Littérature scientifique sur le sujet « Galois closure »

AbstractWe consider the problem of whether the norm one torus defined by a finite separable field extensionK/kis stably (or retract) rational overk. This has already been solved for the case whereK/kis a Galois extension. In this paper, we solve the problem for the case whereK/kis a non-Galois extension such that the Galois group of the Galois closure ofK/kis nilpotent or metacyclic.

AbstractWe consider the problem of whether the norm one torus defined by a finite separable field extension K/k is stably (or retract) rational over k. This has already been solved for the case where K/k is a Galois extension. In this paper, we solve the problem for the case where K/k is a non-Galois extension such that the Galois group of the Galois closure of K/k is nilpotent or metacyclic.

AbstractWe construct a Galois connection between closure and interior operators on a given set. All arguments are intuitionistically valid. Our construction is an intuitionistic version of the classical correspondence between closure and interior operators via complement.

Preclones are described as the closed classes of the Galois connection induced by a preservation relation between operations and matrix collections. The Galois closed classes of matrix collections are also described by explicit closure conditions.

Philosophiae Doctor - PhD
Categorical closure operators were introduced by Dikranjan and Giuli in [DG87] and then developed by these authors and Tholen in [DGT89]. These operators have played an important role in the development of Categorical Topology by introducing topological concepts, such as connectedness, separatedness and compactness, in an arbitrary category and they provide a uni ed approach to various mathematical notions. Motivated by the theory of these operators, the categorical notion of interior operators was introduced by Vorster in [Vor00]. While there is a notational symmetry between categorical closure and interior operators, a detailed analysis shows that the two operators are not categorically dual to each other, that is: it is not true in general that whatever one does with respect to closure operators may be done relative to interior operators. Indeed, the continuity condition of categorical closure operators can be expressed in terms of images or equivalently, preimages, in the same way as the usual topological closure describes continuity in terms of images or preimages along continuous maps. However, unlike the case of categorical closure operators, the continuity condition of categorical interior operators can not be described in terms of images. Consequently, the general theory of categorical interior operators is not equivalent to the one of closure operators. Moreover, the categorical dual closure operator introduced in [DT15] does not lead to interior operators. As a consequence, the study of categorical interior operators in their own right is interesting.

La thèse se situe dans le domaine de l'analyse latticielle de données dans la situation, très générale, ou des objets de nature diverse sont décrits par des variables de types divers ; on fait simplement l'hypothèse (réaliste) selon laquelle chaque variable prend ses valeurs dans un treillis. Les problèmes de traitement de telles données (extraction de connaissance) reviennent souvent à chercher à obtenir des familles de Moore de type particulier, par exemple arborescent, et donc à imposer des contraintes structurelles. Dans ce cadre, nous étudions d'abord les familles de Moore particulières que sont les hiérarchies, dont nous caractérisons la base canonique d'implications. Pour ce faire, nous introduisons un nouveau type de relations binaires sur les parties d'un ensemble, appelées (\em relations d'emboitement). Nous les mettons en correspondance bi-univoque avec les familles de Moore quelconques, établissons leur lien avec l'une des relations flèche, et revenons sur leurs propriétés dans le cas hiérarchique, ou elles sont d'abord apparues. Dans une seconde partie, nous nous intéressons à la correspondance de Galois associée à un tableau binaire (auquel les données du type indiqué ci-dessus peuvent toujours être ramenées). Nous examinons alors les contraintes à imposer à un tableau binaire pour que les fermés obtenus appartiennent à des familles de Moore prescrites, ou de type voulu. On obtient alors des relations binaires dites (\em bifermées). Etant donnés deux espaces de fermeture $(E, \varphi)$ et $(E', \varphi')$, une relation est bifermée si toute ligne de sa représentation matricielle correspond à un fermé par $\varphi$, et toute colonne à un fermé par $\varphi'$. Nous établissons l'isomorphisme entre l'ensemble des relations bifermées et celui des correspondances de Galois entre les deux treillis de fermés induits par $\varphi$ et $\varphi'$. Dans le cas fini, on en déduit des algorithmes efficaces pour l'ajustement d'une correspondance de Galois à une application quelconque entre deux treillis, ou pour le calcul du supremum de deux polarités. Dans une troisième partie, nous appliquons les résultats précédents à l'étude de l'introduction de contraintes classificatoires sur un tableau de données. Nous revenons sur divers usages des correspondances de Galois (ou des couples application résiduée / résiduelle) dans les modèles et les méthodes de la classification. Ceux-ci sont revisités dans l'optique d'une présentation unifiée fondée sur les bifermées, et, en prenant en compte les résultats de la première partie, des voies sont tracées pour la définition de nouvelles méthodes. Ces parties sont précédées d'une synthèse sur les treillis et les correspondances de Galois.

