To see the other types of publications on this topic, follow the link: OPTIMAL NUMBERS.
Dissertations / Theses on the topic 'OPTIMAL NUMBERS'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'OPTIMAL NUMBERS.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Fransson, Jonas. "Lower ramification numbers of wildly ramified power series." Thesis, Linnéuniversitetet, Institutionen för matematik (MA), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-35313.
Full textAbstract:
In this thesis we study lower ramification numbers of power series tan- gent to the identity that are defined over fields of positive characteristics. Let f be such a series, then f has a fixed point at the origin and the corresponding lower ramification numbers of f are then, up to a constant, the multiplicity of zero as a fixed point of iterates of f. In this thesis we classify power series having ‘small’ ramification numbers. The results are then used to study ramification numbers of polynomials not tangent to the identity. We also state a few conjectures motivated by computer experiments that we performed.
2
Li, Tianjian. "On Optimal Survivability Design in WDM Optical Networks under Scheduled Traffic Models." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1173975555.
Full text
3
Pettersson, Lars, and Johansson Christoffer Lundell. "Ant Colony Optimization - Optimal Number of Ants." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229764.
Full textAbstract:
The focus of this thesis paper is to study the impact the number of ants has on the found solution of the Ant Colony Optimization (ACO) metaheuristic when solving the Traveling Salesman Problem. The goal was to find out how the length of the computed tours change for different amounts of ants within a limited number of iterations. To study this, three well known versions of the ACO algorithm were implemented and tested: Min-Max Ant System (MMAS), Elitist Ant System (EliteAS) and Ranked Ant System (RankedAS). The results showed trends that were consistent over several test cases. EliteAS and RankedAS which both utilize specialist ants showed clear signs that the number of specialists had a large influence on the length of solutions. Meanwhile, normal ants did not affect the solutions as much. MMAS and EliteAS only had a small variation on the answer, with lower amount of ants being more favorable. On the other hand, RankedAS performed better by a large margin when working with five specialists and a number of ants equaling the number of cities in the problem.Målet med denna rapport var att studera hur antalet myror som används av Ant Colony Optimization (ACO) påverkar resultatet vid lö- sandet av Traveling Salesman Problem (TSP). Hur ändras lösningens längd med olika antal myror, när antalet iterationer som får användas är begränsat? För att få fram ett svar på frågan implementerades och testades tre välkända ACO algoritmer: Min-Max Ant System (MMAS), Elitist Ant System (EliteAS) och Ranked Ant System (RankedAS). Efter implementering och utförlig testning så uppdagades trender som var konsistenta över flera testfall. För EliteAS och RankedAS, som bå- da förlitar sig på specialiserade myror, hade antalet specialister en stor påverkan på den funna längden. Normala myror hade istället en liten påverkan på slutresultatet. För MMAS och EliteAS så var skillnaden minimal, med en viss favör mot ett lägre antal myror. RankedAS hade en motsatt trend och hade bäst resultat med fem specialister och lika många normala myror som antalet städer i TSP instansen.
4
Bayless, Mark D. "Improving optical character recognition accuracy for cargo container identification numbers." [Denver, Colo.] : Regis University, 2010. http://adr.coalliance.org/codr/fez/view/codr:139.
Full text
5
Kouhbor, Shahnaz University of Ballarat. "Optimal number and placement of network infrastructure in wireless networks." University of Ballarat, 2007. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12762.
Full textAbstract:
Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
6
Kouhbor, Shahnaz. "Optimal number and placement of network infrastructure in wireless networks." Thesis, University of Ballarat, 2007. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/65892.
Full textAbstract:
Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
7
Kouhbor, Shahnaz. "Optimal number and placement of network infrastructure in wireless networks." University of Ballarat, 2007. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14597.
Full textAbstract:
Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
8
Barkino, Iliam, and Öman Marcus Rivera. "Enough is Enough : Sufficient number of securities in an optimal portfolio." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298462.
Full textAbstract:
This empirical study has shown that optimal portfolios need approximately 10 securities to diversify away the unsystematic risk. This challenges previous studies of randomly chosen portfolios which states that at least 30 securities are needed. The result of this study sheds light upon the difference in risk diversification between random portfolios and optimal portfolios and is a valuable contribution for investors. The study suggests that a major part of the unsystematic risk in a portfolio can be diversified away with fewer securities by using portfolio optimization. Individual investors especially, who usually have portfolios consisting of few securities, benefit from these results. There are today multiple user-friendly software applications that can perform the computations of portfolio optimization without the user having to know the mathematics behind the program. Microsoft Excel’s solver function is an example of a well-used software for portfolio optimization. In this study however, MATLAB was used to perform all the optimizations. The study was executed on data of 140 stocks on NASDAQ Stockholm during 2000-2014. Multiple optimizations were done with varying input in order to yield a result that only depended on the investigated variable, that is, how many different stocks that are needed in order to diversify away the unsystematic risk in a portfolio.Osäker på examinatorns namn, tog namnet på den person som skickade mejl om betyg.
9
Ju, Heongkyu. "Photon-number squeezing of femtosecond optical pulses in nonlinear media." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249632.
Full text
10
Kitagawa, Akira. "Manipulation of Photon Number-States and Its Linear Optical Realization." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147620.
Full text
11
Frigui, Hichem. "New approaches for robust clustering and for estimating the optimal number of clusters /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9842528.
Full text
12
Hathaway, John Ellis. "Determining the Optimum Number of Increments in Composite Sampling." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/425.
Full textAbstract:
Composite sampling can be more cost effective than simple random sampling. This paper considers how to determine the optimum number of increments to use in composite sampling. Composite sampling terminology and theory are outlined and a model is developed which accounts for different sources of variation in compositing and data analysis. This model is used to define and understand the process of determining the optimum number of increments that should be used in forming a composite. The blending variance is shown to have a smaller range of possible values than previously reported when estimating the number of increments in a composite sample. Accounting for differing levels of the blending variance significantly affects the estimated number of increments.
13
Akers, Allen. "Determination of the Optimal Number of Strata for Bias Reduction in Propensity Score Matching." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc28380/.
