• 제목/요약/키워드: Quantitative methods

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Optimal Design of Robust Quantitative Feedback Controllers Using Linear Programming and Genetic Algorithms

  • Bokharaie, Vaheed S.;Khaki-Sedigh, Ali
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.428-432
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    • 2003
  • Quantitative Feedback Theory (QFT) is one of most effective methods of robust controller design and can be considered as a suitable method for systems with parametric uncertainties. Particularly it allows us to obtain controllers less conservative than other methods like $H_{\infty}$ and ${\mu}$-synthesis. In QFT method, we transform all the uncertainties and desired specifications to some boundaries in Nichols chart and then we have to find the nominal loop transfer function such that satisfies the boundaries and has the minimum high frequency gain. The major drawback of the QFT method is that there is no effective and useful method for finding this nominal loop transfer function. The usual approach to this problem involves loop-shaping in the Nichols chart by manipulating the poles and zeros of the nominal loop transfer function. This process now aided by recently developed computer aided design tools proceeds by trial and error and its success often depends heavily on the experience of the loop-shaper. Thus for the novice and First time QFT user, there is a genuine need for an automatic loop-shaping tool to generate a first-cut solution. In this paper, we approach the automatic QFT loop-shaping problem by using an algorithm involving Linear Programming (LP) techniques and Genetic Algorithm (GA).

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전자 스체클 패턴 간섭법을 이용한 반경방향 대칭 유체의 정량적 가시화 및 물성치 측정에 관한 연구 (A Study on Quantitative Visualization and Measurement of Physical Properties of Radial Symmetric Fluids Using Electronic Speckle Pattern Interferometry)

  • 강영준;채희창;김경석
    • 대한기계학회논문집A
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    • 제26권2호
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    • pp.217-224
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    • 2002
  • It is very important to measure and visualize the changes in the physical properties of fluid flow because this is the foundation of measurement techniques used in aerodynamics, heat transfer, plasma diagnostics, and stress analysis of transparent models. The optical methods are advantageous over probe-based techniques in the optical methods are of high speed, non-contact and are capable of providing full-field results with high spatial resolution. Therefore we propose the electronic speckle pattern interferometry(ESPI) that gives us a solution to overcome those limitations. In this paper the experimental results show qualitative and quantitative visualization of changes in the physical properties of the candle and alcohol lamp with 3D plotting. And we obtained the refractive index, mass density and temperature distribution of fluids. The results clearly show the process of flow phenomena and give the feasibility of quantitative interpretation of gasdynamics.

정자생성 주기법을 이용한 고환독성 평가 필요성과 정량적인 고환독성 평가방법에 대한 고찰 (The Recommended Approaches for the Evaluation of Testicular Toxicity with Awareness of the Spermatogenic Cycle and Quantitative Testicular Toxicity Evaluation Methods)

  • 손우찬;김종춘;유일재
    • Toxicological Research
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    • 제19권2호
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    • pp.83-90
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    • 2003
  • Since histopathological examination was known to be the most sensitive evaluation for testicular toxicity, regulatory authorities have been published the guidelines on practical testicular assay approach. Those guidelines specified details of evaluation including fixation, embedding, stain-ing, histological examination and also seminiferous tubular staging methods. However, there have been confusing understanding among toxicologists and even pathologists on staging theory and its application on industrial testicular toxicity. Guidelines did not intend to conduct quantitative assay with staging but recommended the use of knowledge of staging. To count each tubular stage with statistical analysis is known to be time consuming and labor burdening work but the significance of toxicity has little value. It also has been pointed out that the application of staging theory for longer-term toxicity considered to be lacking of rationale. It could be recommended that qualitative assay with aware-ness of germ cell loss is more efficient method rather than quantitative counting of each tubular stage. Therefore it would be required that comprehensive understanding of testicular toxicity evaluation and the use of testicular staging method.

Quantitative Polymerase Chain Reaction for Microbial Growth Kinetics of Mixed Culture System

  • Cotto, Ada;Looper, Jessica K.;Mota, Linda C.;Son, Ahjeong
    • Journal of Microbiology and Biotechnology
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    • 제25권11호
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    • pp.1928-1935
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    • 2015
  • Microbial growth kinetics is often used to optimize environmental processes owing to its relation to the breakdown of substrate (contaminants). However, the quantification of bacterial populations in the environment is difficult owing to the challenges of monitoring a specific bacterial population within a diverse microbial community. Conventional methods are unable to detect and quantify the growth of individual strains separately in the mixed culture reactor. This work describes a novel quantitative PCR (qPCR)-based genomic approach to quantify each species in mixed culture and interpret its growth kinetics in the mixed system. Batch experiments were performed for both single and dual cultures of Pseudomonas putida and Escherichia coli K12 to obtain Monod kinetic parameters (μmax and Ks). The growth curves and kinetics obtained by conventional methods (i.e., dry weight measurement and absorbance reading) were compared with that obtained by qPCR assay. We anticipate that the adoption of this qPCR-based genomic assay can contribute significantly to traditional microbial kinetics, modeling practice, and the operation of bioreactors, where handling of complex mixed cultures is required.