We deal with several problems on the surfaces obtained as second symmetric products of smooth projective curves. In particular, we treat both some attempts at extending the notion of gonality for curves and some classical problems, as the study of the ample cone in the Néron-Severi group. Moreover, we develop a family of examples of Lagrangian surfaces having particular topological properties.

South Arabian kingdoms based their wealth and power on agriculture and the export of incense and other aromatics so much appreciated in the ancient world. After Aelius Gallus’ campaign against Arabia Felix in 25–24 BC, Roman trade by sea with the region greatly increased compared to the overland caravan routes. This chapter summarizes the political situation in Arabia Felix in those times through the analysis of archaeological, historical, and numismatic evidence and focuses on the harbours and mooring places along the Yemenite and Omani coasts. Italian underwater research at Qanaʾ discovered the ancient anchorage, with ceramics dating between the first and the end of the sixth century AD, with a higher percentage before the fourth century AD. Typological and petrological study suggests the close involvement of the Arabian Peninsula in the web of trade routes that connected the Roman world via the Red Sea with India, and the Persian Gulf.

According to the chronicler Edward Hall, the execution of Sir Thomas More, who was sentenced to die on the gallows for refusing to acknowledge the Royal Supremacy, was characterized by a characteristically frivolous lack of decorum on the part of More himself, most notably on the scaffold itself. Both More’s evangelical opponents and his catholic allies noted his merry disposition. This article examines how the ideas of mirth and folly are woven through both More’s public career and the life of his close contemporary and nephew, the Catholic writer and playwright John Heywood. It considers the two men’s adoption and adaptation of classical and medieval notions of foolishness and comedy for their own ends in the dangerous years of Henry VIII’s Reformation. To understand More’s alleged lapse in judgment during his own execution and what this might suggest about the uses of mirth in pre-modern culture more generally, the article analyzes it in the context of his attitude towards theater and hisUtopiaas a satire for and of humanists.

Although it is easy to read our patchy evidence about Columbanus as depicting a lone Irish figure with his deviant Easter tradition battling against a continental ecclesiastical hierarchy comprising bishops and the pope, this paper’s close reading and contextualization of the evidence provides a more nuanced picture. It reveals extensive common ground between the high Christian standards of both Columbanus and Gregory the Great, over against the laxity of the Gallic episcopate, and then focuses on the issue of “shunning,” or withholding oneself from relations with Christians one perceives as sinful, although they have not been excommunicated. A second section examines the Insular background to this, focusing on Gildas’s writings. Finally the third section turns to Columbanus’s dealings with the Merovingians, using the Insular tradition of shunning as a way of re-reading Jonas’s account of how relations between Columbanus and the royal court soured, ending in his exile. Encounters between Columbanus and those with whom he came into contact on the continent have been characterized as confrontation and controversy, reflecting one important aspect of his relations with leading figures. This perception of Columbanus arises from the patchy nature of historical sources. This chapter interrogates the few available sources and tries to place them in context and understand the issues surrounding them. First it investigates his relationship with Gregory the Great, raising the issue of “shunning,” or withholding oneself from relations with Christians one perceives as sinful, although they have not been excommunicated. Then it turns to Columbanus’s dealings with the Merovingians leading up to his exile, using the awareness of shunning as a way of re-reading Jonas’s account of how relations between Columbanus and the royal court soured, ending in his exile.

