• International Journal of Automotive Technology
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• 제8권3호
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• pp.259-268
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• 2007

A knock detection circuit that is based on the signal of an accelerometer installed on the engine block of a spark ignition automotive engine has a band-pass filter with a certain frequency as a parameter to be calibrated. A new statistical method for the determination of the frequency which is the most suitable for the knock detection in real-time applications is proposed. The method uses both the cylinder pressure and block vibration signals and is divided into two steps. In both steps, a new recursive trigonometric interpolation method that calculates the frequency contents of the signals is applied. The new trigonometric interpolation method developed in this paper improves the performance of the Discrete Fourier Transformation, allowing a flexible choice of the size of the moving window. In the first step, the frequency contents of the cylinder pressure signal are calculated. The knock is detected in the cylinder of the engine cycle for which at least one value of the maximal amplitudes calculated via the trigonometric interpolation method exceeds a threshold value indicating a considerable amount of oscillations in the pressure signal; this cycle is selected as a knocking cycle. In the second step, the frequency analysis is performed on the block vibration signal for the cycles selected in the previous step. The knock detectability, which is an individual cylinder attribute at a certain frequency, is verified via a statistical hypothesis test for testing the equality of two mean values, i.e. mean values of the amplitudes for knocking and non-knocking cycles. Signal-to-noise ratio is associated in this paper with the value of t-statistic. The frequency with the largest signal-to-noise ratio (the value of t-statistic) is chosen for implementation in the engine knock detection circuit.

• 경영정보학연구
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• 제9권1호
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• pp.311-341
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• 2007

본 연구는 공기업형 조직인 우정사업본부에 대한 BSC(Balanced Scorecard)시스템 구축사례를 제시한다. 일반적으로 공공부문과 민간부문의 BSC 모델은 서로 상이한 전략목표로 인해 각각 다른 형태로 구축된다. 우정사업본부는 현재 정부기업으로서 공공부문의 성격을 많이 내포하고 있으면서, 또한 민간부문과 유사한 BSC 특성을 가지고 있다. 즉 민간기업이 아닌 공기업으로서의 조직의 형태를 띠고 있다. 현재 공기업을 포함하는 많은 정부 산하기관들이 BSC를 도입했거나, 도입하려고 하지만, BSC에 대한 이해부족으로 말미암아 예상보다 BSC 시스템을 성공적으로 구축하는데 많은 어려움을 겪고 있다. 이에 본 연구에서는 우정사업본부의 BSC 사례분석을 통해 공기업의 BSC 시스템 구축의 주요 성공요인과 문제점을 분석하고, 향후 공기업의 BSC 시스템을 위한 발전방향을 제시하였다.

• Journal of the Korean Data and Information Science Society
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• 제24권3호
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• pp.465-475
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• 2013

공정능력을 측정하고 분석하기 위하여 공정능력지수가 매우 중요한 역할을 한다. 흔히 품질수준은 공정능력지수들에 의해 측정된다. 세 가지 공정능력지수 $C_p$, $C_{pk}$, $C_{pm}$들은 품질 현장에서 프로세스 성과를 평가하는 데 널리 유용하게 사용되는 바, 이들 추정량들의 상관관계를 보다 명확하게 규명, 연구하여 적절히 활용할 필요가 있다. 본 논문에서는 공정표본이 정규분포에 따를 때 이러한 지수들의 추정량들에 대한 점근적 상관성을 연구하였다. 제2절에서는 공정능력지수 $C_p$, $C_{pk}$, $C_{pm}$들을 정의하여 기본적인 관계를 설명하였고, 제3절에서는 단일변량 정규공정하에서의 점근적인 상관계수를 구체적으로 계산, 규명하였다. 이러한 연구결과를 이용하여 보다 정확한 공정능력지수들의 상관관계를 통해 필요한 분석을 수행하는 것이 바람직할 것이다.

• 자동차안전학회지
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• 제7권1호
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• pp.7-12
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• 2015

NCAP(New Car Assessment Program) makes vehicle manufacturer improve safety performance through free competition and customers guarantee vehicle selection by providing information of vehicle safety. That's why it is important not only to meet the regulation, but also to cope with NCAP. EuroNCAP(European New Car Assessment Program) side tests have conducted by using Progressive MDB and Euro SID II in order to reproduce crash test between two vehicles over 10 years. However various researches report that Progressive MDB and Euro SID II do not reflect evolving vehicle design, impact performance and biofidelity of human. Therefore EuroNCAP has the plan to conduct AE-MDB side crash test using WorldSID which is more evolved from 2015 by replacing Progressive MDB and EuroSID II. Automobile manufacturers need to develop safety performance for new test closely. This paper is to find test set-up parameters which affect into dummy injury instead of restraint system and to research on its tendency. It is processed with mini and small car to know influence as changing vehicle size and also analyzed by DFSS(Design for six sigma) which is one of optimization tools. DFSS is vaildated by simulating CAE with L18 orthogonal array of 6 control factors adjustable as EuroNCAP requirement.

