    • v.9 no.1
    • /
    • pp.25-31
    • /
    • 2017
  • Small Overlap test decided on IIHS (Insurance Institute for Highway Safety) evaluates a robustness of the car body and a passenger injury protection. A current vehicle is satisfied with a robustness of the car body for Small Overlap test but not meet the requirements of passenger injuries because it is difficult to inquire into the actual state of injury mechanism for Small Overlap test. The study shows the new injury mechanism which represents the relation between a structure of the vehicle placed with the lift foot and the low extremity injury.

Breakdown Points of Direction Tests

  • Park, Kyung-Mee
    • Journal of the Korean Statistical Society
    • /
    • v.26 no.2
    • /
    • pp.211-222
    • /
    • 1997
  • We briefly review three Raleigh type location tests based on direction vectors, which have been shown to be efficient when the distribution is unknown, skewed, or heavy-tailed. Then we calculate their test breakdown points and discuss the robustness of Randles multivariate sign test for one-sample.

  • PDF

On-Machine Measurement of an Optical Surface by Hartmann Test (하트만 방법에 의한 광학면의 기상측정)

  • 김용관;오창진;이응석;김옥현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2002.10a
    • /
    • pp.474-480
    • /
    • 2002
  • Aspheric optical lenses and mirrors are widely used in recent. It is more difficult to manufacture and measure the aspherical optics compared to conventional spherical ones. The interferometric optical test is common for the measurement of spherical optical surface. But the application of the interferometry to the measurement of aspheric surface is difficult because it needs a precise null corrector and very careful environmental conditions such as keeping constant temperature, humidity, atmospheric pressure and vibrations. To enhance productivity of optics manufacturing on-machine measurement and correction has been developed in this study. For practical applications, robustness of the measurement method to environments is more important. For the purpose an optical OMM(On-Machine Measurement) system has been developed using Shack-Hartmann test which has robustness to the environment. The wavefront has been reconstructed from the measured data using the primary aberration polynomial function by least square fitting. The measured result of the developed only system gives the maximum deviation only in 200 nm from the result measured by a commercial Fizeau interferometer Wyko 6000.

  • PDF

A Study on the Structural Integrity Assessment of the Output Housing in Transmissions of a Tracked Vehicle (궤도차량 변속기 출력 하우징의 구조건전성 평가에 대한 연구)

  • Jung, Jae-Woong;Lee, Hee-Won;Moon, Tae-Sang;Gwon, Jun-Sik
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.18 no.1
    • /
    • pp.8-14
    • /
    • 2015
  • Transmission of a tracked vehicle designed for multiple functions such as steering, gear-shifting, and braking is a core component of heavy vehicle to which the power is transferred based on combined technology of various gears, bearing, and fluid machineries. Robustness and durability of transmission, however, have been issued due to a large number of driving units and sub-components inside its body. Particularly, transmission housing is important structure which supports the transmission, and is made of aluminum alloy. Thus, structural robustness against such mechanical loading or vibration must be attained. Structural reliability evaluation through FEM analysis can save time and cost of the actual tests. In this study, structural evaluation is conducted on output housing of transmission, which is core component of tracked vehicle, using the simulation program. In addition, transmission dynamo test is performed to evaluate structural robustness of the output housing against the vibration which can be produced during the transmission operation.

A Robustness Test Method and Test Framework for the Services Composition in the Service Oriented Architecture (SOA에서 서비스 조합의 강건성 테스트 방법 및 테스트 프레임워크)

  • Kuk, Seung-Hak;Kim, Hyeon-Soo
    • Journal of KIISE:Software and Applications
    • /
    • v.36 no.10
    • /
    • pp.800-815
    • /
    • 2009
  • Recently, Web services based service-oriented architecture is widely used to integrate effectively various applications distributed on the networks. In the service-oriented architecture BPEL as a standard modeling language for the business processes provides the way to integrate various services provided by applications. Over the past few years, some types of studies have been made on testing compatibility of services and on discriminating and tracing of the business processes in the services composition. Now a lot of studies about the services composition with BPEL are going on. However there were few efforts to solve the problems caused by the services composition. Especially, there is no effort to evaluate whether a composite service is reliable and whether it is robust against to exceptional situations. In this paper, we suggest a test framework and a testing method for robustness of the composite service written in WS-BPEL. For this, firstly we extract some information from the BPEL process and the participant services. Next, with the extracted information we construct the virtual testing environment that generates various faults and exceptional cases which may be raised within the real services. Finally the testing work for robustness of a composite service is performed on the test framework.

New GGNMOS I/O Cell Array for Improved Electrical Overstress Robustness

  • Pang, Yon-Sup;Kim, Youngju
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.13 no.1
    • /
    • pp.65-70
    • /
    • 2013
  • A 0.18-${\mu}m$ 3.3 V grounded-gate NMOS (GGNMOS) I/O cell array for timing controller (TCON) application is proposed for improving electrical overstress (EOS) robustness. The improved cell array consists of 20 GGNMOS, 4 inserted well taps, 2 end-well taps and shallow trench isolation (STI). Technology computer-aided design (TCAD) simulation results show that the inserted well taps and extended drain contact gate spacing (DCGS) is effective in preventing EOS failure, e.g. local burnout. Thermodynamic models for device simulation enable us to obtain lattice temperature distributions inside the cells. The peak value of the maximum lattice temperature in the improved GGNMOS cell array is lower than that in a conventional GGNMOS cell array. The inserted well taps also improve the uniformity of turn-on of GGNMOS cells. EOS test results show the validity of the simulation results on improvement of EOS robustness of the new GGNMOS I/O cell array.

Long term monitoring of a cable stayed bridge using DuraMote

  • Torbol, Marco;Kim, Sehwan;Shinozuka, Masanobu
    • Smart Structures and Systems
    • /
    • v.11 no.5
    • /
    • pp.453-476
    • /
    • 2013
  • DuraMote is a remote sensing system developed for the "NIST TIP project: next generation SCADA for prevention and mitigation of water system infrastructure disaster". It is designed for supervisory control and data acquisition (SCADA) of ruptures in water pipes. Micro-electro mechanical (MEMS) accelerometers, which record the vibration of the pipe wall, are used detect the ruptures. However, the performance of Duramote cannot be verified directly on a water distribution system because it lacks an acceptable recordable level of ambient vibration. Instead, a long-span cable-stayed bridge is an ideal test-bed to validate the accuracy, the reliability, and the robustness of DuraMote because the bridge has an acceptable level of ambient vibration. The acceleration data recorded on the bridge were used to identify the modal properties of the structure and to verify the performance of DuraMote. During the test period, the bridge was subjected to heavy rain, wind, and a typhoon but the system demonstrates its robustness and durability.