Quality requirements of manufactured products or parts are given in the form of specification limits on the quality characteristics of individual units. If a product is to meet the customer’s fitness for use criteria, it should be produced by a process which is stable or repeatable. In other words, it must be capable of operating with little variability around the target value or nominal value of the product’s quality characteristic. In order to maintain and improve product quality, we need to apply statistical process control techniques such as histogram, check sheet, Pareto chart, cause and effect diagram, or control charts. Among those techniques, the most important one is control charting. The cumulative sum (CUSUM) control charts have been used in statistical process control (SPC) in industries for monitoring process shifts and supporting online measurement. The objective of this research is to apply Taguchi's quality loss function concept to cost based CUSUM control chart design. In this study, a modified quality loss function was developed to reflect quality loss situation where general quadratic loss curve is not appropriate. This research also provided a methodology for the design of CUSUM charts using Taguchi quality loss function concept based on the minimum cost per hour criterion. The new model differs from previous models in that the model assumes that quality loss is incurred even in the incontrol period. This model was compared with other cost based CUSUM models by Wu and Goel, According to numerical sensitivity analysis, the proposed model results in longer average run length in in-control period compared to the other two models.

This paper is focused on an economic analysis of applied air pollutant control technologies used for the particulate matters present in subway. Beneficial effects such as reduction in medical expenses and prevention of productivity loss and death are achievable through the adaptation of control technologies. The result showed that the total investment expense was 97.6 billion won and the cost-benefit was 4776.8 billion won, therefore a 4.8 benefit/ cost ratio was attained.

지난 몇 십년동안 전 세계적으로 제조기술 분야의 급속한 성장으로 대부분의 제조업에서 눈부실만한 품질향상과 생산성 극대화를 이루어 왔다. 하지만 현재 제조기술 분야는 새로운 문제에 직면하고 있다. 실제 현장에서 관리하고자하는 품질특성은 정규분포를 따르지 않는 경우가 많은데, 대부분의 통계적 공정관리기술체계가 정규분포를 기반으로 하고 있다는 것이다. 이러한 이유로 비정규 공정에서 극소불량관리, 미세변동관리에 대한 연구가 시급한 실정이다. 하지만 비정규 분포를 통계적으로만 해석하고 설계하기 위해서는 현실적으로 한계가 있으며, 경제적 설계의 접근방법이 또 하나의 좋은 대안이 될 수 있다. 본 논문에서는 비정규 공정에서 관리도의 경제적 설계를 위한 연구동향을 살펴보고 추후 연구방향에 대해 제시하고자 한다.

Control chart is representative tool of Statistical Process Control (SPC). But, it is not given information about the economic loss that occurs when a product is produced characteristic value does not match the target value of the process. In order to manage the process, we should consider not only stability of the variation also produce products with a high degree of matching the target value that is most ideal quality characteristics. There is a need for process control in consideration of economic loss. In this paper, we design a new control chart using the quadratic loss function of Taguchi. And we demonstrate effectiveness of new control chart by compare its ARL with   control chart.

Control chart is a graph of plotting dot about the process characteristic values. It is a statistical technique that can be known whether or not the in-control state in this step. In many companies have use as a statistical process control(SPC) tool. Control chart is the management process quality characteristic value, which is plotted dot is whether the existence within the control limits. This is not given information about the economic loss that occurs when a product is produced characteristic value does not match the target value of the process. In order to manage the process, we should consider not only stability of the variation also produce products with a high degree of matching the target value that is most ideal quality characteristics. There is a need for process control in consideration of economic loss. In this paper, we design a new control chart using the quadratic loss function of Taguchi. Use the control chart performance comparison of x-R, which is a traditional control chart, we demonstrate its effectiveness.

