• Title/Summary/Keyword: Designed-to-fail

Search Result 138, Processing Time 0.021 seconds

A Study on the precious stopping control for the automatic electric rail cars (도시철도 전차의 정위치 정차 제어에 관한 연구)

  • Park, Mun-Gyu;Kim, Gyu-Sik
    • Proceedings of the KIEE Conference
    • /
    • 2006.04a
    • /
    • pp.228-230
    • /
    • 2006
  • While trains perform a complete precision stopping control at stop point, it is essential to keep better commuters comfort in prompt. Because a train's brake force tends to increase a brake effort in a low speed and a low brake effort, a brake force in motor cars must be increased to keep better passenger comfort, to control the special braking qua1ities and to prevent the impact of the automatic coupler rather than trailer's, Rail cars must have a special braking process for the train stopping control. In the train stop mode, the train stopping control is designed to start at 20km/h. It starts by Dynamic brake blending, and then finally stops by only the friction. If these process are not exactly activated, the train may fail a complete precision stop. In this report, it studied the electric and friction brake processing during the precious stopping control. To achieve exact test results, the speed reference has to be reduced the calculated difference. In the precision stopping control. the ways of the keeping brake force in motor car was analyzed and some solutions of controling air pressure was brought up by means of direct test in main line, This study was based on line 5 in Seoul Metropolitan subway.

  • PDF

A Relationship of Tone, Consonant, and Speech Perception in Audiological Diagnosis

  • Han, Woo-Jae;Allen, Jont B.
    • The Journal of the Acoustical Society of Korea
    • /
    • v.31 no.5
    • /
    • pp.298-308
    • /
    • 2012
  • This study was designed to examine the phoneme recognition errors of hearing-impaired (HI) listeners on a consonant-by-consonant basis, to show (1) how each HI ear perceives individual consonants differently and (2) how standard clinical measurements (i.e., using a tone and word) fail to predict these differences. Sixteen English consonant-vowel (CV) syllables of six signal-to-noise ratios in speech-weighted noise were presented at the most comfortable level for ears with mild-to-moderate sensorineural hearing loss. The findings were as follows: (1) individual HI listeners with a symmetrical pure-tone threshold showed different consonant-loss profiles (CLPs) (i.e., over a set of the 16 English consonants, the likelihood of misperceiving each consonant) in right and left ears. (2) A similar result was found across subjects. Paired ears of different HI individuals with identical pure-tone threshold presented different CLPs in one ear to the other. (3) Paired HI ears having the same averaged consonant score demonstrated completely different CLPs. We conclude that the standard clinical measurements are limited in their ability to predict the extent to which speech perception is degraded in HI ears, and thus they are a necessary, but not a sufficient measurement for HI speech perception. This suggests that the CV measurement would be a useful clinical tool.

Analysis of Vibration Noise Spectrum in Motor-Driven Power Steering System (Motor-Driven Power Steering 시스템의 진동 소음 스펙트럼 분석)

  • Park, Han Young;Kim, Jin Young;Kang, Joonhee
    • Journal of Sensor Science and Technology
    • /
    • v.27 no.2
    • /
    • pp.126-131
    • /
    • 2018
  • Unlike the hydraulic power steering (HPS) system, which operates by the high pressure of a fluid obtained from the engine power, the motor-driven power steering (MDPS) system uses an electric motor to steer the wheel without consuming engine power. To steer the wheel with an electric motor, a worm wheel and a worm gear rotating between the steering shaft and motor are required. Any imperfection during the construction of an MDPS system or in a composing part creates noise and vibration, which can be sensed by a driver. To solve the noise and vibration problems, each part must be designed to not resonate with other parts. In this work, we developed the measurement and analysis systems to obtain the noise and the vibration of an automobile MDPS system. A signal analyzer was equipped with a 96 kHz, 24-bit ADC and a 150 MHz digital signal processor. The predetermined threshold value of the vibration in the MDPS system was used to determine the pass/fail, and the results were displayed on the screen. Our system can be used in the fabrication line to swiftly determine any imperfections in the MDPS system construction.