통제이론(統制理論)과 관리회계(管理會計) (Control Theory and Managerial Accouting)

  • 변용환
    • 산학경영연구
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    • 제1권
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    • pp.249-271
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    • 1987
  • Applicability of control theories to the efficient operation of accounting system is studied in this paper. Since managerial accounting has been developed along the progrees of control theory, management control theories are essential to explain important attributes of diverse accounting system. Basic concept of control is studied in depth and control systems are classified on the base of their special characteristics. And then the applicability of those control methods to accounting systems are discussed based on behavioral as well as management science approach. In the management science approach, accounting control models of production management, inventory management and R&D are designed with its unique quantitative characteristics. It, however, is very difficult to implement quantified control standards on the behavioral management side. Since most of variables considered on behavioral approach are non-quantitative, only discussion of the theoratical definition has been a main issue on previous studies. In this paper, practicability of the behavioral approach to the accounting control system is studied analyzing state variables and behavior variables of the control system. Theoratical base of the discussion are provided from control theories developed in organization theory and Economics. Basic objective of accounting control practice is to control qualitative human behavior represented by quantified figures while quantitative methods are prevailing over general accounting practice. Therefore, this paper tried to develope and integrate accounting control systems applicable to the behavioral management area as well as management science control side.

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The quantitative sensory testing is an efficient objective method for assessment of nerve injury

  • Kim, Young-Kyun;Yun, Pil-Young;Kim, Jong-Hwa;Lee, Ji-Young;Lee, Won
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제37권
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    • pp.13.1-13.7
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    • 2015
  • Background: This study evaluated Somatosensory evoked potentials (SEP), Quantitative sensory testing (QST), and thermography as diagnostic methods for nerve injury. Methods: From 2006 through 2011, 17 patients (mean age: 50.1 years) from ${\bigcirc}{\bigcirc}{\bigcirc}{\bigcirc}$ Hospital who sought care for altered sensation after dental implant treatment were identified. The mean time of objective assessment was 15.2 months after onset. Results: SEP of Inferior alveolar nerve(IAN) was $15.87{\pm}0.87ms$ on the normal side and $16.18{\pm}0.73ms$ on the abnormal side. There was delayed N20 latency on the abnormal side, but the difference was not statistically significant. In QST, the abnormal side showed significantly higher scores of the current perception threshold at 2 KHz, 250 Hz, and 5 Hz. The absolute temperature difference was $0.55^{\circ}C$ without statistically significance. Conclusion: These results indicate that QST is valuable as an objective method for assessment of nerve injury.

Event-specific Detection Methods for Genetically Modified Maize MIR604 Using Real-time PCR

  • Kim, Jae-Hwan;Kim, Hae-Yeong
    • Food Science and Biotechnology
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    • 제18권5호
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    • pp.1118-1123
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    • 2009
  • Event-specific real-time polymerase chain reaction (PCR) detection method for genetically modified (GM) maize MIR604 was developed based on integration junction sequences between the host plant genome and the integrated transgene. In this study, 2 primer pairs and probes were designed for specific amplification of 100 and 111 bp DNA fragments from the zSSIIb gene (the maize endogenous reference gene) and MIR604. The quantitative method was validated using 3 certified reference materials (CRMs) with levels of 0.1, 1, and 10% MIR604. The method was also assayed with 14 different plants and other GM maize. No amplification signal was observed in real-time PCR assays with any of the species tested other than MIR604 maize. As a result, the bias from the true value and the relative deviation for MIR604 was within the range from 0 to 9%. Precision, expressed as relative standard deviation (RSD), varied from 2.7 to 10% for MIR604. Limits of detections (LODs) of qualitative and quantitative methods were all 0.1%. These results indicated that the event-specific quantitative PCR detection system for MIR604 is accurate and useful.

