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EN
In the field of numerical research there are various approaches and methods for structures of porous materials modeling. The solution is the use of fractal models to develop the porous structure. In the case of modeling the geometry of natural (random) materials, there is a problem of compatibility of the FE model geometry and real one. This is a source of differences between the results of calculations and experimental ones. Application of 3D printing technology will allow to receive a real structure in a controlled manner, which exactly reflects the designed structure and is consistent with the geometry of the numerical model. An experimental research on the standard samples made of photopolymer resin using 3D printing technique was presented in the paper. The aim of the research was to determine the base material properties and, consequently, to select the constitutive model, which is necessary to carry out numerical analyses.
EN
This paper presents results of a research on the possibilities of applying 3D printed casting models for small production series as alternative to traditional tooling production on automated DisaMatch mould production lines. The main task was to verify and compare the dimensions of the 3D printed models before and after moulding process. The paper discusses main advantages and disadvantages of the 3D printing methods used like FDM (Fused Deposition Modeling)/FFF (Fused Filament Fabrication), SLA (stereolitography) and DPP (Daylight Polymer Printing). Measurement of casting model outside dimension change resulting from moulding sand friction on their surface was made with the use of GOM INSPECT software on the basis of 3D scans made with ATOS TripleScan optical scanner. Hardness of 3D printed models made of ABS, Z-ULTRAT, three different photopolymer resins (from FormLab and Liquid Crystal companies) was verified. The result of the research printed models usability for the foundry industry was presented.
PL
W artykule przedstawiono analizę czterech kryteriów mających wpływ na wybór technologii szybkiego prototypowania (RP) w procesie wytwarzania implantów kości pokrywy czaszki. Wzięto pod uwagę dokładność geometryczną, rodzaj wykorzystanego materiału, czas wykonania oraz koszty związane z ich wytworzeniem według następujących technologii RP: SLA (Stereolitography), FDM (Fused Deposition Modeling), PolyJet, SLS (Selective Laser Sintering), 3DP (Three Dimensional Printing).
EN
The article presents an analysis of four criteria which influence on the selection of rapid prototyping technology (RP) in the process of manufacturing skull bone implants. Were considered: the geometric accuracy, type of material, production time and costs related to their production of the following RP technologies: SLA (Stereolitography), FDM (Fused Deposition Modeling), PolyJet, SLS (Selective Laser Sintering), 3DP (Three Dimensional Printing).
PL
Głównym celem przeprowadzonej analizy była ocena przydatności metod szybkiego prototypowania do wykonania prototypów funkcjonalnych zębatej przekładni falowej. Elementem stwarzającym duże problemy konstrukcyjne i technologiczne w tego typu napędach jest cienkościenne koło podatne, mające drobnomodułowy wieniec zębaty. Wykonano więc modele fizyczne kół zębatych przekładni falowej i przeprowadzono dla nich precyzyjne pomiary profili zębów. Ukazano znaczące różnice pomiędzy modelami wytworzonymi z wykorzystaniem różnych metod szybkiego prototypowania w odniesieniu do ich wzorców teoretycznych. Ostatecznie określono, które z metod mogą być z powodzeniem stosowane do wytwarzania drobnomodułowych kół zębatych.
EN
The main purpose of conducted analysis was usefulness evaluation of the rapid prototyping methods to make functional prototypes of the harmonic drive. Element which causes serious structural and technological problems in these types of drives is the thin-walled flexspline, having small modular tooth rim. Thus, there were made physical models of harmonic drive’s gears and was conducted for them accurate measurement of tooth’s profiles. There were shown significant differences between the models made by different methods of quick prototyping in context of their theoretical profile. Finally it was determined which of the methods can be applied successfully to generate prototypes of gears with small modulus.
