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AbstractBlack kites of the nominal subspecies Milvus migrans migransbreed in Europe and winter regularly in sub-Saharan Africa and the Middle East. As a new phenomenon, black kites with morphological characteristics of the subspecies Milvus migrans lineatusare observed in Europe. Based on observations of black kites in winter 2020/2021 summarized in this paper, based on other recent reports about wintering black kites in Europe and based on juvenile black kite tagged on Crete and tracked for two years, we conclude that hundreds to thousands of black kites are now regularly wintering in south of Europe, and in smaller numbers in other parts of Europe as well as in northern Africa. The growing number of wintering black kites in Europe is apparently caused by members of the population from a hybrid zone between M. m. migransand M. m. lineatusbreeding east of the Urals, i.e. from the area of the European part of Russia. This is consistent with the hypothesis of the spreading of M. m. lineatusand a subsequent hybridization zone between M. m. migransand M. m. lineatusin a westerly direction from Siberia across continental Europe. Moreover, two black kites found dead on Crete were attributed to M. m. lineatusand M. m. migransby cytochrome Bgene sequence analyses. The juvenile black kite with lineatusfeatures tagged on Crete and telemetrically tracked during the next two years moved to the south-western part of Russia during the next two summers, but did not breed. It spent the following two winters at the same landfill in south-western Turkey. It seems that an adaptation to food sources provided by municipal waste landfills is important for black kites wintering in Europe, the Middle East and Morocco.Highlights• Hundreds to thousands of black kites are now regularly wintering in Europe.• The growing number of wintering black kites is caused by birds from a hybrid zone between Milvus migrans migransand M. m. lineatusin eastern Europe.• Municipal waste landfills are important as food sources for black kites wintering in Europe.

Carbon fiber reinforced plastic (CFRP) is extensively used in automotive and aerospace industries with the aim to achieve reduction on emissions by reducing weight. Due to governmental regulations to reduce the environmental impact and to reduce waste, the need for remanufacturing CFRP is becoming an interesting area of application with economic benefits to industry. This is important as manufacturing carbon fiber is a costly process and remanufacturing CFRP is more cost effective and reduces the dependency on virgin materials. Processing CFRP to meet demands, for fast and high-quality cuts, can impose problems for conventional methods. The use of multi-pass scanning technique in laser cutting CFRP is investigated using a 1.5 kW fiber laser with assist gas pressure of 16 bar and gas flow rate of 126 lt/min. Using multi-pass technique, a through cut can be obtained by repeating the beam travel more than once. The advantage of laser cutting when compared with traditional CNC, is the low cost of maintenance over time due to the non-contact nature of the process i.e. no wear of tool at contact area. And due to the small beam spot size of the laser small and complex shapes can be cut. The aim of the paper is to determine how the process performs in terms of cutting speed and fiber damage. Average power was used to carried out experimental tests. A fiber damage below 100 µm with laser cutting speed of 2.5 m/min and above was obtained. Thermal effects were analyzed using scanning electron microscope (SEM) and optical microscope (OM). The fiber damage was further optimized using specialist methods such as double aperture nozzle and trenching. The use of trenching and double aperture further reduces the fiber damage to 10 µm and 50 µm, respectively with laser cutting speed of 7.5 m/min and 3.33 m/min.

ABSTRACTIntroductionHelicobacter pyloricauses dyspepsia, peptic ulcer, and gastric malignancies. Treatments for Helicobacter pyloriare mostly empirical depending on regional antibiotic resistances and the patient’s history and less frequently susceptibility guided. Helicobacter pylorihas a low resistance to rifabutin and has been proposed as an alternative for third-line treatment and beyond but recently has also gained attention for use as first- and second-line treatment.Areas CoveredIn this review, the authors systematically searched medical databases in order to present the current eradication rates for any treatment based on the two antibiotics, rifabutin and amoxicillin with a potent acid inhibitor. They also assessed the safety and tolerance of all the relative regimens.Expert opinionTreatment with a rifabutin- and amoxicillin-containing regimen is a valuable option when treating difficult to eradicate Helicobacter pylori infections. Its efficacy is overall 71.4%, and it is not influenced by previous antibiotics, gender, smoking habits, and age. Its results were better when used as a first- or second-line treatment. In third-line therapy and beyond, eradication rates are lower. Adverse effects of all rifabutin regimens occurred in 23% of patients and were mostly mild with bone marrow suppression being very low and reversible.

AbstractThe winter months are an important part of the year for raptors as survival throughout this period is critical for the succeeding year’s population recruitment. We reveal novel insights into the wintering of kites (Milvusspp.) on the Mediterranean island of Crete, Greece. We use a combination of 1) direct field observations, 2) online photograph searches and 3) analysis of satellite telemetry data from a tagged hybrid Red Kite × Black Kite (Milvus milvus× M. migrans migrans). The number of observations of wintering kites has increased since 1998. The wintering of numerous Black Kites with morphological features of both subspecies (M. migrans migransand M. migrans lineatus) and a hybrid Red Kite × Black Kite is a new phenomenon on Crete.

