Relevant bibliographies by topics / Flexible distributions

Academic literature on the topic 'Flexible distributions'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Flexible distributions"

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Arnold, Barry C., and Hon Keung Tony Ng. "Flexible bivariate beta distributions." Journal of Multivariate Analysis 102, no. 8 (September 2011): 1194–202. http://dx.doi.org/10.1016/j.jmva.2011.04.001.

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Quintana, Fernando A., Mark F. J. Steel, and José T. A. S. Ferreira. "Flexible univariate continuous distributions." Bayesian Analysis 4, no. 3 (September 2009): 497–521. http://dx.doi.org/10.1214/09-ba418.

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Fosgerau, Mogens, and Stefan L. Mabit. "Easy and flexible mixture distributions." Economics Letters 120, no. 2 (August 2013): 206–10. http://dx.doi.org/10.1016/j.econlet.2013.03.050.

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Ch, V. Sastry. "Marshall-Olkin Stereographic Circular Logistic Distribution." YMER Digital 21, no. 06 (June 22, 2022): 664–68. http://dx.doi.org/10.37896/ymer21.06/66.

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Marshall and Olkin (1997) proposed an interesting method of adding a new parameter to the existing distributions. The resulting distributions are called the MarshallOlkin distributions, these distributions include the original distributions as a special case and are more flexible and represent a wide range of behavior than the original distributions. In this paper, a new class of asymmetric stereographic circular logistic distribution is introduced by using Marshall-Olkin transformation on stereographic circular logistic distribution (Dattatreyarao et al (2016)), named as Marshall-Olkin Stereographic Circular Logistic Distribution. The proposed model admits closed form density and distribution functions, generalizes the stereographic circular logistic model and is more flexible to model various types of data (symmetric and skew-symmetric circular data). Keywords:Characteristics, Stereographic circular logistic distribution, circular data, Marshall-Olkin transformation, l -axial data.
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Hansen, Christian, James B. McDonald, and Whitney K. Newey. "Instrumental Variables Estimation With Flexible Distributions." Journal of Business & Economic Statistics 28, no. 1 (January 2010): 13–25. http://dx.doi.org/10.1198/jbes.2009.06161.

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Ma, Yanyuan, and Marc G. Genton. "Flexible Class of Skew-Symmetric Distributions." Scandinavian Journal of Statistics 31, no. 3 (September 2004): 459–68. http://dx.doi.org/10.1111/j.1467-9469.2004.03_007.x.

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Tovissodé, Chénangnon Frédéric, Sèwanou Hermann Honfo, Jonas Têlé Doumatè, and Romain Glèlè Kakaï. "On the Discretization of Continuous Probability Distributions Using a Probabilistic Rounding Mechanism." Mathematics 9, no. 5 (March 6, 2021): 555. http://dx.doi.org/10.3390/math9050555.

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Most existing flexible count distributions allow only approximate inference when used in a regression context. This work proposes a new framework to provide an exact and flexible alternative for modeling and simulating count data with various types of dispersion (equi-, under-, and over-dispersion). The new method, referred to as “balanced discretization”, consists of discretizing continuous probability distributions while preserving expectations. It is easy to generate pseudo random variates from the resulting balanced discrete distribution since it has a simple stochastic representation (probabilistic rounding) in terms of the continuous distribution. For illustrative purposes, we develop the family of balanced discrete gamma distributions that can model equi-, under-, and over-dispersed count data. This family of count distributions is appropriate for building flexible count regression models because the expectation of the distribution has a simple expression in terms of the parameters of the distribution. Using the Jensen–Shannon divergence measure, we show that under the equidispersion restriction, the family of balanced discrete gamma distributions is similar to the Poisson distribution. Based on this, we conjecture that while covering all types of dispersions, a count regression model based on the balanced discrete gamma distribution will allow recovering a near Poisson distribution model fit when the data are Poisson distributed.
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SHANG, JEN S., and PANDU R. TADIKAMALLA. "MODELING FINANCIAL SERIES DISTRIBUTIONS: A VERSATILE DATA FITTING APPROACH." International Journal of Theoretical and Applied Finance 07, no. 03 (May 2004): 231–51. http://dx.doi.org/10.1142/s0219024904002475.

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The empirical distribution of common stock returns is a subject of interest to many researchers, as it often determines the validity of theoretical models proposed in the economics and finance studies. This paper brings to the attention the availability of two flexible systems of distributions for fitting data: the Johnson system of distributions and the Tadikamalla–Johnson system of distributions. We explore the feasibility of fitting the empirical distributions of several financial series to these two systems of distributions. Both systems of distributions are highly flexible and capable of accommodating all possible skewness and kurtosis values. The probability density function and the cumulative distribution function take on simple closed forms and appropriate transformations of the data lead to normal/logistic distributions. In addition, the parameter estimation procedures are easy to implement. When the results are compared with those of other data fitting models, in all cases tested, the proposed distributions provide a good fit to the empirical distribution of data.
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Alkhairy, Ibrahim, Humaira Faqiri, Zubir Shah, Hassan Alsuhabi, M. Yusuf, Ramy Aldallal, Nicholas Makumi, and Fathy H. Riad. "A New Flexible Logarithmic-X Family of Distributions with Applications to Biological Systems." Complexity 2022 (August 30, 2022): 1–15. http://dx.doi.org/10.1155/2022/7845765.

