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Genc R.,German-Turkish University
Procedia Manufacturing | Year: 2017

Communication entails the transfer of ideas, thoughts or feelings by the sender to receiver via verbal or nonverbal means. This transfer gains special significance in business especially in the service sector since the service providers work with humans based on communication. In any sustainable plan or strategy communication plays a vital role. In order to plan and develop sustainability and sustainable strategies it is neccessary for people to express themselves internally and externally by using appropriate mode(s) of communications. Thus, in order to establish effective communication, the managers in an organization has to channel the receiver what they mean to communicate in a simple, direct and precise manner whether it be on the oral or written modality. To achieve this end, they should also take into consideration the gender and cultural variations in terms of communication. © 2017 The Authors


Onhon N.O.,German-Turkish University | Cetin M.,Istanbul Science University
Eurasip Journal on Advances in Signal Processing | Year: 2017

Synthetic aperture radar (SAR) returns from a scene with motion can be viewed as data from a stationary scene, but with phase errors due to motion. Based on this perspective, we formulate the problem of SAR imaging of motion-containing scenes as one of joint imaging and phase error compensation. The proposed method is based on the minimization of a cost function which involves sparsity-imposing regularization terms on the reflectivity field to be imaged, considering that it admits a sparse representation as well as on the spatial structure of the motion-related phase errors, reflecting the assumption that only a small percentage of the entire scene contains moving objects. To incorporate the spatial structure of the phase errors into the problem, we provide three different sparsity-enforcing prior terms. In order to achieve computational gains, we also present a two-step version of our approach, which first determines regions of interest that are likely to contain the moving objects and then applies our sparsity-driven approach for joint image reconstruction and autofocusing in such a spatially constrained setting. Our preliminary experiments demonstrate the effectiveness of this new moving target SAR imaging approach. © 2017, The Author(s).


Gencay E.,German-Turkish University | Schuller P.,Marmara University | Erdem E.,Sabanci University
Journal of Intelligent Manufacturing | Year: 2017

In automotive industry, validation and maintenance of product configuration data is a complex task. Both orders from the customers and new product line designs from the R&D department are subject to a set of configuration rules to be satisfied. In this work, non-monotonic computational logic, answer set programming in particular, is applied to industrial-scale automotive product configuration problems. This methodology provides basic validation of the product configuration documentation and validation of single product orders, where Reiter style diagnosis provides minimal changes needed to correct an invalid order or a product configuration rule set. In addition, a method for discovering groups of product configuration variables that are strongly related can be obtained by small modification of the basic logic program, and by the usage of cautious and brave reasoning methods. As a result, options that are used in every, or respectively in no configuration, can easily be identified, as well as groups of options that are always used together or not at all. Finally it is possible to single out mandatory and obsolete options, relative to a preselected set of included or excluded options. Experimental results on an industrial dataset show applicability, example results, and computational feasibility with computation times on the order of seconds using a state-of-the-art answer set solver on standard PC hardware. © 2017 Springer Science+Business Media New York


Dilman I.,Technical University of Istanbul | Yildirim U.,Technical University of Istanbul | Yildirim U.,German-Turkish University | Cosgun S.,Technical University of Istanbul | And 3 more authors.
2016 IEEE Asia-Pacific Conference on Applied Electromagnetics, APACE 2016 | Year: 2017

This paper investigates feasibility of detection of blooded area in a realistic head phantom with microwave imaging. Realistic phantom is illuminated by 36 line sources and the scattering field data is calculated numerically with method of moments. Additive white Gaussian noise with 20 dB is added for more realistic scenario. Contrast Source Inversion method is used to reconstruct the blooded area. Simulations are done at different operating frequencies of 500 MHz, 800 MHz and 1000 MHz. Moreover, results either with electrically different background mediums or free space are discussed in this study. The numerical results show that it is possible to determine the square shape blooded area with size about 2.6cm × 2.6cm between the 800-1000Mhz frequency range in the dielectric matching medium. © 2016 IEEE.


Cetin M.,Sabanci University | Stojanovic I.,Nokia Inc. | Onhon O.,German-Turkish University | Varshney K.,IBM | And 3 more authors.
IEEE Signal Processing Magazine | Year: 2014

This article presents a survey of recent research on sparsity-driven synthetic aperture radar (SAR) imaging. In particular, it reviews 1) the analysis and synthesis-based sparse signal representation formulations for SAR image formation together with the associated imaging results, 2) sparsity-based methods for wide-angle SAR imaging and anisotropy characterization, 3) sparsity-based methods for joint imaging and autofocusing from data with phase errors, 4) techniques for exploiting sparsity for SAR imaging of scenes containing moving objects, and 5) recent work on compressed sensing (CS)-based analysis and design of SAR sensing missions. © 2014 IEEE.


Gok M.,Yalova University | Herand D.,German-Turkish University
MATEC Web of Conferences | Year: 2016

Prediction of bacterial virulent proteins is critical for vaccine development and understanding of virulence mechanisms in pathogens. For this purpose, a number of feature encoding methods based on sequences and evolutionary information of a given protein have been proposed and applied with some classifier algorithms so far. In this paper, we performed composition moment vector (CMV), which includes information about both composition and position of amino acid in the protein sequence to predict bacterial virulent proteins. The tests were validated in three different independent datasets. Experimental results show that CMV feature encoding method leads to better classification performance in terms of accuracy, sensitivity, f-measure and the Matthews correlation coefficient (MCC) scores on diverse classifiers. © Owned by the authors, published by EDP Sciences 2016.