The Long-eared Owl (Asio otus) in Crete (Greece) is a common agricultural species affected by the recent changes in agro-forestry systems. Concrete studies of habitat selection are needed in order to improve our knowledge of its foraging behaviour in managed rural landscapes. In the present study, we analysed the home range size and habitat selection of 11 Long-eared Owls inside olive groves in the plain of central Crete using radio tracking data and remote sensing images. Six nominal scale and 11 landscape scale predictors were used for habitat selection analysis, using a maximum entropy approach. Home range size ranged between 337 and 969 ha while a 52% of home range overlap was observed suggesting that Long-eared Owls do not defend hunting territories. At the nominal scale, distance to potential roosts (trees) was the most important contributor to model performance, followed by vegetation heterogeneity. Furthermore, local heterogeneity of greenness was a better predictor than simply greenness at the presence location. At the landscape scale the amount of habitat openness significantly improved model performance. Incorporating landscape heterogeneity improved habitat selection prediction compared to using only discrete land cover classification. Results of our study pinpoint that although Long-eared Owls exhibit a wide range of habitat tolerance, they prefer mixed habitat conditions avoiding particularly open areas or dense olive plantations. The research has implications in the face of new reforms of European Common Agricultural policy which emphasised the importance of landscape structure in preserving biodiversity in agricultural areas of Europe.

Pelagic seabirds that breed colonially are central-place foragers; their spatial distribution is restricted to marine areas around their colonies during the chick-rearing period, when attendance and food provision to their chicks has to be intense. In this study we analyzed the foraging trips of 11 Scopoli's shearwater Calonectris diomedeabreeders that were tagged with GPS data loggers during 2014 in oligotrophic waters (Ionian Sea, western Greece), and assessed the range and oceanographic parameters of their foraging habitat. Contrary to previous findings suggesting a varying foraging strategy depending on the breeding stage, the tracked shearwaters made short trips, less than 4 days long, in the vicinity of the colony. By applying the Adaptive Kernel method, their 50% and 95% foraging range was estimated at 6871 km2and 23 014 km2respectively. In addition, generalized additive models showed that sea surface temperature (<25.5°C), minimum distance from the colony (<100 km), fishing pressure index from small scale fisheries (medium values) along with a two-dimensional soap film smoother for space (easting, northing) were the most significant factors affecting at-sea distribution of this marine top predator during the early chick-rearing period (i.e. 99.9% of the final model deviance). Our study will contribute to the revision of the boundaries of the local Special Protection Area (SPA) of Strofades. It will also address the implementation of specific conservation measures for the species at regional and national scale, and the development of a management plan for the protection of the study area.

AbstractIn the mountains of Crete, a significant number of animals are poisoned each year. The largest of the Greek islands, Crete is home to significantly large pasture and hunting areas. In an effort to address wildlife poisoning, structured interviews were conducted with specific social groups (hunters, livestock farmers, environmental officers, veterinarians) relating to wildlife poisoning in Crete to explore their intention to engage in anti-poisoning actions. The survey was conducted from early 2013 to mid-2014 and a total of 415 people were surveyed. Survey results indicate that although barriers in effective biodiversity governance have created mistrust between local environmental authorities and local residents, the main social groups related to illegal use of poisoned baits are willing to support alternative methods to address predation impacts. This paper points out the clear need for social learning strategies aimed at local interest groups and for opportunities for more meaningful and democratic environmental policy processes in order to sustain the results of biodiversity conservation plans in the long term.

Wire electrical discharge machining (WEDM) is investigated in the perspective of zero-defect manufacturing with the scope to detect anomalous process conditions leading to typical defects generated during WEDM, i.e. the occurrence of lines and marks on the resulting workpiece surface. A multiple sensor monitoring system is employed to acquire high sampling rate sensorial data relative to signals of voltage and current in the gap between workpiece and wire electrode. An advanced signal processing methodology is implemented to extract and select the most relevant features useful to identify the undesired process conditions through a cognitive pattern recognition paradigm.

Thanks to recent technology related to product monitoring and data communication, it is now possible for a company to gather various kinds of product usage data during its operation in a ubiquitous way. However, the application of the newly gathered data is still vague and immature. If the data is transformed into appropriate information or knowledge, it would be possible to improve products through design modification, maintenance enhancement, elaborate end-of-life decision and so on. This article deals with the application of product usage data to support design modification. Design modification can be achieved by finding and fixing defective design parameters and affecting factors. This done by a complex procedure which is composed of several steps including diverse data processing technique such as function structure model, degradation scenario, function performance degradation evaluation, clustering and relation matrix. The proposed method assesses the status of working product, classifies the field data (i.e. working environment/operation) according to the status and identifies suspicious field data causing the poor working status. Then, the suspicious field data is correlated with design parameters; thus highly defective design parameters can be identified. For the product improvement, the defective design parameters should be reviewed and modified with a high priority. The proposed method is validated by a case study on a locomotive braking system. This work shows the possibility to transform product usage data into information for product improvement, which can serve as a guideline for product usage data application for other product improvement through product usage data.

Consideration for the energy consumption and environmental impacts is required depending on the changed capacity under a flexible and reconfigurable manufacturing environment. This article focuses on a holistic production planning approach in a reconfigurable manufacturing system. The energy consumption and material flows that are incurred on the reconfigurable manufacturing system are defined from the perspective of the processing plan describing how to make a part. The suggested energy estimation model integrates the existing literature and set up a newly modified model including diverse part handling systems such as automated guided vehicle and conveyor in more detail. Alternative system reconfigurations are analysed in order to dynamically evaluate the performance in terms of different holistic criteria such as the energy consumption, environmental effects and throughput. A production planning model with the multi-objective function for minimising the energy consumption and maximising the throughput is developed. The benefit coming from the adoption of suggested model has been addressed with reference to a real industrial use case study.

