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This thesis deals with multibody dynamic simulation of mechanical systems in the product development process. The approach is to make the process of multibody dynamics simulation more efficient by structuring of the simulation, simulation models and their usage. Previous work has concentrated on developing faster calculation methods and more specialised simulation software. Efforts have been made to clarify how computer tools and multibody dynamic analysis methods are used in product development in industry today. Insight into the knowledge domains of product development and multibody dynamics is given together with an introduction to the area of distributed simulation, modularisation techniques and nonlinear analysis. The mentioned domains have traditionally been separated but the introduction of concurrent engineering and faster computers puts new demands on the need for integration of computer support and analysis in the development process. The performed work is to be seen as cross-functional work in order to bring different domains together for the sake of a better total product development. The applications areas used in the work are all within vehicle system dynamics. A proposal for performing the multibody dynamics methodology in a distributed and modular way in the product development process is given based on the performed work together with a prototype implementation.

Purpose – The purpose of this thesis is to present the result of simulation process maturity (SPM) assessments in the pharmaceutical and manufacturing industry using a process maturity model derived from empirical research. The model is used to benchmark an organisations simulation capability and to apply the results of the assessment to develop a road map for implementing simulation process improvement as well as integration initiatives within the organisation. Methodology approach – This is a survey-based research on benchmarking simulation process in the industry. The SPM model was adopted as the reference model and data were collected through interviews with key simulation staff within each organisation with the aim of identifying anomalies or conformities in the way simulation projects are performed. A pragmatic scoring system was introduced based on the fulfilment of defined requirements to score findings from the interviews based on defined SPM tenets and the sample profiles SPM tier calculated. Findings – Each tenet of the SPM model consists of 3 maturity tiers with increasing level of complexity of the process. The results of the assessment showed that the overall average of SPM of the sample profile is at tier 2. Key discrepancies representing the lowest and highest ratings are found to be mostly related to process understanding and management commitment.  A higher mean score is recognised for the samples displaying a deeper integration with top management and alignment with organisational strategic objectives. These maturity tiers and tenets reflect the extent of the implementation of contracting best practices within the studied industries. Research limitations/implications – This thesis uses a purposeful sampling approach designed at acquiring data on an organisational current simulation process. The assessment survey was conducted solely on qualified simulation personal within pharmaceutical and manufacturing. It is as such not clear whether the proposed SPM model will work within other types of industrial settings and if so how to organise the simulation activities in that setting. By purposively selecting the sample profile there are limitations concerning generalizability. Still, the conclusion based on the analysis of these benchmarking assessments may offer key take-aways in the context of process management. Practical implications – The findings suggest that benchmarking can be effective in measuring and improving simulation process capabilities within the pharmaceutical and manufacturing industry. The use of these benchmarking assessment can be instrumental in tracking the achievements of this process and enable management to measure the quality of the simulation activities in addition to offer guidance on what development actions to prioritise. By improving the simulation process, organisations will work towards furthering the integrity and credibility of its simulation studies. Originality/value – The existing literature does properly not present adequate empirical research in the field on maturity on the simulation process.  Also, the analysis method used in this study will further help organisation to perform self-assessment and determine their respective SPM. This value is reflected in using the results for implementing simulation process improvement initiatives that will ensure that the process is conducted in the most effective and efficient way.

The diploma thesis deals with using discrete event simulation as a tool for supporting decision-making process in the company with usage of simulation software Plant Simulation. This work briefly introduces business process modeling and simulation problems. In the diploma thesis there two varieties two varieties of supplying parts, compared with each other in a process view and there is a particular proposal solution, including the economical evaluation.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Systems Science and Industrial Engineering, 2009. / Includes bibliographical references.

Manage your simulation processes, data, tools and workflows The pressure to shorten time-to-market while improving product performance and quality is driving the increased use of simulation throughout the product lifecycle. However, without some form of simulation data management, simulation itself can become a process bottleneck. The Teamcenter simulation process management solution has been specifically designed to help you get control of your simulation data and processes in the context of an overall product lifecycle management (PLM) system. With Teamcenter, you can avoid common problems such as analyses being performed on obsolete data, poor visibility to simulation results, and results arriving too late to influence design direction. You can efficiently manage and share complex product simulations so they are available to all product decision-makers across your business.