Full textAbstract:
Previous research implementing stratification on the propensity score has generally relied on using five strata, based on prior theoretical groundwork and minimal empirical evidence as to the suitability of quintiles to adequately reduce bias in all cases and across all sample sizes. This study investigates bias reduction across varying number of strata and sample sizes via a large-scale simulation to determine the adequacy of quintiles for bias reduction under all conditions. Sample sizes ranged from 100 to 50,000 and strata from 3 to 20. Both the percentage of bias reduction and the standardized selection bias were examined. The results show that while the particular covariates in the simulation met certain criteria with five strata that greater bias reduction could be achieved by increasing the number of strata, especially with larger sample sizes. Simulation code written in R is included.
14
Neeranartvong, Weerachai. "Utilizing optimal nulling to increase the number of supported wireless users over conventional beamforming." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123042.
Full textAbstract:
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 101-102).
The rapid growth of the number of devices and the gigantic amount of data present challenges to the healthy growth of telecommunication systems that is needed to support high-density environments. Multiple-antenna systems are deployed at base stations to support multiple users simultaneously on the same frequency, taking advantage of beamforming spatial diversity. In this thesis, we explore the application of antenna nulling in providing additional user coverage (as in increased number of supported users) over conventional beamforming. We consider, as a special case to validate the idea, the uplink line-of- sight narrowband transmission of a single base station equipped with uniform circular antenna array (UCA) through conventional, complete nulling, and optimal beamformers. We demonstrate, numerically and analytically, the average number of active users and outage probabilities under different beamformers, given a minimally acceptable signal-to-interference-and-noise (SINR) threshold and additional power margin. Variations of the antenna radius, number of antenna elements, and low- and high-SINR threshold are considered. We have shown a significant gain associated with the use of optimal beamformers instead of conventional beamformers. We discover that the improvements largely depend on the SINR threshold and is limited by the number of antenna elements for the unsaturated array and by the antenna aperture for the saturated array.
by Weerachai Neeranartvong.
M. Eng.
M.Eng. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science
15
Hatziathanasiou, Thomas N. "Optimum symmetrical number system phase sampled direction finding antenna architectures." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA349707.
Full textAbstract:
Thesis (M.S. in Applied Physics) Naval Postgraduate School, June 1998."June 1998." Thesis advisor(s): Phillip E. Pace, David D. Cleary. Includes bibliographical references (p. 191-192). Also available online. Mode of access: World Wide Web.
16
Nemaranzhe, Lutendo. "A mathematical modeling of optimal vaccination strategies in epidemiology." University of the Western Cape, 2010. http://hdl.handle.net/11394/3065.
Full textAbstract:
Magister Scientiae - MScWe review a number of compartmental models in epidemiology which leads to a nonlinear system of ordinary differential equations. We focus an SIR, SEIR and SIS epidemic models with and without vaccination. A threshold parameter R0 is identified which governs the spread of diseases, and this parameter is known as the basic reproductive number. The models have at least two equilibria, an endemic equilibrium and the disease-free equilibrium. We demonstrate that the disease will die out, if the basic reproductive number R0 < 1. This is the case of a disease-free state, with no infection in the population. Otherwise the disease may become endemic if the basic reproductive number R0 is bigger than unity. Furthermore, stability analysis for both endemic and disease-free steady states are investigated and we also give some numerical simulations. The second part of this dissertation deals with optimal vaccination strategy in epidemiology. We use optimal control technique on vaccination to minimize the impact of the disease. Hereby we mean minimizing the spread of the disease in the population, while also minimizing the effort on vaccination roll-out. We do this optimization for the cases of SIR and SEIR models, and show how optimal strategies can be obtained which minimize the damage caused by the infectious disease. Finally, we describe the numerical simulations using the fourth-order Runge-Kutta method. These are the most useful references: [G. Zaman, Y.H Kang, II. H. Jung. BioSystems 93, (2008), 240 − 249], [K. Hattaf, N. Yousfi. The Journal of Advanced Studies in Biology, Vol. 1(8), (2008), 383 − 390.], [Lenhart, J.T. Workman. Optimal Control and Applied to Biological Models. Chapman and Hall/CRC, (2007).], [P. Van den Driessche, J. Watmough. Math. Biosci., 7, (2005)], and [J. Wu, G. R¨ost. Mathematical Biosciences and Engineering, Vol 5(2), (2008), 389 − 391].
South Africa
17
Sandberg, Fanny. "Is There an Optimal Number of Names and Persons to Include in a Case Study?" Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-32627.
Full text
18
Kastner, Jeffrey F. "Far-field radiated noise mechanisms in high reynolds number and high-speed jets." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1181753004.
Full text
19
Kryvobok, Valeria, Валерія Кривобок, Микита Глущенко, Nikita Hlushchenko, and Huang Chenfan. "Method for calculating the optimal number of loading and uploading points of the airport cargo warehouse." Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/51160.
Full textAbstract:
1. Transport terminals: purpose, attributes, functions. URL: https://dsl-ua.com/en/2019/06/24/ru-transportnyie-terminalyi-naznachenie-atributyi-funktsii/
2. Calculation of parameters of service systems for passenger and freight transportation. URL:http://repo.ssau.ru/bitstream/Metodicheskie-materialy/Raschet-parametrov-sistem-obsluzhivaniya-passazhirskih-i-gruzovyh-perevozok-Elektronnyi-resurs-ucheb-posobie.pdf
3. Transportation of perishing goods. URL:https://files.stroyinf.ru/Data2/1/4293826/4293826395.htm#i483584The cargo complex of the airport is a warehouse of temporary storage of cargo arriving and departing by planes serviced at the airport. The airport operator or handling company services the cargo complex. The cargo terminal carries out ground handling of cargo transported by foreign and domestic airlines, as well as provides freight forwarding, customs brokerage and warehousing services. The airport cargo complex helps you to solve the issues of transportation, warehousing and customs clearance of goods, as well as provides professional advice on all related issues. Cargo warehouses of a modern airport are complex engineering structures, most of which are mechanized and automated. They are equipped with special vehicles and means of mechanization, weighing, transportation and storage of goods and mail, including: stationary and self-propelled lifting equipment and mechanisms; weight measuring equipment; means of transportation of goods and mail; means of loading and unloading cargo and mail to / from the aircraft; means of loading and unloading containers (pallets) to / from the aircraft; engineering and technical means of aviation security; means of detecting radioactive and explosive substances; means of communication, information, radio broadcasting.
