• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.3
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• pp.300-311
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• 2016

The analog-to-digital-converter-based (ADC-based) backplane receivers that consist of a front-end ADC followed by a digital equalizer are gaining more popularity in recent years, as they support more sophisticated equalization required for high data rates, scale better with fabrication technology, and are more immune to PVT variations. Unfortunately, designing an ADC-based receiver that meets tight power and performance budgets of high-speed backplane link systems is non-trivial as both front-end ADC and digital equalizer can be power consuming and complex when running at high speed. This paper reviews the state of art designs for the front-end ADC and digital equalizers to suggest implementation choices that can achieve high speed while maintaining low power consumption and complexity. Design-space exploration using system-level models of the ADC-based receiver allows through analysis on the impact of design parameters, providing useful information in optimizing the power and performance of the receiver at the early stage of design. The system-level simulation results with newer device parameters reveal that, although the power consumption of the ADC-based receiver may not comparable to the receivers with analog equalizers yet, they will become more attractive as the fabrication technology continues to scale as power consumption of digital equalizer scales well with process.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.104-110
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• 2009

In this driving simulation study, the impairing effects of various types of electronic devices usage(i. e., destination search by using in-vehicle navigation system, TV watching and dialing cellular phone) during driving on front-to-rear-end collision avoidance were investigated. Percentage of collisions, driving speeds when the drivers collided, and initial reaction time for collision avoidance were analyzed and compared as the dependent measures. The results indicated that (1) any types of electronic devices usage during driving induced more serious collision-related impairment than control condition where no additional task was required, and (2) in general, destination search task appeared to impair drivers collision avoidance performance more than the other task requirements in terms of percentage of collisions and initial reaction time for collision avoidance, but TV watching induced most serious collision impact. These results suggested that any types of electronic device usage could distract drivers attention from the primary task of driving, and be resulted in serious outcome in potentially risky situation of front-to-rear-end collision. In particular, mandatory use of eye-hand coordination and receiving feedback seemed to one of essential factor leading the drivers visual attentional distraction.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.217-224
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• 2021

Objective: This study is about the physical therapy facilities and environmental and service satisfaction of patients visiting in the front military hospitals and divisions. Design: Survey study Methods: Prior to this survey, 28 users of the front division and military hospital were surveyed in advance to verify the survey through reliability analysis. For this survey, 1,300 questionnaires were distributed to seven frontline divisions and three military hospitals, of which 578 military hospitals and 479 divisions were collected. Among them, 1,042 pieces of data were used for the analysis, excluding 15 questionnaires that exceeded the research period of the division. Analysis methods used Cronbach-α and multiple regression for mean comparison analysis, factor analysis for validation, and reliability verification to verify differences between groups. Results: As a result of the satisfaction analysis, the division's stage satisfaction was higher than that of military hospitals, and as a result of analyzing the satisfaction items by sector, accessibility, re-visit doctors, and professionalism accounted for a large portion in the field of physical therapy services. As a result of a regression analysis, the factors that affect the satisfaction of physical therapy had the greatest impact on facility and environmental satisfaction, and expertise in physical therapy services. Conclusions: In the future, it will be necessary to improve the comfort of the physical therapy room and the expertise of physical therapy in order to improve the satisfaction level of physical therapy at military medical facilities.

• Journal of Auto-vehicle Safety Association
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• v.9 no.1
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• pp.13-18
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• 2017

In recent years, NCAP regulations of many countries have induced automaker to improve the vehicle crashworthiness. But, the current NCAP regulations don't cover all types of traffic accidents. And rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility. So, many countries have tried to develop the new crash test mode and update the present crash test mode. Especially, Euro NCAP has been developing a new impact protocol of the car-to-car frontal offset impact including the crash compatibility assessment. There are plans to introduce this new protocol in 2020, and it will be replaced the current Euro NCAP frontal offset impact. The test dummy in the front seats of this new test mode will be changed from 50% Hybrid-III male to 50% THOR male. This paper will address the vehicle responses, the occupant responses and the vehicle compatibility performance from a full vehicle crash test using the new car-to-car frontal offset test protocol of Euro NCAP.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.4
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• pp.338-347
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• 2010

Heunginjimun designated as a Treasure No.1 is a two-story wooden structure with 5 bay and 2 bay in its front and side views, respectively. This paper presents an investigation on vibration characteristics of Heunginjimun through both ambient vibration and impact hammer tests. Ambient vibration test was performed to identify the natural frequency of Heunginjimun from the spectrum analysis of time history. Impact hammer test was undertaken to find the frequency of Heunginjimun which is affected by the surrounding traffics and to verify the reciprocal principle for the wooden structural system. Ambient vibration test results of Heunginjimun showed that the natural frequencies in two principal axes 1.5 Hz and 1.1 Hz, respectively. It was confirmed from impact hammer tests for a ground that the frequency of 4.2 Hz is caused by the traffics surrounding Heunginjimun. It was also observed that from the impact hammer test results between two locations in Heunginjimun that the transfer functions measured from two corresponding locations coincided well with each other. This result shows that the wooden structural system is globally linear, and the reciprocal principle is established.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.134-139
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• 2003