The aim of the study was to determine which of three two-parameter fitting functions (exponential, linear-log, and negative-power function of time) most accurately models early chromium-51-EDTA (51Cr-EDTA) plasma concentration data prior to 120 min in patients with cirrhosis and ascites and understand how these fitting functions affect the calculation of the area under the plasma concentration curve (AUC).

In the framework of zero-defect manufacturing, an advanced sensor monitoring procedure aimed at detecting the process conditions leading to surface defects in Wire Electrical Discharge Machining (WEDM) is proposed. WEDM experimental tests were carried out with the employment of a multiple sensor monitoring system to acquire voltage and current signals in the gap between workpiece and wire electrode at the high sampling rate of 100MHz. In order to extract from the acquired signals the most relevant features that can be useful in the identification of abnormal process conditions, an advanced sensor signal processing methodology based on signal feature extraction for the construction of sensor fusion pattern vectors is proposed and implemented.

The exact formulation and solution for the static flexural response of a rigid perfectlyplastic freely floating plate subjected to lateral axisymmetric loading is presented. The square yield condition is adopted with the associated flow rule. The plate response is divided into three phases. Initially, the plate moves downwards into the foundation as a rigid body phase I. Subsequently, the plate deforms in a conical mode in addition to the rigid body motion phase II. At a certain value of the load a hingecircle forms which may move as the pressure increases further phase III. The nature of the solution during the third phase depends upon the parameter α=a/Rratio of radius of loaded area to the plate radius. When α=αs≃0.43505the hingecircle remains stationary under increasing load. For α<αsthe hingecircle shrinks, whereas for α>αsthe hingecircle expands with increasing pressure. The application of the present results to the problem of laterally loaded floating ice plates is examined.

The aim of this study was to identify a practical sampling regimen and calculation method that could be used to measure the glomerular filtration rate in patients with ascites using plasma sampling.

To compare the efficacy, compliance, and tolerability of a quadruple, nonbismuth-containing concomitant therapy with standard triple therapy, both of the duration of 10 days, for Helicobacter pylorieradication.

We consider a three-stage dynamic flexible flow shop scheduling problem in which jobs of multiple types arrive dynamically over time, a quality feedback mechanism is present, and the setup timing and the process defect rate are closely related. At each machine in the second stage, a sequence-independent setup operation is necessary to changeover job types. Once a setup is done for a job type at a machine, the defect rate for the job type at the machine is reset to a low and stable phase which will be maintained for a predetermined time periods. However, after the phase, it turns to a relatively high and unstable phase. At the final inspection stage, jobs are inspected and the quality feedback will be given to the previous stage when the accumulative defect rate of each job type exceeds a certain tolerance level. To cope with the dynamic nature of the flexible flow shop scheduling problem, we propose two dispatching rule-based scheduling algorithms which consider the quality feedback as well as the real time shop information for the objectives of maximizing the quality rate and the mean tardiness of the finished jobs. The results of a series of simulation experiments will be given to evaluate the performance of the suggested algorithms. Since there have been few research on the shop floor scheduling problems with quality feedback, we expect that this research will make a contribution to the development of a practical real time scheduling methodology in multi-stage production systems with the consideration of the imperfect process quality.

This study introduces an overall framework for radio frequency identification (RFID) applications in product lifecycle management (PLM). Recently, with emerging technologies related to product identification and wireless mobile tele-communication, PLM provides a new environment that enables lifecycle actors to gather and analyse product lifecycle information, and make efficient decisions without spatial and temporal constraints. However, previous research has paid little attention to how to apply the emerging technologies into PLM. To cope with this limitation, in the current study, RFID applications in PLM are dealt with from technical and business viewpoints. To this end, an overall framework for RFID applications in PLM is proposed. It contains the definition of a product embedded information device (PEID) that uses RFID technology, its specification and operation scenarios for each application. Furthermore, application issues and their overall procedures are introduced for each lifecycle phase.

We studied the foraging behaviour of Eurasian griffons Gyps fulvuson the island of Crete during 1997–2005 by direct observations in four colonies and by monitoring the movements of seven radio-equipped individuals. The estimated foraging range of griffon colonies, based on direct observations, ranged from 206–851 km2by using the Minimum Convex Polygon method, and 195–527 km2by using the Adaptive Kernel method, with corresponding means of 472 and 380 km2, respectively. Meanwhile, radio-tracking showed that foraging vultures covered an area ranging from 390–1300 km2. The mean foraging radius was calculated at ca 15 km and the mean maximum one at 29.9 km. On windless days, griffons' mean cross-country speed was 5.1 m/second (maximum = 13.3 m/second), with a mean climbing rate of 0.6 m/second and a mean inter-thermal gliding speed of 18.8 m/second. Any livestock carrion located up to 9 km from a colony was exploited by its members with minimum competition from individuals of adjacent areas. In total, we recorded 23 feeding incidences which took place at a mean distance of 8.4 km from the colonies. The food types identified were sheep carcasses located near stock-farms and offal disposed in waste dumps in the vicinity of the colonies. On average, the griffons allocated 7.6 hour/day to food searching. This varied significantly between months and seasons. The shortest foraging time was recorded in December (6.4 hour/day) and the longest in June (9.3 hour/day). A significant difference of one hour after sunrise was detected in the departure time from the colony between seasons revealing that griffons departed earlier during winter trying to maintain their foraging budget within the available daytime limits.