Information security is of utmost concern in a multiuser environment. The importance of security is felt much more with the widespread use of distributed database. Information is by itself a critical resource of an enterprise and thus the successful operation of an enterprise demands that data be made accessible only by authorized users and that the data be made to reflect the state of the enterprise. Since many databases are online, accessed by multiple users concurrently, special mechanisms are needed to insure integrity and security of relevant information, This thesis describes a model for computer database security that supports a wide variety of security policies. The terms security policies and security mechanism are presented in Chapter I. The interrelated topics of security and integrity are discussed in some detail. The importance and means of insuring security of information is also presented in this chapter. In Chapter 2, the work done In the field of Computer Security and related topic has been presented. In general computer security models could be classified broadly under the two categories. (1) Models based on Access Control Matrix and (2) Models based on Information Flow Control. The development of the models baaed on the above two schemes as also the policies supported by some of the schemes are presented in this chapter. A brief description of the work carried out in database security as aim the definition of related terns are given in Chapter 3. The interrelationship between the operating system security and database security is also presented in this chapter. In general the database security mechanism depends on the existing operating system. The database security mechanism are thus only as strong as the underlying operating system on which it is developed. The various schemes used for implementing database security such as access controller and capability lists are described in this chapter. In Chapter 4, a model for database security has been described. The model provides for: (a) Delegation of access rights by a user and (b) Revocation of access rights previously granted by a user. In addition, algorithms for enforcing context dependent and content dependent rules are provided in this cheer. The context-dependent rules are stored in the form of elements of a bit matrix. Context-dependent rules could then be enforced by suitably manipulating the bit matrix and interpreting the value of me elements of the matrix, The major advantage of representing the rules using bit matrices is that the matrix itself could be maintalnet3 in main memory. The time taken to examine if a user is authorized to access an object is drastically reduced because of the reduced time required to inspect main memory. The method presented in this chapter, in addition to reducing the time requirement for enforcing security also presents a method for enforcing decentralized authorization control, a facility that is useful in a distributed database environment. Chapter 5 describes a simulation method that is useful for comparing the various security schemes. The tasks involved in the simulation are – 1. Creation of an arrival (job). 2. Placing the incoming job either in the wait queue or in the run state depending on the type of access needed for: the object. 3. Checking that the user on whose behalf the job is being executed is authorized to access the object in the mode requested. 4. Checking for the successful completion of the job and termination of the job. 5. Collection of important parameters such as number of jobs processed, average connect time. Simulation was carried out for timing both the access controller scheme and bit matrix scheme, The results of the simulation run bear the fact that the bit matrix scheme provides a faster method Six types of access were assumed to be permissible, three of the access types requiring shared lock and the rest requiring exclusive locks on the objects concerned, In addition the only type of operation allowed was assumed to be for accessing the objects. It is be noted that the time taken to check for security violation is but one of the factors for rating the security system. In general, various other factors such as cost of implementing the security system, the flexibility that offers enforcing security policies also have to be taken into account while comparing the security systems. Finally, in Chapter 6, a comparison of the security schemes are made. In conclusion the bit matrix approach is seen to provide the following features. (a) The time required to check if an access request should be honoured is very small. (b) The time required to find a11 users accessing an object viz, accountability is quite small. (c) The time required to find all objects accessible by a user is also quite small. (dl The scheme supports both decentralized and centralized authorization control. (e) Mechanism for enforcing delegation of access rights and revocation of access rights could be built in easily. ( f ) The scheme supports content-dependent, context-dependent controls and also provides a means for enforcing history-dependent control. Finally, some recommendations for further study in the field of Computer Database Security are presented.

