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Yayın Generic BER analysis of VLC channels impaired by 3D user-mobility and imperfect CSI(Institute of Electrical and Electronics Engineers Inc., 2021-07) Reddy Sekhar, K.; Miramirkhani, Farshad; Mitra, Rangeet; Turlapaty, Anish ChandVisible light communications (VLC) has emerged as a high-speed, low-cost, and green supplement for the existing radio frequency (RF) based infrastructures. However, the performance of VLC based systems is found to degrade significantly due to detrimental outages caused by non-negligible variations in the VLC channel-gain, that are jointly induced by radial user-mobility and random photodetector-orientation (together designated as 3D mobility in this letter). In addition to the 3D user-mobility mentioned above, the performance of VLC based systems is further limited by imperfect channel-state information (CSI). Such degradations in the VLC-link caused by the aforementioned factors necessitate the quantification of performance-metrics for further benchmarking/receiver-design. In this work, an analytical expression for bit-error rate (BER) is derived for a single LED indoor VLC system considering the radial user-mobility, random receiver orientation, and imperfect CSI altogether. Further, the derived BER expressions are validated using computer-simulations using typical VLC channel models from the literature. A close agreement between the analytical and the simulated BER is observed, which verifies the accuracy of the presented analysis.Yayın The cerebral blood flow deficits in Parkinson’s disease with mild cognitive impairment using arterial spin labeling MRI(Springer, 2020-09) Arslan, Dilek Betül; Gürvit, İbrahim Hakan; Genç, Ozan; Kıçik, Ani; Eryürek, Kardelen; Cengiz, Sevim; Erdoğdu, Emel; Yıldırım, Zerrin; Tüfekçioğlu, Zeynep; Uluğ, Aziz Müfit; Bilgiç, Başar; Hanağası, Haşmet Ayhan; Tüzün, Erdem; Demiralp, Tamer; Öztürk Işık, EsinParkinson's disease (PD) with mild cognitive impairment (PD-MCI) is currently diagnosed based on an arbitrarily predefined standard deviation of neuropsychological test scores, and more objective biomarkers for PD-MCI diagnosis are needed. The purpose of this study was to define possible brain perfusion-based biomarkers of not only mild cognitive impairment, but also risky gene carriers in PD using arterial spin labeling magnetic resonance imaging (ASL-MRI). Fifteen healthy controls (HC), 26 cognitively normal PD (PD-CN), and 27 PD-MCI subjects participated in this study. ASL-MRI data were acquired by signal targeting with alternating radio-frequency labeling with Look-Locker sequence at 3 T. Single nucleotide polymorphism genotyping for rs9468 [microtubule-associated protein tau (MAPT) H1/H1 versus H1/H2 haplotype] was performed using a Stratagene Mx3005p real-time polymerase chain-reaction system (Agilent Technologies, USA). There were 15 subjects withMAPTH1/H1 and 11 subjects withMAPTH1/H2 within PD-MCI, and 33 subjects withMAPTH1/H1 and 19 subjects withMAPTH1/H2 within all PD. Voxel-wise differences of cerebral blood flow (CBF) values between HC, PD-CN and PD-MCI were assessed by one-way analysis of variance followed by pairwise post hoc comparisons. Further, the subgroup of PD patients carrying the riskyMAPTH1/H1 haplotype was compared with noncarriers (MAPTH1/H2 haplotype) in terms of CBF by a two-samplettest. A pattern that could be summarized as "posterior hypoperfusion" (PH) differentiated the PD-MCI group from the HC group with an accuracy of 92.6% (sensitivity = 93%, specificity = 93%). Additionally, the PD patients withMAPTH1/H1 haplotype had decreased perfusion than the ones with H1/H2 haplotype at the posterior areas of the visual network (VN), default mode network (DMN), and dorsal attention network (DAN). The PH-type pattern in ASL-MRI could be employed as a biomarker of both current cognitive impairment and future cognitive decline in PD.Yayın Tulczyjew's triplet with an Ehresmann connection I: Trivialization and reduction(World Scientific, 2023-03-30) Esen, Oğul; Kudeyt, Mahmut; Sütlü, SerkanWe study the trivialization and the reduction of Tulczyjew's triplet, in the presence of a symmetry and an Ehresmann connection associated to it. We thus establish a geometric pathway for the Legendre transformations on singular dynamical systems.Yayın Sustainability via extended warranty contracts: design for a consumer electronics retailer(MDPI, 2024-01) Aksezer, Sezgin ÇağlarWarranty is one of the most important attributes of any product, from both manufacturer and consumer points of view. Although the retailers connect manufacturers to customers by selling goods, traditionally, they have isolated themselves from warranty-related matters such as customer complaints and maintenance costs. However, recent trends in consumer behavior toward extended warranty contracts have changed this approach. While retailers have started to generate considerable revenue from the sale of these contracts, sustainability is also achieved by longer product life cycles. This