83 research outputs found
Optimal design of curved folded plates
The plated structures are one of the most frequently used engineering, structures. The object of this research work is the optimal design of curved folded plates. This work is an ongoing investigation. There are various solution methods to analyze this type of structures. Here the finite strip method is used. At first single load condition is considered, but later the multiple load conditions are used for the design. The base formulation is a minimum volume design with displacement constraint what is represented by the compliance. For the multiple loading two equivalent topology optimization algorithms can be elaborated: minimization of the maximum strain energy with respect to a given volume or minimization of the volume of the structure subjected to displacement constraints. The numerical procedures are based on iterative formulas which is formed by the use of the first order optimality condition of the Lagrangian-functions. The application is illustrated by numerical examples
Mesterséges intelligencia és gépi látás eszközök vizsgálata az Ipar 4.0 rendszerek fejlesztési környezetében
ElĂ©rkeztĂĽnk a negyedik ipari forradalom (Ipar 4.0) kialakulásához, ami számos Ăşjdonságot, lehetĹ‘sĂ©get, problĂ©mát, elvárásokat Ă©s követelmĂ©nyeket hoz magával. Ahhoz, hogy minĂ©l sikeresebben alkalmazzuk az Ipar 4.0-t Ă©s kĂ©pesek legyĂĽnk standardizálni, Ăşjszerű gondolatokra Ă©s kutatási tevĂ©kenysĂ©gekre van szĂĽksĂ©g. Ez az Ăşj ipari forradalom nem csak a technikai ĂşjĂtásokrĂłl szĂłl, hanem hogy a jelenleg rendelkezĂ©sre állĂł technolĂłgiákat kĂ©pesek legyĂĽnk összekötni, ezekkel kapcsolatot teremtve az ipar Ă©s egyĂ©b ágazatok között, illetve integrálni a logisztikába a legkorszerűbb informatikai fejlesztĂ©seket
Analysis of solder joint failures arisen during the soldering process
The paper gives an overview of the analysis methods applied by electronic failure analysis laboratories for detection, localization and in depth analysis of solder joint failures. The paper focuses on failures that arise during the soldering process. Besides the analysis methods case studies and a few failure modes together with their inspection and root causes are also described. Optical microscopy is used for sample documentation and failure localization. X-ray microimaging can be applied to non-destructively inspect hidden joints i.e. BGA (ball grid array), flip-chip, CSP (chip scale package) bump and micro-wire. It can be also used to measure the amount of solder or voids in the joints. Inspection of PWB (printed wiring board) tracks and via metallization can also be carried out by these systems. SAM (scanning acoustic microscopy) is an effective tool to detect and to visualize delaminations or cracks inside electronics packages or assemblies. As failures are in most cases retraceable to material or compo
sitional problems, SEM (scanning electron microscopy) together with electron microprobe analysis can be applied to find the root cause of failures.
Thorough analysis of a broken solder joint, wetting problem of cut surfaces, delamination and insufficient through-hole solder joints are presented in the paper. By these case studies not only the failure analysis procedure can be demonstrated, but also the root causes of these failures are revealed
Optimal design accounting for uncertainty in loading amplitudes: A numerical investigation
A numerical investigation is performed addressing the optimal design of stiff structures accounting for uncertainty in loading amplitudes. A minimum volume problem is endowed with a stochastic compliance constraint handling normal distributions and solved adopting mathematical programming. The formulation, originally conceived for a single load case, is extended to handle multiple load cases. Numerical simulations are performed to test the proposed algorithms, pointing out features of the numerical procedures and peculiarities of the stochastic-based optimal solutions achieved for different values of the second-order moments. Comparisons with respect to conventional deterministic layouts are provided as well
A GDP és GNI közötti eltérés hazai és régiós alakulása