The concept of Shifting the Balance of Care was first introduced to NHS Scotland in 2005 through the Kerr Report. The key messages from the report were to: ensure sustainable and safe local services, which are supported by the right skills, change the emphasis of care into the community, provide preventative reactive care, and fully integrate the system to tackle the changes, use technology more effectively, and involve the public in finding solutions to change. Following the report, a framework was developed which highlighted and prioritised eight areas of improvement. These areas for improvement are the focus by which this research examines if Operational Research (OR), specifically OR models, can have a positive impact in Shifting the Balance of Care. The research utilises underlying OR methodologies and methods and provides evidence from the literature of the ability of nine selected models to facilitate the Shift in the Balance of Care. A contributing factor to the research is the barriers to implementation of OR models into the NHS. With reference to the literature, the common barriers to implementation of OR models are categorised and used to provide direction to modellers where implementation barriers are more prevalent in some models than in others. The research also provides empirical evidence of three selected models’ (the Lean Methodology, Process Mapping and Simulation, developed over two Case Studies) ability to address and influence the prioritised Improvement Areas, with the addition of a newly developed model: SoApt. The development of SoApt follows the Principles of Model Development derived as a guide to modellers who wish to develop a new model. SoApt is also empirically explored in a Case Study and provides some evidence of the models ability to aid Decision-makers, faced with limited budgets, to choose between options which will Shift the Balance of Care. OR methods and methodologies are examined to ascertain the Roles of Models for each model explored in the Case Studies. Examination of the Roles of Models against the Improvement Areas provided evidence of a models’ ability to address more than one of the priority areas and that models can be used together or sequentially. In addition, with reference to OR methods and methodologies, a theoretical Evaluation Framework is proposed which suggests the User and User Satisfaction is key to the evaluation of a model’s success; positive experiences of the User and Use of the model may help to eliminate some of the barriers to implementation.

Μετά την πρώτη ενεργειακή κρίση την δεκαετία του ’70 κατά την οποία τα περιορισμένα αποθέματα ενέργειας προκάλεσαν την πρώτη σημαντική αύξηση στην τιμή της ενέργειας, η χρήση ενέργειας στα θερμοκήπια έχει γίνει κύριο ερευνητικό ζήτημα. Η ανάγκη για μείωση του ενεργειακού κόστους είναι σημαντική, γιατί η ενέργεια αποτελεί σημαντικό κλάσμα του συνολικού κόστους παραγωγής. Στις Μεσογειακές χώρες έχει υπολογιστεί ότι η χρήση ενέργειας για έλεγχο των συνθηκών περιβάλλοντος και ειδικότερα για τη θέρμανση, είναι 20% - 30% του συνολικού κόστους παραγωγής, ποσοστό το οποίο στις βορειότερες χώρες αυξάνεται. Ταυτόχρονα, με το έντονο ενδιαφέρον για το παγκόσμιο φαινόμενο του θερμοκηπίου και τις κλιματικές αλλαγές, η χρήση των συμβατικών καυσίμων είναι και πάλι στην πολιτική ατζέντα. Έτσι και η βιομηχανία θερμοκηπίων είναι αντιμέτωπη με οικονομική, πολιτική και κοινωνική πίεση για μείωση της χρήσης ενέργειας και βελτίωση της ενεργειακής απόδοσης των θερμοκηπίων μέσω τεχνολογικών καινοτομιών. Η κατανάλωση ενέργειας για τη θέρμανση του θερμοκηπίου αποτελεί ένα πολύ σοβαρό πρόβλημα διότι οι απώλειες του θερμοκηπίου σε θερμότητα λόγω των λεπτών τοιχωμάτων του και της κατασκευής του, είναι πολύ μεγάλες, 6-12 φορές μεγαλύτερες από εκείνες ενός συνήθους κτίσματος ίσου όγκου. Η θερμότητα παρέχεται στο θερμοκήπιο κυρίως μέσω συμβατικών συστημάτων θέρμανσης (συστήματα σωληνώσεων θερμού νερού, συστήματα θερμού αέρα) και σε περιορισμένη έκταση με χρήση ανανεώσιμων πηγών ενέργειας (ηλιακή, γεωθερμία, βιομάζα). Για να επιτευχθεί με αυτές τις μεθόδους η απαραίτητη θερμοκρασία στο επίπεδο των φυτών, το εσωτερικό του θερμοκηπίου πρέπει να θερμανθεί