The Department of Energy mandated the termination of the Integral Fast Reactor (IFR) Program, effective October 1, 1994. To comply with this decision, Argonne National Laboratory-West (ANL-W) prepared a plan providing detailed requirements to maintain the Experimental Breeder Reactor-II (EBR-II) in a radiologically and industrially safe condition, including removal of all irradiated fuel assemblies from the reactor plant, and removal and stabilization of the primary and secondary sodium, a liquid metal used to transfer heat within the reactor plant. The EBR-II is a pool-type reactor. The primary system contained approximately 325 m3 (86,000 gallons) of sodium and the secondary system contained 50 m3 (13,000 gallons). In order to properly dispose of the sodium in compliance with the Resource Conservation and Recovery Act (RCRA), a facility was built to react the sodium to a solid sodium hydroxide monolith for burial as a low level waste in a land disposal facility. Deactivation of a liquid metal fast breeder reactor (LMFBR) presents unique concerns. Residual amounts of sodium remaining in circuits and components must be passivated, inerted, or removed to preclude future concerns with sodium-air reactions that could generate potentially explosive mixtures of hydrogen and leave corrosive compounds. The passivation process being implemented utilizes a moist carbon dioxide gas that generates a passive layer of sodium carbonate/sodium bicarbonate over any quantities of residual sodium. Tests being conducted will determine the maximum depths of sodium that can be reacted using this method, defining the amount that must be dealt with later to achieve RCRA clean closure. Deactivation of the EBR-II complex is on schedule for a March, 2002, completion. Each system associated with EBR-II has an associated layup plan defining the system end state, as well as instructions for achieving the layup condition. A goal of system-by-system layup is to minimize surveillance and maintenance requirements during the interim period between deactivation and decommissioning. The plans also establish document archival of not only all the closure documents, but also the key plant documents (P&IDs, design bases, characterization data, etc.) in a convenient location to assure the appropriate knowledge base is available for decommissioning, which could occur decades in the future.

Abstract In this study, a segment of water conveyance system at a chemical manufacturing facility is under investigation. The pipe segment under investigation conveys a daily average flow of five million gallons of water per day (MGD) from the river to a water treatment plant. The exact age of the pipe system is unknown as limited construction or maintenance information exists. The study area is a pipe segment near the treatment plant where three flow restrictions exist within a 30-foot distance bounded by a T-junction and a water filtration plant. These restrictions include two self-actuated butterfly valves and an orifice plate on a 16-inch diameter steel pipe, buried approximately three feet below ground surface. When standing in the study area, heavy vibrations are felt at the ground surface. The valves and orifice plate are to control flowrate and reduce pressure from 80 PSI to 45PSI as the flow enters the water treatment plant. Flow restrictions in close proximity can cause cavitation, water hammer and other flow phenomena within a pipe system. This can result in excessive wear of the pipe’s inner walls and valves which may compromise the structural integrity and/or function of the system. Computational fluid dynamics (CFD) software is a useful tool for determining if the conditions for the various flow phenomena are present in a system. The flow characteristics were numerically calculated in MATLAB then computationally modeled in AFT Fathom. The purpose of the numerical analysis was to describe the stability of the fluid flow at discrete points in the pipe network and identify the network segments with significantly unstable flow profiles. The purpose of the AFT Fathom CFD model purpose was to provide a continuous simulation of the flow stability in the pipe segment and provide a more robust description of the flow profiles in the network. While Fathom cannot explicitly predict cavitation or water hammer, the kinematic parameters produced by the Fathom model and the physical conditions observed in the study indicate that water hammer is likely occurring.

