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Design Improvement Of The Disposable Nozzle Holder Using Topology Optimization
No full text12th Ankara Internatıonal Aerospace Conference (AIAC) 13-15 September 2023In this study, it is aimed to improve the design of the nozzle holder parts used in Two-stage nozzle engine systems by using topology optimization. The holding parts designed for the separable nozzle must first keep the engine internal pressure up to a certain level. Then the holders for the second phase are separated from the system by the special screw and the engine switches to the second phase. In this study, for an efficient design, the mass and dimensions of the holders are determined through topology optimization. The obtained massimproved part will be subjected to the strength test in the hydrostatic test setup, and the topology optimization data will be validated
A Search for New Resonances in Multiple Final States With a High Transverse Momentum Z Boson in ?s = 13 Tev Pp Collisions With the Atlas Detector
No full textA generic search for resonances is performed with events containing a Z boson with transverse momentum greater than 100 GeV, decaying into e + e ? or ? + ? ?. The analysed data collected with the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider correspond to an integrated luminosity of 139 fb?1. Two invariant mass distributions are examined for a localised excess relative to the expected Standard Model background in six independent event categories (and their inclusive sum) to increase the sensitivity. No significant excess is observed. Exclusion limits at 95% confidence level are derived for two cases: a model-independent interpretation of Gaussian-shaped resonances with the mass width between 3% and 10% of the resonance mass, and a specific heavy vector triplet model with the decay mode W? ? ZW ? ??qq. [Figure not available: see fulltext.] © 2023, The Author(s).21/SCI/017; IN2P3-CNRS; SCI/013We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TENMAK, Türkiye; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, Compute Canada and CRC, Canada; PRIMUS 21/SCI/017 and UNCE SCI/013, Czech Republic; COST, ERC, ERDF, Horizon 2020 and Marie Sk?odowska-Curie Actions, European Union; Investissements d’Avenir Labex, Investissements d’Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014–2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Göran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom
Reliability and Availability Analysis for Electronic Circuit Design
No full textMarmara University10th International Conference on Electrical and Electronics Engineering, ICEEE 2023 -- 8 May 2023 through 10 May 2023 -- 194296This paper provides a reliability, availability and Mean Time Between Failure (MTBF) analysis for a sample DC/DC converter and Discrete I/O electronic circuit stages. These analyses were performed using the Failure Tree Analyses (FTA) approach. The reason for choosing these structures is that they are frequently used in today's electronic design. In this study, the effect of the importance of reliability on the whole system, starting from a component in electronic circuit design, has been demonstrated. © 2023 IEEE
Scalable Fabrication of Mxene-Pvdf Nanocomposite Triboelectric Fibers Via Thermal Drawing
No full textIn the data-driven world, textile is a valuable resource for improving the quality of life through continuous monitoring of daily activities and physiological signals of humans. Triboelectric nanogenerators (TENG) are an attractive option for self-powered sensor development by coupling energy harvesting and sensing ability. In this study, to the best of the knowledge, scalable fabrication of Ti3C2Tx MXene-embedded polyvinylidene fluoride (PVDF) nanocomposite fiber using a thermal drawing process is presented for the first time. The output open circuit voltage and short circuit current show 53% and 58% improvement, respectively, compared to pristine PVDF fiber. The synergistic interaction between the surface termination groups of MXene and polar PVDF polymer enhances the performance of the fiber. The flexibility of the fiber enables the weaving of fabric TENG devices for large-area applications. The fabric TENG (3 x 2 cm(2)) demonstrates a power density of 40.8 mW m(-2) at the matching load of 8 M omega by maintaining a stable performance over 12 000 cycles. Moreover, the fabric TENG has shown the capability of energy harvesting by operating a digital clock and a calculator. A distributed self-powered sensor for human activities and walking pattern monitoring are demonstrated with the fabric.Scientific and Technological Research Council of Turkey (TUBITAK) [20AG001]This work was partially supported by the Scientific and Technological Research Council of Turkey (TUBITAK) 1004 program (Project #20AG001). The authors would like to thank Dr. A. Erbas for his useful comments and Mr. C. Guven for his assistance with hot-pressing
Dna-Au (111) Interactions and Transverse Charge Transport Properties for Dna-Based Electronic Devices