Factors Affecting an Application of Environmental Management Accounting: A Case Study of the Automobile Industry in Vietnam

  • TRAN, Ngoc Hung;NGUYEN, Thi Thuy Hanh;NGUYEN, Thi Phuong
    • The Journal of Asian Finance, Economics and Business
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    • 제8권7호
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    • pp.509-516
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    • 2021
  • This study aims to find out and measure the level of factors affecting the applicability of environmental management accounting (EMA) in Vietnamese automobile industry enterprises. Data was collected using both quantitative and qualitative methods. First, in general research, qualitative methodology was used to find out factors (variables) that can impact the possibility of implementing EMA in Vietnamese automobile enterprises. Second, in detailed research, all variables are measured using a quantitative method by collecting data through sampling and sending questionnaires. 500 questionnaires were sent to automobile enterprise managers and only 352 questionnaires met the criteria for the data analysis. The study used a mixed research design approach- a procedure for collecting, analyzing, and "mixing" both quantitative and qualitative research and methods in a single study to understand the research problem. Results show that 7 factors affect the possibility of implementing EMA in Vietnamese automobile industry enterprises. These factors are coercive pressure, normative pressure, mimetic pressure, business environmental uncertainty, environmental strategy, benefits when applying EMA, and task complexity. Based on the results of the study, promoting EMA in the automotive industry should depend mainly on the role of governmental departments.

Analysis of quantitative high throughput screening data using a robust method for nonlinear mixed effects models

  • Park, Chorong;Lee, Jongga;Lim, Changwon
    • Communications for Statistical Applications and Methods
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    • 제27권6호
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    • pp.701-714
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    • 2020
  • Quantitative high throughput screening (qHTS) assays are used to assess toxicity for many chemicals in a short period by collectively analyzing them at several concentrations. Data are routinely analyzed using nonlinear regression models; however, we propose a new method to analyze qHTS data using a nonlinear mixed effects model. qHTS data are generated by repeating the same experiment several times for each chemical; therefor, they can be viewed as if they are repeated measures data and hence analyzed using a nonlinear mixed effects model which accounts for both intra- and inter-individual variabilities. Furthermore, we apply a one-step approach incorporating robust estimation methods to estimate fixed effect parameters and the variance-covariance structure since outliers or influential observations are not uncommon in qHTS data. The toxicity of chemicals from a qHTS assay is classified based on the significance of a parameter related to the efficacy of the chemicals using the proposed method. We evaluate the performance of the proposed method in terms of power and false discovery rate using simulation studies comparing with one existing method. The proposed method is illustrated using a dataset obtained from the National Toxicology Program.

가뭄지수의 적용성 분석을 통한 가뭄의 정량적 표현기법 개발 (Development of Quantitative Drought Representation Methods by Drought Index Application)

  • 정상만;이주헌;김이형;김하용
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2006년도 학술발표회 논문집
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    • pp.1166-1171
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    • 2006
  • Drought is defined by differently for the several scientific and technical fields such as hydrological drought, agricultural drought, meteorological drought, climatological drought, atmospheric drought. A lot of drought indices have been developed to quantify drought severity levels. However these drought indices might be expressed differently as the drought conditions for specific period because the drought severity level is using different types of data on each condition. It is necessary for development of quantative drought representation methods by drought index application. In this research, the reaction to the historical droughts is analyzed after estimation of PDSI, SPI and MSWSI(Modified Surface Water Supply Index) in south korean territory. Lastly the drought representation methods were examiner combining the drought indices by drought indices. The arithmetic mean drought indices that include PDSI, SPI, in yearly basis from 1971 to 2001 and MSWSI in yearly basis from 1974 to 2001 were estimated through the whole nation. The applicability of drought indices are examined based on the observed drought data for national and regional droughts. The result shows that PDSI, SPI(3), SPI(6), and MSWSI have proven to be sensitive enough to the historical drought. The correlation analysis of each drought index was conducted whether they could show the long and short term drought equally. The analysis of how appropriately represent for the historical drought was used for determining for the combined drought index. Consequently, PDSI, SPI(3), SPI(6), and MSWSI have been appeared as suitable indices for the development of quantitative drought representation methods. For the decision of weight on combining PDSI, SPI(3), SPI(6), and MSWSI, drought map was made for eighteen alternative to decide weight. The results showed that PDSI(20%), SPI(3)(60%), SPI(6)(10%), and MSWSI(10%) have been the most well matched weights. Using selected weights of each drought indices and by reconstructing the national mean drought severity on yearly basis, the fact that the year of historical drought is in accordance with the verified one for drought representation. In short, the acquired technique using combined drought index can be used for useful and believable quantitative method of drought analysis.

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