The Westinghouse Small Modular Reactor (SMR) incorporates an integral pressurized water reactor (iPWR) design in which all components associated with the nuclear steam supply system are housed within one pressure vessel. The Westinghouse SMR design also utilizes many of the key features from the AP1000® plant, including passive safety systems. The Westinghouse SMR will be fueled by a derivative of the successful 17×17 Robust Fuel Assembly (RFA) product. An 89 assembly core with an active height of 8 feet will provide a 24 month operating cycle with a power output of 800 MWt. Derived from the AP1000 plant and adapted to operate inside the reactor pressure vessel, 37 control rod drive mechanisms provide reactor shutdown and reactivity control capabilities. Eight seal less pumps provide a nominal reactor coolant flow of 100,000 gallons per minute. An innovative evolution of a straight tube steam generator produces a saturated mixture that is delivered to a steam separating drum located outside of the containment vessel. The steam generator along with the integral pressurizer is attached to the reactor vessel with a single closure flange located near the center of gravity of the reactor assembly and is designed to be removed during refueling operations. Like the AP1000 plant, the Westinghouse SMR relies on the natural forces of gravity and natural circulation to provide core and containment cooling during accident conditions. The passive cooling systems provide sufficient heat removal for seven days without the need for offsite AC power sources. The Westinghouse SMR also includes traditional active components such as diesel generators and pumps; however these components are not required for the safe shutdown of the plant. At a diameter of 32 feet, approximately 25 of the Westinghouse SMR containment vessels can fit within the envelope of the AP1000 containment building. This compact containment will be completely submerged in water during power operation providing a heat sink for postulated accidents. For protection against external threats, the containment vessel and plant safety systems are located below ground level. At approximately one fifth the net electrical output of the AP1000 plant, the Westinghouse SMR is designed to address infrastructure challenges associated with replacing America’s aging fossil fuel plants by providing a safe, clean and reliable energy source. The challenges associated with economies of scale are offset with a compact and simplified plant design, rail shippable components and modular construction.

Due to increasing energy costs and emissions restrictions, many industries are paying closer attention to the energy required to keep their equipment operating. Parasitic losses in power such as those due to the drag produced by contacting lip seals that are found in a variety of rotating equipment can significantly add to the total operating costs of that equipment. In mobile industries (railroad, heavy truck, and automotive), these losses can significantly affect the amount of fuel consumed and emissions produced. Power losses due to seal drag are also accompanied with frictional heat and wear which can degrade components and lead to maintenance costs to service or replace these components. To address these issues for the railroad industry, Timken has developed a non-contacting seal for use in railroad bearings. A review is given of the design and development of a non-contacting labyrinth seal for railroad bearing applications. The seal has been qualified by the Association of American Railroads (AAR) for use in North America freight car service and is currently the only non-contacting seal in operation for this market. The unique design of the labyrinth pathway allows for zero seal drag with exceptional grease retention and contaminant exclusion capabilities as compared to contacting elastomer lip seals that are typical for this industry. Experimental test performance of this seal will be compared to other seals that are currently used in this industry. Operating torque reductions of 10–30 in-lb per seal achieved through this technology can lead to fuel savings on the order of hundreds of thousands of gallons per year corresponding to the elimination of thousands of tons of emissions due to the reduced fuel usage in the U.S. alone. These savings can be passed directly to railroads and freight car owners as well as the general population with lower operating costs, increased reliability, longer service life, and reduced emissions.

Hakka emigration has created many smaller communities worldwide; where some groups continued their migratory journey. One such example is the Hakkas, who first migrated to Calcutta and then moved on to Vienna and Toronto, clustering in a close-knit social network. In various sessions, Viennese Hakkas of all age groups were interviewed for their lifestories and linguistic practices. (a) The linguistic competence of the migrants includes Hakka, English and Indian (Hindi, Ben¬gali) but often rather little German; Hakka is important at the workplace (Chinese restaurants) and is transmitted in families; Indian helps establish professional relationships with Indian migrants. (b) The social network is rather closed to Hakka friends from Calcutta or from other places. All Hakkas closely cooperate and usually have only few outside contacts. They consider Calcutta as their old homeland to which they return for Chinese New Year. (c) The younger generation consists of weak speakers of Hakka who are fully integrated into Austrian culture, but also maintain contacts to Toronto and love to visit friends and family in India. To conclude, the Indian Hakkas of Vienna are an interesting example of a two-step migration which first converted some Chinese into Indians, and then planted this Indian subgroup into Europe.