Вантажний комплекс аеропорту - це склад тимчасового зберігання вантажів, що прибувають і вилітають літаками, що обслуговуються в аеропорту. Оператор аеропорту або обробна компанія обслуговує вантажний комплекс. Вантажний термінал здійснює наземне обслуговування вантажів, що перевозяться закордонними та вітчизняними авіакомпаніями, а також забезпечує експедирування вантажів, митний брокер і складські послуги. Вантажний комплекс аеропорту допомагає вирішити питання транспортування, складування та митного оформлення вантажів, а також надає професійні консультації з усіх супутніх питань. Вантажні склади сучасного аеропорту - це складні інженерні споруди, більшість з яких механізовані та автоматизовані. Вони оснащені спеціальними транспортними засобами та засобами механізації, зважування, транспортування та зберігання вантажів та пошти, в тому числі: стаціонарними та самохідними підйомними обладнаннями та механізмами; обладнання для вимірювання ваги; засоби перевезення вантажів та пошти; засоби завантаження та вивантаження вантажу та пошти до / з повітряного судна; засоби завантаження та розвантаження контейнерів (піддонів) до / з літака; інженерно-технічні засоби авіаційної безпеки; засоби виявлення радіоактивних та вибухонебезпечних речовин; засоби зв'язку, інформації, радіомовлення.
20
Macavei, Diana. "A Game Theoretic Approach to the Problem of Determining the Optimal Number of Years of Education." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1303158106.
Full text
21
Singer, Ethan Lloyd "Mendel." "Modeling the mail survey response pattern and determining the optimal number of questionnaires: A Bayesian approach." Case Western Reserve University School of Graduate Studies / OhioLINK, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=case1055343499.
Full text
22
Asudegi, Mona. "Optimal number and location of Bluetooth sensors for travel time data collection in netwroks [i.e. networks]." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9400.
Full textAbstract:
Thesis (M.S.) -- University of Maryland, College Park, 2009.Thesis research directed by: Dept. of Civil Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
23
Khwambala, Patricia Helen. "The importance of selecting the optimal number of principal components for fault detection using principal component analysis." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/11930.
Full textAbstract:
Includes summary.Includes bibliographical references.
Fault detection and isolation are the two fundamental building blocks of process monitoring. Accurate and efficient process monitoring increases plant availability and utilization. Principal component analysis is one of the statistical techniques that are used for fault detection. Determination of the number of PCs to be retained plays a big role in detecting a fault using the PCA technique. In this dissertation focus has been drawn on the methods of determining the number of PCs to be retained for accurate and effective fault detection in a laboratory thermal system. SNR method of determining number of PCs, which is a relatively recent method, has been compared to two commonly used methods for the same, the CPV and the scree test methods.
24
Teotia, Seemant. "Influence of the Number of Degrees of Freedom on the Capacity of Incoherent Optical Fiber Communication Systems." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/27497.
Full textAbstract:
The purpose of this dissertation is to find the channel capacity in optical fiber communication systems when incoherent detection is used with single (polarization filtering) and two-polarizations (no polarization filtering).
Optical fiber systems employ photodetectors that convert optical intensity to electrical current. Bandpass vector fields may be represented by four orthogonal baseband components corresponding to two quadrature phases and two orthogonal polarizations. Intensity is proportional to the sum of the squares of these four components. In the case of a coherent receiver, a strong optical local oscillator (in phase and with same polarization as the signal) is added to the signal prior to the photodetector. This results in the removal of the quadrature phase and polarization components, and reduces to the one degree of freedom (DOF) case of signal plus local oscillator shot noise for which the Shannon channel capacity formula applies. Electrical noise following the photodetector may also be neglected if there is an optical amplifier before the photodetector in the receiver. The amplifier introduces amplified spontaneous emission noise containing both quadrature phase components and both polarizations (4 DOFs), but the 2 DOF case would result if a polarization filter were used. Although the 1 and 2 DOF cases are of less practical interest than the 4 DOF case, they provide useful benchmarks for comparing performance limits.
We evaluate both spectral efficiency limits (bps/Hz) in the limit of high and low SNR for the 1,2 and 4 DOF cases and also find the power efficiency (minimum number of photons per bit) for each of these cases. It is shown that for high SNR the spectral efficiency is the same independent of the number of DOFs and that the half-Gaussian distribution is the optimum distribution. We are able to thus obtain a compact equation for spectral efficiency which behaves in a similar way to the Shannon capacity formula but with the SNR scaled by a constant.
We also show that for low SNR the half-Gaussian distribution is not the optimum distribution as the slope of the mutual information changes with the square of SNR which would lead to the number of photons per bit becoming infinite in the limit of SNR going to zero. We use a modified half-Gaussian distribution which has a discrete component (an impulse function at the origin) and provide a simple proof that this distribution results in a mutual information that goes to zero linearly with SNR resulting in a minimum number of photons per bit. Furthermore, by increasing the magnitude of the discrete component at the origin, it is shown that the minimum number of photons per bit for the incoherent channel approaches that of the coherent channel.Ph. D.
25
Papandreou, Panayiotis. "Design and prototype development of an optimum symmetrical number system direction finding array." Thesis, Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/8239.
Full textAbstract:
Approved for public release; distribution in unlimited.One method of estimating the direction of an electromagnetic source is based on phase comparison. In this thesis the design and fabrication of a prototype antenna to demonstrate a new DF antenna architecture is described. Four antenna elements are grouped into three pairs with element spacing according to a set of symmetrical number system pairwise relatively prime moduli (m1 = 3, m2 = 4, m3=5). The phase difference between each pair of elements is a symmetrical folding waveform that is determined using a mixer. The output voltage from each pair is amplitude analyzed using a small comparator ladder. In each channel, the symmetrically folding waveform, folds in accordance with the channel modulus and thus, only requires a precision according to that modulus. A high resolution DF is achieved after the N different SNS moduli are used and the results of these low-precision channels are recombined to yield the direction of arrival. The frequency of operation of the prototype is 8.5 GHz. Results based on measured and simulated data are resented
26
Yeleswarapu, Radhika M. "Scheduling Of 2-Operation Jobs On A Single Machine To Minimize The Number Of Tardy Jobs." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000216.
Full text
27
Lim, Michelle. "Optimum number of wind turbines customer-side in the state of Kansas using HOMER." Thesis, Wichita State University, 2009. http://hdl.handle.net/10057/2497.
