Spelling suggestions: "subject:"[een] TWO-STAGE"" "subject:"[enn] TWO-STAGE""
121 |
亞洲主要機場的績效比較研究-資料包絡法的分析 / Efficiency evaluation of major airports in Asia-data envelopment analysis賴淑容, Lai, Shu Jung Unknown Date (has links)
This study adopt input orientation data envelopment Analysis approaches to evaluate the operational efficiency for major international airports in terms of the top 20 ranking by total passengers handling in Asia region in 2008. Unlike the most the other airport literature researches only using the one-stage DEA to measure the efficiency, in this study, two-stage, the extension of DEA, adding the concept of the intermediates product, separate the airport operation into airport capital side and airport capability side, is applied to evaluate the two-side efficiency of each airport under the assumption of constant returns to scale, variable returns to scale, scale efficiency and super efficiency model by employing four inputs, four intermediate products and two outputs.
The result of this study shows that the China Shenzhen Baoan airport is the best airport in overall technical efficiency in different stages. It indicates that the operation of small size airports (category by the passengers handling) are run more efficiency than the large one. In addition, by two-stage DEA analysis, the airport capital usage is better than in capacity utilization. It found that the China Beijing Capital airport is good in airport infrastructure usage but the capacity utilization is not enough. Finally, the number of increasing return scale airports are more than the decreasing return scale airports among Asia region (e.g. Taiwan Taoyuan airport), therefore, the expansions of facility and capacity in those increasing return scale airports are worthy to invest to promote the operational efficiency and its competitiveness.
|
122 |
Ein Nachfragesystem für dynamische Mikrosimulationsmodelle / A demand system for dynamic microsimulation modelsBrehe, Mathias January 2006 (has links)
Die Anwendung eines Mikrosimulationsmodells als Instrument der wirtschaftswissenschaftlichen Forschung erfreut sich großer Beliebtheit. Die Verwendung dieses Modelltyps hat vor allem zwei Gründe. Zum einen sind die in den letzten Jahren extrem gesunkenen Kosten der Informationsverarbeitung ursächlich für die mittlerweile häufige Verwendung. Zum anderen besitzt diese Analyseform Eigenschaften, die kein anderes Instrument aufweist. Insbesondere für die Abschätzung der Verteilungswirkungen von Steuer- und Transferreformen ist die Mikrosimulation eine nahezu ideale Methode. Durch die Einbindung eines Nachfragesystems kann sowohl das Anwendungsgebiet eines Mikrosimulationsmodells erweitert als auch dessen potentielle Leistungsfähigkeit
gesteigert werden. Die Arbeit hat im Wesentlichen die Beantwortung der Fragestellungen aus den folgenden zwei Fragenkomplexen zum Ziel:
- Wann ist die Einbindung eines Nachfragesystems in Mikrosimulationsmodelle sinnvoll und wie kann ein solches System in das eigentliche Mikrosimulationsmodell integriert werden?
- Welche Nachfragesysteme können aus den in Deutschland in Querschnittsform vorhandenen Mikrodatensätzen geschätzt werden und welche theoretischen Eigenschaften besitzen diese Systeme bzw. deren in einem zweistufigen Budgetierungsprozess einsetzbare Kombinationen? / The application of a microsimulation model as an instrument for economic research enjoys great popularity. The use of this type of model primarily has two reasons. In the first place the decreasing costs of data processing led to the frequent usage. Furthermore this type of analysis has unique characteristics compared to other instruments. Particularly microsimulation is an almost ideal method for the estimation of the impact of tax and allocative transfer reforms. With the integration of a demand system the field of application of a microsimulation model can be enlarged as well as its potential capacity increased. This paper has the aim to answer basically two batteries of questions:
- In what case the integration of a demand system in a microsimulation model is reasonable and how can such a system be integrated in the model?