5
Content available Wykorzystanie druku 3D w zastosowaniach automotive
PL
W artykule scharakteryzowano najczęściej stosowane technologie druku 3D: metoda FFF/FDM, metoda SLA, metoda SLS oraz metoda CJP. Przedstawiono możliwości zastosowania druku 3D w przemyśle motoryzacyjnym oraz projektowaniu nowych elementów i części pojazdów. W części badawczej pracy zaprezentowano wybrane próbki elementów wydrukowanych w technologii druku 3D metodą FDM/FFF przy różnych parametrach druku w zakresie uzyskanej powierzchni i geometrii.
EN
The article presents the most commonly used 3D printing technologies: FFF / FDM method, SLA method, SLS method and CJP method. It presents the possibilities of 3D printing in the automotive industry and the design of new vehicle components and parts. In the research part of the work were presented selected samples of elements printed in FDM / FFF 3D printing technology with different printing parameters in the area of obtained surface and geometry.
EN
An expression of plants response to light availability is their shade tolerance which refers to the capacity of a given plant to tolerate low light levels. Survival in a shaded environment can determine phenotypic consequences at morphological and/or physiological levels and such changes may be crucial to survive in heterogeneous and variable conditions. However, the potential plastic response of a given plant trait may be large but the observed plasticity may be lowered by resource limitations or environmental stress factors. In this context, the aim of this research was to analyze morphological, anatomical and physiological leaf traits variations of Sesleria nitida Ten. growing in different light conditions. In particular, plants growing in open (PO) and shade (PU) conditions were analyzed. The results show a 35% higher specific leaf area (SLA) in PU than in PO due to a 94% larger leaf area (LA). The higher height and width of the central and the major lateral vascular bundle in PO than in PU contribute to a higher net photosynthesis (PN) in sun than in shade conditions. Moreover, the 33% higher ratio between respiration (RD) and PN (RD/PN) in PU than in PO highlights the greater proportion of the carbon consumed by RD in the shade population requiring a greater metabolic effort for growth and maintenance. S. nitida in the shaded environment might be favored by the soil pH being a neutro-basophilous species and the larger soil water content (SWC) and mineral content contributing to maintain a positive carbon balance in this limiting condition. The plasticity analysis for open vs. the understory plants (mean plasticity index = 0.32) highlights the leaf trait variations useful to maintain a positive carbon balance where light availability is the main limiting factor. Knowledge of the capacity of S. nitida to first colonize and then modify its phenotype in response to the shade condition can contribute to a better understanding of its ecology.
PL
Wstęp i cel: W pracy oceniono wpływ zastosowanej metody Rapid Prototyping w procesie kształtowania skomplikowanych struktur kostnych. Materiał i metody: Przedstawiono 6 urządzeń do kształtowania przyrostowego (SLS, SLA, FDM, 3DP, PolyJet oraz Bioplotter). Oceniono wpływ wymienionych metod na użyteczność zastosowania ich w procesie wykonania gotowych biomodeli. Wyniki: W wyniku przeprowadzonych badań stwierdzono iż każda metoda wydruku 3D ma swoje wady i zalety, które związane są z różnymi właściwościami materiałów, sposobami i czasem wykonania modeli oraz wymaganiami stawianymi gotowym modelom Wniosek: Pomimo różnorodności i dostępności wielu metod, żadna z nich nie dominuje w zastosowaniach medycznych.
EN
Introduction and aim: The aim of this study was assessed the effect of the method of Rapid Prototyping in the process of manufacturing biomodels. Material and methods: It demonstrates six Rapid Prototyping methods (SLS, SLA, FDM, 3DP, PolyJet and Bioplotter) and assessed influence this methods for manufacturing biomodels. Results: The research found that each method of 3D printing has its advantages and disadvantages that are associated with the different properties of the materials, methods of manufacturing models and requirements for the finished models Conclusion: Despite the diversity and availability of a variety of Rapid Prototyping methods, none of them dominates in medical applications.