No full textDNA's charge transfer and self-assembly characteristics have made it a hallmark of molecular electronics for the past two decades. A fast and efficient charge transfer mechanism with programmable properties using DNA nanostructures is required for DNA-based nanoelectronic applications and devices. The ability to integrate DNA with inorganic substrates becomes critical in this process. Such integrations may affect the conformation of DNA, altering its charge transport properties. Thus, using molecular dynamics simulations and first-principles calculations in conjunction with Green's function approach, we explore the impact of the Au (111) substrate on the conformation of DNA and analyze its effect on the charge transport. Our results indicate that DNA sequence, leading to its molecular conformation on the Au substrate, is critical to engineer charge transport properties. We demonstrate that DNA fluctuates on a gold substrate, sampling various distinct conformations over time. The energy levels, spatial locations of molecular orbitals and the DNA/Au contact atoms can differ between these distinct conformations. Depending on the sequence, at the HOMO, the charge transmission differs up to 60 times between the top ten conformations. We demonstrate that the relative positions of the nucleobases are critical in determining the conformations and the coupling between orbitals. We anticipate that these results can be extended to other inorganic surfaces and pave the way for understanding DNA-inorganic interface interactions for future DNA-based electronic device applications.We acknowledge NSF ECCS Grant Numbers 1807391 and 1807555. We acknowledge using the Hyak supercomputer system at the University of Washington and TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRUBA resources). Busra Demir further acknowledges a TUBITAK 2214-A International Doctoral Research Fellowship.NSF ECCS [1807391, 1807555]; International Doctoral Research Fellowship [TUBITAK 2214-A
Effects of High-Intensity Interval Training (hiit) on Skeletal Muscle Atrophy, Function, and Myokine Profile in Diabetic Myopathy
No full textPurpose: Diabetes is a metabolic disorder characterized by chronic hyperglycemia due to insulin deficiency and/or loss of its action. Diabetic myopathy causes functional limitations in diabetic patients. The beneficial effects of high-intensity interval training (HIIT) are widely reported. We have hypothesized that HIIT application would prevent the development of diabetic myopathy. Methods: Male, Wistar albino rats (10 W) were randomly divided into four groups (1)Control(C), (2)Diabetes(DM), (3)Training(HIIT), and (4)Diabetes + Training(DM + HIIT). Streptozotocin(60 mg/kg) was injected for the induction of diabetes. The maximum exercise capacity(MEC) of animals was determined by an incremental load test. HIIT protocol (4 min 85–95 % MEC, 2 min 40–50 % MEC, 6 cycles, 5 days/week) was applied for 8 weeks. In the end, functional parameters, atrophy, and resistance to fatigue in soleus and EDL muscles were evaluated. IL-6, FNDC5, and myonectin levels were measured in EDL, soleus, and serum. Results: We observed atrophy, fatigue sensitivity, and proinflammatory alterations (IL-6 increase) in the EDL samples due to diabetic myopathy which were not observed in the soleus samples. HIIT application prevented the aforementioned detrimental alterations. Both force-frequency response and parallelly the twitch amplitude increased significantly in the DM + HIIT group. Half relaxation time (DT50) increased in both exercising and sedentary diabetics. FNDC5 was significantly higher in the exercising animals in soleus samples. Myonectin was significantly higher in the soleus muscle only in the DM + HIIT group. Conclusion: Current findings show that diabetic myopathy develops earlier in glycolytic-fast-twitch fibers(EDL) than in oxidative-slow-twitch fibers(soleus). Furthermore, HIIT application prevents atrophy in skeletal muscle, increases resistance to fatigue, and has an anti-inflammatory effect. New findings: The current study analyzes the myokine profile and skeletal muscle function under the effect of diabetes HIIT-type exercise. We also measured maximal exercise capacity and tailored the exercise program individually according to the result. Diabetic myopathy is an important complication of diabetes yet still, it is not understood completely. Our results show that HIIT-type training would be beneficial in diabetic myopathy but further investigation is needed to understand the whole molecular mechanism. © 2023 Elsevier Ltd21B0230016This study was funded by AU BAP (21B0230016) and presented as oral communication in 47. National Physiology Congress, Antalya, Turkey. We would like to express our gratitude to Dr. Ahmet Mert ERTUNÇ for sharing his methodological information with us
Search for Flavour-Changing Neutral Current Interactions of the Top Quark and the Higgs Boson in Events With a Pair of Τ-Leptons in Pp Collisions at √s=13 Tev With the Atlas Detector