In this study, we propose a new method to analyse newly gathered data for product design improvement. The proposed method provides the transformation from usage data gathered in the middle-of-life (MOL) phase to information for design improvement in the beginning-of-life (BOL) phase. To this end, we first define function performance, function performance degradation and the behaviour of function performance degradation changed during MOL. The proposed definitions help product design engineers to understand components/parts' working status during the usage period of a product. Based on the evaluation of components/parts' working status, critical components/parts can be discriminated. For the found critical components/ parts, their working status are examined and correlated with field data which consist of operational and environmental data. The correlation provides the engineers with critical field data which have main effects on the worse working status of products. To verify our method, we have carried out a locomotive case study.

The effects of transjugular intrahepatic portocaval shunt (TIPS) on the survival of grafts and patients after liver transplantation (LTx) have only been documented in small series and with only a comparative description with non-TIPS recipients. We evaluated 61 TIPS patients who had a subsequent LTx and compared these with 591 patients transplanted with cirrhosis without TIPS. Pretransplant characteristics were similar between groups. Graft survival at 1, 3 and 5 years post-LTx was 85.2, 77 and 72.1 (TIPS) and 75.3, 69.8 and 66.1 (controls). Patient survival at the same points was 91.7, 85 and 81.7, respectively (TIPS) and 85.4, 80.3 and 76.2 (controls). Cox regression showed the absence of TIPS pre-LTx, transfusion of >5 units of blood during LTx, intensive care unit (ICU) stay post-LTx >3 days and earlier period of transplant to be significantly associated with a worse patient and graft survival at 1 year. Migration of the TIPS stent occurred in 28 of cases, increasing the time on bypass during LTx, but was not related to graft or patient survival. TIPS may improve portal supply to the graft and reduce collateral flow, improving function. This may account for the improved adjusted graft and patient survival by Cox regression at 12 months. Long-term survival was not affected.

The effects of transjugular intrahepatic portocaval shunt (TIPS) on the survival of grafts and patients after liver transplantation (LTx) have only been documented in small series and with only a comparative description with non-TIPS recipients. We evaluated 61 TIPS patients who had a subsequent LTx and compared these with 591 patients transplanted with cirrhosis without TIPS. Pretransplant characteristics were similar between groups. Graft survival at 1, 3 and 5 years post-LTx was 85.2%, 77% and 72.1% (TIPS) and 75.3%, 69.8% and 66.1% (controls). Patient survival at the same points was 91.7%, 85% and 81.7%, respectively (TIPS) and 85.4%, 80.3% and 76.2% (controls). Cox regression showed the absence of TIPS pre-LTx, transfusion of >5 units of blood during LTx, intensive care unit (ICU) stay post-LTx >3 days and earlier period of transplant to be significantly associated with a worse patient and graft survival at 1 year. Migration of the TIPS stent occurred in 28% of cases, increasing the time on bypass during LTx, but was not related to graft or patient survival. TIPS may improve portal supply to the graft and reduce collateral flow, improving function. This may account for the improved adjusted graft and patient survival by Cox regression at 12 months. Long-term survival was not affected.

Non alcoholic fatty liver disease (NAFLD) is often part of the metabolic syndrome which includes central obesity, dyslipidaemia, insulin resistance/type 2 diabetes mellitus and hypertension. In turn, NAFLD may be associated with an increased vascular risk. Several experimental models which express histological steatosis or steatohepatitis with fibrosis have been described. This review identifies those models of NAFLD with features of vascular risk.

With more than 80% of the species global population breeding in Greece, Eleonora’s Falcon (Falco eleonorae) is reported to be the most important bird species in the country. A national population survey was conducted during the breeding seasons 2004–2006 in order to assess the species' breeding distribution and population size. This census was the first of its kind and was part of a global population survey, involving more than 80 field workers. Standard field protocols, described in the International Species Action Plan, and a GIS interactive database were developed. Data were stored and spatially explored in conjunction to historical information and past records. A total of about 17,660 falcons were counted or an estimated 12,300 breeding pairs, which were concentrated in six major regions, i.e., northeast Aegean, Sporades, east Cyclades, Antikythira, southwest Dodecanese and the satellite islets of eastern Crete. Compared to previous descriptions of breeding colonies and population status, spatial variation in site occupancy was detected with a population decline in one of the aforementioned regions and an apparent increase in all the rest. The results of this national survey, expected to be repeated every 10 years, provided guidance for reviewing the conservation status of Eleonora’s Falcon in Greece and baseline information for future monitoring of its population.

The closed-loop product life cycle management (closed-loop PLM) system focuses on tracking and managing the information of whole product life cycle, with possible feedback of information to product life cycle phases. It provides opportunities to reduce the inefficiency of life cycle operations and gain competitiveness. Thanks to the advent of hardware and software related to product identification technologies, e.g. radio frequency identification (RFID) technology, recently the closed-loop PLM has been highlighted as a tool of companies to enhance the performance of their business models. However, implementing the PLM system requires a high level of coordination and integration. To this end, it is prerequisite to investigate what are the main components for closed-loop PLM and how they are related to each other. To address this need, the curent study focuses on the system architecture of closed-loop PLM with respect to business model, hardware, and software.