στην ίδια ή υψηλότερη θερμοκρασία από την επιθυμητή θερμοκρασία των φυτών με αποτέλεσμα την δημιουργία ισοθερμοκρασιακού κλίματος σε ολόκληρο το θερμοκήπιο (όλον κλίμα). Το αποτέλεσμα αυτής της πρακτικής σε όλες τις μελέτες που διεξάγονται είναι ότι, τα θερμοκήπια καταναλώνουν απαράδεκτα υψηλά ποσά ενέργειας σε σχέση με την ενέργεια που απορροφάται από τα φυτά, για να καλύπτουν τις αυξημένες ενεργειακές απώλειες που λόγω κατασκευής παρουσιάζουν. Στην παρούσα διατριβή αναπτύσσεται μια ολοκληρωμένη πρόταση για την δημιουργία ενός "ψυχρού θερμοκηπίου" στο οποίο τα φυτά θα λαμβάνουν απευθείας την ενέργεια που χρειάζονται προκειμένου να φτάσουν και να διατηρήσουν την επιθυμητή για την ανάπτυξή τους θερμοκρασία χωρίς να υπάρχει ανάγκη για αύξηση της θερμοκρασίας του αέρα του θερμοκηπίου. Για τον σκοπό αυτό χρησιμοποιείται σύστημα θέρμανσης με μικρού μήκους υπέρυθρη ακτινοβολία (NIR). Σε αυτά τα συστήματα η θερμότητα μεταδίδεται απευθείας από την πηγή στον δέκτη, στην προκειμένη περίπτωση στα φυτά και το έδαφος και το αποτέλεσμα είναι η δημιουργία ισοθερμοκρασιακού κλίματος μόνο στην περιοχή του φυτικού θόλου (τοπικό κλίμα). Ειδικότερα η παρούσα εργασία αντιμετωπίζει τη θερμική συμπεριφορά του θερμοκηπίου λαμβάνοντας υπόψη όλα τα ουσιαστικά θερμικά φαινόμενα που συμβαίνουν κατά την διάρκεια θέρμανσης (με συμβατικό και με σύστημα θέρμανσης με ακτινοβολία) και παρουσία καλλιέργειας. Γι αυτό τον λόγο δίνεται ιδιαίτερη βαρύτητα στην ανάπτυξη ενός μαθηματικού μοντέλου που προσομοιάζει επαρκώς τις κύριες διαδικασίες μεταφοράς θερμότητας μέσα στο θερμοκήπιο, το οποίο περιλαμβάνει ένα σύνολο λειτουργικών συνθηκών, και στο οποίο καθορίζονται με σχετική ακρίβεια οι παράγοντες που επηρεάζουν την θερμική συμπεριφορά του θερμοκηπίου. Το μοντέλο προσομοίωσης δίνει την δυνατότητα αξιόπιστης περιγραφής του περιβάλλοντος του θερμοκηπίου, και σαφούς εκτίμησης των ενεργειακών αναγκών του και με τις δυο τεχνικές θέρμανσης. Ετσι προσδιορίζεται το εξοικονομούμενο ενεργειακό όφελος που προκύπτει με τη χρήση συστήματος θέρμανσης με ακτινοβολία. Ο έλεγχος της ποιότητας του μοντέλου προσομοίωσης και η περαιτέρω βελτίωσή του γίνεται με σύγκριση των θεωρητικών αποτελεσμάτων με πειραματικά δεδομένα, η συλλογή και επεξεργασία των οποίων αποτελεί τον πυρήνα της έρευνας. Τα πειραματικά δεδομένα προέρχονται από πειράματα που διεξήχθησαν σε δύο πειραματικά θερμοκήπια συζευγμένα με αυτόματο μετεωρολογικό σταθμό, στα οποία εφαρμόζεται συμβατικό σύστημα θέρμανσης και θέρμανση με υπέρυθρη ακτινοβολία αντίστοιχα. Αυτό δίνει την δυνατότητα πιστοποίησης των δυνατοτήτων της θέρμανσης με ακτινοβολία και ποσοτικοποίησης του ενεργειακού οφέλους που επιτυγχάνεται. Συμπερασματικά, η συστηματική θεωρητική και πειραματική μελέτη ενός "ψυχρού" θερμοκηπίου με χρήση μικρού μήκους υπέρυθρης ακτινοβολίας (NIR) και ενός "θερμού θερμοκηπίου" με χρήση συμβατικού συστήματος θέρμανσης αναδεικνύουν το κύριο πλεονέκτημα της υπέρυθρης ακτινοβολίας, δηλαδή η θερμότητα να μεταδίδεται απευθείας από το σύστημα ακτινοβολίας στα φυτά και το έδαφος χωρίς να παρεμβάλεται ο αέρας του εσωτερικού περιβάλλοντος του θερμοκηπίου. Αυτό οδηγεί σε ομοιομορφία θέρμανσης του φυτικού θόλου και ταυτόχρονα σε σημαντική εξοικονόμηση ενέργειας της τάξεως του 40-50%. / After the first energy crisis in the seventies during which limited energy supplies led to an important increase in energy prices, greenhouse energy consumption has again become a major research issue. The energy cost reduction need is significant, since energy forms a substantial fraction of the total production costs. In Mediterranean countries it has been estimated that energy consumption for environment conditions control and more specifically for heating, consists 20% - 30% of total production cost, a percentage that is higher in northern countries. Moreover, due to the recent pronounced interest in the global greenhouse effect and climatic change, the use of fossil fuels is once again in the political agenda. Therefore the greenhouse industry is confronted with economical, political and social pressure to reduce energy usage and improve the greenhouse energy efficiency via technological innovations. Energy consumption for greenhouse