• 디지털산업정보학회논문지
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• 제11권4호
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• pp.113-127
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• 2015

An interface in smart device environment is changing to TUI(touch user interface) environment where a system is being controlled by physical touch, differently from a system controlled through conventional mouse and keyboard. What is more important than anything else in this TUI environment is to implement interface in consideration of learn ability and cognitive constructivism according to user's experience. Therefore, now is the time when it is necessary to carry out various studies on smart content design process going a step farther together with discussing the details of user's experience factor. Hence, this study was intended to look into what effect a user's experiential traits had on the production of contents for the purpose of measures for improving TUI user satisfaction in order to effectively realize contents in smart environment. Results were yielded by using a statistical empirical analysis such as cross-tabulation analysis according to important variable and user, paired t-test, multiple response analysis, and preference frequency analysis of user preference on the basis of a survey. As a result, a system was presented for implementing DFSS(Design For Six Sigma) process. TUI experience factor can be divided into direct habitual experience, direct learning experience, indirect habitual experience, and indirect learning experience. And in the results of study, it was possible to find that the important variables of this study had a positive effect on the improvement of use satisfaction with contents on the whole according to the user convenience of smart contents. This study is expected to have a positive effect on efficient smart device-based contents production by providing objective information according to empirical analysis to smart media-based developer and designer and presenting a model for improving the changed TUI usability.

• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1759-1764
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• 2002

Two crystal structures of dehydrated $Ag^+-andTl^+$-exchanged zeolite X$Ag_{27}Tl_{65-}X\;and\;Ag_{23}Tl_{69-}X$have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21(1) $^{\circ}C(a=24.758(4)\AAa=24.947(4)$, ${\AA}respectively).$, Their structures were refined to the final error indices $R_1$=0.055 and $wR_2$=0.057 with 375 reflections, and $R_1$=0.057 and $wR_2$=0.057 with 235 reflections, respectively, for which I > $3\sigma(I).$ In the structure of $Ag_{27}Tl_{65-}X,\;27\;Ag^+$ ions were found at two crystallographic sites: 15$Ag^+$ ions at site I at the center of the hexagonal prism and the remaining 12$Ag^+$ ions at site II' in the sodalite cavity. Sixty-five $Tl^+$ ions were located at three crystallographic sites: 20$Tl^+$ ions at site II opposite single six-rings in the supercage, 18$Tl^+$ ions at site I' in the sodalite cavity opposite the D6Rs, and the remaining 27$Tl^+$ ions at site III' in the supercage. In the structure of $Ag_{23}Tl_{69-}X$, 23$Ag^+$ ions were found at two crystallographic sites: 15 at site I and 8 at site II'. Sixty-nine $Tl^+$ ions are found at four crystallographic sites: 24 at site II, 17 at stie I', and the remaining 28 at two III' sites with occupancies of 22 and 6.

• Journal of Periodontal and Implant Science
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• 제27권3호
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• pp.443-457
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• 1997

The purpose of this study was to evaluate the effects of ethanolic extracts of Scutellaria Radix on the alveolar bone formation in the extract socket of rat. Thirty-six Sprague-dawley rats were used in this study. Mean body weight of rat was $130{\pm}5g$. Experimental animal were administered 0.4% ,${\beta}-aminopropionitril$(Sigma, USA) with the solid commercial food for 5 days. All the maxillary 1st molar of the rats were extracted by using of the tissue forcep under the general anesthesia with Pentobarbital sodium(Tokyo Chemical Co, Japan) injection into intraperitoneal space. All the extracted rats were divided into two group, experimental group which were feeded the solid food mixed ethanolic extracts of Scutellaria Radix, and control group which were feeded same food without reagent. At 1, 3, 5, 7, 9 and 14th days after tooth extraction, rats in both groups were serially sacrificed respectively. All the specimen were treated as usual method and prepared Hematoxylin-eosin stain for the light microscopic observation. The results were as follows : 1. Bone formation of extracted socket starts from the area on remained periodontal ligament than other area. 2. In the case of administration of the extracted Scutellaria Radix showed rapid healing process of connective tissue than non-administrated group. 3. In the case of administration of the extracted Scutellaria Radixshowed rapid osteogenesis than non-administrated With above results, it was concluded that ethanolic extracts of Scutellaria Radix may play a favorable role on the healing process of exatraction socket after extraction in rats. It was suggested that further study to evaluate the different concentration and administration method of ethanolic extracts of the Scutellaria Radix into same experimental model.