- Which demand systems can be estimated from the microdata available in Germany and which characteristic properties do such systems offer, especially the combinations applicable in a two-stage budgeting environment?
|
123 |
Mobile Activity Coordination through Integrating Physical and Simulated Software AgentsLin, Shyh-ming 13 August 2007 (has links)
As wireless communication services get more and more pervasively available, mobile people can easily interact with service providers and handily communicate with each other through mobile devices. In the mobile environment, mobile users can plan their activity schedules and run their schedules with the assistance of mobile devices. When mobile users are engaged in their activities, they can instantly perceive contextual information and their activity schedules therefore tend to be context dependent, i.e., mobile users may alter their objectives and decision makings as soon as the environmental context varies. Besides, for a mobile user, once any exception happens, he/she is apt to adapt his/her activity schedule to reduce the impact of the exception. In the mobile environment, since the environmental resources are limited and can¡¦t satisfy all mobile users¡¦ demands, conflicts are likely to occur while mobile users plan, alter or adapt their personal activity schedules. This study concentrates itself on resolving the conflicts. This conflict problem is formulated as a multi-criteria context-dependent DCOP (distributed constraint optimization problem). This problem is complicated and highly dynamic, and the joint optimality to this problem might be time-variant. This study proposes an integrated agents system SPA and a novel problem solving approach 2S-DORA to enable mobile users to coordinate their activities to maintain optimality. The SPA, which integrates the Simulated and Physical Agents, is employed to enhance mobile users¡¦ sensory, analytic, reasoning and social abilities. The 2S-DORA takes advantage of the SPA abilities to help mobile users quickly and effectively adapt themselves to the context variations and to the exceptions. This study takes a traveling backpacker problem as an example to demonstrate how the proposed SPA and 2S-DORA contribute to solve the multi-criteria context-dependent DCOP. Five experiments finally are designed to evaluate the performance of the application of SPA and 2S-DORA.
|
124 |
Vuxna med enkelsidig genomgående läpp-, käk- ochgomspalt : Perceptuell röstbedömning med Stockholm Voice EvaluationApproach (SVEA)Isaksson, Kristoffer January 2012 (has links)
Läpp-, käk och gomspalt (LKG) kan medföra svårigheter med tal, artikulation och röst. Enligt tidigare forskning har vuxna individer behandlade för LKG liknande förekomst av röstavvikelser som kontrollpersoner utan spalt. Syftet med denna studie var att undersöka grad av röstavvikelser hos vuxna patienter behandlade för enkelsidig LKG och kartlägga eventuella samband mellan röstavvikelser och kirurgiska metoder för gomslutning, kön och operation med eller utan svalglambå samt jämföra röstresultat med data från individer utan LKG. Sjuttio patienter behandlade för enkelsidig genomgående LKG deltog i studien, varav 45 patienter hade opererats med gomslutning i en seans och 25 patienter hade opererats i två seanser. Elva av patienterna i patientgruppen hade genomgått svalglambåoperation. I studien ingick även en åldersmatchad kontrollgrupp med 63 individer utan LKG. Röstinspelningar utvärderades med perceptuell röstbedömning med Stockholm Voice Evaluation Approach (SVEA) av två erfarna logopeder. Skattning skedde individuellt av randomiserade och blindade inspelningar. Inter- och intrabedömarreliabilitet beräknades. Grad av avvikelse i röstkvalité var ca. 5/100 i patientgrupp och kontrollgrupp vilket är lägre jämfört med tidigare studier. “Knarr” fanns lägre i patientgruppen i jämförelse med kontrollgrupp. Skattningar av övriga röstparametrar skiljde sig inte mellan patientgrupp och kontrollgrupp. Patienter opererade med gomslutning i en eller två seanser hade inga skillnader i röstparametrar. Enstaka små skillnader fanns mellan könen. Ingen skillnad fanns mellan patienter som genomgått svalglambåoperation och de som inte gjort det. / Cleft lip and palate (CLP) may cause impairments in speech, articulation and voice. Treatment of patients with CLP include different types of palatoplasty. Recent studies have found a comparable prevalence rate of dysphonia in adult patients treated for CLP and controls without cleft. The purpose of this study was to investigate the rate of dysphonic deviation in adult patients treated for unilateral CLP and determine, if any, the relationship between voice quality outcome and differences in surgical procedures, gender, palatoplasty with or without pharyngeal flap surgery and compare the voice characteristics with age related normative data. Seventy patients treated for unilateral CLP with one- or two-stage palatoplasty participated in this study, of which 45 patientshad undergone one-stage palatoplasty and 25 patients two-stage palatoplasty. Eleven ofthe patients had also undergone pharyngeal flap surgery. Data from an age matched non-cleft group consisted of 63 participants. Sound recordings of participants' voices were perceptually assessed by two speech-language pathologists. Individual ratings of randomized and blinded sound recordings were performed. Inter- and intra-raterreliability was calculated. The study showed a lower degree of dysphonia in patients treated for unilateral CLP than earlier studies. Among patients treated for unilateral CLP and the non-cleft group, a degree of approximately 5/100 voice quality deviation was found. ”Vocal fry” was found significantly lower in patients treated for CLP than the non-cleft group. Measures of voice parameters did not differ significantly between patients and non-cleft groups. Patients that had undergone palatoplasty in one or two stages showed no significant differences in voice parameters. Minor statistical significance was found in a few of the measured voice parameters as related to gender. Between patients that had undergone pharyngeal flap surgery and those that had not no differences were found.
