• Journal of Information Processing Systems
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• 제2권1호
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• pp.1-5
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• 2006

Finding a valid timing constraint is one of the most important issues in the real-time monitoring area. To get the valid timing constraint, a developer executes a real-time process and changes the constraint on a regular basis. This is an exhaustive and time-consuming process. To improve this approach, we propose a timing constraint search technique. This technique uses two load models and one condition proposed in this paper to support the developer in determining the valid timing constraint range in an easy and systematic manner.

• 소성∙가공
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• 제15권7호
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• pp.496-503
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• 2006

The inner and outer car panels for bonnet, door, and trunk lid are assembled by hemming rather than welding. To achieve successful fabrication of these panels, the complicated timing chart of hemming units for pre-and main hemming stages should be made to optimal one. In this study, a design system for automatic timing chart generation is developed. Using AutoCAD VBA and EXCEL data chart, hemming die design parameters and guidelines were put into the program to give hemming unit drawings and consequent timing charts. Then the prepared timing charts were checked and modified. The effectiveness of the system is verified by applying it successfully to hemming unit design for bonnet panel joining.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.973-976
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• 2004

So far, this report is written by knowledge and standard through several reference drawing and experienced contents with drawing hemming die. The contents about actual design is so huge that I will write about it next time. Timing chart is important to hemming die because of link position and numbers. Timing chart need a very much design time because link number and position have to applied for each case. In this paper developed an automatic timing chart and link position by relation and Pro/Program of Pro/Engineer. The method used relation rule of design parameter for timing chart. In the future, I believe that simple easy to correct and reasonable price hemming die will be producted.

• Journal of Advanced Marine Engineering and Technology
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• 제32권7호
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• pp.1013-1018
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• 2008

For a sequential port fuel injection natural gas engine, its combustion and emission characteristics at low loads are crucial to meet light duty vehicle emission regulations. Fuel injection timing is an important parameter related to the mixture formation in the cylinder. Its effect on the combustion and emission characteristics of a natural gas engine were investigated at 0.2 MPa brake mean effective pressure (BMEP)/2000 rpm and 0.26 MPa BMEP/1500 rpm. The results show that early fuel injection timing is beneficial to the reduction of the coefficient of variation (COV) of indicated mean effective pressure (IMEP) under lean burn conditions and to extending the lean burn limits at the given loads. When relative air/fuel ratio is over 1.3, fuel injection timing has a relatively large effect on engine.out emissions. The levels of NOx emissions are more sensitive to the fuel injection timing at 0.26 MPa BMEP/1500 rpm. An early fuel injection timing under lean burn conditions can be used to control engine out NOx emissions.

• 방송공학회논문지
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• 제24권7호
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• pp.1259-1265
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• 2019

Maintaining timing relationships among packets in a single media stream or between packets from different media streams is an essential criterion in MMT system. It is the function of the synchronization and de-jittering algorithms to re-adjust timing relationship between the MMT packets to assure synchronized playback. Thus, delivery of time constrained MPEG media on time, according to their temporal requirements, is an important goal of MMT. For this purpose MMT needs to specify syntax and semantics of a timing model to be used by the delivery functions. In this paper, we propose a proper timestamp-related header format for MMT delivery timing model to support media synchronization in various delivery scenarios including hybrid delivery.

• 한국통신학회논문지
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• 제21권4호
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• pp.1077-1088
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• 1996

In this paper, we propose a new method to analyze the performance degradation by timing jitters in the receivers of intensity modulation/direct detection digital optical communication systems where pulse-shaping filters are used to minimize intersymbol interference. The results obtained from the proposed analytical method show that conventional analytical methods underestimate the influence of timing jitters on the receiver performance. Using the proposed anlaytical method, we derive an analytic equation for approximated power penalty due to timing itters and obtain an exact power penalty by numerical analyses. Assuming Gaussian or uniform probability density function for timing jitters, we also show that assumption of Gaussian distribution for timing jitters yields more performance degration than that of uniform distribution.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.77-80
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• 1999

This paper deals with a design of a symbol timing recovery circuit of QAM using the interpolation in AWGN channel. To reduce timing jitter and the amount of processing data, we employ MGA (Modified Gardner Algorithm) as a symbol timing error detector which is called NDA(Nondecision Directed Algorithm). We show the characteristics (S-curve and the variance) of timing error detector with the roll-off factor of a shaping filter, which are compared with GA. Also, we compare the BER curve of interpolation method with that of ideal case. The performance of the STR is shown to be close to that of ideal case. This result shows that this method can be useful to implement symbol timing recovery circuit for multi-level modulation.

• 전자공학회논문지A
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• 제33A권6호
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• pp.206-219
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• 1996

This paper describes a data structure and evaluation algorithm to improve the perofmrances MOS logic-with-timing simulation in computation and accuracy. In order to efficiently simulate the logic and timing of driver-load networks, (1) a tree data structure to represent the mutual interconnection topology of switches and nodes in the driver-lod network, and (2) an algebraic modeling to efficiently deal with the new represetnation, (3) an evaluation algorithm to compute the linear resistive and capacitive behavior with the new modeling of driver-load networks are developed. The higher modeling presented here supports the structural and functional compatibility with the linear switch-level to simulate the logic-with-timing of digital MOS circuits at a mixed-level. This research attempts to integrate the new approach into the existing simulator RSIM, which yield a mixed-klevel logic-with-timing simulator MIXIM. The experimental results show that (1) MIXIM is a far superior to RSIM in computation speed and timing accuracy; and notably (2) th etiming simulation for driver-load netowrks produces the accuracy ranged within 17% with respect ot the analog simulator SPICE.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.461-465
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• 2005

애니메이션에서 움직임의 표현은 작품을 형성하는 가장 중요한 요소 중의 하나이다. 동작표현과 타이밍의 상호작용은 시각예술인 애니메이션을 이해하고 창작하는 기본적인 요소이며 이때 타이밍(Timing)이란 물체나 캐릭터가 움직이기 위해 소요되는 시간의 양을 말한다. 이 논문에서는 스톱모션 애니메이션의 에서의 타이밍의 기본원리를 밝히고 실험을 동해 카메라의 각도에 따라 변하는 타이밍을 실험, 비교하여 이상적인 타이밍 방법을 제시하고자 한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.1-4
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• 2004

We proposed a new type of timing recovery scheme to work with a system that uses BCJR (Bahl-Cocke-Jelinek-Raviv) decoding algorithm and BPSK modulation. The unknown timing offset is estimated by the modified Mueller and $M\ddot{u}ller$ estimator with the aid of the decoder. Timing offset can be acquired as soon as the symbols are received and be updated symbol by symbol. The simulation results for turbo codes whose decoder uses BCJR algorithm show a satisfactory performance even in case of severe timing jitter.