Acute alcoholic hepatitis (AAH) is a frequent inflammatory liver disease with high short-term mortality rate. In this review, relationships between alcohol abuse and the epidemiology and the outcomes of AAH are discussed, as well as AAH pathogenesis. The role of endotoxins, tumor necrosis factor α, fibroblasts, and immune response to altered hepatocyte proteins is discussed. The need of a careful prognosis, supported by the use of Maddrey score, by the model for end-stage liver disease Mayo end-stage liver disease (MELD) score or by the Glasgow alcoholic hepatitis score, is outlined, as the use of the most effective drugs (glucocorticoids and anti-tumor necrosis factor α infliximab) is recommended only in severe AAH cases. The problems of liver transplant in severe AAH, and the need of a 6-month alcohol abstinence before transplant, are discussed, as well as the need of a careful psychologic assessment before the transplant.

The STEP effort and the STEP-NC project have produced a great deal of work on features for mechanical parts and how to manufacture parts based on these. However, there is at present less information about how to manufacture aesthetic products with less well-defined features. The aim of the present paper is to describe an approach to communication and machining features in stone products. The work was done as part of a project, LITHO-PRO, which had the main aim of developing machining for dry high-speed milling of stone and industrial ceramics. As part of this project the EPFL worked on CAD and CAM functions for aesthetic products. Since the main aim of the project was to develop a new machine and machining process, it was decided that the STEP-NC philosophy was appropriate for communication. However, the stone products are usually aesthetic rather than functional so the feature set defined in the STEP AP-224 document could not be used directly. The aim of the paper is to present an approach to feature definition in terms of manufacturing strategies which is an extension to the classical, mechanical engineering features already determined as part of STEP.

The current paper describes the implementation of the wire electro discharge machining (EDM) algorithms for the STEP-NC project and some possible extensions. Wire EDM uses many working parameters (parameters for spark generation, speed of penetration, etc.) the setting of which needs expert system methods. These expert systems are a coded form of the company knowledge and are based on their experience. The higher information level provided by STEP-NC allows the development of new algorithms to drive the wire. The current way of programming the wire motion is to consider it as a milling tool for 2.5 axis machining operations: the wire trajectory is computed using 2D planar curve offsetting and collision detection algorithms. The use of explicit ruled surfaces allows real 3D offsetting and collision detection.The paper starts by describing the data model and architecture of the demonstration system which was developed during the project. This can be thought of as a simplified process planning phase. The second part of the paper describes algorithms that have been implemented in the STEP-NC environment for prototype software running on the wire EDM NC controller. The final part describes some open questions that remain at the end of the project.

This paper presents a singularity analysis for a 3-DOF parallel manipulator with R-P-S (Revolute-Prismatic-Spherical) joint structure. All three types of singularities are investigated with most attention paid for direct kinematics singularities (DKS). The loci of inverse kinematics and combined singularities are identified using a new approach. The equation of DKS is defined first from the condition of existence of an instantaneous motion. The geometrical method is used to find the loci of trajectories corresponding to DKS-s. As a result of these investigations, an optimization procedure was proposed of a robot design in order to have an enlarged singularity free part of the working space. The construction of a singularity free path is discussed without changing the robot trajectory by selecting the appropriate inverse kinematics task solution.

Griffon vulture (Gyps fulvus) population surveys were conducted during 1996–2002 in the island of Crete (Greece) to document population status and structure. Fieldwork was carried out during the breeding period when birds could be monitored in their colonies. Total population size was estimated at 379 individuals (range = 341–417) with adult birds comprising 63%. The breeding population was estimated at 141 pairs, which were distributed on an average in 23 colonies per year (range = 16–30) while the mean number of breeding pairs that laid eggs was 98 (range= 64–126). Crete thus supports the largest insular population of the species in the world and hosts 70–80% of the breeding population of the species in Greece. Population density was estimated at 6.9 individuals/100 km2, 2.6 breeding pairs/100 km2and 1.8 nesting pairs/100 km2. The average home range of an occupied colony (i.e., breeding group) was estimated at ca. 204 km2producing a theoretical foraging range of 8 km radius around the breeding cliff. No trends in the total number of individuals and breeding pairs appeared to exist, although significant differences in population size of individual colonies occurred between the years. The majority of the population was concentrated in small-sized colonies, which showed a low occupancy rate. The number of abandoned sites and the colonization of new ones could represent a shift of breeding pairs to alternative colonies provoked by local food abundance and conspesific attraction.

A new solution of the inverse kinematics task for a 3-DOF parallel manipulator with a R-P-S joint structure is obtained for a given position of end-effector in the form of simple position equations. Based on this the number of the inverse kinematics task solutions was investigated, in general, equal to four. We identify the size of the manipulator feasible area and simple relationships are found between the position and orientation of the platform. We prove a new theorem stating that, while the end-effector traces a circular horizontal path with its centre at the vertical z-axis, the norm of the joint coordinates vector remains constant.

A general fuzzy multicriteria decision aid method for conceptual design is proposed. It is used for selecting the best compromise alternative, among a finite set of design concepts, considering environmental and economic performance. At the conceptual design phase most of the environmental impact is committed, whereas at that stage the design concepts are imprecisely defined and should be selected based on multiple, often conflicting criteria. Three vacuum cleaners, using different design principles for the dust storage, are analyzed. The best compromise design alternative is selected, considering trade offs between end-of-life profit and environmental criteria.