A globalizáciĂł elĹ‘retörĂ©sĂ©vel a termelĂ©si tĂ©nyezĹ‘k határon átnyĂşlĂł mozgása miatt a hazai gazdaság termelĂ©se Ă©s a termelĂ©s által generált rezidenseknek jutĂł elsĹ‘dleges jövedelem elnyĂlik egymástĂłl. A GDP-GNI közötti eltĂ©rĂ©s megmutatja a hazai gazdaság teljesĂtmĂ©nye Ă©s a gazdaság egyes szektorainak jutĂł elsĹ‘dleges jövedelem közötti kĂĽlönbsĂ©get, illetve hasznos informáciĂłt ad az ország felhalmozott nettĂł kĂĽlföldi kötelezettsĂ©g-állományának folyĂł terheirĹ‘l. Tanulmányunkban bemutatjuk a GDP-GNI rĂ©s alakulását befolyásolĂł tĂ©nyezĹ‘ket az elmĂşlt Ă©vekben, majd a rendelkezĂ©sre állĂł adatokat ágazati Ă©s országbontásban vizsgálva nĂ©zzĂĽk meg, hogyan változott a gazdaság egyes szektorainak jövedelme. A nemzetközi folyamatok Ă©s rĂ©giĂłs tendenciák elemzĂ©sĂ©vel vizsgáljuk a GDP Ă©s GNI közötti eltĂ©rĂ©s Ă©s a gazdaságok fejlettsĂ©ge közötti összefĂĽggĂ©st, majd igyekszĂĽnk feltĂ©rkĂ©pezni azokat az irányvonalakat, amelyek a hazai GDP Ă©s GNI közötti eltĂ©rĂ©st rövid, illetve hosszĂş távon meghatározzák. MegállapĂtjuk, hogy a GDP-GNI rĂ©s a kĂĽlföldi tulajdonĂş vállalatok jövedelmĂ©nek várhatĂł emelkedĂ©se miatt rövid távon növekedhet, hosszĂş távĂş alakulása pedig jelentĹ‘sen fĂĽgg attĂłl, hogy a magyar gazdaság nyugati országokhoz törtĂ©nĹ‘ felzárkĂłzása kĂĽlföldi vagy belföldi forrásokbĂłl valĂłsul meg
A kreatĂv tanulás Ă©s tanĂtás szolgálatában GamifikáciĂłs Ă©rtĂ©kelĂ©s a saját fejlesztĂ©sű MotivApp applikáciĂłval
A Best-Worst Scaling preferenciaértékelő eljárás "object" esetének bemutatása = Presentation of the „object” case of the Best–Worst Scaling preference valuation method
A fogyasztĂłi preferenciák vizsgálatához alkalmazott eljárás megválasztása mĂ©g manapság is rendkĂvĂĽl nehĂ©z döntĂ©st kĂ©pvisel a kutatásokban. A feltárt preferencia (SP) jellegű adatokon alapulĂł mĂłdszerek használatakor a kutatĂłk elsĹ‘dleges cĂ©lja az, hogy minĂ©l eredmĂ©nyesebben tudják csökkentetni a hipotetikus kontextus okozta torzĂtĂł hatást, mindemellett egyre több informáciĂłhoz jussanak a felmĂ©rĂ©s rĂ©sztvevĹ‘ivel kapcsolatosan. A tanulmányban a nemzetközi szĂntĂ©ren Best–Worst ScalingkĂ©nt (BWS) ismerttĂ© vált preferenciaĂ©rtĂ©kelĹ‘ eljárás „object” esetĂ©t mutatjuk be, ami több elĹ‘nyös tulajdonsággal rendelkezik más hasonlĂł mĂłdszerekhez kĂ©pest. Az elsĹ‘ rĂ©szben a BWS elmĂ©leti hátterĂ©t Ă©s kĂsĂ©rleti elrendezĂ©sĂ©nek megvalĂłsĂtási lĂ©pĂ©seit ismertetjĂĽk, majd a szĂĽksĂ©ges adatbázis-formátumot fogjuk bemutatni. Ezt követĹ‘en szimuláciĂłval előállĂtott adatok segĂtsĂ©gĂ©vel az elemzĂ©s „számĂtásos” megközelĂtĂ©sĂ©nek lĂ©pĂ©seit vezetjĂĽk vĂ©gig, ábrákkal Ă©s Ă©rtelmezĂ©sekkel kiegĂ©szĂtve, a tanulmány legvĂ©gĂ©n pedig limitált kitekintĂ©st nyĂşjtunk a „modellezĂ©si” megközelĂtĂ©sre. Tanulmányunk segĂtsĂ©gĂ©vel az olvasĂłnak lehetĹ‘sĂ©ge nyĂlik egy több terĂĽleten is viszonylag könnyen alkalmazhatĂł preferenciaĂ©rtĂ©kelĹ‘ eljárás megismerĂ©sĂ©re Ă©s elsajátĂtására. = Even nowadays, the choice of the method used to investigate consumer preferences represents a difficult decision in research. When using methods based on stated preference (SP) data, the primary goal of researchers is to reduce the distorting effect caused by the hypothetical context as effectively as possible, and also to obtain more and more information about the survey participants. In the study, we present the „object” case of the preference valuation method known internationally as Best–Worst Scaling (BWS), which has several advantageous properties compared to other similar methods. In the first part, the theoretical background of the BWS and the implementation steps of its experimental design will be described, and then the necessary database format will be presented. After that, with the use of data generated by simulation, we guide you through the steps of the „counting” approach of the analysis, supplemented with figures and interpretations, and at the end of the study, we provide a limited overview of the „modeling” approach. With the help of our study, the reader has the opportunity to learn about and master a preference valuation method that can be applied relatively easily in several areas
Spray-dried indomethacin-loaded polymeric micelles for the improvement of intestinal drug release and permeability
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