157 research outputs found
A General Analytical Approximation to Impulse Response of 3-D Microfluidic Channels in Molecular Communication
In this paper, the impulse response for a 3-D microfluidic channel in the
presence of Poiseuille flow is obtained by solving the diffusion equation in
radial coordinates. Using the radial distribution, the axial distribution is
then approximated accordingly. Since Poiseuille flow velocity changes with
radial position, molecules have different axial properties for different radial
distributions. We, therefore, present a piecewise function for the axial
distribution of the molecules in the channel considering this radial
distribution. Finally, we lay evidence for our theoretical derivations for
impulse response of the microfluidic channel and radial distribution of
molecules through comparing them using various Monte Carlo simulations.Comment: The manuscript is submitted to IEEE: Transactions on Nanobioscienc
Analyzing Exchange Market Pressure Dynamics with Markov Regime Switching: The Case of Turkey
This study analyzes the dynamics of exchange market pressure in Turkey by employing the Markov regime switching model for the period from January 2006 to December 2019. Our findings show that there are two regimes in the foreign exchange market, characterized as low- and high-pressure periods. The domination of the high-pressure regime in the sample period indicates that depreciation pressure prevails in the Turkish foreign exchange market. During this regime, the pressure is aggravated by the rising inflation, credit growth, and VIX, and the falling of short-term external debt. Thus, in the presence of capital flows, the preferences of policy authorities regarding price stability and growth determine the course of the pressure. When these policy choices favor credit-driven growth, depreciation pressure in the foreign exchange market is exacerbated through the current account deficit
Determining student difficulties in solving problems related to force and motion units via hint cards
WOS: 000361659800021In order to improve students' physics problem solving skills, the points which students have difficulty in during the problem solving process must be identified. in this study, It is aimed to determine the points in which students have difficulty in by using clinic interview method with the help of hint cards. 17 different problems related to 10th class "Force and Motion" unit have been designated and 9-11 different hint cards which have the same titles for each problem have been prepared. 17 problems have been solved by 21 students studying at 2 different schools in Trabzon. Firstly, all students have been asked to solve the given problems by thinking out loud, then, students who were able to solve the problem have been asked to tell the process in details and clearly; the students who have failed to solve the problems were asked to retry solving the same problem by using hint cards. Students have come up with the correct solution for some problems without using hint cards, while for some other problems; they have needed to use the hint cards. Whereas these students, despite using hint cards, could not come up with the correct solution to some problems. It was clearly seen that students have used the hint cards which include formulas and steps of solution mostly. It was determined that there ought to be a hint card about unit conversions and the "sample solution" hint should be expressed more clearly. It was retained that some students have had superficial problem solving approach and they have difficulty in making plan, an important step in problem solving; some students have little awareness about their own problem solving process and that proposing hints can help to solve the problem only to a certain extent. Teachers have been suggested to teach the simplest steps of the problems in a clear way, to give students enough time to solve the problems by themselves, to help students find their own wrong steps in the solution process. Accordingly, researchers have been suggested to determine the difficulties that students who are at different levels have while problem solving on different topics
Molecular Signal Modeling of a Partially Counting Absorbing Spherical Receiver
To communicate at the nanoscale, researchers have proposed molecular
communication as an energy-efficient solution. The drawback to this solution is
that the histogram of the molecules' hitting times, which constitute the
molecular signal at the receiver, has a heavy tail. Reducing the effects of
this heavy tail, inter-symbol interference (ISI), has been the focus of most
prior research. In this paper, a novel way of decreasing the ISI by defining a
counting region on the spherical receiver's surface facing towards the
transmitter node is proposed. The beneficial effect comes from the fact that
the molecules received from the back lobe of the receiver are more likely to be
coming through longer paths that contribute to ISI. In order to justify this
idea, the joint distribution of the arrival molecules with respect to angle and
time is derived. Using this distribution, the channel model function is
approximated for the proposed system, i.e., the partially counting absorbing
spherical receiver. After validating the channel model function, the
characteristics of the molecular signal are investigated and improved