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Probability distributions play an essential role in modeling and predicting biomedical datasets. To have the best description and accurate prediction of the biomedical datasets, numerous probability distributions have been introduced and implemented. We investigate a novel family of lifetime probability distributions to represent biological datasets in this paper. The proposed family is called a new flexible logarithmic- X (NFLog- X ) family. The suggested NFLog- X family is obtained by applying the T- X method together with the exponential model having the PDF m t = e − t . Based on the NFLog- X approach, a three parameters probability distribution, namely, a new flexible logarithmic-Weibull (NFLog-Wei) distribution is introduced. The method of maximum likelihood estimation is adopted for estimating the parameters of the NFLog- X family. In the end, we examine three different biological datasets in order to give a thorough numerical research that illustrates the NFLog-Wei distribution. Comparisons are made between the analytical goodness-of-fit metrics of the suggested distribution. We made comparison with the (i) alpha power transformed Weibull, (ii) exponentiated Weibull, (iii) Weibull, (iv) flexible reduced logarithmic-Weibull, and (v) Marshall–Olkin Weibull distributions. After performing the analyses, we observe that the proposed method outclassed other competitive distributions.
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Smith, Valerie A., and John S. Preisser. "Direct and flexible marginal inference for semicontinuous data." Statistical Methods in Medical Research 26, no. 6 (September 1, 2015): 2962–65. http://dx.doi.org/10.1177/0962280215602290.

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The marginalized two-part (MTP) model for semicontinuous data proposed by Smith et al. provides direct inference for the effect of covariates on the marginal mean of positively continuous data with zeros. This brief note addresses mischaracterizations of the MTP model by Gebregziabher et al. Additionally, the MTP model is extended to incorporate the three-parameter generalized gamma distribution, which takes many well-known distributions as special cases, including the Weibull, gamma, inverse gamma, and log-normal distributions.
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Dissertations / Theses on the topic "Flexible distributions"

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Haynes, Michele Ann. "Flexible distributions and statistical models in ranking and selection procedures with applications." Thesis, Queensland University of Technology, 1998.

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Carlsson, Daniel, and Johan Dvärsäter. "Flexibel Fysisk Distribution." Thesis, Linköping University, Department of Management and Economics, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-857.

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Bakgrund: Vi anser att en framtida utmaning är att bygga in en flexibilitet i den fysiska distributionen. Detta innebär att ett detaljhandelsföretag skall ha möjlighet att växla mellan att stundtals distribuera en och samma produkt via centrallager och stundtals direkt från producent till varuhus i förädlingskedjan, en flexibel fysisk distribution.

Syfte: Syftet är att utröna förutsättningar för och konsekvenser av en flexibel fysisk distribution för de olika aktörerna i en förädlingskedja, i vilken detaljhandelsföretaget besitter en påtaglig maktposition.

Genomförande: Empirisk data har samlats in genom en fallstudie i IKEA:s förädlingskedja.

Resultat: En integrerad förädlingskedja med ett tydligt supply chain synsätt, i vilken samtliga aktörer samarbetar och har incitament till medverkan, utgör en förutsättning för en flexibel fysisk distribution. Vi vill även framhålla vikten av att de produkter i ett detaljhandelsföretags sortiment som säljer bäst och endast de varuhus med störst kapacitet, bör ingå. Om den fysiska distributionen skall kunna växla i en förädlingskedja måste berörda aktörer vidare erhålla en planeringshorisont. Detta implicerar att skiften avseende fysisk distribution måste ske säsongsvis och då företrädesvis med direktleveranser i högsäsong. Den flexibla fysiska distributionen kommer att få konsekvenser gällande lager och därmed kostnader för aktörerna.

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Tsegaye, Seneshaw Amare. "Flexible Urban Water Distribution Systems." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4597.

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With increasing global change pressures such as urbanization and climate change, cities of the future will experience difficulties in efficiently managing scarcer and less reliable water resources. However, projections of future global change pressures are plagued with uncertainties. This increases the difficulty in developing urban water systems that are adaptable to future uncertainty. A major component of an urban water system is the distribution system, which constitutes approximately 80-85% of the total cost of the water supply system (Swamee and Sharma, 2008). Traditionally, water distribution systems (WDS) are designed using deterministic assumptions of main model input variables such as water availability and water demand. However, these deterministic assumptions are no longer valid due to the inherent uncertainties associated with them. Hence, a new design approach is required, one that recognizes these inherent uncertainties and develops more adaptable and flexible systems capable of using their active capacity to act or respond to future alterations in a timely, performance-efficient, and cost-effective manner. This study develops a framework for the design of flexible WDS that are adaptable to new, different, or changing requirements. The framework consists of two main parts. The first part consists of several components that are important in the pre and post--processing of the least-cost design methodology of a flexible WDS. These components include: the description of uncertainties affecting WDS design, identification of potential flexibility options for WDS, generation of flexibility through optimization, and a method for assessing of flexibility. For assessment a suite of performance metrics is developed that reflect the degree of flexibility of a distribution system. These metrics focus on the capability of the WDS to respond and react to future changes. The uncertainties description focuses on the spatial and temporal variation of future demand. The second part consists of two optimization models for the design of centralized and decentralized WDS respectively. The first model generates flexible, staged development plans for the incremental growth of a centralized WDS. The second model supports the development of clustered/decentralized WDS. It is argued that these clustered systems promote flexibility as they provide internal degrees of freedom, allowing many different combinations of distribution systems to be considered. For both models a unique genetic algorithm based flexibility optimization (GAFO) model was developed that maximizes the flexibility of a WDS at the least cost. The efficacy of the developed framework and tools are demonstrated through two case study applications on real networks in Uganda. The first application looks at the design of a centralized WDS in Mbale, a small town in Eastern Uganda. Results from this application indicate that the flexibility framework is able to generate a more flexible design of the centralized system that is 4% - 50% less expensive than a conventionally designed system when compared against several future scenarios. In addition, this application highlights that the flexible design has a lower regret under different scenarios when compared to the conventionally designed system (a difference of 11.2m3/US$). The second application analyzes the design of a decentralized network in the town of Aura, a small town in Northern Uganda. A comparison of a decentralized system to a centralized system is performed, and the results indicate that the decentralized system is 24% - 34% less expensive and that these cost savings are associated with the ability of the decentralized system to be staged in a way that traces the urban growth trajectory more closely. The decentralized clustered WDS also has a lower regret (a difference of 17.7m3/US$) associated with the potential future conditions in comparison with the conventionally centralized system and hence is more flexible.
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Huang, Danguang. "Flexible design of urban water distribution systems." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/2948/.