study analyzed the failure behavior of different classes of cell phone products and their related costs through a chain of consumer electronics retailer operating in Türkiye. To compete on pricing and customer service, a novel policy was designed for the retailer to honor the contracts in house rather than underwriting to a third party insurer as the industry standard. The maintenance records of 328 previous failures were analyzed to plot a failure model. Failure mode and effects analysis was carried out to identify failure classes and the respective costs for extended warranty design for cell phones. The expected warranty costs for coverage of the third, fourth, and fifth years of operation were determined. The results show that the retailer may achieve the same level of profit by increasing customer satisfaction along with the sustainability of the product through repair actions.Yayın How do local actors interpret, enact and contest policy? An analysis of local government responses to meeting the needs of Syrian refugees in Turkey(Routledge, 2022-05-04) Lowndes, Vivien; Karakaya Polat, RabiaAlthough 98% of Turkey’s 3.6 million Syrian refugees live outside camps, municipalities lack formal authority to initiate policies, while receiving no government funding for refugees. Drawing on interpretive policy analysis (IPA), the article unpacks the empirical puzzle of how formally weak local governments respond to refugee needs. IPA expects policy to be constituted through diverse sets of local meanings. Case studies in three districts in Istanbul revealed distinctive local narratives, some of which consolidated the national agenda of ‘hospitality’ while others focused on equal rights and integration. Municipal narratives reflected particular local contexts, selectively mobilizing deeper governing traditions. Local interpretations were enacted in specific approaches to refugee service delivery. Working with local NGOs, municipalities accessed international funds, despite national government’s vociferous critique of EU refugee policy. Even in an increasingly authoritarian setting, refugee policy was being constituted through multiple and contingent processes of local government interpretation.Yayın Turkish sign language adaptation of the Turkish Health Literacy Scale-32(NLM (Medline), 2022-09-15) Ataseven Bulun, Mehtap; Çepni, Selden; Ermez, YusufSign language speakers are at a disadvantage in terms of health literacy due to the lack of health education materials in sign languages. Deaf and hard of hearing (DHH) individuals are excluded from health literacy research due to the lack of measurement tools in their language of excellent f luency. This study aims to provide the literature with a tool that allows the measurement of health literacy among DHH individuals. The Turkish Health Literacy Scale (THLS)-32 was translated into Turkish Sign Language (TSL). After the THLS-32 was translated into TSL in video format, it was tested for validity and reliability. The translated version of the scale was administered to participants from a DHH association in Turkey who are f luent in TSL. Subsequently, a study was conducted with 207 DHH individuals. The study group was assessed in terms of their mean index scores and evaluated to have “limited health literacy” according to the THLS-32 classification. We conclude that the THLS-32 in TSL is suitable to measure health literacy in DHH individuals and to assess the impact of the health education system.Yayın Tribo-corrosion behavior of electroplating, nitrocarburizing, and QPQ processes on barrel finishing(Walter de Gruyter GmbH, 2023-11-27) Yücel, Aysu Hande; Yılmaz, Alpay; Bakkal, Mustafa; Kuzu, Ali TanerIn this study, the effects of nitrocarburizing, QPQ, and Cr coating on the surface properties of 32CrMoV12-10 gun barrels are discussed. Hardness measurements, pin-on-disc tests, and anodic polarization tests were performed to examine the hardness values, wear resistance, friction coefficient, and corrosion resistance. The hardness of the specimen treated with QPQ was found to be the highest. Comparing the hardness profiles, it was observed that the casing depth of the nitrocarburized sample was shallower than that of the QPQ-treated sample. The pin-on-disc test revealed that the nitrocarburized sample exhibited a high coefficient of friction, while the Cr-coated sample showed the lowest coefficient of friction. Analyzing the Tafel polarization curve, it was determined that the nitrocarburized and QPQ-treated specimens demonstrated similar levels of corrosion resistance. However, it can be noted that the QPQ-treated specimen had a slightly lower corrosion rate.Yayın A stochastic risk-averse framework for blood donation appointment scheduling under uncertain donor arrivals(Springer, 2020-12) Yalçındağ, Semih; Baş Güre, Seda; Carello, Giuliana; Lanzarone, EttoreBlood is a key resource in all health care systems, usually drawn from voluntary donors. We focus on the operations management in blood collection centers, which is a key step to guarantee