Full textAbstract:
This research primarily is in finding the optimum number of wind turbines in the state of
Kansas customer-side. Three different areas, with different annual average wind speeds in
Kansas were studied: South Kansas, Wichita and Topeka, with decreasing annual wind speeds
respectively. Various other factors such as different customer load demands, implementation of
carbon taxes and a range of power prices were part of the study. Research was simulated using
HOMER program, which was developed by the National Renewable Energy Laboratory. It was
found that not only an increase in wind speed but size of load will increase the optimum number
of wind turbines. The addition of carbon taxes prove very useful in determining the economic
viability of having wind turbines in an optimal power system. A small study on the addition of
battery storage in a wind system was confirmed to have no substantial effect on it.
This thesis ultimately provides concrete values on the economic viability of having wind
turbines in small energy systems.Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science
28
Alali, Ammar Mohammed. "Novel approach towards 1D resistivity inversion using the systematically-determined optimum number of layers." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117908.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 102-109).
Determining the correct number of layers as input for ID resistivity inversion is important for constructing a model that represents the subsurface accurately. Current common methods to select the number of layers are performed in one of three ways: by trial-and-error and choosing the best model data-fit, by using the modified F-test, or through trans-dimensional model parameterization. Although these methods are creative approaches, they are computationally expensive, as well as time-consuming and painstaking in practice. In this thesis, I provide a method that solves the problem of choosing the correct number of layers represented by the apparent resistivity curve. The method follows the two-steps approach suggested by Simms and Morgan (1992) to systematically resolve the optimum number of layers. The first step is to run a fixed thickness inversion using a large number of layers in which the number of layers and layer thicknesses are fixed, and resistivity values are inversion parameters. I then integrate the outcome of the first inversion (the resistivity model) to determine the optimum number of layers based on changes of the slope. The detected number of layers is used as an input parameter for the second step; which is running a variable-thickness inversion (layer thicknesses and resistivities are both inversion parameters) for the outcome, the final resistivity model. Each step uses the Ridge Trace damped least-square inversion. The two inversion steps are integrated into a software program that performs the steps sequentially. The software determines all inversion parameters from the data file in a self-consistent manner. This proposed method uses a robust ridge trace regression algorithm, which has proven to be stable, accurate, and at least a hundred times faster than current methods.
by Ammar Mohammed Alali.
S.M.
29
Ahmed, Ibrahim H. I. "Mathematical modeling of an epidemic under vaccination in two interacting populations." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8857_1360922452.
Full textAbstract:
In this dissertation we present the quantitative response of an epidemic of the so-called SIR-type, in a population consisting of a local component and a migrant component. Each component can be divided into three classes, the susceptible individuals, usually denoted by S, who are uninfected but may contract the disease, infected individuals (I) who are infected and can spread the disease to the susceptible individuals and the class (R) of recovered individuals. If a susceptible individual becomes infected, it moves into the infected class. An infected individual, at recovery, moves to the class R. Firstly we develop a model describing two interacting populations with vaccination. Assuming the vaccination rate in both groups or components are constant, we calculate a threshold parameter and we call it a vaccination reproductive number. This invariant determines whether the disease will die out or becomes endemic on the (in particular, local) population. Then we present the stability analysis of equilibrium points and the effect of vaccination. Our primary finding is that the behaviour of the disease free equilibrium depend on the vaccination rates of the combined population. We show that the disease free equilibrium is locally asymptotically stable if the vaccination reproductive number is less than one. Also our stability analysis show that the global stability of the disease free equilibrium depends on the basic reproduction number, not the vaccination reproductive number. If the vaccination reproductive number is greater than one, then the disease free equilibrium is unstable and there exists three endemic equilibrium points in our model. Two of these three endemic equilibria are so-called boundary equilibrium points, which means that the infection is only in one group of the population. The third one which we focus on is the general endemic point for the whole system. We derive a threshold condition that determines whether the endemic equilibria is locally asymptotically stable or not. Secondly, by assuming that the rate of vaccination in the migrant population is constant, we apply optimal control theory to find an optimal vaccination strategy in the local population. Our numerical simulation shows the effectiveness of the control strategy. This model is suitable for modeling the real life situation to control many communicable diseases. Models similar to the model used in the main contribution of our dissertation do exist in the literature. In fact, our model can be regarded as being in-between those of [Jia et al., Theoretical Population Biology 73 (2008) 437-448] and [Piccolo and Billings, Mathematical and Computer Modeling 42 (2005) 291-299]. Nevertheless our stability analysis is original, and furthermore we perform an optimal control study whereas the two cited papers do not. The essence of chapter 5 and 6 of this dissertation is being prepared for publication.
30
El, Alaoui-Faris Yacine. "Modélisation et contrôle optimal de micro-nageurs magnétiques." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4094.
Full textAbstract:
Les micro-nageurs robotiques permettent d'effectuer des opérations à petite échelle telles que l'administration ciblée de médicaments et la chirurgie peu invasive. En raison de la difficulté de miniaturiser des sources d'énergie internes, les méthodes d'actionnement externes sont préférables aux sources intégrées, une stratégie populaire étant l'aimantation du nageur ou d'une de ses parties et son actionnement avec des champs magnétiques externes. L'étude qui suit se concentre sur les micro-nageurs magnétiques flexibles qui imitent les cellules flagellées commeles spermatozoïdes dans leur conception et leur mode de locomotion. Le but decette thèse est d'appliquer des outils numériques de modélisation et de contrôle optimal aux nageurs expérimentaux de l'Institut des Systèmes Intelligents et de Robotique (ISIR) afin d’améliorer leur contrôle et de fournir une méthode numérique pour la conception de commandes pour les micro-nageurs flexibles. La première étape de cette thèse a été le développement d'un modèle dynamique simplifié d'un nageur magnétique flexible en trois dimensions, basé sur une approximation des forces hydrodynamiques et sur la discrétisation de la courbure et de l'élasticité du flagelle. Une identification des paramètres hydrodynamiques et élastiques du modèle permet d'avoir un nageur simulé qui présente les mêmes caractéristiques de propulsion (notamment la réponse fréquentielle du nageur) que celles mesurées expérimentalement. La seconde étape a été d'utiliser le modèle développé pour la résolution numérique du problème de contrôle optimal consistant à de trouver le champ magnétique qui maximise la vitesse de propulsion du nageur sous des contraintes sur la commande reflétant les contraintes physiquement imposées au champ magnétique. La dernière étape a été l'implémentation des champ magnétiques calculés dans le dispositif expérimental de l'ISIR et l'étude de leur performances expérimentales ainsi que de la capacité du modèle à prédire la trajectoire du nageurRobotic micro-swimmers are able to perform small-scale operations such astargeted drug delivery, and minimally invasive medical diagnosis and surgery.However, efficient actuation of these robots becomes more challenging as their size decreases. Hence, wireless actuation is preferable over built-in actuation sources, one of the most popular strategies is the magnetization of parts of the swimmer and its actuation with an external magnetic field. In this thesis, we focus on flexible magnetic micro-swimmers that are similar to spermatozoa in their design and flagellar propulsion. Our goal is to use numerical modeling and optimal control tools to improve the performance of existing swimmers made at the ISIR laboratory (Institut des Systèmes Intelligents et de Robotique) and to propose a numerical control design method for experimental flexible micro-swimmers.Firstly, a simplified 3D dynamic model of a flexible swimmer has been developed, based on the approximation of hydrodynamic forces and the discretization of the curvature and elasticity of the tail of the swimmer. By fitting the hydrodynamic and elastic parameters of our model accordingly, we are able to obtain propulsion characteristics (mainly the frequency response of the swimmer) close to those experimentally measured. Secondly, we numerically solve the optimal control problem of finding the actuating magnetic fields that maximize the propulsion speed of the experimental swimmer under constraints on the control that reflect the constraints physically imposed on the magnetic field. The optimal magnetic fields found via numerical optimization are then implemented in the ISIR experimental setup in order to benchmark the experimental performance of the computed controls and the ability of the model to predict the trajectories of the experimental swimmer
31
Hooper, David A. "The basic underwater demolition/SEAL accession model determining the optimal number of junior officer accessions to meet end-strength goals." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5760.