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Urban water distribution systems (UWDS) are highly inter-connected and under many uncertainties from water demand, pipe roughness, and component failure. Accurate projections of these uncertainties are almost impossible, and thus it may not be a proper method to design the system to meet its performance criteria for the forecasted scenario. The system is designed for the deterministic not for the uncertainties, as a result it may not be efficient or effective to be operated under different future scenarios. Flexible design is shown as a useful strategy to cost-effectively respond to uncertainties because of its consideration of uncertainties in advance, and has been successfully applied in many engineering systems. The objective of flexible design is to identify flexibility sources in UWDS and embed them into the system design to respond to uncertainties. The thesis discussed different terms to define the property of the system to respond to uncertainties and proposed a definition of flexibility for UWDS. It then proposed different measures to indicate flexibility value and introduced an efficient method to handle numerous uncertain parameters in the model. It also develops an efficient method to identify high value flexibility sources based on the Flexibility Index. Finally the thesis presents a flexibility-based optimisation model that enable water engineers to compare different flexible design alternatives and generate optimal solutions. A definition of flexibility in UWDS is proposed to illustrate broadly its property to respond to uncertainties, since it is not so useful, or at least in this thesis to distinguish similar terms to define the property of the system to respond to uncertainties. Identified flexibility sources by the proposed method is not useful for the flexibility-based optimization model to design a system, but it might be a powerful tool to locate the weak points in the system or provide better update options during rehabilitation of the system. The computational efficiency of the proposed flexibility-based optimisation model was demonstrated by dramatic decreasing on the number of the required hydraulic simulation in the case study. Flexible designs in the case study are more expensive than inflexible design, but have better hydraulic performance under uncertainties.
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Nock, Richard William Raymond. "Flexible precision timing instrumentation and quantum key distribution." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658313.

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Time to Digital Conversion (TDC) is a fundamental building block of many applications, such as quantum information experiments, quantum key distribution, laser detection and ranging (LiDAR), bio-medical imaging, digital phase lock loops, and more. As of today, most timing instruments make use of analogue circuitry or application specific integrated circuits to time input events to picosecond resolution and bin size. As such solutions require programmable logic , to perform calibration and communication tasks, there would be a considerable cost and simplification gain obtained in implementing picosecond timing on the same programmable logic Integrated Circuit (IC). In addition to this, fully digital implementation would allow for such technology to enter broader markets. Numerous methods of implementing TDCs in programmable logic already exist. However, they are limited in bin size, linearity, accuracy or exhibit signi- . ficantly long dead times, due to the fixed structure of the Field Programmable Gate Array (FPGA) itself. This work demonstrates a novel ti~ing technique implemented within a low cost off the shelf FPGA that outperforms previously documented techniques in terms of bin size and linearity. A bin size of 1 ps, single shot precision of 17.11 ps , and a differential and integral. non linearity of < 1 has been demonstrated on a Spartan 6 LX75. The technique's performance is comparable to commercially available instruments costing in excess of an order of magnitude more. A flexible firmware and software defined timing platform has been developed, and four instruments have been demonstrated on it. A multi channel ('"'-'30 ps bin size) TDC, Time Correlated Single Photon Counter, coincidence counter and the aforementioned small bin size TDC have all been developed on a common low cost platform, exploiting the re-programmability of FPGAs. This allows for the functionality to be customised and changed at will, even remotely, as functionality is defined by the FPGA's bitfile and associated Personal Computer (PC) software. The use of such instruments is demonstrated, including hardware for two quantum key distribution systems (the Bristol free space system and the reference frame independent demonstration system), a LiDAR system, and in coincidence counting in quantum optics experiments.
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Zhang, Irene Y. (Irene Yun). "Efficient file distribution in a flexible,wide-area file system." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53188.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 63-65).
WheelFS is a wide-area distributed file system designed to help applications cope with the challenges of sharing data over the wide-area network. A wide range of applications can use WheelFS as a storage layer because applications can control various trade-offs in WheelFS, such as consistency versus availability, using semantic cues. One key feature that many applications require from any storage system is efficient file distribution. The storage system needs to be able to serve files quickly, even large or popular ones, and allow users and applications to quickly browse files. Wide-area links with high latency and low throughput make achieving these goals difficult for most distributed storage systems. This thesis explores using pre fetching, a traditional file system optimization technique, in wide-area file systems for more efficient file distribution. This thesis focuses on Tread, a pref etcher for WheelFS. Tread includes several types of pre fetching to improve the performance of reading files and directories in WheelFS: read-ahead pre fetching, whole file prefetching, directory prefetching and a prefetching optimization for WheelFS's built-in cooperative caching. To makes the best use of scarce wide-area resources, Tread adaptively rate-limits prefetching and gives applications control over what and how prefetching is done using WheelFS's semantic cues. Experiments show that Tread can reduce the time to read a 10MB file in WheelFS by 40% and the time to list a directory with 100 entries by more than 80%.
(cont.) In addition, experiments on Planetlab show that using prefetching with cooperative caching to distribute a 10MB file to 270 clients reduces the average latency for each client to read the file by almost 45%.
by Irene Y. Zhang.
M.Eng.
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Lynch, Alastair M. "Low Cost and Flexible Electronics for Quantum Key Distribution and Quantum Information." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520592.

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He, Yujun. "Contribution au réglage de la tension sur un réseau HTA avec producteurs. Apport de la flexibilité de la demande." Thesis, CentraleSupélec, 2015. http://www.theses.fr/2015SUPL0005/document.

