• Title/Summary/Keyword: Quality Sensitivity

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Development of Virtual Endoscopy and Evaluation of Performance as a 3D Virtual Colonoscopy (가상내시경의 개발 및 가상 대장내시경으로 적용 시 성능평가)

  • 김정훈;이상훈;고성호;김상준
    • Journal of Biomedical Engineering Research
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    • v.24 no.2
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    • pp.69-75
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    • 2003
  • Virtual colonoscopy is one of the Powerful tool for non-invasive colon examination and many in-vitro and in-vivo studies have shown its accuracy in Polyp or adenoma detection. But most of virtual colonoscopy requires high quality workstation and software and its cost is high to setup whole system. We developed PC-based 3D model creation and navigation program which has diverse functions. It can be easily installed to PC and connected to network system. The performance. when used as a virtual colonoscopy. is evaluated by calculating sensitivity of detection for the simulated polyp which is artificially made inside the Pig's colon and checked its clinical feasibility, Its total sensitivity is 76%. Grouping according to Polyps diameter, the sensitivity for detection of polyps 10 ㎜ or larger was 100%(40 of 40); 5.0-9.9 ㎜, 90.0(90 of 100): and smaller then 5 ㎜. 36.7%(22 of 60).

The study on the disk grinding using neural network and Input sensitivity analysis (신경망 및 입력인자 민감도 분석을 이용한 연삭디스크의 가공조건 예측에 관한 연구)

  • 이동규;유송민;이위로;신관수
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.04a
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    • pp.3-8
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    • 2004
  • When most manufacturing company produce grinding product operators decide grinding condition by experience and subjective judgment. The study on grinding manufacture have been developed to get the grinding condition with the same result when non-experienced or experienced worker work. The objective of this study is to develope the grinding condition and predict the result of grinding by neural network. Several discussions were made in following areas as; getting MRR with image processing, the architecture optimization of neural network with experiment design, analysis of the input neurons using sensitivity approach. The results showed that the developed approach was the best method in predicting grinding condition with respect to surface finish quality.

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Analytical Method to Analyze the Tolerance Effect on the Vehicle Ride Comfort (차량 승차감에 미치는 공차의 영향 분석을 위한 해석적 방법)

  • Kim, Beom-Seok;Yoo, Hong-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.7
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    • pp.549-555
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    • 2008
  • Analytical method to analyze the tolerance effect on the vehicle ride comfort is suggested in this paper. Ride comfort is one of the most important performance indices which decide the vehicle design quality. In general, the ride comfort is affected by the variations of parameters of a vehicle model. Therefore, the effects of the parameters on the ride comfort need to be evaluated statistically based on the whole-body vibration of the vehicle. In this paper, weighted RMS values of the acceleration PSD of a seat position are used to define the ride comfort. The equations of motion and the sensitivity equations are derived based on a 5-DOF vehicle model. By employing the sensitivity information of the acceleration at the seat position, the tolerance effect on the vehicle ride comfort could be effectively analyzed.

An Improved Identification Method for Joint Parameters in Structures with Imcomplete Modal Parameters (불완전 모우드 변수를 이용한 구조물 결합부 변수 규명 방법의 개선)

  • 홍성욱
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1998.04a
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    • pp.244-249
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    • 1998
  • The present paper improves the direct identification scheme based upon the equation error formulation with incomplete modal data. First, an indirect estimation technique is considered for estimating unmeasured elements of latent vectors by the combined use of a model and measured incomplete eigen vectors. It is used for estimating the other elements of eigen vectors, which are essential for identification but not available. Next an index is introduced here to indicate the quality of estimation with respect to the mode and the measured positions. A sensitivity formula for eigenvalues with respect to the unknown joint coefficient is also derived to select the modes appropriate for identification. An identification strategy is suggested to meet with practical problems with the help of the index and sensitivity formula. The index and the sensitivity are proved to be useful for selecting measurement positions and modes appropriate for identification A comprehensive simulation study is performed to test the proposed method.

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엔진 마운트의 interm 브라켓 공진 주파수 target 설정에 관한 연구

  • Sun, Jungwoog;Woo, Sunggeun;Jeon, Byounkeun;Kim, Dalsik;Kang, Shinnam
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.10a
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    • pp.769-772
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    • 2013
  • When developing engine mount, interm mount bracket 1st resonance is critical to make sound quality better or worse. So, at the initial stage of development, we need to consider some design parameter to setup the target of interm bracket 1st resonance. Especially, 3cylinder interm bracket guideline is not well known. So, this paper deals with some important sensitivity which should be considered during the development of vehicle. From source to interior side, we should know the component sensitivity like body sensitivity p/F or bracket gain etc. Through this paper, we could get the knowledge of design guideline and key consideration points.

