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

• 품질경영학회지
• /
• 제32권4호
• /
• pp.169-183
• /
• 2004

The synthetic control chart (SCC) proposed by Wu and Spedding (2000) is to detect shifts in the process mean. The performance was re-evaluated by Davis and Woodall (2002), and the steady-state average run length (ARL) performance was shown to be inferior to cumulative sum (CUSUM) or exponentially weighted moving average (EWMA) chart This paper proposes a simple adaptive scheme to improve the performance of the synthetic control chart. That is, once a non-conforming (NC) sample occurs, we investigate the next L-consecutive samples with larger sample sizes and shorter sampling intervals. We employ a Markov chain model to derive the ARL and the average time to s19na1 (ATS). We also propose a statistical design procedure for determining decision variables. Comprehensive comparative study shows that the proposed control chart is uniformly superior to the original SCC or double sampling (DS) Χ chart and comparable to the EWMA chart in ATS performance.

• 품질경영학회지
• /
• 제32권4호
• /
• pp.156-168
• /
• 2004

This research investigates the statistical efficiency of variable sampling size & sampling interval(VSSI) $\bar{X}$ charts under two assignable causes. Algorithms for calculating the average run length(ARL) and average time to signal(ATS) of the VSSI $\bar{X}$ chart are proposed by employing Markov chain method. States of the process are defined according to the process characteristics after the occurrence of an assignable cause. Transition probabilities are carefully derived from the state definition. Statistical properties of the proposed chart are also investigated. A simple procedure for designing the proposed chart is presented based on the properties. Extensive sensitivity analyses show that the VSSI $\bar{X}$ chart is superior to the VSS or VSI $\bar{X}$ chart as well as to the Shewhart $\bar{X}$ chart in statistical sense, even tinder two assignable causes.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
• /
• pp.863-874
• /
• 2009

The engineering characteristics and the reinforcement effect of the elephant foot method were discussed with parametric study. The elephant foot method is adopted to support the loads transferred from tunnel crown and improve bearing capacity of elephant foot in poor ground condition. The evaluation of reinforcement effect, which has the mechanical relationship between ground condition, footing size and reinforcement system, was carried out through the previous research and numerical analysis. In addition, the simple design chart was proposed to estimate the applicability of the elephant foot reinforcement method. It will be practical for the engineer to determine the optimum reinforcement method for safe tunnelling in soft ground condition.

• 한국품질경영학회:학술대회논문집
• /
• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
• /
• pp.217-224
• /
• 1998

A cost model, controlling multiple dependent subprocesses with minimum cost, is derived by renewal theory approach. The optimal multiple cause-selecting control chart and individual Y control chart are thus constructed to monitor the specific product quality and overall product quality contributed by the multiple dependent subprocesses. They may be used to maintain the process with minimum cost and effectively distinguish which component of the subprocesses is out of control. The optimal design parameters of the proposed control charts can be determined by minimizing the cost model using simple grid search method, An example is given to illustrate the application of the optimal multiple cause-selecting control chart and individual Y control chart.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
• /
• pp.185-192
• /
• 2004

The goal of this paper is to determine the accurate effective length factor(K factor) for buckling design of plane frames and to point out the practical limitations of the alignment chart which provides the approximate effective length factor. At present, the most general method to obtain K factors is to use the alignment chart which is given in the form of nomograph in LRFD-AISC specification commentaries. However it should be realized that various simplifications and assumptions were used in obtaining the alignment chart. Therefore, a simple but effective method to obtain accurate K-factors through the stability analysis of plane frames is developed in this study. To demonstrate the accuracy and effectiveness of the present scheme, K-factors by system buckling analysis of frames are calculated and compared with those calculated by the alignment chart.