performance is presented. Moreover, the optimal counting region in terms of bit
error rate is found analytically.Comment: submitted to Transactions on Communication
Determination of the Middle Income Trap for Turkey and Its Sub-Regions
Bu çalışmanın amacı, orta gelir tuzağının Türkiye’nin geneli ve düzey alt bölgeleri için var olup olmadığınıincelemektedir. Çalışmada ülke geneli için orta gelir tuzağının varlığı Robertson ve Ye’nin (2013) yaklaşımındanhareketle geleneksel ve yapısal kırılmaya izin veren birim kök testleri vasıtasıyla analiz edilirken, düzey alt bölgeleriiçin başta Yakalama Endeksi (Catch-Up Index, CUI) olmak üzere istatistiki sınıflandırmalar kullanılmıştır. 1960-2018döneminin ele alındığı ekonometrik analiz sonuçlarına göre, Türkiye ekonomisinde orta gelir tuzağı mevcut değildir.Bununla birlikte 2004-2017 dönemindeki CUI değerleri, düzey alt bölgelerinin çok büyük bir kısmının düşük gelirgrubunda yer aldıklarını ve orta gelir seviyesine yükselen bazı bölgelerin de son yıllarda konumlarını kaybettiklerinigöstermektedir. Bu bağlamda, Türkiye’nin orta gelir tuzağında yer almamasını yüksek gelir grubuna doğru yakınsamaile açıklamanın güçleştiğini ifade etmek mümkündür.The aim of this study is to analyse whether there is the middle income trap for general level and sub-regions of Turkey. In this study, the existence of the middle income trap was analysed for the country level through traditional and structural break unit root tests based on Robertson and Ye's (2013) approach, on the other hand the statistical classifications -mainly Catch-Up Index (CUI)- were employed for the sub-regions. According to the results of the econometric analysis discussed in the 1960-2018 period, the middle income trap is not exist for the Turkish economy. However, CUI values for the period 2004-2017 show that a large part of the sub-regions are in the low income group and some of the regions which reached to the middle income level have lost their places in recent years. In this context, it becomes difficult to explain that Turkey’s hasn’t been stuck in middle income trap with convergence towards to the high income group
Spondyloarthropathies basic features, principles of diagnosis and treatment
Spondiloartropatiler (SPA) vertebra, periferik eklem ve eklem çevresi dokularin inflamasyonu ile karakterize bir
hastalik grubudur. Bu grup hastaliklar benzer klinik görüntü verebilirler. Etyolojilerinin kesin olarak
aydinlatilmamiş olmasina karşin, genetik yatkinlik, enfeksiyon ve çevresel etkenlerin rol oynadiği
düşünülmektedir.
Bu makalede, SPA'lerin temel özellikleri ve tedavisindeki yeni gelişmeler kisaca gözden geçirilmiştir.Spondyloarthropathies are characterised by inflammation of vertebrae, peripheral joints and periarticular tissues. Diseases in this group present with similar clinical features. Etiology is unknown but genetical tendency, infectious agents and environmental factors may play a role.
In this review main features and new approaches in treatment of spondyloarthropathies are briefly overviewed
Hematological Manifestations in Brucellosis Cases in Turkey
The hematological findings of 233 patients with brucellosis are presented and the possible pathologies discussed. Anemia was present in 128 patients (55%), leukopenia in 49 (21%) and thrombocytopenia in 59 (26%). Bone marrow aspirates of 18 patients (8%) with pancytopenia were examined. The bone marrow was hypercellular in 15 and normocellular in 3 patients. Granulomatous lesions were detected in 12 cases (67%), and slight to moderate cytophagocytosis of erythrocytes, granulocytes and platelets existed in all patients. Blood cell counts reverted to normal within 2-3 weeks of initiating chemotherapy with recovery from the disease.</p
Towards Reuse and Recycling of Lithium-ion Batteries: Tele-robotics for Disassembly of Electric Vehicle Batteries
Disassembly of electric vehicle batteries is a critical stage in recovery,
recycling and re-use of high-value battery materials, but is complicated by
limited standardisation, design complexity, compounded by uncertainty and
safety issues from varying end-of-life condition. Telerobotics presents an
avenue for semi-autonomous robotic disassembly that addresses these challenges.
However, it is suggested that quality and realism of the user's haptic
interactions with the environment is important for precise, contact-rich and
safety-critical tasks. To investigate this proposition, we demonstrate the
disassembly of a Nissan Leaf 2011 module stack as a basis for a comparative
study between a traditional asymmetric haptic-'cobot' master-slave framework
and identical master and slave cobots based on task completion time and success
rate metrics. We demonstrate across a range of disassembly tasks a time
reduction of 22%-57% is achieved using identical cobots, yet this improvement
arises chiefly from an expanded workspace and 1:1 positional mapping, and
suffers a 10-30% reduction in first attempt success rate. For unbolting and
grasping, the realism of force feedback was comparatively less important than
directional information encoded in the interaction, however, 1:1 force mapping
strengthened environmental tactile cues for vacuum pick-and-place and contact
cutting tasks.Comment: 21 pages, 12 figures, Submitted to Frontiers in Robotics and AI;
Human-Robot Interactio
- …