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An Analysis on Effects of the Initial Condition and Emission on PM10 Forecasting with Data Assimilation (초기조건과 배출량이 자료동화를 사용하는 미세먼지 예보에 미치는 영향 분석)

  • Park, Yun-Seo;Jang, Im-suk;Cho, Seog-yeon
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.5
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    • pp.430-436
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    • 2015
  • Numerical air quality forecasting suffers from the large uncertainties of input data including emissions, boundary conditions, earth surface properties. Data assimilation has been widely used in the field of weather forecasting as a way to reduce the forecasting errors stemming from the uncertainties of input data. The present study aims at evaluating the effect of input data on the air quality forecasting results in Korea when data assimilation was invoked to generate the initial concentrations. The forecasting time was set to 36 hour and the emissions and initial conditions were chosen as tested input parameters. The air quality forecast model for Korea consisting of WRF and CMAQ was implemented for the test and the chosen test period ranged from November $2^{nd}$ to December $1^{st}$ of 2014. Halving the emission in China reduces the forecasted peak value of $PM_{10}$ and $SO_2$ in Seoul as much as 30% and 35% respectively due to the transport from China for the no-data assimilation case. As data assimilation was applied, halving the emissions in China has a negligible effect on air pollutant concentrations including $PM_{10}$ and $SO_2$ in Seoul. The emissions in Korea still maintain an effect on the forecasted air pollutant concentrations even after the data assimilation is applied. These emission sensitivity tests along with the initial condition sensitivity tests demonstrated that initial concentrations generated by data assimilation using field observation may minimize propagation of errors due to emission uncertainties in China. And the initial concentrations in China is more important than those in Korea for long-range transported air pollutants such as $PM_{10}$ and $SO_2$. And accurate estimation of the emissions in Korea are still necessary for further improvement of air quality forecasting in Korea even after the data assimilation is applied.

Discount Presentation Framing & Bundle Evaluation: The Effects of Consumption Benefit and Perceived Uncertainty of Quality (묶음제품 가격 할인 제시 프레이밍 효과: 지각된 소비 혜택과 품질 불확실성의 영향을 중심으로)

  • Im, Meeja
    • Asia Marketing Journal
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    • v.14 no.1
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    • pp.53-81
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    • 2012
  • Constructing attractive bundle offers depends on more than an understanding of the distribution of consumer preferences. Consumers are also sensitive to the framing of price information in a bundle offer. In classical economic theory, consumers' utility should not change as long as the total price paid stays same. However, even when total prices are identical, consumers' preferences toward a bundle product could be different depending on the format of price presentation and the locus of price discount. A weighted additive model predicts that the impact of a price discount on the overall evaluation of the bundle will be greater when the discount is assigned to the more important product in the bundle(Yadav 1995). Meanwhile, a reference dependent model asserts that it is better to assign a price discount to a tie-in component that has a negative valuation at its current offer price than to a focal product that has a positive valuation at its current offer price(Janiszewski and Cunha 2004). This paper has expanded previous research regarding price discount presentation format, investigating the reasons for mixed results of prior research and presenting new mechanisms for price discount framing effect. Prior research has hypothesized that bundling is used to sell a tie-in component with an offer price above the consumer's reference price plus a focal product of the same offer price with reference price(e.g., Janiszewski and Cunha 2004). However, this study suggests that bundling strategy can be used for increasing product's attractiveness through the synergy between components even when offer prices of bundle components are the same with reference prices. In this context, this study employed various realistic bundle sets with same price between offer price and reference price in the experiment. Hamilton and Srivastava(2008) demonstrated that when evaluating different partitions of the same total price, consumers prefer partitions in which the price of the high-benefit component is higher. This study determined that their mechanism can be applied to price discount presentation formats. This study hypothesized that price discount framing effect depends not on the negative perception of tie-in component with offer price above reference price but rather on the consumers' perceived consumption benefit in bundle product. This research also hypothesized that preference for low-benefit discount mechanism is that perceived consumption benefit reduces price sensitivity. Furthermore, this study investigated how consumers' concern for quality in a price discount--a factor not considered in previous research--influences price discount framing. Yadav(1995)'s experiment used only one magazine bundle of relatively low quality uncertainty and could not show the influence of perceived uncertainty of quality. This study assumed that as perceived uncertainty of quality increases, the price sensitivity mechanism for assigning the discount to low-benefit will increase. Further, this research investigated the moderating effect of uncertainty of quality in price discount framing. The results of the experiment showed that when evaluating different partitions of the same total price and the same amount of discounts, the partition that discounts in the price of low benefit component is preferred to the partition that decreases the price of high benefit component. This implies that price discount framing effect depends on the perceived consumption benefit. The results also demonstrated that consumers are more price sensitive to low benefit component and less price sensitive to high benefit component. Furthermore, the results showed that the influence of price discount presentation format on the evaluation of bundle product varies with the perceived uncertainty of quality in high consumption benefit. As perceived uncertainty of quality gradually increases, the preference for discounts in the price of low consumption benefit decreases. Besides, the results demonstrate that as perceived uncertainty of quality gradually increases, the effect of price sensitivity in consumption benefit also increases. This paper integrated prior research by using a new mechanism of perceived consumption benefit and moderating effect of perceived quality uncertainty, thus providing a clearer explanation for price discount framing effect.