EN
Nowadays, service providers offer a lot of IT services in the public or private cloud. Clients can buy various kinds of services, such as SaaS, PaaS, etc. Recently, Backup as a Service (BaaS), a variety of SaaS, was introduced there. At the moment, there are several different BaaS’s available to archive data in the cloud, but they provide only a basic level of service quality. In this paper, we propose a model which ensures QoS for BaaS and some methods for management of storage resources aimed at achieving the required SLA.This model introduces a set of parameters responsible for an SLA level which can be offered at the basic or higher level of quality. The storage systems (typically HSM), which are distributed between several Data Centers, are built based on disk arrays, VTL’s, and tape libraries. The RSMM model does not assume bandwidth reservation or control, but rather is focused on management of storage resources.
EN
Design work related to the implementation of new aerospace elements requires the use of 3D-CAD modelling techniques and rapid prototyping, which makes it possible to significantly accelerate the deployment of new solutions. The article presents the possibility of using some methods of rapid prototyping to produce the research model of a wheel hub forming part of the landing gear. Incremental rapid prototyping methods - JS (Jetting System), SLA (Stereolithography), FDM (Fused Depositing Modelling) - have been characterized with regard to the technology of executing a hub model, the parameters of the manufacturing apparatus, and comparing basic technical data of materials used in the analyzed processes. One of the elements of the process of prototyping was to process data in other equipment for rapid prototyping. This process consisted of the following steps: defining the parameters of model building, determining the appropriate model settings in the workspace of manufacturing equipment, editing the supporting structure, verifying the subsequent layers through the simulation of model building process, generating output numerical procedures for manufacturing equipment. Manufactured prototypes have been evaluated of dimensional accuracy with the use coordinate measuring machine. Also measured the surface roughness. Conducted studies were the basis to determine the applicability of various methods of rapid prototyping in the process of research and manufacturing aircraft wheel hub.
EN
The SERSCIS approach aims to support the use of interconnected systems of services in Critical Infrastructure (CI) applications. The problem of system interconnectedness is aptly demonstrated by 'Airport Collaborative Decision Making' (A-CDM). Failure or underperformance of any of the interlinked ICT systems may compromise the ability of airports to plan their use of resources to sustain high levels of air traffic, or to provide accurate aircraft movement forecasts to the wider European air traffic management systems. The proposed solution is to introduce further SERSCIS ICT components to manage dependability and interdependency. These use semantic models of the critical infrastructure, including its ICT services, to identify faults and potential risks and to increase human awareness of them. Semantics allow information and services to be described in a way that makes them understandable to computers. Thus when a failure (or a threat of it) is detected, SERSCIS components can take action to manage the consequences, including changing the interdependency relationships between services. In some cases, the components will be able to take action autonomously, e.g., to manage 'local' issues such as the allocation of CPU time to maintain service performance, or the selection of services where there are redundant sources available. In other cases the components will alert human operators so they can take action instead. The goal of this paper is to describe a Service Oriented Architecture (SOA) that can be used to address the management of ICT components and interdependencies in critical infrastructure systems.
EN
The rapid prototyping process was carried out on the example of an aircraft wheel hub and the key role of information operations performed at each stage was stressed. The design and its verification in a CAD system environment was completed. Parts were assembled and tested on their mutual cooperation. Basing on the model of 3D CAD a model of finite elements method was constructed and the tension distribution analysis was made. Tasks performed, supported by the CAD algorithms, made it possible to generate a finał version of the solid model. On its basis, an STL model constituting a base for the process of RP was developed and verified. Using software tools RP processes SLA and FDM were developed. The simulation of overlapping layers was carried in order to eliminate errors in the relevant physical processes. The numerical routines were generated for the apparatus : SLA 250/50 and uPrint. Prototypes of hub were made on the basis of stereolithography techniques and liquid plastic modeling. The coordinate measurements of models were carried out and errors specific to each method were analyzed.