Full textAbstract:
Approved for public release; distribution is unlimited.The mission of the Naval Special (NSW) community is to provide a versatile, responsive, and offensively focused force with continuous overseas presence in order to have strategic impact in missions that include special reconnaissance, direct action, unconventional warfare, and combating terrorism. Currently, the NSW community has large manpower gaps within the officer corps especially, at the Lieutenant Commander rank. This gap threatens the operational readiness of the NSW community, which in turn affects our national security. This thesis presents the development of the Basic Underwater Demolition/SEAL (BUD/S) Accession Calculator (BAC) which uses goal programming and Markov chain analysis to determine the optimal number of new accessions needed to enter the BUD/S training program to meet target end-strength goals for company grade ranks. By properly manning the junior ranks the Lieutenant Commander rank can be properly manned. The results demonstrate that the NSW community can closely meet target end-strength goals of 127 and 285 for Lieutenant Junior Grades and Lieutenants, respectively, with the 100 accessions to BUD/S every year. However, as the attrition rate fluctuates the number of accessions change. The most dramatic impact to BUD/S accession requirements is observed when attrition rate increases. Decrease in attrition rate show that small changes to accession requirements occur.
32
Chen, Xu. "New formulation of optical flow for turbulence estimation." Thesis, Ecully, Ecole centrale de Lyon, 2015. http://www.theses.fr/2015ECDL0025/document.
Full textAbstract:
Le flot optique est un outil, prometteur et puissant, pour estimer le mouvement des objets de différentes natures, solides ou fluides. Il permet d’extraire les champs de vitesse à partir d’une séquence d’images. Dans cette étude, nous développons la méthode du flot optique pour récupérer, d’une manière précise, le champ de vitesse des mouvements turbulents incompressibles. L’estimation de turbulence consiste à minimiser une fonction d’énergie composée par un terme d’observation et un terme de régularisation. L’équation de transport d’un scalaire passif est alors employée pour représenter le terme d’observation. Cependant, dans le cas où le nombre de Reynolds est grand, et, à cause des contraintes optiques, l’image n’est pas pleinement résolue pour prendre en compte la physique de toutes les échelles de la turbulence. Pour compléter les informations manquantes liées aux physiques des petites échelles, nous adoptons une démarche similaire à celle de Large Eddy Simulation (LES), et, proposons d’utiliser le modèle mixte afin de tenir compte de l’interaction entre les grandes échelles et celles non-résolues. Quant au terme de régularisation, il se repose sur l’équation de continuité des fluides incompressibles. Les tests à l’aide des images synthétiques et expérimentales de la turbulence bi-dimensionnelle - des données des cas test de la communauté du flot optique -, ont non seulement validé notre démarche, mais montrent une amélioration significative des qualités des champs de vitesses extraites. Le cas du flot optique, en 3D, relève encore du défi dans le cas de l’estimation des champs de vitesse de la turbulence. D’une part, contrairement au 2D où il existe des cas tests bien établis, il n’existe pas, à notre connaissance, des séquences d’images 3D référentielles permettant de tester notre démarche et méthode. D’autre part, l’augmentation du coût d’estimation demande des algorithme adaptés. Ainsi, nous sommes amené à utiliser la simulation numérique directe d’écoulement turbulent en présence d’un scalaire passif, pour générer des données de scalaires afin d’évaluer la performance du flot optique. Nous prêtons également attention à l’effet du nombre de Schmidt qui caractérise la relation entre la diffusion moléculaire scalaire et la dissipation de turbulence. Les tests sont ensuite effectués avec cette base de données numériques. Les résultats montrent que la précision de l’estimation augmente avec des nombres de Schmidt plus élevés. Par ailleurs, l’influence du terme de régularisation est aussi étudié au travers deux équations qui se différencient par l’ordre spatial des dérivées partielles. Les résultats numériques montrent que l’équation avec un terme de régularisation de seconde-ordre est meilleure que celle de premier-ordreThe method of optical flow is a powerful tool for motion estimation. It is able to extract the dense velocity field from image sequence. In this study, we employ this method to retrieve precisely the incompressible turbulent motions. For 2D turbulence estimation, it consists in minimizing an objective function constituted by an observation term and a regularization one. The observation term is based on the transport equation of a passive scalar field. For non-fully resolved scalar images, we propose to use the mixed model in large eddy simulation (LES) to determine the interaction between large-scale motions and the unresolved ones. The regularization term is based on the continuity equation of 2D incompressible flows. Evaluation of the proposed formulation is done over synthetic and experimental images. In addition, we extend optical flow to three dimensional and multiple scalar databases are generated with direct numerical simulation (DNS) in order to evaluate the performance of optical flow in the 3D context. We propose two formulations differing by the order of the regularizer. Numerical results show that the formulation with second-order regularizer outperforms its first-order counterpart. We also draw special attention to the effect of Schmidt number, which characterizes the ratio between the molecular diffusion of the scalar and the dissipation of the turbulence. Results show that the precision of the estimation increases as the Schmidt number increases. Overall, optical flow has showcased its capability of reconstructing the turbulent flow with excellent accuracy. This method has all the potential and attributes to become an effective flow measurement approach in fluid mechanics community
33
Venter, Johann Christiaan. "The optimal hydraulic diameter of semicircular and triangular shaped channels for compact heat exchangers / J.C. Venter." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4629.