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Sensitivity analysis of satellite-retrieved SST using IR data from COMS/MI

  • Park, Eun-Bin;Han, Kyung-Soo;Ryu, Jae-Hyun;Lee, Chang-Suk
    • Korean Journal of Remote Sensing
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    • v.29 no.6
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    • pp.589-593
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    • 2013
  • Sea Surface Temperature (SST) is the temperature close to the ocean's surface and affects the Earth's atmosphere as an important parameter for the climate circulation and change. The SST from satellite still has biases from the error in specifying retrieval coefficients from either forward modeling or instrumental biases. So in this paper, we performed sensitivity analysis using input parameter of the SST to notice that the SST is most affected among the input parameter. We used Infrared (IR) data from the Communication, Ocean, and Meteorological Satellite (COMS)/Meteorological Imager (MI) from April 2011 to March 2012. We also used the Global Space-based Inter-Calibration System (GSICS) correction to quality of the IR data from COMS. SST was calculated by substituting the input parameters; IR data with or without the GSICS correction. The results of this sensitivity analysis, the SST was sensitive from -0.0403 to 0.2743 K when the IR data were changed by the GSICS corrections.

Periodic Health Examination : Selection of Manageable Diseases and Evaluation of the Sensitivity and Specificity (건강진단 대상질환 선정 및 건강진단의 정확성 평가)

  • Yu, Seung-Hum;Roh, Jae-Hoon;Lee, Hee-Jong;Jung, Sang-Hyuk
    • Journal of Preventive Medicine and Public Health
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    • v.22 no.1 s.25
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    • pp.45-50
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    • 1989
  • The purpose of this study was to select the manageable diseases which are prevalent in Korea for periodic health examinations and to evaluate the sensitivity and specificity of periodic health examination in detecting these diseases. The data was derived from reimbursement data of the Korea Medical Insurance Corporation over a two year period (April 15, 1986 to April 14,1988) and interviews with Yonsei Medical School professors. This study demonstrated that: 1. The manageable diseases which were selected for periodic health examinations are pulmonary tuberculosis, viral hepatitis, diabetes mellitus, syphilis groups, essential hypertension, renal disease groups, and iron deficiency anemia. 2. The sensitivity of the health screening for each disease was as follows: pulmonary tuberculosis 51.5%, viral hepatitis 60.3%, diabetes mellitus 64.7%, syphilis groups 63.3%, essential hypertension 49.9%, renal disease groups 44.0%, and iron deficiency anemia 80.9%. We conclude that peiodic health esaminations should focus on the manageable diseases that we have defined. The number of items in periodic health screening tests and hospital quality control should be increased for the diseases with a demonstrated low sensitivity.

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The Effects of Mothers' Reading and Teacher's Sensitivity and Permissiveness on 4-and 5-year-olds' Verbal and Numerical Abilities in Low-income Families - The Analysis of FACES Data in the U.S. to Develop Intervention Programs for Low-Income Families - (어머니의 책읽기와 유아교사의 민감성 및 수용성이 저소득 가정 유아의 어휘력과 수리력에 미치는 영향 - 성, 연령, 기질 및 어머니의 앙육행동과 보육경험을 중심으로 -)

  • Chang, Young-Eun;Lee, Soak-Jung;Lee, Kang-Yi
    • Journal of the Korean Home Economics Association
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    • v.46 no.1
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    • pp.117-129
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    • 2008
  • In present study, using 1572 low-income families and 266 Head Start teachers from Family and Child Experiences Survey (FACES) in the U.S., we examined the effects of mothers' reading and the characteristics of interaction between teacher-child interaction on 4-and 5-year-olds' cognitive development represented by their verbal and numerical abilities. Frequencies of mothers' reading at home consistently predicted higher scores of children's Peabody Picture Vocabulary Test and Woodcock Johnson Applied Problems. Teachers' sensitivity and permissiveness in their interactions with children in classroom were positively related to children's verbal abilities and teachers' sensitivity predicted better numerical abilities of children after controlling for mothers' reading and the characteristics of family and teacher. The findings shed light on the contributions of teacher behaviors and familial factors to children's cognitive development calling for attention to the need for parent education on cognitively stimulating family environments and continuing education for early childhood teachers focusing on quality interactions with young children.