• 정보처리학회논문지D
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• 제13D권5호
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• pp.691-698
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• 2006

기업은 지속적인 경쟁 우위를 확보하기 위해 전략을 수립하고 추진하는 과정에서 변화가 심한 시장의 소리를 정확히 수집할 수 있는 역량과 이를 위한 비즈니스 프로세스의 구축 및 관리를 해야 한다. 비즈니스 프로세스의 수립, 운영, 개선, 평가 등 프로세스와 관련된 전 과정에서 업무 규칙과 프로세스를 정의하고 측정하여 기업의 문화에 맞게 프로세스를 정확하고 효율적으로 수행할 수 있어야 한다. 본 논문에서는 기업에서 수행하는 업무에 대해 규칙과 프로세스를 룰로 정의하여 프로세스의 정확한 수행을 가능하게 하고자 한다. 또한, 프로세스 수행의 주체인 개개인의 역량에 대한 정확한 데이터의 수집과 반영을 통해 프로세스 수행 결과에 대한 결함을 미리 예방할 수 있고 프로세스 개선점을 식별할 수 있는 기반 환경을 제안하였다. 이로써 룰로 표현한 업무 지식과 프로세스를 활용하여 높은 가시성을 확보할 수 있으며 철저한 측정 데이터 기반의 프로세스 개선을 통해 프로세스 중심의 업무 문화(혹은 시스템)를 조직에 정착시키는데 일조할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.70-74
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• 1992

Two crystal structures of ethylene (a= 12.272(2) ${\AA}$) and acetylene (a = 12.245(2) ${\AA}$) sorption complexes of dehydrated fully $Ca^{2+}$-exchanged zeolite A have been determined by single crystal X-ray diffraction techniques in the cubic space group, Pm3m at $21(1)^{\circ}C$. Their complexes were prepared by dehydration at $360^{\circ}C$ and $2{\times}10^{-6}$ Torr for 2 days, followed by exposure to 200 Torr of ethylene gas and 120 Torr of acetylene gas both at $24^{\circ}C$, respectively. The structures were refined to final R (weighted) indices of 0.062 with 209 reflections and 0.098 with 171 reflections, respectively, for which I > 3${\sigma}$(I). The structures indicate that all six $Ca^{2+}$ ions in the unit cell are associated with 6-oxygen ring of the aluminosilicate framework. Four of these extend somewhat into the large cavity where each is coordinated to three framework oxide ions and an ethylene molecule and/or an acetylene molecule. The carbon to carbon distance in ethylene sorption structure is 1.48(7) ${\AA}$ and that in acetylene sorption structure 1.25(8) ${\AA}$. The distances between $Ca^{2+}$ ion and carbon atom are 2.87(5) ${\AA}$ in ethylene sorption structure and 2.95(7) ${\AA}$ in acetylene sorption structure. These bonds are relatively weak and probably formed by the electrostatic attractions between the bivalent $Ca^{2+}$ ions and the polarizable ${\pi}$-electron density of the ethylene and/or acetylene molecule.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.149-156
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• 2011

The performance measurement of construction firms is considered as a competitive advantage to develop and improve their performance to have place in the market and stay able to face the continuous challenge. Egyptian construction firms (ECF) started recently to adopt quality management system (QMS) as a way to develop and improve their performance as previous studies showed. However, measuring that performance to include all the firm's aspects in a competitive way is a crucial process for the ECF's culture. The research is trying to indicate the role of the QMS implementation in measuring performance (MP) through developing a model for measuring performance on the organization level, and explore its impact on the organization that adopt quality management system. This model is based on specific elements and their related indicators which have been derived from national approaches and models of measuring performance (benchmarking, quality awards and six sigma).Elements determination and the status of their real practice has been investigated through a questionnaire to a representative sample of ECF. This model determines the performance level (PL) of the organization that measured by a mean of a point system. Weights of the elements in the point system considered both the elements' importance in the international models and its real practice in the Egyptian construction firms. So, the final outcome of the model reveals the level of firm performance that helps the firm to identify the weak points against the strong ones, Confirm the priorities and identify new opportunities for developing, and Check the position of the company in the market among the others. Another questionnaire has been developed to be distributed on a group of Experts on measuring performance for the purpose of model validation. The majority of surveyed experts agreed that the proposed model can be applied effectively.