Design of a High Efficiency Neon Transformer with Abnormal Load Interrupting Circuit (부하측 이상 검출 차단 장치를 내장한 고효율 자기식 네온 변압기의 설계)

  • Byun Jei-Young;Kim Yoon-Ho
    • Proceedings of the KIPE Conference
    • /
    • 2002.07a
    • /
    • pp.723-726
    • /
    • 2002
  • In this paper, a high efficiency leakage transformer for neon tube is developed to improve its power factor, to reduce its core loss and weight by using a technique of shape optimization and direction of grain-oriented silicon steel sheet. A protection circuit is designed for all types of neon transformer loaded with one or more neon lamps. Whenever the neon tube fails to be started up or comes to the life end, or encounters faults with open-circuits at the output terminals of the neon transformer, the protection circuit will be initiated to avoid more critical hazards. These neon transformers need a protection circuit to prevent from current stresses on circuit components by neon tube fail. The input of the transformer is automatically cut off when the abnormal condition occurs, preventing waste of no-load power. As the results of the study, the core weight is reduced by $11\%$, the power factor improved by $5\%$ and the efficiency increased by $6\%$ compared with the conventional type due to the employment of the grain-oriented steel sl)eel and the optimized core shape.

  • PDF

A Study on the Development of Library Space Planning Major Based on the Self-Designed Major (자기설계전공기반 도서관공간기획전공 개발에 관한 연구)

  • Noh, Younghee;Shin, Youngji
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.53 no.1
    • /
    • pp.5-31
    • /
    • 2019
  • In this study, in order to foster human resources equipped with expertise in libraries and spatial organization that contributes to the development of libraries, planning, design, and construction, the self-designed library space planning major was developed and the education goal, human resources award, and major capabilities were presented. To this end, the relevant literature analysis, expert opinion collection, and consumer survey were conducted, and the results are as follows. First, the person-in-person awards required for library space planning were identified as space planning personnel, design thinking personnel, and creative working people. Second, the person-specific majors were derived with the ability to analyze the library environment, ability to express spatial concepts, ability to analyze user needs, ability to coordinate interests, ability to understand spatial design, ability to understand spatial design, and ability to apply practical applications. Based on the plan, subjects should be developed that can fulfill the educational goals of the future library space planning major, human resources award, and human resources status, and operation plans should be designed so that the library space planning major can adapt students without fail due to its own design-based major.

Barriers on Development of Clinical Practice Guidelines for Cardiopulmonary Resuscitation (임상진료지침 개발과정의 장애요인 - 심폐소생술을 중심으로 -)

  • Park, Seong-Hi
    • Quality Improvement in Health Care
    • /
    • v.7 no.1
    • /
    • pp.46-58
    • /
    • 2000
  • Background : Despite favorable effects of guidelines on patient care, guidelines often fail to achieve their objectives. Poorly implemented medical practice guidelines can produce only weak effects on the process of health care delivery. Therefore, we performed this study to investigate barriers related development of clinical practice guidelines. Methods : Cardiopulmonary resuscitation was selected as a target problem. Self questionnaires about management of cardiopulmonary resuscitation were developed by a researcher with advisory 8 experts. The questionnaires were designed as a unstructured methods. The data were collected from March 1 to May 31, 1999. A total 50 death case admitted inpatient to Inha University Hospital were subjected to evaluate the development and application of clinical practice guidelines for cardiopulmonary resuscitation. The data were examined by frequency, t-test with SPSS. Result : The article reviewed several common barriers that might limit successful implementation of guidelines in clinical practice, as illustrated by evaluating recommendations for cardiopulmonary resuscitation clinical practice guidelines. Some major problems with guidelines were characterized as follows (1) ethical problem : euthanasia, (2) occurrence on various emergency event and setting, (3) non-medical problems (4) unreliable of medical record etc. Conclusion : Careful analysis of guideline attributes, anticipated effect on medical care, and organizational factors revealed several barriers to successful guideline implementation that should be addressed in the design of future guideline-based interventions.

