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61.
Ufuk Cebeci 《Expert systems with applications》2009,36(5):8900-8909
An enterprise resource planning system (ERP) is the information backbone of a company that integrates and automates all business operations. It is a critical issue to select the suitable ERP system which meets all the business strategies and the goals of the company. This study presents an approach to select a suitable ERP system for textile industry. Textile companies have some difficulties to implement ERP systems such as variant structure of products, production variety and unqualified human resources. At first, the vision and the strategies of the organization are checked by using balanced scorecard. According to the company’s vision, strategies and KPIs, we can prepare a request for proposal. Then ERP packages that do not meet the requirements of the company are eliminated. After strategic management phase, the proposed methodology gives advice before ERP selection. The criteria were determined and then compared according to their importance. The rest ERP system solutions were selected to evaluate. An external evaluation team consisting of ERP consultants was assigned to select one of these solutions according to the predetermined criteria. In this study, the fuzzy analytic hierarchy process, a fuzzy extension of the multi-criteria decision-making technique AHP, was used to compare these ERP system solutions. The methodology was applied for a textile manufacturing company. 相似文献
62.
Erol Egrioglu Cagdas Hakan Aladag Ufuk Yolcu Vedide R. Uslu Murat A. Basaran 《Expert systems with applications》2009,36(7):10589-10594
Fuzzy time series methods have been recently becoming very popular in forecasting. These methods can be categorized into two subclasses that are univariate and multivariate approaches. It is a known fact that real time series data can actually be affected by many factors. In this case, the using multivariate fuzzy time series forecasting model can be more reasonable in order to get more accurate forecasts. To obtain fuzzy forecasts when multivariate fuzzy time series approach is adopted, the most applied method is using tables of fuzzy relations. However, employing this method is a computationally though task. In this study, we introduce a new method that does not require using fuzzy logic relation tables in order to determine fuzzy relationships. Instead, a feed forward artificial neural network is employed to determine fuzzy relationships. The proposed method is applied to the time series data of the total number of annual car road accidents casualties in Belgium from 1974 to 2004 and a comparison is made between our proposed method and the methods proposed by Jilani and Burney [Jilani, T. A., & Burney, S. M. A. (2008). Multivariate stochastic fuzzy forecasting models. Expert Systems with Applications, 35, 691–700] and Lee et al. [Lee, L.-W., Wang, L.-H., Chen, S.-M., & Leu, Y.-H. (2006). Handling forecasting problems based on two factors high order fuzzy time series. IEEE Transactions on Fuzzy Systems, 14, 468–477]. 相似文献
63.
The goal of Ambient Assisted Living (AAL) research is to improve the quality of life of the elderly and handicapped people and help them maintain an independent lifestyle with the use of sensors, signal processing and telecommunications infrastructure. Unusual human activity detection such as fall detection has important applications. In this paper, a fall detection algorithm for a low cost AAL system using vibration and passive infrared (PIR) sensors is proposed. The single-tree complex wavelet transform (ST-CWT) is used for feature extraction from vibration sensor signal. The proposed feature extraction scheme is compared to discrete Fourier transform and mel-frequency cepstrum coefficients based feature extraction methods. Vibration signal features are classified into “fall” and “ordinary activity” classes using Euclidean distance, Mahalanobis distance, and support vector machine (SVM) classifiers, and they are compared to each other. The PIR sensor is used for the detection of a moving person in a region of interest. The proposed system works in real-time on a standard personal computer. 相似文献
64.
Michele De Bastiani Rawan Jalmood Jiang Liu Christina Ossig Aleš Vlk Karol Vegso Maxime Babics Furkan H. Isikgor Anand S. Selvin Randi Azmi Esma Ugur Swarnendu Banerjee Alessandro J. Mirabelli Erkan Aydin Thomas G. Allen Atteq Ur Rehman Emmanuel Van Kerschaver Peter Siffalovic Michael E. Stuckelberger Martin Ledinsky Stefaan De Wolf 《Advanced functional materials》2023,33(4):2205557
Textured silicon wafers used in silicon solar cell manufacturing offer superior light trapping, which is a critical enabler for high-performance photovoltaics. A similar optical benefit can be obtained in monolithic perovskite/silicon tandem solar cells, enhancing the current output of the silicon bottom cell. Yet, such complex silicon surfaces may affect the structural and optoelectronic properties of the overlying perovskite films. Here, through extensive characterization based on optical and microstructural spectroscopy, it is found that the main effect of such substrate morphology lies in an altering of the photoluminescence response of the perovskite, which is associated with thickness variations of the perovskite, rather than lattice strain or compositional changes. With this understanding, the design of high-performance perovskite/silicon tandems is rationalized, yielding certified power conversion efficiencies of >28%. 相似文献
65.