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L’intégration des producteurs décentralisés (DG) dans un réseau de distribution peut modifier le profil de tension et influencer le réglage de tension conventionnel. Pour le bon fonctionnement du réseau, le raccordement des DG ainsi que les charges grosses sont limités par le dimensionnement du réseau. Les travaux de cette thèse ont pour but de proposer une approche du réglage de tension dans un réseau de distribution avec producteur, en appuyant sur la flexibilité de la demande. Les moyens de réglage de tension seront constitués du régleur en charge (OLTC), la régulation de DG ainsi que la demande flexible. Une optimisation centralisée de type MINLP est proposée pour coordonner ces moyens de réglage. Il est montré que si les moyens de l’OLTC et de la puissance réactive ne suffissent pas de lever la contrainte de tension, il faut réduire la puissance active de producteur. Pour le gain de producteur, la demande flexible peut être considérée comme une source active. La modulation de « demand response » (DR) utilisant les charges thermiques est alors proposée au réglage de tension. L’effet de rebond est pris en compte pour les charges thermiques afin de ne pas affecter le profil de tension après l’action de DR. Ces travaux permettent d’envisager un réglage de tension plus active dans le réseau intelligent et augmenter la flexibilité du réseau
Growth of distributed generations (DG) in actual distribution networks will bring voltage issues that cannot be fixed by conventional voltage control means. For the sake of network safety, the size of DG and load in a distribution network is limited by the network parameters. The research described in this thesis aims to propose a voltage control strategy on distribution networks using the flexibility of demand. The voltage control means will consist of the on load tap changer (OLTC), the regulation of DG, and flexible demand. A centralized optimization of MINLP type is proposed to coordinate these voltage control means. It shows if it is not able to remove the voltage constraint with OLTC and reactive power regulation, then it must reduce the active power of DG. In order not to reduce active power of DG, the flexible demand is considered as an active source to take part in voltage control. The demand response (DR) modulation using thermal loads is thus proposed for voltage control. For the thermal load, the cold load pick-up (CLPU) effect must be taken into account in order not to affect the voltage profile after DR action. This work allows us to consider a voltage control strategy more active in smart distribution network and improve the flexibility of network
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Bin-Ibrahim, Ahmad Asrul. "Operational planning and optimisation in active distribution systems for flexible and resilient power." Thesis, Durham University, 2018. http://etheses.dur.ac.uk/12872/.

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The electricity network is undergoing significant changes to cater to environmental-deterioration and fuel-depletion issues. Consequently, an increasing number of renewable resources in the form of distributed generation (DG) are being integrated into medium-voltage distribution networks. The DG integration has created several technical and economic challenges for distribution network operators. The main challenge is basically the problem of managing network voltage profile and congestion which is caused by increasing demand and intermittent DG operations. The result of all of these changes is a paradigm shift in the way distribution networks operate (from passive to active) and are managed that is not limited only to the distribution network operator but actively engages with network users such as demand aggregators, DG owners, and transmission-system operators. This thesis expands knowledge on the active distribution system in three specific areas and attempts to fill the gaps in existing approaches. A comprehensive active network management framework in active distribution systems is developed to allow studies on (i) the flexibility of network topology using modern power flow controllers, (ii) the benefits of centralised thermal electricity storage in achieving the required levels of flexibility and resiliency in an active distribution system, and (iii) system resiliency toward fault occurrence in hybrid AC/DC distribution systems. These works are implemented within the Advanced Interactive Multidimensional Modelling Systems (AIMMS) software to carry out optimisation procedure. Results demonstrate the benefit provided by a range of active distribution system solutions and can guide future distribution-system operators in making practical decisions to operate active distribution systems in cost-effective ways.
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Haj-ahmed, Mohammed A. "Protection and Automation of Microgrids for Flexible Distribution of Energy and Storage Resources." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1430694499.

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Books on the topic "Flexible distributions"

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Arrillaga, J. Flexible power transmission--the HVDC options. Hoboken, NJ: John Wiley, 2007.

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Wassenhove, Luk N. van. Strategic marketing, production, and distribution planning of an integrated manufactureing system. Fontainebleau: INSEAD, 1992.

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Kuhmonen, Mika. The effect of operational disturbances on reliability and operation time distribution of NC-machine tools in FMS. Lappeenranta: Lappeenranta University of Technology, 1997.

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New marketing strategies: Evolving flexible processes to fit market circumstances. London: Thousand Oaks, Calif., 1999.

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Inc, ebrary, ed. FACTS controllers in power transmission and distributio. New Delhi: New Age International (P) Ltd., Publishers, 2007.

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Rosen, I. Gary. Spline-based Rayleigh-Ritz methods for the approximation of the natural modes of vibration for flexible beams with tip bodies. Hampton, Va: Institute for Computer Applications in Science and Engineering, NASA Langley Research Center, 1985.

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Ji, Haoran, Peng Li, and Chengshan Wang. Flexible Distribution Networks. Elsevier, 2023.

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Cookson, Richard, Susan Griffin, Ole F. Norheim, and Anthony J. Culyer, eds. Distributional Cost-Effectiveness Analysis. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198838197.001.0001.

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Distributional cost-effectiveness analysis aims to help healthcare and public health organizations make fairer decisions with better outcomes. Standard cost-effectiveness analysis provides information about total costs and effects. Distributional cost-effectiveness analysis provides additional information about fairness in the distribution of costs and effects—who gains, who loses, and by how much. It can also provide information about the trade-offs that sometimes occur between efficiency objectives such as improving total health and equity objectives such as reducing unfair inequality in health. This is a practical guide to a flexible suite of economic methods for quantifying the equity consequences of health programmes in high-, middle-, and low-income countries. The methods can be tailored and combined in various ways to provide useful information to different decision makers in different countries with different distributional equity concerns. The handbook is primarily aimed at postgraduate students and analysts specializing in cost-effectiveness analysis but is also accessible to a broader audience of health sector academics, practitioners, managers, policymakers, and stakeholders. Part I is an introduction and overview for research commissioners, users, and producers. Parts II and III provide step-by-step technical guidance on how to simulate and evaluate distributions, with accompanying hands-on spreadsheet training exercises. Part IV concludes with discussions about how to handle uncertainty about facts and disagreement about values, and the future challenges facing this young and rapidly evolving field of study.
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Li, Peng, Haoran Ji, Yang Mi, Hao Yu, Yue Zhou, and Nian Liu, eds. Flexible and Active Distribution Networks. Frontiers Media SA, 2021. http://dx.doi.org/10.3389/978-2-88971-125-3.