  • PDF

A Development of Administrative Affairs Supporting System using Call Control Mode of CTI (CTI 호출 제어 방식을 이용한 행정 업무 지원 시스템의 개발)

  • 최준기;조성범;정상수;이상정
    • Journal of the Korea Society of Computer and Information
    • /
    • v.4 no.2
    • /
    • pp.46-60
    • /
    • 1999
  • Recently, CTI (Computer Telephony Integration) technology has been widely applied to various area such as video conference, file transfer, voice mail, automatic message transfer and automatic redial, integrated messaging and network fax. In this paper, an administrative affairs supporting system using call control mode of CTI is designed. To improve inefficient processing of job due to heavy calling from entrance candidates during entrance examination of a college, the system is developed. The database of the system is desigend using object modeling technique. Also, the automatic calling and response system using CTI call control mode is implemented. Especially, to interface with voice of candidates who ask whether they pass or fail the entrance examination of the college, TTS(Text To Speech) module is developed.

  • PDF

Analysing the Combined Kerberos Timed Authentication Protocol and Frequent Key Renewal Using CSP and Rank Functions

  • Kirsal-Ever, Yoney;Eneh, Agozie;Gemikonakli, Orhan;Mostarda, Leonardo
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.8 no.12
    • /
    • pp.4604-4623
    • /
    • 2014
  • Authentication mechanisms coupled with strong encryption techniques are used for network security purposes; however, given sufficient time, well-equipped intruders are successful for compromising system security. The authentication protocols often fail when they are analysed critically. Formal approaches have emerged to analyse protocol failures. In this study, Communicating Sequential Processes (CSP) which is an abstract language designed especially for the description of communication patterns is employed. Rank functions are also used for verification and analysis which are helpful to establish that some critical information is not available to the intruder. In order to establish this, by assigning a value or rank to each critical information, it is shown that all the critical information that can be generated within the network have a particular characterizing property. This paper presents an application of rank functions approach to an authentication protocol that combines delaying the decryption process with timed authentication while keys are dynamically renewed under pseudo-secure situations. The analysis and verification of authentication properties and results are presented and discussed.

VEHICLE CRASH ANALYSIS FOR AIRBAG DEPLOYMENT DECISION

  • Hussain, A.;Hannan, M.A.;Mohamed, A.;Sanusi, H.;Ariffin, A.K.
    • International Journal of Automotive Technology
    • /
    • v.7 no.2
    • /
    • pp.179-185
    • /
    • 2006
  • Airbag deployment has been responsible for huge death, incidental injuries and broken bones due to low crash severity and wrong deployment decision. This misfortune has led the authorities and the industries to pursue uniquely designed airbags incorporating crash-sensing technologies. This paper provides a thorough discussion underlying crash sensing algorithm approaches for the subject matter. Unfortunately, most algorithms used for crash sensing still have some problems. They either deploy at low severity or fail to trigger the airbag on time. In this work, the crash-sensing algorithm is studied by analyzing the data obtained from the variables such as (i) change of velocity, (ii) speed of the vehicle and (iii) acceleration. The change of velocity is used to detect crash while speed of the vehicle provides relevant information for deployment decision. This paper also demonstrates crash severity with respect to the changing speed of the vehicle. Crash sensing simulations were carried out using Simulink, Stateflow, SimMechanics and Virtual Reality toolboxes. These toolboxes are also used to validate the results obtained from the simulated experiments of crash sensing, airbag deployment decision and its crash severity detection of the proposed system.

Shear strengthening of deficient concrete beams with marine grade aluminium alloy plates

  • Abu-Obeidah, Adi S.;Abdalla, Jamal A.;Hawileh, Rami A.
    • Advances in concrete construction
    • /
    • v.7 no.4
    • /
    • pp.249-262
    • /
    • 2019
  • In this study, high strength aluminum alloys (AA) plates are proposed as a new construction material for strengthening reinforced concrete (RC) beams. The purpose of this investigation is to evaluate AA plate's suitability as externally bonded reinforcing (EBR) materials for retrofitting shear deficient beams. A total of twenty RC beams designed to fail in shear were strengthened with different spacing and orientations. The specimens were loaded with four-points loading till failure. The considered outcome parameters included load carrying capacity, deflection, strain in plates, and failure modes. The results of all tested beams showed an increase up to 37% in the load carrying capacity and also an increase in deflection compared to the control un-strengthened beams. This demonstrated the potential of adopting AA plates as EBR material. Finally, the shear contribution from the AA plates was predicted using the models available in the ACI440-08, TR55 and FIB14 design code for fiber reinforced polymer (FRP) plates. The predicted results were compared to experimental testing data with the ratio of the experimentally measured ultimate load to predicted load, range on the average, between 93% and 97%.