Full textAbstract:
All heat pump cycles have one common feature that connects them to one another;
this feature is the presence of a heat exchanger. There are even some heat–driven
cycles that are completely composed of heat exchangers, every heat exchanger
fulfilling a different, though critical role.
The need therefore exists to optimize heat exchangers, more specifically Compact
Heat Exchangers (CHE). This study deals with the optimization of such a CHE by
determining an optimal hydraulic diameter of the micro–channels in a CHE, for
minimal hydraulic losses. Two Computational Fluid Dynamics (CFD) models were
developed for a single micro–channel that is present in a CHE. The first model had a
semi–circular cross–section, the second a triangular cross–section.
The results were verified by comparing it with existing experimental data. Following
the verification of the results, the micro–channel was optimized by implementing an
optimum diameter for the lowest pressure drop over the micro–channel. This was done
for both the semi–circular and triangular micro–channel cross–sections.Thesis (M.Ing. (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2011.
34
Telha, Cornejo Claudio (Claudio A. ). "Algorithms and hardness results for the jump number problem, the joint replenishment problem, and the optimal clustering of frequency-constrained maintenance jobs." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70446.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 107-110).
In the first part of this thesis we present a new, geometric interpretation of the jump number problem on 2-dimensional 2-colorable (2D2C) partial order. We show that the jump number of a 2D2C poset is equivalent to the maximum cardinality of an independent set in a properly defined collection of rectangles in the plane. We then model the geometric problem as a linear program. Even though the underlying polytope may not be integral, we show that one can always find an integral optimal solution. Inspired by this result and by previous work of A. Frank, T. Jordan and L. Vegh [13, 14, 15] on set-pairs, we derive an efficient combinatorial algorithm to find the maximum independent set and its dual, the minimum hitting set, in polynomial time. The combinatorial algorithm solves the jump number problem on convex posets (a subclass of 2D2C posets) significantly faster than current methods. If n is the number of nodes in the partial order, our algorithm runs in 0((n log n)2.5) time, while previous algorithms ran in at least 0(n9 ) time. In the second part, we present a novel connection between certain sequencing problems that involve the coordination of activities and the problem of factorizing integer numbers. We use this connection to derive hardness results for three different problems: -- The Joint Replenishment Problem with General Integer Policies. -- The Joint Replenishment Problem with Correction Factor. -- The Problem of Optimal Clustering of Frequency-Constrained Maintenance Jobs. Our hardness results do not follow from a standard type of reduction (e.g., we do not prove NP-hardness), and imply that no polynomial-time algorithm exists for the problems above, unless Integer Factorization is solvable in polynomial time..
by Claudio Telha Cornejo.
Ph.D.
35
RANJAN, ASHISH. "APPLICATION OF OPTIMIZATION TECHNIQUE IN FINDING LOCATION OF SWITCH & IT’S OPTIMAL NUMBERS IN DISTRIBUTION NETWORK." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14986.
Full textAbstract:
Reliability worth assessment is currently receiving considerable attention as it provides the opportunity to incorporate the costs or losses incurred by utility customers as a result of power failures in the overall analysis of system costs and benefits. A variety of approaches have been utilized to assess the cost of power interruptions. These include analytical methods, case studies and customer survey approaches. The survey approach can easily include the effect of many factors such as time of occurrence, duration and frequency of interruption and therefore provides a practical framework for detailed analysis. In recent years, power demand has increased with high information-oriented society. Since electric power systems play a major role in a modern society, professional engineers are responsible for the planning, design, and operation of power systems. A modern power system are desired to have high efficiency and high reliability. In this situation, new generation facilities and expansion of the transmission lines must be planed and constructed maintaining reliability of power systems and reducing loss of load in faults. However modern power systems are complex, highly integrated, and very large. It is difficult to determine the optimal set up point for that reason. Power system planning has been studied over decades. By formulation an optimization problem which has non-linearity with integer and continuous variables. The objective of this problem is maintenance of reliability and reducing loss of load. The exact optimal solution of this problem can be obtained by complete enumeration. However this method cannot be applied to realistic optimization problem due to its computation intensity.
36
Huang, Yu-Jie, and 黃郁傑. "Optimal number of suppliers and order allocation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/12126912922432484465.
Full text
37
Li, Min-Yu, and 李旻諭. "The optimal number of biotechnology stocks'' portfolio." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/67770153420625327407.
Full textAbstract:
碩士國立中正大學
企業管理所
97
Nowadays biotechnology is not only a burgeoning industry but also a newest target of investors in the universe. Four reasons could support why this thesis would choose biotech as a research topic. First, more and more people tend to rely on biotechnology for extending life expectancy or maintaining youth. Second, owing to the government’s investment policies, the potential of the biotechnology industry in Taiwan has greatly improved. Thirdly, many studies have shown that biotechnology stocks can resist economic downturns. The last reason is that there lacks a unified conclusion as to the optimal number of stocks in a portfolio that can fully diversify away the unsystematic risk. In this study, we use in our sample the data of Taiwan’s biotechnology stocks for the period of 2003 to 2008 to randomly construct various stock portfolios. We find portfolios of biotechnology stocks possess diversification effect and the optimal number is 63 in multiple regression analysis.
38
Chen, Qing-Shui, and 陳清水. "Optimal Number of Centers for Multicenter Clinical Trials." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/38058305974666111893.
Full text
39
Tsai, Tsung-Yu, and 蔡宗育. "GETTING AN OPTIMAL CONNECTION NUMBER OF A WEB SERVER." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/12911200948093575129.
Full textAbstract:
碩士大同大學
通訊工程研究所
98
Recently, the concept of energy efficiency and carbon reduction progressively gets more attention. And the energy inefficiency problem of computer room is an important issue. For this reason, this paper provides a framework design to get the optimal connection number of a web server. This includes getting the relation between CPU utilization and current, the relation between connection number and CPU utilization, and the relation between connection number and response time. And using ApacheBench and optimal connection number analysis derives from this paper to get the optimal connection number of a web server in deferent hardware equipment or system architecture. The optimal connection number as the condition for turn on physical machine or virtual machine. Eventually finds the balance between energy efficiency and availability. Otherwise, this paper also provides Scheduled Cooling Power Usage Effectiveness (SCPUE). And according to the experiment result and forecasting models to get the math model of air-conditioner current in computer room. In the future, we can use the model to control the air-conditioner current to increase the energy efficiency of computer room.