Generating the medial surface for a general boundary representation model raises several difficulties. Problems might emerge from the complexity of the resulting equations, singularities caused by unforeseen relative boundary element positions and orientations, etc. The majority of the current algorithms are based on the topology of the boundary representation model and produce wireframes composed of straight lines regardless of the real medial surfaces. Many of the solids used in engineering can be represented by extrusions, delimited by a cross-section and an extrusion distance. This paper develops a fast and efficient method for creating the facetted approximations of the medial surfaces of extrusions generated by sweeping along the normal direction to the generating cross-section.

This paper presents a new data model for wire-EDM technology. It was developed for data exchange between CAD-CAM-CNC machines. This data model will become part of the ISO-14649(Data model for Computerized Numerical Controllers) international standard. The overall structure and the design goals of this new STEP based data model is presented.

We consider the problem of determining the disassembly schedules of used products while satisfying the demand of their parts/components over a planning horizon. The case of multiple product types with parts commonality is considered for the objective of minimizing the sum of setup, disassembly operation, and inventory holding costs. A heuristic algorithm is proposed using the linear programming relaxation approach. Test results of the case study on the data obtained from a disassembly shop show that the heuristic algorithm suggested in this paper works well for practical problems.

There exist several scenarios for treating an end of life (EOL) product and each scenario has different environmental, social and economic consequences. An EOL scenario can be better than another with respect to one criterion but worse with respect to another criterion. To compare EOL scenarios with respect to conflicting criteria, a multiple criteria decision aid (MCDA) method should be used. In this paper, we present the MCDA approach developed in the project AEOLOS (An End-of-Life of Product Systems) for supporting users in the selection of the best scenario for treating an EOL product on the basis of their preferences and the performances of the EOL scenarios with respect to relevant criteria.

We propose in this paper a model for an elementary activity of the computer aided design (CAD) process, taking into account the specificity of the utilization of a computer: its capability to manipulate a relatively high volume of data and to explore alternatives quickly and systematically. The CAD activity is defined according to a given expertise domain (functionality, assembly, manufacturing, etc.) which is examined with respect to two inter-related subtasks: knowledge processing and data processing. Knowledge processing manipulates the knowledge model which represents an expert's point of view on the domain. Four things determine the knowledge model: a typology of combinable elements, a typology of possible relations between elements, an expert rule base for the creation of problem models (translation of problem data in elements and relations), and a set of criteria to evaluate the quality of solutions. Data processing manipulates the computational model which represents the computing point of view of the domain. We use the constraint satisfaction problem (CSP) model as the computational model. The relationship between subtasks is done according to the manner in which the knowledge model is translated in to the computational model.The proposed model of the CAD process allows an adaptive man-machine task sharing by allocating the user interaction to the knowledge model while the computer interacts with the computational model. An example from the assembly planning domain illustrates the model.Once the different CAD activities are determined, they can be combined to form a CAD process. The activities are coordinated by exchanging partial solutions (which can be done during knowledge processing and/or data processing), rules and evaluation criteria (during knowledge processing). Such kinds of CAD processes can also be used to define recursively the CAD activity of higher levels of abstraction.

Pseudobrookite-type MgTi2O5(karrooite) is a synthetic crystalline phase with the Bbmm structure and a component in orthorhombic oxide solid solutions, R2+Ti2O5-R3+2TiO5, which are present as accessory minerals in lunar and terrestrial rocks. In this study, we present a model for the molar Gibbs free energy of MgTi2O5as a function of T, P, and the order parameter s = XM1Mg- 2XM2Mg, (-1 ≤ s ≤ 1). We describe the molar Gibbs free energy, (G̅), with the equation: G̅ = g̅0+ g̅1·(1 - s) + 3/2g̅2·(1 - s2) - T·S̅config, and take parameter go to represent the molar Gibbs free energy of ordered MgTi2O5(s = 1), whereas parameters g1and g2may represent cation-disorder contributions. We used powder and single-crystal X-ray diffraction, and high-temperature relative enthalpy data, to calibrate the disorder contribution to the volume (bo= 7.3822·10-3J/bar), and the model parameters g1(7370.8 J/mol) and g2(3576.1 J/mol), and heat capacity and volume equation coefficients. We also optimized standard state thermodynamic data from the elements for ordered MgTi2O5, (ΔH0= - 2 498 515.28 J/mol, S0= 149.55 J/(mol·K), ΔG0= -2 362 181.72 J/mol, V0= 5.445 J/bar) consistent with the model parameters and equations, the thermodynamic data in QUILF, and phase-equilibrium experiments involving MgTi2O5, geikelite, rutile, orthoenstatite, and forsterite in the range 973 to 1673 K and 0.0001 to 2.0 GPa. Finally, we investigate theoretically the stability of MgTi2O5(karrooite) with respect to geikelite, rutile, diopside, enstatite, and forsterite in the CaO-MgO-TiO2-SiO2system. We find that diopside- and titanite-bearing reactions require extremely high temperatures, and are thus not stable with respect to liquid. The inferred phase relations can be of help in understanding the stability of MgTi2O5with respect to rutile, geikelite, forsterite, and orthoenstatite, and by extrapolation that of armalcolite relative to rutile, ilmenite, olivine, and orthopyroxene in terrestrial mantle rocks and high-Ti lunar basalts.