|
125 |
極超音速TSTOにおける衝撃波干渉・境界層剥離を伴う流れ場の解析北村, 圭一, KITAMURA, Keiichi, 小澤, 啓伺, OZAWA, Hiroshi, 花井, 勝祥, HANAI, Katsuhisa, 森, 浩一, MORI, Koichi, 中村, 佳朗, NAKAMURA, Yoshiaki 05 June 2008 (has links)
No description available.
|
126 |
Advanced Designs of Cancer Phase I and Phase II Clinical TrialsCui, Ye 13 May 2013 (has links)
The clinical trial is the most import study for the development of successful novel drugs. The aim of this dissertation is to develop innovative statistical methods to overcome the three main obstacles in clinical trials: (1) lengthy trial duration and inaccurate maximum tolerated dose (MTD) in phase I trials; (2) heterogeneity in drug effect when patients are given the same prescription and same dose; and (3) high failure rates of expensive phase III confirmatory trials due to the discrepancy in the endpoints adopted in phase II and III trials. Towards overcoming the first obstacle, we originally develop a hybrid design for the time-to-event dose escalation method with overdose control using a normalized equivalent toxicity score (NETS) system. This hybrid design can substantially reduce sample size, shorten study length, and estimate accurate MTD by employing a parametric model and adaptive Bayesian approach. Toward overcoming the second obstacle, we propose a new approach to incorporate patients’ characteristic using our proposed design in phase I clinical trials which considers the personalized information for patients who participant in the trials. To conquer the third obstacle, we propose a novel two-stage screening design for phase II trials whereby the endpoint of percent change in of tumor size is used in an initial screening to select potentially effective agents within a short time interval followed by a second screening stage where progression free survival is estimated to confirm the efficacy of agents. These research projects will substantially benefit both cancer patients and researchers by improving clinical trial efficiency and reducing cost and trial duration. Moreover, they are of great practical meaning since cancer medicine development is of paramount importance to human health care.
|
127 |
Optimization of recombinant bacterial fermentations for pharmaceutical productionBaheri, Hamid Reza 01 January 1998 (has links)
Two computer programs were developed and used to determine the optimum operating parameters of a fedbatch and a continuous two-stage process for fermentation of recombinant bacteria. The study was conducted in three phases: (a) developing two computer programs for simulation and optimization of the above processes, (b) conducting batch culture fermentations to verify the performance of the biokinetic model, and (c) conducting fedbatch and two-stage continuous fermentation experiments to closely examine the simulation and optimization results. The Miao and Kompala (1992) biokinetic model was used for simulation of the bacterial growth and cloned gene expression. The Pattern-Search method, developed by Hooke and Jeeves (1962), was incorporated in the programs to determine the optimum values of the parameters. Extensive studies of the optimization results showed 30-40% higher productivities for the two stage continuous process over the fedbatch process when using the same media in both processes. In addition, increasing the number of stages in the continuous two-stage process resulted in very limited improvement in the productivity of the process (10-12%). The information from the process optimization was then used to design batch, fedbatch nd two stage continuous experiments. Recombinant <i>E. coli </i>(strain BL21DE3) with an inducible gene (sensitive to IPTG, isopropyl-â-D-thiogalactopyranoside) was used throughout the experiments. The experimental results from the fedbatch and two stage continuous processes clearly showed good agreement with the simulation and optimization results $(\cong$15% deviation). The experiments also revealed that the maintenance of plasmid harboring cells over the long-term operation could be an important barrier in achieving the predicted high productivity in the two stage continuous process. Finally, in addition to computer programs for optimization of genetically modified microorganisms, a new computer program with a generic algorithm for optimization of multiple CFSTR fermentation with any kind of biokinetic model was developed. The program was used to optimize multiple CFSTRs with the cybernetic biokinetic model for the first time. Besides finding the optimum residence times for multiple CFSTRs operation, the effect of inaccuracies in different cybernetic model parameters on the overall productivity of the process was investigated. The simulation results illustrated that, a single CFSTR was more sensitive in its operation to inaccuracies in the biokinetic constants as compared to optimized CFSTRs in series (2-8 times more sensitive).