40
"Why information technology hasn't increased the optimal number of suppliers." Alfred P. Sloan School of Management, Massachusetts Institute of Technology, 1992, 2003. http://hdl.handle.net/1721.1/2436.
Full text
41
Han, Tien Der, and 韓天德. "Optimal Number of Firms to Collude in a Cournot Market." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/76475470552053094542.
Full textAbstract:
碩士佛光人文社會學院
經濟學系
94
This paper is based on linear demand and traditional Cournot model. There are n identical firms in a market producing homogenous goods. The results of this paper show that no matter what the size of a market is, a cartel will collude with all firms in a market to make the highest profits when there is no sanction. When the externality of collusion is viewed as sanction and imposed on a cartel, the cartel will take profits and social welfare into consideration simultaneously. Thus a cartel will collude with 34% of firms instead of all firms in the market to not only make the highest profits but also create the highest social welfare. That is, the externality of collusion is internalized by the sanction. Therefore, if a cartel is formed, then the cartel is efficient, while a cartel will not be formed if it is inefficient. If a cartel is efficient, the market share of it must be small. However, the required market share of a cartel has to be large enougha cartel to with small market share can not make its member firms more profitable than how they are when they do not participate in the cartel. Without higher profits, firms are lack of incentives to collude. Thus an efficient cartel will not necessarily be formed. Therefore,That is also the reason why no cartel in our model will be formed in every size of the market even though the cartel itself is profitable and socially desired after the sanction is imposed. Moreover, the size of a market is also crucial to collusion because the bigger a market is, the larger the required market share of a cartel has to be. Therefore, the bigger the market is, the harder the cartel is formed.
42
LUO, KUN-RONG, and 羅坤榮. "The optimal channel number design of the ring packet switch." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/59845559277724290896.
Full text
43
Chiang, Yi-Yen, and 江怡燕. "the optimal number of stock holding in Domestic equity fund." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/12376281414661421778.
Full textAbstract:
碩士國立中正大學
財務金融所
98
With financial liberalization and internationalization of the pace and the face of an increasing number of financial investment products, coupled with rapid growth of mutual funds, so that people invest in mutual funds has become a trend. A typical fund in the portfolio will contain many file shares, an increase in the number of shares held will bring the benefits of risk diversification, but the increase in the number of portfolio diversification over the issue too much Yekuaidaozhi offset by the interests of risk diversification, resulting monitoring costs, transaction costs and human costs of such over-diversification problems affecting the performance of the Fund. Therefore, the size of the portfolio can not be spread too thin nor too concentrated, the study of the domestic equity fund "optimal" hold Chunghwa Express Corp how many can we really reduce the risk of the portfolio, and multiple regression is used to obtain first-order differential performance maximization of the number of shares held. Empirical results indicate that the domestic stock index for the contingency fund to Sharp, the optimal number of shares held by Chunghwa Express Corp 43 to Jensen index number for the strain under the 46 stocks in order to target the strain Enoch Choi number of shares under the 38 ; Global Equity Fund Sharpe Ratio as dependent variables, the optimal stock holding Chunghwa Express Corp 26 to Jensen index number for the strain under the 30 stocks; inter-regional equity funds to Sharpe Ratio as dependent variables, the optimal holding Chunghwa Express Corp 40 stocks, with Johnson as the dependent variable index of 36 stocks lower; single country equity indices for the contingency fund to Sharp, the optimal number of shares held by Chunghwa Express Corp 48 to Jensen index number for the strain under 45 stocks. Generally speaking, the optimal single country equity funds hold shares up, come back to the domestic equity fund was the second highest, followed by cross-regional model for the stock funds, and finally, the optimal global funds held by Chunghwa Express Corp at least. The optimal number of shares held between 30-48 between stocks, funds can be formed to maximize the performance of the optimal portfolio.
44
廖美珍. "Optimal Number of Brands for Heterogeneous Goods under Price Competition." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/41751971723124767544.
Full textAbstract:
碩士佛光大學
經濟學系
100
With demand for environment-friendly, healthy, and natural foods now a global trend, organic foods have become a booming industry. Currently, Europe has the best developed organic foods industry. Since 1986, Taiwan has undergone a developmental process of preparation, testing, demonstration, and promotion, with the result that there are now a large number of vendors producing and selling products to meet the homogenous market demand. For this reason, the market has now moved from its former monopoly market state to its current monopolistic competitive market state. To meet the general public’s rising qualities of life and heightening expectations for environment-friendly, healthy, and natural foods, suppliers have responded with a large variety of heterogeneous organic products. This happens to be a key characteristic of a monopolistic competition market. Using the organic foods industry as a starting point, this paper compares the pricing, output, store branch or brand numbers, and social welfare differences between monopoly markets (with multiple store branches or brands), monopolistic competitive markets (with multiple store branches or brands) that produce a single product, and perfectly competitive markets. The first stage of this paper uses the game theory to identify the optimal number of store branches (brand numbers), and the second stage to study price competition. To backward method for solving first obtained the second stage of price competition, and then investigate the optimal number of branches in the different market structures (brand numbers). Store branch numbers have a substitution indicator critical point that falls between 0 and 1. Although this critical point is not an exact value, we can make certain assumptions to determine store branch numbers under different market conditions. Results show that when a product has small levels of substitution, the numbers of store branches are greatest for perfectly competitive markets, and smallest for monopoly markets. Conversely, when a product’s substitution levels are high, the ranking of store branch numbers are (from great to small), monopoly markets, monopolistic competition markets, and perfectly competitive markets. If we step away from economic theories regarding product substitution and market types, and view these products as agricultural goods or necessities, there is empirical evidence that the results above apply under actual market conditions. Coincidentally, the results of this study mirror the efforts of a particular organic foods chain in Taiwan, which in its initial stage of operations played an approximate government role in that they paid subsidies or provided inputs or technologies to encourage farmers’ willingness to farm. Also, they used unique marketing channels to aid organic foods farmers in lowering disproportional profit gains. This was not only more efficient, but also boosted farmer confidence in the production of organic vegetables; thus were numerous obstacles overcome, and the doors to the Taiwanese organic foods market opened to provide a better way of life for the general public.