Unal C.M.,German-Turkish University | Unal C.M.,TU Braunschweig | Steinert M.,TU Braunschweig | Steinert M.,Helmholtz Center for Infection Research
Biochimica et Biophysica Acta - General Subjects | Year: 2015

Background FK506-binding proteins (FKBPs) contain a domain with peptidyl-prolyl-cis/trans-isomerase (PPIase) activity and bind the immunosuppressive drugs FK506 and rapamycin. FKBPs belong to the immunophilin family and are found in eukaryotes and bacteria. Scope of review In this review we describe two major groups of bacterial virulence-associated FKBPs, the trigger factor and Mip-like PPIases. Moreover, we discuss the contribution of host FKBPs in bacterial infection processes. Major conclusions Since PPIases are regarded as alternative antiinfective drug targets we highlight current research strategies utilizing pipecolinic acid and cycloheximide derivatives as well as substrate based inhibitors. General significance The current research strategies suggest a beneficial synergism of drug development and basic research. This article is part of a Special Issue entitled Proline-directed Foldases: Cell Signaling Catalysts and Drug Targets. © 2014 Elsevier B.V. All rights reserved.


Xiong Q.,University of Cologne | Unal C.,TU Braunschweig | Unal C.,German-Turkish University | Matthias J.,University of Cologne | And 3 more authors.
Open Biology | Year: 2015

Macroautophagy is a highly conserved intracellular bulk degradation system of all eukaryotic cells. It is governed by a large number of autophagy proteins (ATGs) and is crucial for many cellular processes. Here, we describe the phenotypes of Dictyostelium discoideum ATG16- and ATG9-/16- cells and compare them to the previously reported ATG9- mutant. ATG16 deficiency caused an increase in the expression of several core autophagy genes, among thematg9 and the two atg8 paralogues. The single and double ATG9 and ATG16 knock-out mutants had complex phenotypes and displayed severe and comparable defects in pinocytosis and phagocytosis. Uptake of Legionella pneumophila was reduced. In addition, ATG9- and ATG16- cells had dramatic defects in autophagy, development and proteasomal activity which were much more severe in the ATG9-/16- double mutant. Mutant cells showed an increase in poly-ubiquitinated proteins and contained large ubiquitinpositive protein aggregates which partially co-localized with ATG16-GFP in ATG9-/16- cells. The more severe autophagic, developmental and proteasomal phenotypes of ATG9-/16- cells imply that ATG9 and ATG16 probably function in parallel in autophagy and have in addition autophagy-independent functions in further cellular processes. © 2015 The Authors.


Rasch U.,TU Braunschweig | Unal C.M.,TU Braunschweig | Unal C.M.,German-Turkish University | Steinert M.,Helmholtz Center for Infection Research
Biochemical Society Transactions | Year: 2014

Legionella pneumophila, typically a parasite of free-living protozoa, can also replicate in human alveolar macrophages and lung epithelial cells causing Legionnaires' disease in humans, a severe atypical pneumonia. The pathogen encodes six peptidylprolyl cis-trans isomerases (PPIases), which generally accelerate folding of prolyl peptide bonds, and influence protein folding. PPIases can be divided into three classes, cyclophilins, parvulins and FK506-binding proteins (FKBPs). They contribute to a multitude of cellular functions including bacterial virulence. In the present review, we provide an overview of L. pneumophila PPIases, discussing their known and anticipated functions as well as moonlighting phenomena. By taking the example of the macrophage infectivity potentiator (Mip) of L. pneumophila, we highlight the potential of PPIases as promising drug targets. compilation © 2014 Biochemical Society.


Unal C.M.,German-Turkish University | Unal C.M.,TU Braunschweig | Steinert M.,TU Braunschweig | Steinert M.,Helmholtz Center for Infection Research
Microbiology and Molecular Biology Reviews | Year: 2014

Initially discovered in the context of immunomodulation, peptidyl-prolyl cis/trans isomerases (PPIases) were soon identified as enzymes catalyzing the rate-limiting protein folding step at peptidyl bonds preceding proline residues. Intense searches revealed that PPIases are a superfamily of proteins consisting of three structurally distinguishable families with representatives in every described species of prokaryote and eukaryote and, recently, even in some giant viruses. Despite the clear-cut enzymatic activity and ubiquitous distribution of PPIases, reports on solely PPIase-dependent biological roles remain scarce. Nevertheless, they have been found to be involved in a plethora of biological processes, such as gene expression, signal transduction, protein secretion, development, and tissue regeneration, underscoring their general importance. Hence, it is not surprising that PPIases have also been identified as virulence-associated proteins. The extent of contribution to virulence is highly variable and dependent on the pleiotropic roles of a single PPIase in the respective pathogen. The main objective of this review is to discuss this variety in virulence-related bacterial and protozoan PPIases as well as the involvement of host PPIases in infectious processes. Moreover, a special focus is given to Legionella pneumophila macrophage infectivity potentiator (Mip) and Mip-like PPIases of other pathogens, as the best-characterized virulence-related representatives of this family. Finally, the potential of PPIases as alternative drug targets and first tangible results are highlighted. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

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