heating represents a serious concern because greenhouse heat losses due to thin covers and construction specifics are 6-12 times higher than those of a common building of equal volume. Traditionally, thermal energy is transmitted to the greenhouse mainly through conventional heating systems (either by hot water circulation through a piping system or by air heaters) and, in a limited scale, through renewable energy sources (solar, geothermal, biomass). In order for the plants to reach required temperature through these methods, the greenhouse interior has to be heated to the same or even to a slightly higher temperature than the value targeted for the plants (entire climate). This practice results in extremely increased heat losses compared to the energy absorbed by plants, because of the increased energy losses due to construction specifications. The present thesis formulates a complete proposal for the creation of a "cold greenhouse" where plants will directly receive the needed energy in order to reach and preserve the desirable growth temperature without having to increase the internal greenhouse air temperature. The near infrared radiation (NIR) is used for this purpose. In the radiation system, heating is transmitted straight from the source to the receiver, in this particular case plants and soil. The result is an isothermal climate formation in the plant canopy (local climate). Specifically this study investigates the greenhouse thermal performance taking into account all the essential thermal phenomena that take place during heating (conventional and IR heating) and cultivation. For this reason, emphasis is given to the development of a mathematical model that simulates the main heating transfer procedures inside the greenhouse, takes into account a sum of operational conditions and determines all factors influencing the greenhouse thermal performance with relevant accuracy. The simulation model allows a credible description of greenhouse environment as well as a clear estimation of its energy needs with both heating systems. Thus the resulting energy saving by IR heating usage is determined. Quality control of the simulation model and its forward improvement is done by comparing the theoretical results with experimental data. Collecting and processing these data forms the research kernel. The experimental data correspond to experiments that took place in two experimental greenhouse connected with automatic meteorological station where conventional and IR heating have been used respectively. This method makes possible the identification of IR heating potential and quantification of energy saving. Concluding, the systematic theoretical and experimental study of a "cold" greenhouse using near IR heating, and of a "warm" greenhouse using conventional heating, proves the main advantage of IR heating that is that, the heat is directly transferred from the radiation system to the plants and the soil without interference of the internal greenhouse air. This leads to uniform heating of the plant canopy and at the same time to a significant energy saving of 40-50%.

Unternehmen stehen zunehmend vor der Herausforderung, dem drohenden Wissensverlust durch demografischen Wandel und Mitarbeiterabgang zu begegnen. In Zeiten voranschreitender Digitalisierung gilt es, große Datenmengen beherrschbar und nutzbar zu machen, mit dem Ziel, einerseits die Ressourceneffizienz innerhalb des Unternehmens zu erhöhen und anderseits den Kunden zusätzliche Dienstleistungen anbieten zu können. Vor dem Hintergrund, ein effizientes Qualitätsmanagement und eine vorausschauende Instandhaltung mit ein und demselben System zu realisieren, sind zunächst technologische Kennzahlen und die Prozessführung zu bestimmen. Im Bereich der intelligenten Instandhaltung ist es jedoch nicht immer möglich, Fehlerzustände von physischen Anlagen im Serienbetrieb als Datensatz abzufassen. Das bewusste Zulassen von Fehlern unter realen Produktionsbedingungen könnte zu fatalen Ausfällen bis hin zur Zerstörung der Anlage führen. Auch das gezielte Erzeugen von Fehlern unter stark kontrollierten Bedingungen kann zeitaufwendig, kostenintensiv oder sogar undurchführbar sein.