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Citation - WoS: 1
Citation - Scopus: 1
Effect of Estimation Under Nonnormality on the Phase Ii Performance of Linear Profile Monitoring Approaches
(Wiley, 2019) Aytacoglu, Burcu; Bayrak, Ozlem Turker
The number of studies about control charts proposed to monitor profiles, where the quality of a process/product is expressed as function of response and explanatory variable(s), has been increasing in recent years. However, most authors assume that the in-control parameter values are known in phase II analysis and the error terms are normally distributed. These assumptions are rarely satisfied in practice. In this study, the performance of EWMA-R, EWMA-3, and EWMA-3(d(2)) methods for monitoring simple linear profiles is examined via simulation where the in-control parameters are estimated and innovations have a Student's t distribution or gamma distribution. Instead of the average run length (ARL) and the standard deviation of run length, we used average and standard deviation of the ARL as performance measures in order to capture the sampling variation among different practitioners. It is seen that the estimation effect becomes more severe when the number of phase I profiles used in estimation decreases, as expected, and as the distribution deviates from normality to a greater extent. Besides, although the average ARL values get closer to the desired values as the amount of phase I data increases, their standard deviations remain far away from the acceptable level indicating a high practitioner-to-practitioner variability.
Citation - WoS: 6
Citation - Scopus: 4
Propagation of Cross Beams Through Atmospheric Turbulence
(Spie-int Soc Optical Engineering, 2005) Yenice, YE; Eyyuboglu, HT; Baykal, Y
Propagation properties of cross beam in turbulent medium are studied. A cross beam is constructed by the sum of two highly asymmetric Gaussian beams placed along transverse axes. It is known that such beams, when propagating in free space, will exhibit contrasting diffraction behaviours; they expand widely in one axis, while they are almost nondiffracting in the other axis within useful link lengths. This behaviour allows detecting the two components and a sum component if desired separately with a practical multiaperture receiver. Bearing in mind that this property can be exploited for a diversity scheme, our present work focuses on the propagation of such beams in turbulent atmosphere. To this end, starting with a source field expression of the cross beam, the second order mutual coherence function is formulated at the receiver plane. Intensity plots describing the dependence on the source and propagation parameters on the receiver plane are provided. The results tend to confirm the applicability of the concept provided the design parameters are appropriately chosen. For a decisive assessment, however, turbulence-induced beam wander must also be examined.
Finding the most suitable irrigation dams for hydropower development by using gis tools
(2020) Bayati, Omar Al
This thesis aims to find the most suitable irrigation dams for hydropower development in Turkey to provide clean energy from an available resource by assessing on technical, spatial, and environmental criteria. The selected dams are arranged based on their suitability scores into three categories (high, medium and low) using a multi-criteria fuzzy logic tool that calculates the score separately for each criterion and then aggregates them into an overall suitability score. Six criteria are assessed: normal water level, reservoir storage capacity, dam purpose, years in operation, nearest substation distance and environment impact assessment requirement. The criterion of nearest substation distance was used to ensure that the benefits of potential power are consistent with the cost of grid connection. A methodology for finding best grid connection path is presented based on a multi-criteria geographic information system (GIS) spatial analyst to achieve the least cost, lowest power losses and lowest environmental impact. Two dams are chosen as case studies, Karadere and Karaçomak. For these dams, technical and spatial criteria are evaluated and the potential power and economic benefits are estimated. A least cost path methodology is applied to find the best grid connection path for each of those dams to their nearest substations.
Hans-hermann Hoppe’nın Argümantasyon Etiği ve Özel Hukuk Toplumu
(2024) Didin, Emre
Önde gelen liberteryen teorisyenlerden biri olan Hans-Hermann Hoppe (1949-), liberteryen etiğin temellendirilmesine yönelik “argümantasyon etiği” ve “özel hukuk toplumu” kavramlarıyla tanınmaktadır. Bu çalışmada öncelikle argümantasyon etiğinin temel argümanları, temelleri ve hakkındaki eleştiriler irdelenmektedir. Daha sonra, Hoppe’nın özel hukuk toplumuna adalet ve düzen hizmetleri bağlamında odaklanılmaktadır. Bu bağlamda, ilk olarak, Hoppe’nın bir devletin kanun ve düzen tekelinin imkânsızlığı ve tercih edilmezliği üzerine argümanları sunulmaktadır. Ayrıca argümantasyon etiğine göre özel hukuk toplumu yegâne meşru sistemdir. İkinci olarak, Hoppe’nın, aşkın bir hukukun tamamen yokluğu olan, saf bir özel hukuk toplumunun, nasıl işleyeceğine dair fikirleri sunulmaktadır. Hoppe’ya göre, hiçbir devlete nesnel bir hukuk sistemini yeterince koruyacağı konusunda güvenilemezken, adalet ve düzenin özel polis, hukuk ve tahkim şirketleri tarafından sağlandığı bir özel hukuk toplumu bunu yapabilecektir. Hoppe’nın argümantasyon etiğine dayanan değerden azat yaklaşımı özel hukuk toplumu modeline de taşınmaktadır zira Hoppe, takipçisi olduğu Murray Rothbard’ın aksine hiçbir zaman bir “olması gereken” ifadesi öne sürmemekte veya doğal haklara ya da faydacılığa başvurma ihtiyacı duymamaktadır. Hoppe’nın katkılarının hem Misescı hem de Rothbardçı özel mülkiyet savunularını geliştirdiği ve Hoppe’nın özel hukuk toplumunun Rothbard’ın özel mülkiyet anarşisi fikrine katkı verdiği gözlenmiştir. Hoppecı argümantasyon etiği ve özel hukuk toplumu kavramlarını Türk literatüründe ilk kez inceleyen bu çalışma, liberteryen mülkiyet etiği ve Hans-Hermann Hoppe üzerine daha fazla analiz yapılmasının önünü açacaktır.
Broiler House Performance Analysis and Chick Entrance Planning for a Broiler Chicken Integration
(2012) Satır, Benhür; Yıldırım, Gonca; Kırca, Ömer
Increasing rates of chicken meat production has a substantial impact on the Turkish economy. Per capita production in Turkey is close to the average production of the top 20 countries in the world. The production is done by integrated organizations, incorporating an integrator chicken company affiliated with all aspects of the production in an organization. There are many complicated processes, stages and parties involved in a typical integration, bringing with them many interesting problems. In this paper, we focus on tactical and operational decisions required during the broiler growing stage, motivated by the requirements of a moderate-sized integrator in the Marmara Region of Turkey. We use analysis of variance to compare the performances of available broiler houses, and to find the factors effecting the performance measures. Then, we present a mixed-integer linear program which uses the results of our performance analysis to find the least costly set of broiler houses with which the integrator should work, and the chick entrance times into these houses over a planning period.