Forecast Combination by Using Artificial Neural Networks 总被引:3,自引:1,他引:2
One of the efficient ways for obtaining accurate forecasts is usage of forecast combination method. This approach consists
of combining different forecast values obtained from different forecasting models. Also artificial neural networks and fuzzy
time series approaches have proved their success in the field of forecasting. In this study, a new forecast combination approach
based on artificial neural networks is proposed. The forecasts obtain from different fuzzy time series models are combined
by utilizing artificial neural networks. The proposed method is applied to index of Istanbul stock exchange (IMKB) time series
and the results are compared to other forecast combination methods available in the literature. As a result of the implementation,
it is seen that the proposed forecast combination approach produces better forecasts than those produced by other methods. 相似文献
66.
Bakir Ufuk; Coutinho Pedro M.; Sullivan Patrick A.; Ford Clark; Reilly Peter J. 《Protein engineering, design & selection : PEDS》1993,6(8):939-946
Nine single amino add mutations in the active site of Aspergillusawamori glucoamylase were made by cassette mutagenesis to alterthe pH dependence of the enzyme and to determine possible functionsof the mutated residues. The Glul79-Asp mutation expressed inyeast led to a very large decrease in kcat but to no changein Km, verifying this residue's catalytic function. Aspl76-Gluand Glul80-Asp mutations affected Km a more than kcat, implyingthat Aspl76 and Glul80 are involved in substrate binding orstructural integrity. The Leul77-Asp mutation decreased kcatonly moderately, probably by changing the position of the generalacid catalytic group, and did not affect Km. The Trpl78-Aspmutation greatly decreased kcat while increasing Km, showingthe importance of Trpl78 in the active site. Vall81-Asp andAsnl82-Asp mutations changed kinetk values little, suggestingthat Vall81 and Asnl82 are of minor catalytic and structuralimportance. Finally, insertions of Asp or Gly between residues176 and 177 resulted in almost complete loss of activity, probablycaused by destruction of the active site structure. No largechanges in pH dependence occurred in those mutations where kineticvalues could be determined, in spite of the increase in mostcases of the total negative charge. Increases in activationenergy of maltoheptaose hydrolysis in most of the mutant glucoamylasessuggested cleavage of individual hydrogen bonds in enzyme-substratecomplexes. 相似文献
67.
68.
Zinc and copper contents in the edible parts (muscle, fillet) of 49 commercially used fish species from the eastern Mediterranean Sea (Izmir Outer Bay, Homa Lagoon/Izmir and Mersin Bay) were determined by differential pulse stripping anodic voltammetry. In the sample preparation step, all frozen fish samples were lyophilized, milled in a ball mill and finally decomposed in an oxygen plasma ashing chamber. Among the three sampling locations, the highest zinc concentration was found in Mediterranean shad (Alosa fallax nilotica) from Izmir Outer Bay with 9.73 mg/kg wet weight and the highest copper content was found in derbio (Trachinotus ovatus) from Homa Lagoon with 1.14 mg/kg wet weight. The accuracy of the concentrations determined in this study was checked by the measurements of certified reference material no. 422 cod muscle from the Commission of the European Communities, Community Bureau of Reference. All zinc and copper concentrations observed in species of the eastern Mediterranean Sea showed that fish from this area are good sources of these essential elements. 相似文献
69.
Emrah Sagir Siamak Alipour Kamal Elkahlout Harun Koku Ufuk Gunduz Inci Eroglu Meral Yucel 《International Journal of Hydrogen Energy》2017,42(36):22743-22755
Photofermentative hydrogen production by immobilized Rhodobacter capsulatus YO3 was carried out in a novel photobioreactor in sequential batch mode under indoor and outdoor conditions. Long-term H2 production was realized in a 1.4 L photobioreactor for 64 days using Rhodobacter capsulatus YO3 immobilized with 4% (w/v) agar on 5 mM sucrose and 4 mM glutamate. The highest hydrogen yield (19 mol H2/mol sucrose) and hydrogen productivity (0.73 mmol H2 L?1 h?1) were achieved indoors on 5 mM sucrose. The effect of initial sucrose concentration (5 mM, 10 mM, and 20 mM) on hydrogen production was also investigated. Sustained hydrogen production was carried out under natural, outdoor conditions as well. For the outdoor experiments, the highest hydrogen productivity and yield were obtained as 0.87 ± 0.06 mmol H2 L?1 h?1 and 6.1 ± 0.2 mol H2/mol sucrose, respectively on 10 mM sucrose. Furthermore, this system prevented sudden pH drops and fluctuations caused by the utilization of sucrose throughout the process. These results demonstrate that a proper immobilization setup can lead to long-term efficient and robust hydrogen production even under naturally varying conditions. 相似文献
70.
Abdulkadhim Fahad Ghalib Yi Zhang Onaizah Ameer N. Rabee Furkan Al-Muqarm Abbas Mohammed Ali 《Wireless Personal Communications》2022,124(1):815-838
Wireless Personal Communications - RTS/ CTS protocol serves multihop wireless networks poorly due to its single-hop design. TDMA protocol surpasses RTS/ CTS but unable to solve the dynamic needs of... 相似文献