이 논문은 미세공정변동에서 극소불량을 감지하는 관리도의 경제적 설계를 개발하기 위한 조사연구이다. 일반적인 관리도의 설계는 통계적 설계와 경제적 설계로 구분할 수 있다. 공정의 변동 원인에 따라 샘플의 간격(h), 샘플의 크기(n), 관리한계선(k) 등의 설계 모수를 최적접근방법으로 결정을 하는 경제적 설계의 모델을 조사하였다. 관리도의 경제적 설계는 공정의 관리이상상태를 효율적으로 감지하여 관리상태로 정상화 시키는 것에 대한 공정의 개선비용과 기대품질비용을 절약 할 수 있는 최적설계 방안이다. 그리고 Shewhart 관리도의 X-bar 통계량으로 극소불량을 검출 하는것에 한계가 있기 때문에 Zp 통계량과 분포를 설계하여 극소불량을 빠르게 감지할 수 있는 Zp 관리도의 설계를 적용하고, 미세공정변동을 정확하게 감지할 수 있는 CUSUM 관리도를 동시에 적용하였다. 따라서, 미세공정변동과 극소불량을 동시에 관리 할 수 있는 Zp-CUSUM 관리도의 통계적 설계 구조를 체계화 하였으며, 기존의 경제적 설계의 모델을 비교 분석하여 새로운 경제적 설계에 대한 모델을 제안하고자 한다.

Economic injury levels (EILs) and economic control threshold (ET) were estimated for the Tea red spider mite, Tetranychus kanzawai Kishida(Acari, Tetranychidae) in Rubus coreanus Miquel. T. kanzawai density increased until the early-July and thereafter decreased in all plots except the non-innoculation plot where initial density of the mite were different each 0，5, 10, 20 and 40 adults per plant branch on May 7 in 2008. And the occurrence of the densities were increased higher innoculated density than different innoculation density. The yield was decreased with increasing initial mite density and thereby the rates of yield loss was increased with increasing initial mite density. And T. kanzawai occurrence density, yields and the rates of yield loss, where initial density of the mite were different each 0,2, 5, 10 and 20 adults per plant branch on May 8 in 2009 were similar tendency to 2008 year results. The relationship between initial T. kanzawai densities and the yield losses was well described by a linear regression, Y = 0.6545X + 3.0425 (R<SUP>2</SUP> = 0.93) in 2008, Y = 0.9031X + 2.0899(R<SUP>2</SUP> = 0.96) in 2009. Based on the relationship, the number of adults per plant branch(EILs) which can cause 5% loss of yield was estimated to be approximately 3.0 in 2008 and 3.2 in 2009. And the ET was estimated to be approximately 2.4 in 2008 and 2.6 in 2009. The relationship between initial T. kanzawai densities and occurrence density of mid-May considering the best spray timing against T. kanzawai was well described by a linear regression, Y = 0.471X + 2.495(R<SUP>2</SUP> = 0.95) in 2008, Y = 0.9938X + 3.1858(R<SUP>2</SUP> 二 0.96) in 2009. Based on the relationship, the number of adults per Ieaf(ET) in mid-May which can cause 5% loss of yield was estimated to be approximately 3.6 in 2008 and 5.8 in 2009.

This study was conducted for establishment of Economic injury levels(EILs) of the tea red spider mite, Tetranychus kanzawai on Rubus coreanus. T. kanzawai was innoculated on May 7 in differently 0, 5, 10, 20 and 40 adults per plant. And pesticide was treated in late April, early May, middle May and late May, respectively. After inoculated of T. kanzawai, the density was increased until the mid-June and decreased gradually in all plots. And higher inoculation density were increased higher than lower inoculation density. Growth variables were not different among experimental plots except number of fruit set, but the number of fruit set and yields were decreased with increasing initial mite density. Densities of T. kanzawai on treated time of pesticide was lower in later treatment time than early treatment time. The late April treatments were not effective of pesticide in harvesting season. The rates of yield loss increased with increasing initial mite density. The relationship between initial T. kanzawai densities and yield losses was well described by a linear regression, Y = 0.6545X + 3.0425, R2=0.9313. Based on the relationship, the number of adults per plant which can cause 5% loss of yield was estimated to be approximately 3.0. And EILs was estimated to be approximately 8.3 adults/leaf in mid-May.