an adequate blood supply and a good quality of service to donors, by addressing the so-called Blood Donation Appointment Scheduling problem. Its goal is to employ appointment scheduling to balance the production of blood units between days, in order to provide a reasonably constant supply to transfusion centers and hospitals, and reduce non-alignments between physicians' working times and donor arrivals at the collection center. We consider a two-phase solution framework taken from the literature, in which a deterministic linear programming model preallocates time slots to different blood types and a prioritization policy assigns the preallocated slots to the donors when they make a reservation. However, the problem is stochastic in nature and requires consideration of the uncertain arrivals of non-booked donors. In this work, to include the uncertain arrivals, we propose three stochastic counterparts of the preallocation model based on a risk-neutral objective and two risk-averse objectives, respectively, where the Conditional Value-at-Risk is considered as the risk measure in the last two methods. The resulting stochastic frameworks have been tested considering the historical data of one of the largest Italian collection centers, the Milan Department of the "Associazione Volontari Italiani Sangue" (AVIS). Results show the effectiveness of the stochastic models, especially the mean-risk one, and the need to include the uncertainty of arrivals in order to better balance the production of blood units.Yayın Preparing multipartite entangled spin qubits via pauli spin blockade(Nature Research, 2020-02-26) Buğu, Sinan; Özaydın, Fatih; Ferrus, Thierry; Kodera, TetsuoPreparing large-scale multi-partite entangled states of quantum bits in each physical form such as photons, atoms or electrons for each specific application area is a fundamental issue in quantum science and technologies. Here, we propose a setup based on Pauli spin blockade (PSB) for the preparation of large-scale W states of electrons in a double quantum dot (DQD). Within the proposed scheme, two W states of n and m electrons respectively can be fused by allowing each W state to transfer a single electron to each quantum dot. The presence or absence of PSB then determines whether the two states have fused or not, leading to the creation of a W state of n + m ? 2 electrons in the successful case. Contrary to previous works based on quantum dots or nitrogen-vacancy centers in diamond, our proposal does not require any photon assistance. Therefore the ‘complex’ integration and tuning of an optical cavity is not a necessary prerequisite. We also show how to improve the success rate in our setup. Because requirements are based on currently available technology and well-known sensing techniques, our scheme can directly contribute to the advances in quantum technologies and, in particular in solid state systems.Yayın Psychological distress and anxiety among housewives: the mediational role of perceived stress, loneliness, and housewife burnout(Springer, 2023-06) Durak, Mithat; Durak, Emre Şenol; Karaköse, SelinHousewives are experiencing chronic stress when dealing with multiple roles (cooking, shopping, tidying the house) in their daily life. Although earlier studies have documented a significant link between role overload and stress-psychological well-being in the workplace, few studies have been conducted among housewives despite their high anxiety and burnout reports. The diathesis-stress model and transactional model of stress indicate that there may be somecontributory factors related to mental health. Within these frameworks, this research aimed to examine housewives' psychological distress and anxiety by focusing on three contributory factors namely housewife burnout, perceived stress, and loneliness. The present study was a novel contribution to the literature investigating the mediating roles of those three contributory factors between psychological distress and anxiety among housewives. Participants were 500 volunteer housewives between the ages of 20 and 70 from Turkey. In addition to Demographic Information Form, The Perceived Stress Scales (PSS-10), The General Health Questionnaire (GHQ-12), The UCLA Loneliness Scale-Version 3 (UCLA LS3), The Housewives Burnout Questionnaire (CUBAC), and The Beck Anxiety Inventory (BAI) were used. Results showed that there were four paths between psychological distress and anxiety in the model, explaining 31.19% of the total variance in anxiety in housewives. The relationship between psychological distress and anxiety was mediated by perceived distress, loneliness, and housewife burnout. Specifically, the higher psychological distress and higher anxiety relationship were associated with higher perceived distress, higher loneliness, and higher housewife burnout. The findings provide beneficial insight for clinicians to prioritize the abandonment of the cope with loneliness, perceived stress, and burnout while working with housewives having psychological distress and anxiety.