No full textA search for flavour-changing neutral current (FCNC) tqH interactions involving a top quark, another up-type quark (q = u, c), and a Standard Model (SM) Higgs boson decaying into a tau-lepton pair (H -> tau(+)tau(-)) is presented. The search is based on a dataset of pp collisions at root s = 13 TeV that corresponds to an integrated luminosity of 139 fb(-1) recorded with the ATLAS detector at the Large Hadron Collider. Two processes are considered: single top quark FCNC production in association with a Higgs boson (pp -> tH), and top quark pair production in which one of top quarks decays into Wb and the other decays into qH through the FCNC interactions. The search selects events with two hadronically decaying tau-lepton candidates (tau(had)) or at least one tau(had) with an additional lepton (e, mu), as well as multiple jets. Event kinematics is used to separate signal from the background through a multivariate discriminant. A slight excess of data is observed with a significance of 2.3 sigma above the expected SM background, and 95% CL upper limits on the t -> qH branching ratios are derived. The observed (expected) 95% CL upper limits set on the t -> cH and t -> uH branching ratios are 9.4x10(-4)(4.8(-1.4)(+2.2) x 10(-4)) and 6.9x10(-4) (3.5(-1.0)(+1.5) x10(-4)), respectively. The corresponding combined observed (expected) upper limits on the dimension-6 operator Wilson coefficients in the effective tqH couplings are C-c phi 1.35 (0.97) and C-u phi 1.16 (0.82).ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW; FWF, Austria; ANAS; CNPq; FAPESP, Brazil; NSERC; CFI, Canada; NSFC, China; MEYS CR, Czech Republic; DNRF; DNSRC, Denmark; IN2P3-CNRS; CEA-DRF/IRFU, France; BMBF; MPG, Germany; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT; JSPS, Japan; CNRST, Morocco; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS; MIZS, Slovenia; MICINN, Spain; Wallenberg Foundation, Sweden; SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; DOE; NSF, United States of America; BCKDF; CANARIE; CRC, Canada [PRIMUS 21/SCI/017, UNCE SCI/013]; Czech Republic; ERC; ERDF; Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex; ANR, France; DFG; AvH Foundation, Germany - EU-ESF; Greek NSRF, Greece; BSF-NSF; NCN; La Caixa Banking Foundation; CERCA Programme Generalitat de Catalunya; PROMETEO; Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; Royal Society; Leverhulme Trust, United Kingdom; NDGF (Denmark, Norway, Sweden); KIT/GridKA (Germany); INFN-CNAF (Italy); NL-T1 (Netherlands), PIC (Spain); ASGC (Taiwan); BNL (USA) [122]; NWO, NetherlandsWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TENMAK, Turkiye; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, Compute Canada and CRC, Canada; PRIMUS 21/SCI/017 and UNCE SCI/013, Czech Republic; COST, ERC, ERDF, Horizon 2020 and Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom.; The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of computing resources are listed in ref. [122]
Fatigue Life Prediction of Lattice Structures Using a Strain-Life Method Based on an Equivalent Solid Model
No full textIn this study, an efficient fatigue life estimation approach is proposed based on an equivalent solid model, along with two stress concentration factors, instead of a lattice model to simplify simulations for the strain-life method. One of the stress concentration factors accounts for the stress concentrations at the strut joints in lattice structures without any manufacturing effect, while the other accounts for the stress concentrations due to surface defects on the struts introduced by the additive manufacturing process. A simple solid cell, for which the dimensions are the same as those of the lattice cell, is first used to estimate the fatigue life of the bulk material used in the additive manufacturing process using the Brown-Miller strain-life method. Combinations of two stress concentration factors were then utilized to predict the fatigue life of the lattice structure from the equivalent solid model. Using this approach, computationally expensive lattice structure simulations were eliminated, and the fatigue life of the lattice structure was predicted directly from the bulk material fatigue life estimation. The proposed approach was applied to different lattice types made of Ti-6Al-4V alloy using the laser-powder bed fusion additive manufacturing process. The fatigue life results estimated using the proposed approach were in good agreement with the experimental fatigue life results reported in the literature
Security-Aware Database Migration Planning
No full textArticle; Early AccessDatabase migration is an important problem faced by companies dealing with big data. Not only is migration a costly procedure, but it also involves serious security risks as well. For some institutions, the primary focus is on reducing the cost of the migration operation, which manifests itself in application testing. For other institutions, minimizing security risks is the most important goal, especially if the data involved is of a sensitive nature. In the literature, the database migration problem has been studied from a test cost minimization perspective. In this paper, we focus on an orthogonal measure, i.e., security risk minimization. We associate security with the number of shifts needed to complete the migration task. Ideally, we want to complete the migration in as few shifts as possible, so that the risk of data exposure is minimized. In this paper, we provide a formal framework for studying the database migration problem from the perspective of security risk minimization (shift minimization) and establish the computational complexities of several models in the same. For the NP-hard models, we develop memetic algorithms that produce solutions that are within 10% and 7% of the optimal in 95% of the instances under 8 and 82 seconds, respectively.Defense Advanced Research Projects Agency [HR001123S0001-FP-004]AcknowledgementsThis research was supported in part by the Defense Advanced Research Projects Agency through grant HR001123S0001-FP-004