Browsing by Subject "Compliance"

Now showing 1 - 4 of 4

Open Access
A miniature, foldable, collision resilient quadcopter
(2023-06) Bakır, Alihan
In the fields of surveillance, mapping and security, the use of unmanned aerial vehicles (UAVs), is becoming inevitable day by day, especially with their au-tonomous movement capabilities. The main reason for the increasing use of un- manned aerial vehicles is their ability to map and survey unknown and dangerous places such as caves without risking human life. At the same time, the ability to conduct aerial surveillance in full autonomy for public safety and health is also an important factor. Today, UAVs are used for many purposes, such as cave mapping and surveying, detection and intervention of forest fires, and inspection of outdoor and crowded areas for security purposes, often accompanied by an operator. Quadcopters are also used for missions that do not require long duration flight, as they are able to both hold position and ensure a highly stable flight. In addition to their many advantages, these UAVs are very sensitive to even the slightest impact, so their fully autonomous flight is still limited to controlled areas. Various studies are being conducted to increase the crash resistance of the quadcopters. Among these researches, there are different ideas such as protective shells and bumpers that surround the UAV and absorb the impact in case of collisions. The spherical cases that surround the UAV are usually in a mesh structure to be lightweight and not obstruct the airflow. Bumpers designed to protect the most sensitive parts of the UAV, such as the motors and propellers, are insufficient to protect the body. For these reasons, making different parts of the UAV from more flexible materials will eliminate the vulnerability of the UAV and increase its resistance to collisions. In this thesis, in order to increase the impact resistance of quadcopters and to ensure that they do not break, robots with some flexible and some rigid parts were tested and the results of these tests were evaluated in detail. During these tests, the effects of the compliance of the robot’s arms and the compliance of the bumpers protecting the propellers upon the impact were analyzed. In order to make this comparison, flexible and rigid robot bodies with dimensions as close as possible to each other, as well as rigid and flexible bumpers of similar size and structure were designed. The flexible bumper and body were produced by cutting PET sheets via a laser cutter and folding them in an origami-inspired pattern. This production method adds flexibility thanks to the thinness of the PET sheets and structural rigidity thanks to the origami-inspired folding technique. To in- crease the flexibility of the robot in the event of a collision and the stability of the motors, inserts made of TPU are inserted into the body. In addition to impact resilience, this thesis also discusses a soft sensor that can be attached to collision-resiliant drones. This sensor, made of conductive TPU, allows the robot to sense its surroundings by giving it a sense of touch. Thanks to the flexible sensor, robots can detect when a collision occurs and react accordingly. This sensor works entirely based on the flexibility of the UAV’s bumpers and senses the bending of these bumpers. Therefore, such a sensor cannot be used on rigid hulls and bumpers as they do not bend.
Open Access
Alternative dispute resolution mechanisms and compliance in international financial institutions
(2019-07) Öztürk, Emine Nur
The relationship between compliance, accountability and good governance is important in terms of the mission and role of International Organizations in global order. Although these concepts are closely related to each other, the existing literature focuses mostly on the key components of the good governance, accountability and compliance with an institution centric way. In general, relationship between compliance, accountability and good governance has been also discussed theoretically. To elaborate on these significant concepts in practice, this study investigates the role of Alternative Dispute Resolution (ADR) tools in dispute resolution as part of the compliance process in IFIs by examining the initiation, implementation and monitoring of the ADR tools in compliance and dispute resolution process. The IFIs use ADR tools in compliance review and dispute resolution as part of their accountability mechanism since ADR methods are effective tools to protect accountability of the IFIs by complying with international rules, standards and regulations including social and environmental standards. IFIs have also provided detailed information on how their ADR mechanisms work in their websites and reports. Multilateral Development Banks (MDBs) have reflected the importance of compliance review function for accountability mechanism. However, the role of ADR tools of different IFIs in compliance process has not been adequately analyzed. Considering this gap, the following research questions direct this study: How compliance processes have been initiated or conducted?, How results have been implemented?, How monitoring and evaluation of the implementation has been done? and (iv) What is the role of ADR tools in resolving the dispute?. By explaining the role of ADR tools in IFIs and selecting cases from IFIs, this study aimed to find answers for these questions which contributed to understand how compliance, accountability and good governance are related to each other in ADR mechanisms of the IFIs. Finally, the main findings of the study were reflected in conclusion section in relation to the role of the ADRs in compliance review and dispute resolution of the IFIs, which is in line with their forms, goals and missions addressing accountability and good governance.
Open Access
Damping hydrodynamic fluctuations in microfluidic systems
(Elsevier, 2018) Kalantarifard, Ali; Haghighi, Elnaz Alizadeh; Elbüken, Çağlar
In this article, we report a method to damp microfluidic hydrodynamic fluctuations caused by flow sources. We demonstrate that compliance of elastomeric off-chip tubings can be used to damp fluctuations and lead to steady flow rates. We analyze the whole microfluidic system using electrical circuit analogies, and demonstrate that off-chip compliances are significant, especially for displacement pump driven systems. We apply this hydrodynamic damping method to microfluidic droplet generation. Our results show that highly monodisperse microdroplets can be obtained by syringe pump driven systems utilizing this damping effect. We reached a coefficient of variation of 0.39% for the microdroplet area using a standard T-junction geometry. Additionally, we demonstrated that pressure pumps inherently use this effect, and have so far led the high performances reported in the literature in terms of droplet monodispersity. The presented off-chip hydrodynamic damping method is not only low-cost and practical, but can also be used in elastomeric and rigid microchannels without need to introduce additional components to the fluidic circuit.
Open Access
Model based analysis of the variation in Korotkoff sound onset time during exercise
(Institute of Physics Publishing, 2001) Türkmen, A.; Ider, Y. Z.
In this study, a minimal mathematical model of the cardiovascular system is used to study the effects of changes in arterial compliance and cardiac contractility on the onset time of Korotkoff sounds during an auscultatory procedure. The model provides blood pressure waveforms in the ventricle, the aorta and the brachial artery. From these waveforms, pre-ejection time, pulse propagation time and rise time of the blood pressure at the brachial artery can be computed. The time delay between onset time of ECG Q wave and onset time of Korotkoff sound is the sum of these three times. Rise time is zero and the time delay is minimal when the cuff pressure is slightly above the diastolic pressure. This minimum time delay is represented by QKD. Simulation results suggest that during the Bruce exercise protocol QKD decreases to one-third of its pre-exercise value if the cardiac contractility increases threefold. The effect of arterial compliance is not as significant as that of the cardiac contractility. From data recorded during an exercise test, it is observed that QKD decreases considerably as the test load is increased. We show in this study that the amount of decrease in QKD can be used as an index of the amount of increase in cardiac contractility during an exercise ECG test. Use of signal averaging for reducing the effect of motion artifacts during an exercise test is also shown to be very instrumental for making accurate QKD measurements.