PL
Przeprowadzono proces szybkiego prototypowania na przykładzie piasty koła samolotu podkreślając kluczową rolę operacji informatycznych wykonywanych na każdym jego etapie. Zrealizowano konstrukcję oraz jej weryfikację w środowisku systemu CAD. Dokonano złożenia części oraz sprawdzono ich wzajemną współpracę. W oparciu o model 3D CAD zbudowano model do analizy metodą elementów skończonych oraz przeprowadzono analizę rozkładu naprężeń. Wykonane zadania, wspierane przez algorytmy CAD, pozwoliły na wygenerowanie finalnej wersji modelu bryłowego. Na jego podstawie opracowano i zweryfikowano model STL stanowiący bazę dla procesu RP. Korzystając z narzędzi programowych RP opracowano procesy SLA oraz FDM. Przeprowadzono symulację nakładania kolejnych warstw celem wyeliminowania błędów we właściwym procesie fizycznym. Wygenerowano procedury obsługi numerycznej dla aparatury SLA 250/50 oraz uPrint. Wykonano prototypy piasty technikami stereolitografii oraz modelowania ciekłym tworzywem. Przeprowadzono pomiary współrzędnościowe modeli analizując błędy charakterystyczne dla każdej z metod. Procesy szybkiego prototypowania wspierane przez szereg narzędzi programowych pozwoliły wyselekcjonować i określić standardy zastosowania metod obliczeniowych do wykonywania modeli elementów konstrukcji. Zaostrzone wymogi w odniesieniu do konstrukcji lotniczych wykonywanych technikami RP wymuszają konieczność określenia szczególnych procedur obsługi numerycznej co stanowi przedmiot niniejszej pracy.
PL
W artykule przedstawiono rozważania teoretyczne i praktyczne na temat zarządzania usługami informatycznymi, korzyści płynące z wdrożenia narządzi wspierających odpowiednie procesy w firmie mające na celu ograniczanie kosztów funkcjonowania IT oraz zwiększenie efektywności działania oraz poprawy jakości oferowanych usług. Opisano standardy zarządzania usługami IT określanych jako ITIL z uwzględnieniem udokumentowanych obszarów wsparcia użytkownika i planowania dostarczania usług. Zwięźle określono cechy zaprezentowanych rozwiązań w zakresie zarządzania: incydentami, problemami, zmianami, konfiguracją i poziomem usług. Nawiązano do strategii zarządzania usługami z punktu widzenia firm: BMC Software, Microsoft i Hewlett Packard. Wspomniano o gotowych narzędziach stosowanych do zarządzania usługami IT firmy BMC Software oraz o zastosowaniu bazy danych konfiguracji CMDB, będącej punktem centralnym biblioteki ITIL.
EN
In this paper are presented theoretical and practical considerations about IT Service Management concepts, having as the aim limiting costs of functioning, enlargement working and the improvement of the offered IT Services quality using dedicated tools. The standards of IT Service Management were described as the ITIL with regard to supplied documentary evidence areas of Service Support and Service Delivery. The features of presented solutions in the range of: Incident Management, Problem Management, Change Management, Configuration Management and Service Level Management were precisely qualified. It was linked to the strategy of IT Service Management from the concept of companies: BMC Software, Microsoft and Hewlett Packard. It was remembered about ready tools applied to the ITSM according to BMC Software and applied configurations database CMDB, being the central point of ITIL library.
PL
Przedstawiono ideę porozumień w sprawie jakości obsługi oraz QoS. Omówiono różne podejścia do redagowania kontraktów SLA występujące w literaturze fachowej. Zaprezentowane koncepcje ułożono w zestaw reguł stanowiących instrukcję tworzenia kontraktów SLA. Ostatnią część artykułu stanowi przykad tekstu porozumienia w przypadku systemu telekomunikacyjnego opartego na technice WiMAX.