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Arrillaga, Jos, Y. H. Liu, and Neville R. Watson. Flexible Power Transmission: The HVDC Options. Wiley, 2007.

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Book chapters on the topic "Flexible distributions"

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McLachlan, Geoffrey J., and Sharon X. Lee. "Flexible Modelling via Multivariate Skew Distributions." In Communications in Computer and Information Science, 57–67. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-15-1960-4_4.

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Fasola, Salvatore, and Mariangela Sciandra. "New Flexible Probability Distributions for Ranking Data." In Studies in Classification, Data Analysis, and Knowledge Organization, 117–24. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-17377-1_13.

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Baz, Juan, Diego García-Zamora, Irene Díaz, Susana Montes, and Luis Martínez. "Flexible-Dimensional EVR-OWA as Mean Estimator for Symmetric Distributions." In Information Processing and Management of Uncertainty in Knowledge-Based Systems, 11–24. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08971-8_2.

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Azzalini, Adelchi. "Flexible Distributions as an Approach to Robustness: The Skew-t Case." In Recent Advances in Robust Statistics: Theory and Applications, 1–16. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-3643-6_1.

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SenGupta, Ashis, Kunio Shimizu, Seng Huat Ong, and Radhakanta Das. "A Flexible Family of Mixed Distributions for Discrete Linear and Continuous Circular Random Variables." In Methodology and Applications of Statistics, 365–81. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-83670-2_17.

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van Rhoon, G. C., A. Ameziane, and P. J. M. Rietveld. "Accurate Quantitative Measurement of E-Field Distributions in “Solid” Phantoms Using a Flexible Schottky Diode Sheet." In Sensor Technology 2001, 119–24. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0840-2_21.

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Kandala, Bhavannarayana, and Sudha Vemaraju. "Flexible Distribution Strategies in Network Marketing Companies." In Flexible Systems Management, 51–70. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-2834-9_4.

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Lahri, Vijay, and Krishnendu Shaw. "Multi-objective Sustainable Distribution Network Design Under Uncertain Environment." In Flexible Systems Management, 231–43. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1697-7_16.

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Leair, Mark, Douglas Miles, Vincent Schuster, and Michael Wolfe. "Flexible Data Distribution in PGHPF." In Euro-Par’99 Parallel Processing, 418–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/3-540-48311-x_55.

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Swan, Jerry, Eric Nivel, Neel Kant, Jules Hedges, Timothy Atkinson, and Bas Steunebrink. "Introduction." In The Road to General Intelligence, 1–4. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08020-3_1.

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AbstractThe rise of civilization is synonymous with the creation of tools that extend the intellectual and physical reach of human beings [133]. The pinnacle of such endeavours is to replicate the flexible reasoning capacity of human intelligence within a machine, making it capable of performing useful work on command, despite the complexity and adversity of the real world. In order to achieve such Artificial Intelligence (AI), a new approach is required: traditional symbolic AI has long been known to be too rigid to model complex and noisy phenomena and the sample-driven approach of Deep Learning cannot scale to the long-tailed distributions of the real world. In this book, we describe a new approach for building a situated system that reflects upon its own reasoning and is capable of making decisions in light of its limited knowledge and resources. This reflective reasoning process addresses the vital safety issues that inevitably accompany open-ended reasoning: the system must perform its mission within a specifiable operational envelope.
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Conference papers on the topic "Flexible distributions"

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Usta, I. "Robust regression models based on flexible maximum entropy distributions." In International Conference on Quality, Reliability, Risk, Maintenance and Safety Engineering, edited by Y. M. Kantar. Southampton, UK: WIT Press, 2015. http://dx.doi.org/10.2495/qr2mse140421.

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Trols, Andreas, Herbert Enser, Stefan Clara, Wolfgang Hilber, and Bernhard Jakoby. "Optimizing Heater Electrode and Temperature Distributions on Large Scale Sheet Metal Heaters." In 2021 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS). IEEE, 2021. http://dx.doi.org/10.1109/fleps51544.2021.9469852.

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Takizawa, Hiroki, Hideki Aoyama, and Song Cheol Won. "Rapid Estimation of Die and Mold Machining Time Without NC Data by AI Based on Shape Data." In 2020 International Symposium on Flexible Automation. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/isfa2020-9626.

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Abstract Rapid estimation of machining time is necessary for flexible production scheduling and early responses regarding delivery date. It is also important for selecting the most suitable of a factory’s many machine tools. Usually, machining time is estimated based on an NC program. However, this takes time to generate and its estimation accuracy is not ideal because it cannot consider the control characteristics of the machine tool. This study proposes a new method for rapidly estimating die and mold machining time without generating an NC program: inputting curvature and machining depth distributions into AI as color information.
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Kier, Thiemo M., Martin Leitner, Özge Süelözgen, and Manuel Pusch. "An Integrated Flexible Aircraft Model for Optimization of Lift Distributions." In AIAA Scitech 2019 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2019. http://dx.doi.org/10.2514/6.2019-2039.

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Joyee, Erina Baynojir, and Yayue Pan. "Investigation of a Magnetic-Field-Assisted Stereolithography Process for Printing Functional Part With Graded Materials." In 2020 International Symposium on Flexible Automation. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/isfa2020-9650.