• 한국통신학회논문지
• /
• 제35권7C호
• /
• pp.587-593
• /
• 2010

본 논문에서는 extrinsic information transfer (EXIT) chart를 이용하여 다중 안테나 시스템에서 irregular low-density parity-check (LDPC) code를 설계하는 방법을 기술한다. 다중 안테나 기반의 Irregular LDPC code 설계를 위하여 maximum a posteriori probability (MAP) 방식의 다중 안테나 검출 방식이 사용되었으며 수신기는 다중 안테나 검출기와 LDPC 복호기 사이에서 복호된 soft 정보를 주고 받는 turbo iterative 구조를 가정하였다. 다중 안테나 기반의 irregular LDPC code의 edge degree 분포는 EXIT chart와 linear optimization programming 기법을 사용하여 얻을 수 있으며 컴퓨터 시뮬레이션을 통하여 제안된 방법으로 설계된 irregular LDPC code의 성능을 다양한 환경에서 검증하였다.

• Earthquakes and Structures
• /
• 제9권3호
• /
• pp.455-480
• /
• 2015

In the last decade, displacement-based (DB) methods have become established design procedures for reinforced concrete (RC) structures. They use strain and displacement measures as seismic performance control parameters. As for other simplified seismic design methods, it is of great interest to prove if they are usually conservative in respect to more refined, nonlinear, time history analyses, and can estimate design parameters with acceptable accuracy. In this paper, the current Direct Displacement-Based Design (DDBD) procedure is evaluated for designing simple single degree of freedom (SDOF) systems with specific reference to simply supported RC bridge piers. Using different formulations proposed in literature for the equivalent viscous damping and spectrum reduction factor, a parametric study is carried out on a comprehensive set of SDOF systems, and an average error chart of the method is derived allowing prediction of the expected error for an ample range of design cases. Following the chart, it can be observed that, for the design of actual RC bridge piers, underestimation errors of the DDBD method are very low, while the overestimation range of the simplified displacement-based procedure is strongly dependent on design ductility.

• 산업경영시스템학회지
• /
• 제39권2호
• /
• pp.37-45
• /
• 2016

Control chart is representative tools of statistical process control (SPC). It is a graph that plotting the characteristic values from the process. It has two steps (or Phase). First step is a procedure for finding a process parameters. It is called Phase I. This step is to find the process parameters by using data obtained from in-controlled process. It is a step that the standard value was not determined. Another step is monitoring process by already known process parameters from Phase I. It is called Phase II. These control chart is the process quality characteristic value for management, which is plotted dot whether the existence within the control limit or not. But, this is not given information about the economic loss that occurs when a product characteristic value does not match the target value. In order to meet the customer needs, company not only consider stability of the process variation but also produce the product that is meet the target value. Taguchi's quadratic loss function is include information about economic loss that occurred by the mismatch the target value. However, Taguchi's quadratic loss function is very simple quadratic curve. It is difficult to realistically reflect the increased amount of loss that due to a deviation from the target value. Also, it can be well explained by only on condition that the normal process. Spiring proposed an alternative loss function that called reflected normal loss function (RNLF). In this paper, we design a new control chart for overcome these disadvantage by using the Spiring's RNLF. And we demonstrate effectiveness of new control chart by comparing its average run length (ARL) with ${\bar{x}}-R$ control chart and expected loss control chart (ELCC).

• KIEAE Journal
• /
• 제12권2호
• /
• pp.15-24
• /
• 2012

The purpose of this study is to understand children's participating behavior on the environment-improving process of a community child center, and to develop participating technique and tools that can be appliable. For this, a workshop, constructions, and an evaluation research were done on the premise that children participate in process of designing a community child center. The result of study is as follows. (1) A survey chart, questionaries, preference image chart, and attitude measurement chart used in this study were easy to understand, simple, and thus found to be a useful technique and tool that could make children participate more active and interested. (2) As children participated more on the environment-improving process of community child centers, their demands became more diverse and specific, and their levels of satisfaction were high. (3) The change of satisfaction level before construction and after, and consistent demands for the separation of studying space between upper and lower graders show that children understand their physical environment changes well, and have clear ideas on how their studying space should be composed.