The car crash accidents in low speed occurs most frequently. Damage on a conventional bumper after the car accident causes the bumper to get fixed most of time. This study shows how a gas tube bumper reduces a damageability and increase repairability after the car accidents. The 15 km/h 40% offset front and rear crash test recommended by RCAR (Research council for automobile repairs) standard was performed and evaluated damages on the gas tube bumper by the pendulum impact tester. In this study, the gas tube bumper reduces damageability and increases repairability after car crash accidents. In addition, car frame design to apply the gas tube bumper may consider to be changed.

• Journal of the Korean Society for Railway
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• v.1 no.1 s.1
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• pp.1-9
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• 1998

Described in this paper is the result of a study on collision analysis of TGV-K using 1-dimensional model for crashworthy design. Crashworthy design of the front end is very important because majority of the impact energy (more than 70%) is absorbed by the crush of the front end when the train is collided with an obstacle like a tank lorry. Guideline for the crashworthy design can be described from the collision analysis of the whole train using a 1-dimensional model. Since the headstock of TGV-K is not designed in a crashworthy point of view, a conceptual design of the headstock to improve crashworthiness is suggested and evaluated using 1-dimensional collision analysis. The suggested design, which adopts an energy absorber and a crashworthy headstock, shows a good behaviour on the accident scenario of SNCF (collision at 110 km/h against a movable rigid mass of 15 ton).

• Proceedings of the KSR Conference
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• 1998.05a
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• pp.361-368
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• 1998

Described in this paper is the result of a study on collision analysis of TGV-K using 1-dimensional model for crashworthy design. Crashworthy design of the front end is very important because majority of the impact energy (more than 70%) is absorbed by the crush of the front end when the train is collided with an obstacle like a tank lorry. Guideline for the crashworthy design can be described from the collision analysis of the whole train using a 1-dimensional model. Since the headstock of TGV-K is not designed in a crashworthy point of view, a conceptual design of the headstock to improve crashworthiness is suggested and evaluated using 1-dimensional collision analysis. The suggested design, which adopts an energy absorber and a crashworthy headstock, shows a good behaviour on the accident scenario of SNCF (collision at 110 km/hr against a movable rigid mass of 15 ton).

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.3
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• pp.163-170
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• 2000

Accident statistics shows that the portion of fatal occupant injuries due to side impacts is considerably high. The side impact usually leads to a severe intrusion of side structure into the passenger compartment. Furthermore, the safety zone for the side impact is relatively small compared to the front impact. Those kinds of physics for side impact frequently result in a fatal injury for the occupant. Therefore, NHTSA and EEVC are trying to intensify the regulation for the occupant protection against side impact. Both the regulation and recent market trends are asking for an installation of side airbag. There are several types of system configuration for side impact sensing. In this paper, we adopt the acceleration-based remote sensing method for the side airbag control system. We mainly focus on the development of hardware and crash discrimination algorithm of remote sensing unit. The crash discrimination algorithm needs fast decision of airbag firing especially for high-speed side impact such as FMVSS 214 and EEVC tests. It is also required to distinguish between low-speed fire and no-fire events. The algorithm should have a sufficient safety margin against any misuse situation such as hammer blow, door slam, etc. This paper introduces several firing criteria such as acceleration. velocity and energy criteria that use physical value proportional to crash severity. We have made a simulation program by using Matlab/Simulink to implement the proposed algorithm. We have conducted an algorithm calibration by using real crash data for 2,500cc vehicle. The crash performance obtained by the simulation was verified through a pulse injection method. It turned out that the results satisfied the system requirements well.

• Journal of Mechanical Science and Technology
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• v.18 no.6
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• pp.924-932
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• 2004

In this study, the axial collapse tests were performed under either static (or quasi-static) or impact loads with several collapse velocities based on the expectation that para-closed sections of the front-end side members (spot welded hat and double hat shaped section members) would show quite different collapse characteristics from those for seamless section. The test results showed that both of the hat and double hat shaped section members failed in the stable sequential collapse mode in the static or quasi-static collapse tests, while the double hat shaped section members underwent the unstable collapse mode especially when the impact velocity is high. The mean collapse loads in the hat shaped section members increase with collapse velocity for all the cases of the static, quasi-static, and impact collapse tests. In the double hat shaped section members, however, the mean collapse loads decrease with increase in collapse velocity in the impact tests.