|
128 |
Performance Comparison of Selective Rake Receivers with CLEAN Algorithms in UWB SystemsYang, Siang-Yu 26 July 2006 (has links)
The Ultra-Wideband (UWB) channel is a dense multipath channel. The system performance and design complexity issues of selective-Rake receiver (SRake) are studied. Rake receiver has difficulties achieving desired system performance in the dense multipath environment. The main ideas of SRake receiver are to obtain the SNR level on known multipath channel and determine the desired number of Rake fingers. In the implementation of the SRake, the CLEAN algorithm is used in selecting the paths with relatively high energy. We can improve the performance of SRake receiver by increasing the accuracy of path selection. By the property of local maximum peak within the smaller partition, Two-Stage CLEAN algorithm acquires the more accurate delay time of multipath. In order to mitigate the sidelobe effect and noise interference, the key assumption in the Deng¡¦s Modified CLEAN algorithm is that using average amplitude around the considered data change as the criterion to determine if the data value is a true path. In this thesis, we investigate CLEAN, Two-Stage CLEAN and Deng¡¦s Modified CLEAN algorithm in three different systems including UWB-Impulse Radio, Pulse Radar and DS-UWB. From the performance comparison, it can be seen that the Two-Stage CLEAN algorithm that has the highest accuracy of path selection in UWB system.
|
129 |
Dynamic Food Demand in China and International Nutrition TransitionZhou, De 12 May 2014 (has links)
No description available.
|
130 |
Approches duales dans la résolution de problèmes stochastiquesLetournel, Marc 27 September 2013 (has links) (PDF)
Le travail général de cette thèse consiste à étendre les outils analytiques et algébriques usuellement employés dans la résolution de problèmes combinatoires déterministes à un cadre combinatoire stochastique. Deux cadres distincts sont étudiés : les problèmes combinatoires stochastiques discrets et les problèmes stochastiques continus. Le cadre discret est abordé à travers le problème de la forêt couvrante de poids maximal dans une formulation Two-Stage à multi-scénarios. La version déterministe très connue de ce problème établit des liens entre la fonction de rang dans un matroïde et la formulation duale, via l'algorithme glouton. La formulation stochastique discrète du problème de la forêt maximale couvrante est transformée en un problème déterministe équivalent, mais du fait de la multiplicité des scénarios, le dual associé est en quelque sorte incomplet. Le travail réalisé ici consiste à comprendre en quelles circonstances la formulation duale atteint néanmoins un minimum égal au problème primal intégral. D'ordinaire, une approche combinatoire classique des problèmes de graphes pondérés consiste à rechercher des configurations particulières au sein des graphes, comme les circuits, et à explorer d'éventuelles recombinaisons. Pour donner une illustration simple, si on change d'une manière infinitésimale les valeurs de poids des arêtes d'un graphe, il est possible que la forêt couvrante de poids maximal se réorganise complètement. Ceci est vu comme un obstacle dans une approche purement combinatoire. Pourtant, certaines grandeurs analytiques vont varier de manière continue en fonction de ces variations infinitésimales, comme la somme des poids des arêtes choisies. Nous introduisons des fonctions qui rendent compte de ces variations continues, et nous examinons dans quels cas les formulations duales atteignent la même valeur que les formulations primales intégrales. Nous proposons une méthode d'approximation dans le cas contraire et nous statuons sur la NP complétude de ce type de problème.Les problèmes stochastiques continus sont abordés via le problème de sac à dos avec contrainte stochastique. La formulation est de type ''chance constraint'', et la dualisation par variable lagrangienne est adaptée à une situation où la probabilité de respecter la contrainte doit rester proche de $1$. Le modèle étudié est celui d'un sac à dos où les objets ont une valeur et un poids déterminés par des distributions normales. Dans notre approche, nous nous attachons à appliquer des méthodes de gradient directement sur la formulation en espérance de la fonction objectif et de la contrainte. Nous délaissons donc une possible reformulation classique du problème sous forme géométrique pour détailler les conditions de convergence de la méthode du gradient stochastique. Cette partie est illustrée par des tests numériques de comparaison avec la méthode SOCP sur des instances combinatoires avec méthode de Branch and Bound, et sur des instances relaxées.
|
Page generated in 0.3997 seconds