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Abstract Additive manufacturing (AM) has many advantages over traditional fabrication techniques, especially for manufacturing sophisticated structures with intricate architecture. Most AM techniques however are often limited to single material with homogeneous properties. To incorporate multi-functionality in AM fabricated parts, researchers have recently paid much attention to multi-material AM techniques which allow locally programmed material properties. Challenges still remain to manipulate material during AM process for getting desired functionalities in fabricated parts. In this study, we present a novel magnetic-field-assisted stereolithography (M-SL) AM technique capable of printing particle-polymer composites with graded material distributions. This study characterizes process parameters for particle trace development and establishes the relationship between the process and printed properties.
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Matsumura, Takashi, Satoshi Arakawa, and Shoichi Tamura. "Study on Adhesion With Stress and Temperature in Drilling of Aluminum Alloy." In 2020 International Symposium on Flexible Automation. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/isfa2020-9633.

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Abstract Aluminum alloys have been widely used for automobile and aircraft parts. In cutting of aluminum alloy, adhesion sometimes occurs to deteriorate surface finish. The study discusses the adhesion characteristics in drilling of aluminum alloy (A7075) with a flat tool at a point angle of 180 degrees. The adhesion volumes on the rake face of the tool were measured in drillings of blind holes for the cutting speeds and the feed rates. Then, the stress and the temperature distributions were estimated in the cutting simulation. In the simulation, the cutting force is predicted in the chip flow model based on the minimum cutting energy. The cutting temperature is analyzed in Finite volume method using the result in the cutting force prediction. The adhesion volumes are associated with the stress and temperature on the rake face. The adhesion volume becomes large in the temperature ranged from 400 to 500 K. The adhesion volume increases with the stress up to 500 MPa.
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Wiczk, Wieslaw, Ignacy Grvczvnski, Michael L. Johnson, and Joseph R. Lakowicz. "Conformational Distributions Of Flexible Molecules From Steady State Fluorescence Energy Transfer." In 1988 Los Angeles Symposium--O-E/LASE '88, edited by Joseph R. Lakowicz. SPIE, 1988. http://dx.doi.org/10.1117/12.945401.

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Shi, Guangyu, Qing Xiao, and Qiang Zhu. "A Study of 3D Flexible Caudal Fin for Fish Propulsion." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-61528.

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This paper is inspired by a recent numerical study (Shoele and Zhu, 2012, “Leading edge strengthening and the propulsion performance of flexible ray fins,” Journal of Fluid Mechanics, Vol. 693, pp. 402–432), which shows that, for a 2D flexible ray replicating the pectoral fins of live fish, undergoing a flapping motion in a viscous fluid, the performance can be significantly improved via the flexibility distribution on the rays. In present study, we investigate the propulsion capability of a 3D caudal fin undergoing a flapping motion. The embedded rays are modeled as linear springs and the soft membrane is modeled as a flexible plate being able to deform in span-wise direction. A finite-volume method based Navier-Stokes solver is used to solve the fluid-structure interaction problem. The present paper focuses on the effects of various distributions of the ray and the ray flexibilities, which can lead to different fin deformations. It is shown that the detailed ray distribution has significant influence on the propulsion performance. By distributing fin rays at the tips rather than the middle of fin, a less power expenditure is observed, leading to higher propulsion efficiency. However, larger thrust force is obtained through distributing the rays at the middle, which is attributed to larger effective flapping amplitude. Additionally, ray flexibilities also play a pivotal role in the thrust generation of the fin.
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Gryczynski, Ignacy, Zygmunt Gryczynski, Wieslaw M. Wiczk, Jozef Kusba, and Joseph R. Lakowicz. "Effect of molecular ordering on distance distributions of flexible donor-acceptor pairs." In OE/LASE '92, edited by Joseph R. Lakowicz. SPIE, 1992. http://dx.doi.org/10.1117/12.58257.

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Yan, Xin, Yabo Wang, Kang Zhang, Xinbo Dai, and Kun He. "Investigations Into Aerodynamic Performance of Turbine Stages With Flexible Shroud Seals." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14329.

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Abstract The present paper utilizes a numerical method to investigate the effect of flexible shroud seals, including the forward bending flexible seals and backward bending flexible seals, on aerodynamic performance of high pressure steam turbine stages. At first, the wear performance of flexible seal is analyzed with the Finite Element Analysis method. It shows that wear in flexible strip is so small that only the installation clearance needs to be considered in operation process. Then, by replacing the labyrinth shroud seals with flexible shroud seals, the aerodynamic efficiency, outlet flow angle distributions, and reaction degree distributions in two-stages are obtained. At three installation clearances, interactions between leakage flow and main flow, as well as the flow patterns in flexible shroud seals, are visualized and also compared with the original design case. The numerical results indicate that turbine stages configured with forward bending flexible shroud seals have a very close aerodynamic performance to those configured with conventional labyrinth shroud seals at the same clearance, whereas the turbine stages configured with backward bending flexible seals have lower total-total isentropic efficiency than those with conventional labyrinth shroud seals. By replacing the conventional labyrinth shroud seals with forward bending flexible shroud seals (at the same clearance), the aerodynamic efficiency, outlet flow angles, limiting streamlines, secondary flow patterns in shroud region and reaction degree distributions in stages are almost not affected. Since the forward bending flexible seal allows relatively smaller installation clearance than the conventional labyrinth seal, application of this kind of seal in rotor blade tip gap is much beneficial to achieve lower leakage rate and higher aerodynamic performance in large power steam turbine stages.
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Reports on the topic "Flexible distributions"

1

Chen, X., J. M. Connors, and C. H. Tong. A flexible method to calculate the distributions of discretization errors in operator-split codes with stochastic noise in problem data. Office of Scientific and Technical Information (OSTI), January 2014. http://dx.doi.org/10.2172/1119920.