Economic injury level and control thresholds for the management of beet army worm, Spodoptera exigua (Lepidoptera: Noctuidae) were evaluated on chinese cabbage of two different planting time. Two inoculation times were tested for each planting and the number of inoculated larva was 10, 20, 40, 80, respectively. Damages of leaves by first inoculation were 63.2% after eight days planting on 80 larva inoculation plot. By the second inoculation, those were below 50% after 20 days planting on the end of September. The linear relationships between population density and yield reduction were as following, Y = -10.62x + 867.9 (R² = 0.643) for 5 days and Y=-6.432x + 1074 (R² = 0.720) for 20 days. Based on these results the economic injury level was 5.4 larva for five days and 9.0 larva for 20 days per 20 chinese cabbage. The control thresholds calculated by 80% level of economic injury level were 4.3 and 7.2 larva, respectively.

Pyrausta panopealis is the major pest in green perilla. The larva weaves a web on the shoot of green perilla and damages. In case of extreme, The larva cuts the main branch of green perilla and the leaf of green perilla isn’t harvested anymore. A field study was conducted to estimate economic injury levels (EILs) and control thresholds (CTs) for P. panopealis injuring green perilla in green-houses. Different densities of P. panopealis ranged from 1 to 20 crops (2 units per crop) per 100 crops on 13. June, early inoculation. The number of injured leaf and the rate of injured crop were increased by 23. June, on the other hand were decreased after that day. Also, the amount of yield sow the same result above. The economic loss time calculated by the ratio of cost managing this moth to market price (C/V) (C: cost managing a moth, V: Market price) was 4.0%. The economic injury level was 5.1 larval per 100 crops. The control thresholds calculated by 80% level of economic injury level was 4.1 larval per 100 crops.

According to the preceding survey on insect pests of the green perilla, Perilla frutescens var. japonica HARA, The major pests were Aphis egomae Shinji, Pyrausta panopealis (Walker), Tetranychus urticae Koch, Polyphagotarsonemus latus Banks, Tetranychus kanzawai Kishida at Guemsan, Chungnam, 2004. Aphis egomae causes nearly 100% injury of the green perilla in uncontrolled green houses. A field study was conducted to estimate economic injury levels (ElLs) and control thresholds (CTs) for A. egomae injuring green perilla in green houses. Different densities of A. egomae ranged from 1 to 80 aphids per 100 plants in early inoculation. The mean injurying rate of plant was 2.4% to 40.5% at the end of June at differently inoculated levels. The economic loss time calculated by the ratio of cost managing aphid to market price (C/V) (C: cost managing aphid, V: Market price) in early season (from May to 13. June) was 5.8% and in peak season (from 13. June to 30. June) was 9.3%. Economic injury level in early and peak season was 5.3 aphids per plant and economic injury levels in peak season were 0.6 aphids per plant and 7.6% injured rate of plant. The control thresholds calculated by 80% level of economic injury level in peak season were 0.5aphids per plant and 6.1% injury rate of plant, respectively.

This paper is designed a VSI X-CRL synthetic control chart in aspect of economy. We found the optimal sampling interval and various control limit factors under various cost parameters using cost function, proposed Lorenzen and Vance. Optimal design parame

In statistical process control applications, variable sample size (VSS) chart is often used to detect the assignable cause quickly. However, it is usually assumed that only one assignable cause results in the out-of-control in the process. In this paper,

This paper presents a economic design of synthetic control chart that is an VSI(variable samlping interval) X control chart and conforming run length chart. Computer simulation is carried out for comparing performance of developed control chart with X-CRM synthetic chart. We found that optimal parameter of suggested chart for minimize quality cost. And then a comparison and analysis between synthetic VSI X-CRL chart and X-CRM synthetic chart in the economic aspect. Then VSI X-CRL chart consistently produces smaller quality cost than X-CRM synthetic chart.

VSS X 관리도는 이상원인에 의한 공정의 변동이 작은 경우에 통계적으로나 경제적으로 효과적인 관리도이다. 본 연구에서는 두 가지 이상원인이 공정의 평균에 복합적으로 영향을 끼치는 경우 VSS X 관리도의 최적 샘플 크기 결정을 위한 경제적 모형을 제시한다.