A certain nuclear power plant uses a siphon to bring cooling water into the plant during emergency operations. This siphon was “hardened” by adding a nuclear grade vacuum system to the siphon high points. A float valve, sized for the required air flow rate, was used to prevent water carryover into the vacuum system. In order to pass the required flow rate, the valve’s orifice size would be the largest produced by any manufacturer to date. Initial system testing revealed that the valve was not fully opening due to the high vacuum and the design of the valve opening mechanism. Analysis and testing developed a solution to the opening problem. However, a new problem was introduced — excessive liquid carryover. The liquid carryover rate was estimated at 6 gallons per minute. The liquid carryover was postulated to be due to droplet entrainment as high velocity air bubbles entered the valve body, ruptured the air-water interface, and carried some of the resultant droplets through the valve outlet as the valve opened due to falling water level. Additionally, valve operating mechanism changes resulted in it responding slower. Using information learned from modifying the original valve, a new valve design was conceived that would be based on the following 3 principles: 1) liquid momentum must cause it to separate from the air upon entrance into the valve body; 2) enough distance and space must exist inside the body to allow gravity to act upon any liquid droplets to allow them to fall back into the liquid pool instead of being carried out of the valve toward the vacuum system; 3) valve operating mechanism must respond quickly enough to close the valve upon rapid liquid influx. The valve manufacturer reviewed the conceptual design and produced a prototype. The prototype valve was successfully tested with zero water carryover plus better flow versus pressure loss performance than the original valve. The valve also functioned acceptably during shaker table testing to simulate earthquake conditions.

Diesel fuel carriage in locomotives, while safe in normal operational conditions, presents a potential hazard in the event of serious accident or derailment. Development of an effective mitigation method against this hazard requires an understanding of operational conditions that lead to fuel spill and fire. This paper describes a study of fire hazard stemming from rail accidents and potential approaches to mitigation. Data for the study was obtained from a large sample of National Transportation Safety Board (NTSB) investigation reports for accidents involving both freight and passenger locomotive accidents over a 10-year period. Approximately 25% of the events reviewed resulted in fuel release. In addition, of the events that resulted in fuel loss, a large majority (almost 70%) resulted in fire. Most cases with major fires led to loss of life and/or property, including destruction of multiple locomotives. Typical road locomotives carry 3,000–4,500 gallons of diesel fuel during normal operation. As the locomotive consumes fuel, large volumes are available for vapor generation within the tank. In a post-collision scenario, the vapor that vents to the atmosphere at temperatures close to flash point of the fuel presents a significant fire hazard. Further, flammable mists can be generated by the sprays that develop due to fuel leaks from the post-impact movement of a train. Previous laboratory tests on a scaled tank demonstrated that fire in a fuel-rich vapor can flash back inside the tank causing an explosion or a large fire. This paper also assesses potential technologies to prevent or mitigate fire hazards in locomotive fuel tanks. These include fuel tank leak prevention or reduction of outflow from breached fuel tanks, monitoring vapor concentration within fuel tanks, and limiting vapor concentrations inside tank to maintain levels below the Lower Explosive Limit (LEL). Potential benefits of the latter method include minimization of pollution from escaping vapor as well as partial recovery of reusable fuel from vapor.

The effects of plug-in hybrid vehicles in New York City could be substantial to the city’s efforts to achieve future climate change goals and environmental initiatives. This study focuses on these effects as they correlate to the energy supply system, transportation network, and air quality control. To accomplish this analysis a variety of techniques were used to model the transportation and electric networks around New York City. The transportation system is modeled through close manipulation of U.S Census Data collected in 2000 and 2003 in which citizens were asked questions pertaining to their daily journeys to work. The power grid for the Northeast Power Coordinating Council (NPCC) is modeled using a MATLAB program entitled MATPOWER developed by professors and students at Cornell University. By incorporating real-time load datum, this program has the capability of rendering accurate depictions of changes in power plant loads, emissions, and costs. In addition, the program will distinguish the type of energy used on the margin and locate the geographic region of that energy source. With this capability, the focus of this study surrounded three main objectives: to estimate market growth of PHEVs in the New York metropolitan area, investigate how fuel used to generate power changes with increase in demand, and to analyze the effects on emissions from cars and power plants. Initial analysis indicates that the introduction of plug-in hybrid electric vehicles into the New York City commuter fleet will have a net positive effect on reducing both total emissions and localized emissions around the city’s transportation infrastructure. At an ambitious rate of 20% PHEV penetration, New York could save nearly 625,000 gallons of gasoline per day. This is equivalent to 33,000 barrels of oil. At the current gasoline prices in New York State of $2.087 per gallon, this is a daily savings of $1.3 million dollars per day. In addition, at this penetration the PHEV’s would displace over 29,000 metric tonnes of net carbon dioxide per day.

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,