45
Hsieh, Meng-Ke, and 謝孟珂. "Methods of estimating the optimal number and locations of cutpoints." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/arje68.
Full textAbstract:
碩士國立中山大學
應用數學系研究所
105
In clinical,we often need to cut the continuous prognostic factor into categorical variables in order to determine the clinical diagnosis. Traditionally, there are many ways to find one cut point to divide data into two groups. This paper will provide a method, when you need more than one cut point, you can correctly determine the optimal numbers of cut points and their locations. By multivariate Cox proportional hazard model and genetic algorithm , using the log-likelihood statistic as the criterion to determine the optimal cut points, and two-fold cross validation to correct the p-value, AIC, and select the correct number of cut points. At last, we use cervical cancer data to discuss the different prognostic factors under the optimal number of points and their locations.
46
Hsu, Chun-Peng, and 許駿鵬. "The Optimal Number of Serve in Queuing Model With Loss Function." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/06358173388119996802.
Full textAbstract:
碩士輔仁大學
應用統計學研究所
94
This paper discuss the queuing model with bulk service inder counting proceses and use loss function to value the optimal number id services. The Queuing model is based on counting processes. Assume the distribution of customers arrive indepentlly but the interval arrival time is not identical, it means that the rate of arrival cahnge with time. We define the model is λ(t) = θλ0(t) and consider some situtations such as poisson processes, linear medol and quadratic function. About the parameter , θ, we will use the property of weak converge of martingale central limit theory to estimate it. Beside, we also consider the dormant of service. The aspect of loss function, the first loss made form the rounds of the machine working, second is customers’ waiting time and the third is the loss of machine built-on. We take an elevator system of a hospital for an example and estimate the parameter of the rate of customers arrive and elevators interval serve time. The part of customers’ arrival, the three situations are offpeak (ˆθ=0.1)、averge (ˆθ = 0.3) and peak-hour (ˆθ = 0.6); the capacity of elevator are hight capacity (m = 19)、normal capacity (m = 13) and low capacity (m = 8). About the efficiency of service of elevator, good efficiency (α=1.9,=60.3)、averge efficiency (α=2.3,β=80.3) and low efficiency (α=2.9,β=100.3) will be considered. In the hospital case, ˆθ = 0.3, ˆα = 2.3 and ˆ β = 80.3. If the offpeak (ˆθ = 0.1), the optimal number of service of poisson processes、linear model and qaudratic function is 2. If the customers arrival rate is average (ˆθ=0.3), the optimal number of service is 5、4 and 5. If the customers arrival rate is peak-hour (ˆθ=0.6), the optimal number of service is 9、6 and 9。Other conclusion of simulation will be displayed in Ch4.
47
Huang, Yi-Chin, and 黃怡靜. "Optimal Combination and Fleet Number of Vehicle Size for Bus Routes." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/08943270279463390386.
Full textAbstract:
碩士國立臺灣大學
土木工程學研究所
93
The bus system will hardly be substituted in any city, now or in the future. Hence, running buses more efficiently will be the main consideration of bus operators. Presently most bus operators use standard buses or use a singly type of bus to provide service. This leads some sections of the buses being overcrowded in peak periods and the load factor in the off-peak periods are low. Since using mixed types of buses were proposed in some previous researches, they only discussed a peak period of time or with many unsuitable assumptions. The optimal combination of minibuses and standard buses has never been investigated. Therefore, in this research, we focus on the optimal combination, the number of vehicles in the fleet and its schedule under a given level of service and the known trip distribution, to achieve the objective of minimizing total system costs. Furthermore, we will extend the analysis period to a whole day and then to a whole week to find out the optimal bus combination and its fleet number of vehicle size of a route.
48
Kuan, Chang-Hui, and 官長輝. "Genetic algorithm for the optimal number of freeway bus and scheduling." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/44323095519432016600.
Full textAbstract:
碩士輔仁大學
管理學研究所
91
The quality of freeway bus scheduling and optimal number of bus influences transportation company performance deeply. Cost of the duty over-cover or uncover piece-of-work and bus waiting for dispatching in the station are the most important subject that need to be solved. The optimal number bus is a medium-term decision. It limited the system capacity that can serve customers, should be solved with bus scheduling. The freeway bus scheduling is a problem of short-term decision, and problem solving itself has very big pressure of the time limited. When there is a bus that met the occasional accidents: such as traffic jam and car breakdown, it usually needed to be re-scheduled immediately. Bus scheduling is a complex NP-hard problem. In previous researches about freeway bus scheduling problem, the scholars use heuristic or optimal algorithm to find the best solution. However, the solution of the former algorithm can’t guarantee to give satisfaction, due to into confinement in a contain condition, while the latter’s processing time is too long. This problem will suffer from the scale limit as unable to consider too many practical terms, with the result that its amplification the value suffers a query. This study using genetic algorithm to solve the problem, takes number of bus and bus scheduling into consideration, it will produce solutions rapidly and make the approximate optimal solution in a short time. For checking the usefulness of the method, we use the bus timetable of the current transportation company to run tests. The results show that the various methods that this study suggests can resolve the freeway bus scheduling problems quickly and improve the performance of the freeway transportation company. They carried out a high improvement rate, about 22%.
49
Lo, Hsiao-Chun, and 羅曉君. "Determination of the Optimal Number of Suppliers Considering the Location Failures." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/45455618908116429079.
Full textAbstract:
碩士樹德科技大學
經營管理研究所
99
Supply risks increase if a corporate has fewer suppliers, while managerial cost increases with many suppliers. Therefore, it is critical for procurement managers to determine the optimal number of suppliers. This study mainly investigates the impact of supplier numbers on corporate purchasing. Prevails studies on the supply risk of supply disruption only into consideration the super event and unique event on supply failures. The supply risks in geographical regions, such as, the 911 event in USA and The 311 earthquake in Japan affects global supply chains, Therefore, the semi-super event should be taken into consideration. In addition, the calculation of the loss caused by supplier failures was too complicated, this study employ Taguchi loss function to simplify the loss calculation. The study provides a model for corporate practitioners to determine the optimal number of supplier by minimizing the total purchasing costs.
50
GAO, XU, and 高旭. "A study of optimal containershipize, speed and number of ships in fleet." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/64950268440485550088.
Full text