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Seljebotn, D. S., O. Certik, A. R. Terrel, A. J. Ahmadia, and C. E. Kees. Flexible Scientific Software Distribution with Hashdist. Fort Belvoir, VA: Defense Technical Information Center, November 2013. http://dx.doi.org/10.21236/ada593659.

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Heymsfield, Ernie, and Jeb Tingle. State of the practice in pavement structural design/analysis codes relevant to airfield pavement design. Engineer Research and Development Center (U.S.), May 2021. http://dx.doi.org/10.21079/11681/40542.

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An airfield pavement structure is designed to support aircraft live loads for a specified pavement design life. Computer codes are available to assist the engineer in designing an airfield pavement structure. Pavement structural design is generally a function of five criteria: the pavement structural configuration, materials, the applied loading, ambient conditions, and how pavement failure is defined. The two typical types of pavement structures, rigid and flexible, provide load support in fundamentally different ways and develop different stress distributions at the pavement – base interface. Airfield pavement structural design is unique due to the large concentrated dynamic loads that a pavement structure endures to support aircraft movements. Aircraft live loads that accompany aircraft movements are characterized in terms of the load magnitude, load area (tire-pavement contact surface), aircraft speed, movement frequency, landing gear configuration, and wheel coverage. The typical methods used for pavement structural design can be categorized into three approaches: empirical methods, analytical (closed-form) solutions, and numerical (finite element analysis) approaches. This article examines computational approaches used for airfield pavement structural design to summarize the state-of-the-practice and to identify opportunities for future advancements. United States and non-U.S. airfield pavement structural codes are reviewed in this article considering their computational methodology and intrinsic qualities.
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Wang, Zhaoyu, and Leigh Tesfatsion. Flexible Service Contracting for Risk Management within Integrated Transmission and Distribution Systems. Office of Scientific and Technical Information (OSTI), December 2020. http://dx.doi.org/10.2172/1870960.

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Loftness, Vivian, Rohini Brahme, Michelle Mondazzi, Edward Vineyard, and Michael MacDonald. Energy Savings Potential of Flexible and Adaptive HVAC Distribution Systems for Office Buildings. Office of Scientific and Technical Information (OSTI), June 2002. http://dx.doi.org/10.2172/795647.

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Bolton, Laura. Global Health Funds and Humanitarian Programming. Institute of Development Studies, September 2022. http://dx.doi.org/10.19088/k4d.2022.144.

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There is a lack of reporting on the connection between Humanitarian Country Team Health Clusters and the three funds (the Global Fund, the Gavi Alliance, and the Global Financing Facility (GFF)), both generally and for the three countries of focus (Mozambique, Uganda, and Nigeria). The Global Fund is noted to partner with the Global Health Cluster but details were not identified within the scope of this report. Global Fund A Global Fund board meeting report and a review of Fund investments in challenging operating environments notes partnering and joining with the Global Health Clusters but does not give detail of specific countries. The Global Fund does not include Mozambique or Uganda in their list of challenging operating environments. There are reports of emergency funding being allocated for refugees in Uganda, and for internally displaced persons (IDPs) in Mozambique. Countries are encouraged to include refugees in their funding requests to the Global Fund. Some Global Fund supported operations for HIV treatment in Mozambique have been interrupted as people receiving treatment fled from violence. Partners in provinces where the displaced are arriving are implementing emergency plans to maintain continuity of care. A Global Fund initiative for removing human-rights barriers to health treatment does not list refugees or IDPs as vulnerable groups for HIV programming. The same initiative in Uganda did specifically support distribution of nets to help prevent malaria. A 2017 audit report on Global Fund grant management in high-risk environments found inadequate early warning mechanisms to identify risk levels of grants. Gavi Alliance Gavi Alliance policy documentation states that a flexible and tailored approach is taken to achieve equity in fragile or emergency situations and for the needs of displaced populations. Requests for flexible support are based on specific needs which must be justified. The policy puts a strong emphasis on ensuring the inclusion of displaced populations. It encourages governments to provide immunisations independent of residency and legal status. They provide extra support where justified for displaced people. Very little information on Gavi activity in the countries of focus for this report was found. Global Financing Facility The GFF 2021-2025 strategy reports offering support in complex humanitarian settings but detail is not included. An earlier report describes GFF support in Nigeria where the Facility were able to finance a targeted project in a short timeframe. Distinction is made between this type of support and emergency support which is not part of the design of the GFF and is unable to quickly release lifesaving funds in emergency situations. The short timeframe funding was provided to support the Nigerian State Health Investment Project where violence had disrupted health services and where health indicators were poor. Mobile health teams were contracted out to hard-to-reach areas. Outreach included psychosocial support.
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Stampini, Marco, Pablo Ibarrarán, Carolina Rivas, and Marcos Robles. Adaptive, but not by design: cash transfers in Latin America and the Caribbean before, during and after the COVID-19 Pandemic. Inter-American Development Bank, November 2021. http://dx.doi.org/10.18235/0003795.