Pseudobrookite-type MgTi2O5(karrooite) is a synthetic crystalline phase with the Bbmm structure and a component in orthorhombic oxide solid solutions, R2+Ti2O5-R3+2TiO5, which are present as accessory minerals in lunar and terrestrial rocks. In this study, we present a model for the molar Gibbs free energy of MgTi2O5as a function of T, P, and the order parameter s = XM1Mg- 2XM2Mg, (-1 ≤ s ≤ 1). We describe the molar Gibbs free energy, (G̅), with the equation: G̅ = g̅0+ g̅1·(1 - s) + 3/2g̅2·(1 - s2) - T·S̅config, and take parameter go to represent the molar Gibbs free energy of ordered MgTi2O5(s = 1), whereas parameters g1and g2may represent cation-disorder contributions. We used powder and single-crystal X-ray diffraction, and high-temperature relative enthalpy data, to calibrate the disorder contribution to the volume (bo= 7.3822·10-3J/bar), and the model parameters g1(7370.8 J/mol) and g2(3576.1 J/mol), and heat capacity and volume equation coefficients. We also optimized standard state thermodynamic data from the elements for ordered MgTi2O5, (ΔH0= - 2 498 515.28 J/mol, S0= 149.55 J/(mol·K), ΔG0= -2 362 181.72 J/mol, V0= 5.445 J/bar) consistent with the model parameters and equations, the thermodynamic data in QUILF, and phase-equilibrium experiments involving MgTi2O5, geikelite, rutile, orthoenstatite, and forsterite in the range 973 to 1673 K and 0.0001 to 2.0 GPa. Finally, we investigate theoretically the stability of MgTi2O5(karrooite) with respect to geikelite, rutile, diopside, enstatite, and forsterite in the CaO-MgO-TiO2-SiO2system. We find that diopside- and titanite-bearing reactions require extremely high temperatures, and are thus not stable with respect to liquid. The inferred phase relations can be of help in understanding the stability of MgTi2O5with respect to rutile, geikelite, forsterite, and orthoenstatite, and by extrapolation that of armalcolite relative to rutile, ilmenite, olivine, and orthopyroxene in terrestrial mantle rocks and high-Ti lunar basalts.

Disassembly scheduling is the problem of determining the ordering and disassembly schedule for used products while satisfying the demands of their individual parts or components over the planning horizon. The objective is to minimize the sum of purchase, inventory holding, and disassembly operation costs, subject to capacity restrictions in each period. In this paper, an integer programming model, which is a reversed form of the multi-level capacitated lot sizing problem, is suggested to represent and solve the problem optimally. A case study on used inkjet printers is worked out and the test results are reported.

High pressure, high temperature phase equilibria experiments were performed to investigate the effect of TiO2on mineral-liquid equilibria for near natural olivine + orthopyroxene-saturated mafic liquids. At 1.2 GPa and 1360°C, and at 2.8 GPa and 1530°C, near-natural picritic basaltic liquids with TiO2concentrations ranging from 0.4 to 22 wt.% were forced to be in equilibrium with olivine (ol) + orthopyroxene (opx) by adding appropriate quantities of San Carlos olivine with increasing TiO2. Titanium enrichment of the ol + opx saturated mafic liquids results in nearly pressure-independent linear decreases in SiO2amounting to 0.60 ± 0.04 and 0.56 ± 0.05 wt.% SiO2per wt.% TiO2at 1.2 and 2.8 GPa, respectively. Olivine-liquid Fe-Mg KDdecreases at 1.2 GPa from 0.33 at 0.4 wt.% TiO2down to 0.22 at 19 wt.% TiO2. A similar trend, shifted to slightly higher KDvalues, is observed at 2.8 GPa.

Abstract:  The heat capacity of end-member titanite and (CaTiSiO5) glass has been measured in the range 328–938 K using differential scanning calorimetry. The data show a weak λ-shaped anomaly at 483 ± 5 K, presumably associated with the well-known low-pressure P21/a ⇆ A2/a transition, in good agreement with previous studies. A value of 0.196 ± 0.007 kJ mol−1 for the enthalpy of the P21/a ⇆ A2/a transition was determined by integration of the area under the curve for a temperature interval of 438–528 K, bracketing the anomaly. The heat capacity data for end-member titanite and (CaTiSiO5) glass can be reproduced within <1% using the derived empirical equations (temperature in K, pressure in bars):

Critical evaluation of the thermodynamic data for titanite, in conjunction with a heat capacity equation that takes into account the P21/a ↔A2/a transition and a more complete P-V-T data set for titanite, indicates that: (1) enthalpy of formation values greater than -2600 kJ/mol are not supported by calorimetry; (2) calculated internally consistent feasible solutions converge to enthalpy of formation from the elements values between -2608 and -2600 kJ/mol and 113 to 121 J/mol⋅K for the entropy; (3) the practice of adjusting the enthalpy of formation to fit phase equilibrium experiments may be erroneous, in contrast, it is the currently accepted entropy of 129.20 ± 0.84 J/mol⋅K that may need revision to a smaller value. Consequently, we optimize standard-state properties for end-member titanite (P21/a structure) consistent with the thermodynamic data in the program QUILF. In addition, we use a modified version of the program to calibrate equilibria among titanite (CaTiOSiO4), Fe-Mg-Ti ilmenite and spinel, Ca-Mg-Fe pyroxenes and olivine, and quartz. Calculations at 1 and 3 kbar, and 650, 850, and 1100 °C, in the system CaO-MgO-FeO-Fe2O3-TiO2-SiO2, suggest that the reactions:

In the system CaO-MgO-FeO-Fe2O3-TiO2--SiO2, equilibria among titanite, pyroxene(s), olivine, spinel phase, ilmenite, and quartz constrain fO₂, T, aSiO₂, aTiO₂, aFe, and the compositional variables, μTiFe2+Fe3+-2, μCa(Mg,Fe)-1, and consequently μMg,Fe-1among the silicate and oxide phases. These equilibria can provide the framework for a better understanding of relevant titanite-bearing natural assemblages. In addition, such equilibria can constrain the variables that operate during crystallization of igneous and metamorphic rocks. Titanite-bearing assemblages with pyroxene(s), Fe-Mg-Ti ilmenite and spinel, olivine, and quartz are rare in metamorphic rocks but are common in igneous rocks where they are more commonly reported in plutonic than in volcanic rocks. Probably because, at high temperatures, titanite cannot coexist with the relative common in volcanic rocks sub-assemblage augite + orthopyroxene + olivine + spinel phase + ilmenite. Moreover, decreasing pressure and temperature conditions appear to favor titanite. Thus, it is not surprising that titanite is commonly observed in slowly cooled rocks, albeit, most typically in association with amphibole. We argue that the titanite + amphibole association is favored by high aH₂Oand, because aH₂Otypically increases during crystallization of a pluton, titanite + amphibole (and consequently titanite) is more common in plutonic than in volcanic rocks.

In the system CaO-MgO-FeO-Fe2O3-TiO2--SiO2, equilibria among titanite, pyroxene(s), olivine, spinel phase, ilmenite, and quartz constrain fO₂, T, aSiO₂, aTiO₂, aFe, and the compositional variables, μTiFe2+Fe3+-2, μCa(Mg,Fe)-1, and consequently μMg,Fe-1among the silicate and oxide phases. These equilibria can provide the framework for a better understanding of relevant titanite-bearing natural assemblages. In addition, such equilibria can constrain the variables that operate during crystallization of igneous and metamorphic rocks. Titanite-bearing assemblages with pyroxene(s), Fe-Mg-Ti ilmenite and spinel, olivine, and quartz are rare in metamorphic rocks but are common in igneous rocks where they are more commonly reported in plutonic than in volcanic rocks. Probably because, at high temperatures, titanite cannot coexist with the relative common in volcanic rocks sub-assemblage augite + orthopyroxene + olivine + spinel phase + ilmenite. Moreover, decreasing pressure and temperature conditions appear to favor titanite. Thus, it is not surprising that titanite is commonly observed in slowly cooled rocks, albeit, most typically in association with amphibole. We argue that the titanite + amphibole association is favored by high aH₂Oand, because aH₂Otypically increases during crystallization of a pluton, titanite + amphibole (and consequently titanite) is more common in plutonic than in volcanic rocks.

Critical evaluation of the thermodynamic data for titanite, in conjunction with a heat capacity equation that takes into account the P21/a ↔A2/a transition and a more complete P-V-T data set for titanite, indicates that: (1) enthalpy of formation values greater than -2600 kJ/mol are not supported by calorimetry; (2) calculated internally consistent feasible solutions converge to enthalpy of formation from the elements values between -2608 and -2600 kJ/mol and 113 to 121 J/mol⋅K for the entropy; (3) the practice of adjusting the enthalpy of formation to fit phase equilibrium experiments may be erroneous, in contrast, it is the currently accepted entropy of 129.20 ± 0.84 J/mol⋅K that may need revision to a smaller value. Consequently, we optimize standard-state properties for end-member titanite (P21/a structure) consistent with the thermodynamic data in the program QUILF. In addition, we use a modified version of the program to calibrate equilibria among titanite (CaTiOSiO4), Fe-Mg-Ti ilmenite and spinel, Ca-Mg-Fe pyroxenes and olivine, and quartz. Calculations at 1 and 3 kbar, and 650, 850, and 1100 °C, in the system CaO-MgO-FeO-Fe2O3-TiO2-SiO2, suggest that the reactions:

This paper focuses on the disassembly sequencing, which is the problem of determining the disassembly level and the corresponding disassembly sequence for a product at its end-of-life with the objective of maximizing the overall profit. Parallel disassembly and sequence-dependent operation times are considered by developing an extended process graph obtained from a transformation of a conventional AND/OR graph. Then, an integer programming formulation is developed with precedence constraints that allows its resolution with standard techniques. Finally, an optimal solution is obtained, with a reasonable amount of computation time, for an industrial application of a subassembly of a copy machine.

The problem under consideration is the cost estimation and consequent bid preparation for machined parts subcontracted to mechanical SMEs. The system is based (i) on a manufacturing feature based product description of the part to be machined and (ii) on a non-linear model of its process plan using Petri nets, taking into consideration processing alternatives and precedence constraints. In this paper, a particular matrix implementation of our Petri net representation is described and demonstrated. Minimum time or cost process plans are obtained through simulation of the firing of the Petri net model, in its matrix form, with machining heuristics.

In this paper a new Petri net class (Chameleon systems) for modeling and analyzing joined process planning and job shop production planning is proposed based on the multi-level Petri net model introduced by Valk (1995). Chameleon system is a High-level Petri net extended with time that consists of a High-level Petri net modeling the workshop which is called system net and ordinary Petri net modeling the jobs and setups which act as tokens of the system net and therefore are called token nets. Process plans of the jobs are partial orders of operation groups and alternatives. The uncertainty of operation duration is captured by a new time model. The advantages of this new modeling approach are the following: (i) a modular construction of the joined process and job shop planning is allowed, (ii) classical known Petri net analysis methods can be applied and (iii) the analysis can be done at different levels of abstraction.