The study aims to investigate the dual effects of corruption control on economic growth in relationship with the stock market and trade openness in developing countries. The study used difference S-GMM method on the dynamic panel data model in the period (2002-2017) with data collected from the World Bank. The study discovers the dominant impacts of corruption control in the relationship with the stock market on economic growth. At the same time, the study also confirms the overwhelming impact of corruption control in the relationship between trade openness and economic growth in the developing countries. In addition, the study shows that inefficient stock markets in developing countries will not promote economic growth. Meanwhile, the long-standing credit market has a positive impact on economic growth. With the strong development of stock market and trade openness in the period (2002-2017), control on corruption in developing countries does not get better in time with the increase in demand. The findings of this study suggest a number of solutions to strengthen corruption control, leading to the increased efficiency on the stock market and as well as encouraging the positive effects of trade openness to contribute to promoting economic growth in developing countries.

상당한 국가예산이 투입되는 공공목적의 치수사업은 그 성공여부가 국가경제 전반에 걸쳐 큰 영향을 미치는 만큼 보다 정확하고 합리적인 경제성분석 결과를 바탕으로 타당성을 판단해야 한다. 그 동안 국내에서는 치수경제성분석 시 2004년의 치수사업 경제성분석 방법 연구에서 수행되어 개발된 다차원 홍수피해산정법(Multi-Dimension Flood Damage Assessment; MD-FDA)을 바탕으로 치수사업의 경제성 및 타당성을 계량적으로 평가하는데 실무에서 널리 사용되고 있으며, 이는 현재 KDI에서 수행하는 예비타당성조사에서도 채택되어 국내 대표적인 홍수피해산정법이라 할 수 있다.<br>이러한 MD-FDA를 적용하기 위해서는 각종 통계자료뿐만 아니라 토지피복도, 행정구역도, 침수구역도와 같은 GIS 공간자료의 수집 및 구축, 그리고 Spatial Analyst, 3D Analyst 기능 등의 공간분석 과정을 필요로 하며, 이와 더불어 자산분석, 홍수피해액 산정, 경제성분석 등에서 수자원 분야 지식뿐만 아니라 경제학적 지식이 다소 요구된다. 이러한 측면에서 치수경제성분석은 수자원 분야에서 다소 낯선 학문으로 취급되어 왔으며, 적용과정 또한 높은 이해도를 바탕으로 수행하기에는 한계가 있었다.<br>이에 본 연구는 통일된 분석체계를 바탕으로 자동화 실용 목적의 치수경제성분석 시스템(EAF)을 개발하였다. 본 시스템은 치수경제성분석 과정에서 요구되는 정확한 위치정보 탐색을 위하여 GIS 기반으로 설계(stand alone)하였으며, 시스템에서 지원하는 주요 기능은 치수경제성분석 시 필요한 공간데이터의 처리(침수구역도 생성 모듈 포함), 자산분석, 침수편입률 산정, 피해액 산정, 경제성분석이다. 본 연구에서 개발한 MD-FDA 기반의 치수경제성분석 시스템은 향후 치수사업의 경제성 및 타당성을 확인하는 의사결정 단계에서 보다 객관적이고 합리적인 분석도구의 역할을 담당할 것으로 기대한다.

기존의 댐 계획이나 운영에서는 댐의 홍수조절 효과분석을 위해 댐 홍수조절 기여도 평가, 유황변화, 환경생태학적 변화 및 댐 하류의 수위저감효과를 사용하고 있다. 그러나 이와 같은 분석방법은 댐의 홍수조절에 의한 경제석 효과를 명확하게 제시할 수 없기 때문에, 댐의 치수역할과 필요성에 대한 국민적 공감대 형성이나 댐 사업의 타당성을 정확하게 평가하고 알리기에는 한계가 있다고 판단된다. 따라서 본 연구에서는 댐의 홍수조절에 의한 효과를 보다 분명하고 정확하