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The socioeconomic crisis associated with the pandemic put cash transfer programs back at the top of the policy agenda. It showed that the Latin American and Caribbean regions income support systems were both fundamental and insufficient. In this paper, we present novel estimates of the coverage and beneficiary distribution of all non-contributory cash transfers both before and during the COVID-19 crisis. The former is useful to show the degree of preparedness of the region. The latter analyzes the magnitude of the policy response. While the literature presents estimates of coverage and leakage of conditional cash transfers and non-contributory pensions, our results are novel because they are the first to analyze coverage and leakage implemented in response to the COVID-19 crisis. In addition, we are the first to expand the focus to all non-contributory cash transfer programs, including those that are quasi-universal and/or unconditional. This is the most appropriate focus when the goal is to assess the ability to provide protection to larger population groups (including the vulnerable) and against transitory poverty caused by systemic shocks (such as pandemic or extreme weather events, which may become more and more frequent due to climate change). Using data from the Inter-American Development Bank “Harmonized Household Surveys from Latin America and the Caribbean”, which now provide a more comprehensive coverage of Caribbean countries, we show that before the pandemic non-contributory cash transfers covered 26% of the population of 17 countries with available data. Average coverage of the extreme poor, moderate poor and vulnerable population was 56%, 43% and 28% respectively. During the crisis, LAC governments implemented 111 new cash transfer interventions, increasing coverage to 34% of the population in 12 countries with available data. Average coverage increased among the moderate poor (50%) and vulnerable population (37%), while it remained unvaried amongst the extreme poor. Moving forward, the countries of the region are called to reform their social protection systems to make them more flexible, efficient, and sustainable, and including strategies that provide protection against shocks. In this way, resilient and responsive social protection systems can contribute to the fight against climate change and support a just transition towards net-zero emission societies. These efforts must also include measures to close the historical coverage gap amongst the poorest.
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Backstrom, Robert, and David Dini. Firefighter Safety and Photovoltaic Systems Summary. UL Firefighter Safety Research Institute, November 2011. http://dx.doi.org/10.54206/102376/kylj9621.

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Under the United States Department of Homeland Security (DHS) Assistance to Firefighter Grant Fire Prevention and Safety Research Program, Underwriters Laboratories examined fire service concerns of photovoltaic (PV) systems. These concerns include firefighter vulnerability to electrical and casualty hazards when mitigating a fire involving photovoltaic (PV) modules systems. The need for this project is significant acknowledging the increasing use of photovoltaic systems, growing at a rate of 30% annually. As a result of greater utilization, traditional firefighter tactics for suppression, ventilation and overhaul have been complicated, leaving firefighters vulnerable to potentially unrecognized exposure. Though the electrical and fire hazards associated with electrical generation and distribution systems is well known, PV systems present unique safety considerations. A very limited body of knowledge and insufficient data exists to understand the risks to the extent that the fire service has been unable to develop safety solutions and respond in a safe manner. This fire research project developed the empirical data that is needed to quantify the hazards associated with PV installations. This data provides the foundation to modify current or develop new firefighting practices to reduce firefighter death and injury. A functioning PV array was constructed at Underwriters Laboratories in Northbrook, IL to serve as a test fixture. The main test array consisted of 26 PV framed modules rated 230 W each (5980 W total rated power). Multiple experiments were conducted to investigate the efficacy of power isolation techniques and the potential hazard from contact of typical firefighter tools with live electrical PV components. Existing fire test fixtures located at the Delaware County Emergency Services Training Center were modified to construct full scale representations of roof mounted PV systems. PV arrays were mounted above Class A roofs supported by wood trusses. Two series of experiments were conducted. The first series represented a room of content fire, extending into the attic space, breaching the roof and resulting in structural collapse. Three PV technologies were subjected to this fire condition – rack mounted metal framed, glass on polymer modules, building integrated PV shingles, and a flexible laminate attached to a standing metal seam roof. A second series of experiments was conducted on the metal frame technology. These experiments represented two fire scenarios, a room of content fire venting from a window and the ignition of debris accumulation under the array. The results of these experiments provide a technical basis for the fire service to examine their equipment, tactics, standard operating procedures and training content. Several tactical considerations were developed utilizing the data from the experiments to provide specific examples of potential electrical shock hazard from PV installations during and after a fire event.
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Backstrom, Robert, and David Backstrom. Firefighter Safety and Photovoltaic Installations Research Project. UL Firefighter Safety Research Institute, November 2011. http://dx.doi.org/10.54206/102376/viyv4379.

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Under the United States Department of Homeland Security (DHS) Assistance to Firefighter Grant Fire Prevention and Safety Research Program, Underwriters Laboratories examined fire service concerns of photovoltaic (PV) systems. These concerns include firefighter vulnerability to electrical and casualty hazards when mitigating a fire involving photovoltaic (PV) modules systems. The need for this project is significant acknowledging the increasing use of photovoltaic systems, growing at a rate of 30% annually. As a result of greater utilization, traditional firefighter tactics for suppression, ventilation and overhaul have been complicated, leaving firefighters vulnerable to potentially unrecognized exposure. Though the electrical and fire hazards associated with electrical generation and distribution systems is well known, PV systems present unique safety considerations. A very limited body of knowledge and insufficient data exists to understand the risks to the extent that the fire service has been unable to develop safety solutions and respond in a safe manner. This fire research project developed the empirical data that is needed to quantify the hazards associated with PV installations. This data provides the foundation to modify current or develop new firefighting practices to reduce firefighter death and injury. A functioning PV array was constructed at Underwriters Laboratories in Northbrook, IL to serve as a test fixture. The main test array consisted of 26 PV framed modules rated 230 W each (5980 W total rated power). Multiple experiments were conducted to investigate the efficacy of power isolation techniques and the potential hazard from contact of typical firefighter tools with live electrical PV components. Existing fire test fixtures located at the Delaware County Emergency Services Training Center were modified to construct full scale representations of roof mounted PV systems. PV arrays were mounted above Class A roofs supported by wood trusses. Two series of experiments were conducted. The first series represented a room of content fire, extending into the attic space, breaching the roof and resulting in structural collapse. Three PV technologies were subjected to this fire condition – rack mounted metal framed, glass on polymer modules, building integrated PV shingles, and a flexible laminate attached to a standing metal seam roof. A second series of experiments was conducted on the metal frame technology. These experiments represented two fire scenarios, a room of content fire venting from a window and the ignition of debris accumulation under the array. The results of these experiments provide a technical basis for the fire service to examine their equipment, tactics, standard operating procedures and training content. Several tactical considerations were developed utilizing the data from the experiments to provide specific examples of potential electrical shock hazard from PV installations during and after a fire event.
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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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