EN
The concept of service level agreements and quality of service is introduced in the paper. Different methodologies and approaches to edit Service Level Agreements, extracted from the technical literature, are presented in the paper. The presented concepts are composed in a set of rules that provide a complete instruction for defining service level agreements. The paper includes a complete text of a Service Level Agreement for a WiMAX telecommunication system.
EN
This paper presents results of prototyping of cementless THRA endoprosthesis with needle-palisade fixation system designed within the framework of the research project No 4 T07C 056 29. There are presented main instructions for modelling and prototyping according to Rogala's patents (Rogala, patents, 1999). CAD models present fragments of the needle-palisade fixation system, semicircle shaped fragments of the endoprosthesis and preprototype of total THRA endoprosthesis. The modelled elements were saved as STL format and printed with SLA. To verify the possibility of manufacturing of needle-palisade fixation system of the Rogala's cementless THRA endoprosthesis various samples of the fixation system were manufactured by one of direct metal manufacturing (DMM) technology - Selective Laser Melting (SLM). Fragments of needle-palisade fixation system were also manufactured by Electrical Discharge Machining (EDM). The paper presents the variety of designed samples and remarks concerning the producibility the needdle-palisade fixation manufacturing with the considered technologies.
PL
Przedstawiono problematykę pomiarów jakości sieci. Wymieniono liczne cele, dla których warto i należy prowadzić pomiary ruchu w sieciach IP. Omówiono zarówno pasywne, jak i aktywne techniki oceny jakości sieci IP oraz jej wybranych usług. Przedstawiono stan standaryzacji metrologii sieci IP oraz najpopularniejsze narzędzia związane z omawianą tematyką. W podsumowaniu wymieniono istotne zagadnienia pomiarów jakości sieci IP, które wciąż wymagają rozwiązania.
EN
The paper consist of description of all aspects related to IP network quality measurements in a state-of-the-art style. First, the motivation for IP network measurements is presented, next all existing approaches to IP networks quality evaluation, including as well active network testing as network monitoring (the passive approach) are briefly described. The relation between the network quality and the most important IP services has been outlined. Some standardization as well as common practice approaches to IP network measurements have been also presented. Finally open issues related to IP networks quality evaluation have been listed.
PL
Przedstawiono sieci VPN zorientowane na obsługę różnych aplikacji klienta. Omówiono konieczność sprzężenia z aplikacjami, typy i wymagania ruchowe oraz metody rozpoznawania aplikacji w sieciach. Na zakończenie przedstawiono przykładową platformę realizującą usługi VPN i umożliwiające definicję różnego poziomu obsługi (QoS) niezależnie od aplikacji.
EN
Article describes virtual private networks (VPNs) designed to support different customers' applications. There is shown the necessity of application awareness, types of applications, traffic requirements and methods of application recognition. Finally, there is shown an exemplary application aware platform supporting specific QoS per application.
PL
Przedstawiono najwazniejsze aspekty, na które należy zwrócić uwagę przy doborze systemu zarządzania. Przemyślenia oparto na systemie zarzadząnia Alcatel 5620 NM, który był odniesieniem do problemu zarządzania. Opisano najważniejsze cechy związane z zarządzaniem na wszystkich czterech poziomach modelu TMN, ze szczególnym uwzględnieniem zagadnień związanych z zarządzaniem usługami.
EN
The article is designed for these people, which would like to choice the most useful and reliable Network Management System for their network. It includes description of features, which is very important for NMS (Network Management System), based on leading NMS system called Alcatel 5620 NM.
PL
Opisano wymagania, jakie powinien spełniać system monitorowania i zarządzania jakością usług telekomunikacyjnych klasy operatorskiej. Opisano zaawansowany pakiet do zarządzania środowiskiem sieciowym dostawcy usług VitalSuiteSP firmy Lucent Technologies.
EN
The growing and competitive service provider market places new requirements on monitoring and managing the quality of services. In the paper the VitalSuiteSP - Lucent Technologies advanced performance management solution for service providers is presented.
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