Novel algorithms for fair bandwidth sharing on counter rotating rings

Rings are often preferred technology for networks as ring networks can virtually create fully connected mesh networks efficiently and they are also easy to manage. However, providing fair service to all the stations on the ring is not always easy to achieve. In order to capitalize on the advantages of ring networks, new buffer insertion techniques, such as Spatial Reuse Protocol (SRP), were introduced in early 2000s. As a result, a new standard known as IEEE 802.17 Resilient Packet Ring was defined in 2004 by the IEEE Resilient Packet Ring (RPR) Working Group. Since then two addenda have been introduced; namely, IEEE 802.17a and IEEE 802.17b in 2006 and 2010, respectively. During this standardization process, weighted fairness and queue management schemes were proposed to be used in the standard. As shown in this dissertation, these schemes can be applied to solve the fairness issues noted widely in the research community as radical changes are not practical to introduce within the context of a standard. In this dissertation, the weighted fairness aspects of IEEE 802.17 RPR (in the aggressive mode of operation) are studied; various properties are demonstrated and observed via network simulations, and additional improvements are suggested. These aspects have not been well studied until now, and can be used to alleviate some of the issues observed in the fairness algorithm under some scenarios. Also, this dissertation focuses on the RPR Medium Access Control (MAC) Client implementation of the IEEE 802.17 RPR MAC in the aggressive mode of operation and introduces a new active queue management scheme for ring networks that achieves higher overall utilization of the ring bandwidth with simpler and less expensive implementation than the generic implementation provided in the standard. The two schemes introduced in this dissertation provide performance comparable to the per destination queuing implementation, which yields the best achievable performance at the expense of the cost of implementation. In addition, till now the requirements for sizing secondary transit queue of IEEE 802.17 RPR stations (in the aggressive mode of operation) have not been properly investigated. The analysis and suggested improvements presented in this dissertation are then supported by performance evaluation results and theoretical calculations. Last, but not least, the impact of using different capacity links on the same ring has not been investigated before from the ring utilization and fairness points of view. This dissertation also investigates utilizing different capacity links in RPR and proposes a mechanism to support the same

Data mining in medical records for the enhancement of strategic decisions: a case study

The impact and popularity of competition concept has been increasing in the last decades and this concept has escalated the importance of giving right decision for organizations. Decision makers have encountered the fact of using proper scientific methods instead of using intuitive and emotional choices in decision making process. In this context, many decision support models and relevant systems are still being developed in order to assist the strategic management mechanisms. There is also a critical need for automated approaches for effective and efficient utilization of massive amount of data to support corporate and individuals in strategic planning and decision-making. Data mining techniques have been used to uncover hidden patterns and relations, to summarize the data in novel ways that are both understandable and useful to the executives and also to predict future trends and behaviors in business. There has been a large body of research and practice focusing on different data mining techniques and methodologies. In this study, a large volume of record set extracted from an outpatient clinic’s medical database is used to apply data mining techniques. In the first phase of the study, the raw data in the record set are collected, preprocessed, cleaned up and eventually transformed into a suitable format for data mining. In the second phase, some of the association rule algorithms are applied to the data set in order to uncover rules for quantifying the relationship between some of the attributes in the medical records. The results are observed and comparative analysis of the observed results among different association algorithms is made. The results showed us that some critical and reasonable relations exist in the outpatient clinic operations of the hospital which could aid the hospital management to change and improve their managerial strategies regarding the quality of services given to outpatients.Decision Making, Medical Records, Data Mining, Association Rules, Outpatient Clinic.

MOBİL HİDROLİK TELESKOBİK VİNÇLERDE YÜK SALINIM KONTROLÜ

Bu çalışmada, mobil hidrolik teleskobik bir vincin öncelikle tasarımı yapılmış ve burada bir yük ile vinç tanımlanmıştır. Tasarlanan teleskopik vinç gerçek sistemdeki veriler dahil edilerek Matlab/Simulink programında modellenmiştir. Giriş sinyalleri etkisiyle oluşan salınım ölçülüp bu salınımı kabul edilebilir toleranslar dahiline düşürebilecek kontrolcü tasarlanmıştır. Çalışmanın ana hedefi, mobil teleskobik vinçlerin kaldırma silindirleri ve dönme merkezindeki tork tahriki ile hareket etmesi sonucu teleskobik vince bir halat vasıtasıyla bağlı olan yükün x, y, z referans eksenlerine göre açılı bir şekilde oluşan salınımını kontrolcü kullanarak minimize etmektir. Sistemin başarı kriteri, uygulamada ergonomik bir çalışma zemini hazırlayacak şekilde salınımı azaltmak olacaktır. Göz önüne alınması gereken bir diğer nokta ise vinci kullanacak operatörden bağımsız bir şekilde bu kontrolü sağlamak olacaktır.

MOBİL HİDROLİK TELESKOBİK VİNÇLERDE YÜK SALINIM KONTROLÜ

Bu çalışmada, mobil hidrolik teleskobik bir vincin öncelikle tasarımı yapılmış ve burada bir yük ile vinç tanımlanmıştır. Tasarlanan teleskopik vinç gerçek sistemdeki veriler dahil edilerek Matlab/Simulink programında modellenmiştir. Giriş sinyalleri etkisiyle oluşan salınım ölçülüp bu salınımı kabul edilebilir toleranslar dahiline düşürebilecek kontrolcü tasarlanmıştır. Çalışmanın ana hedefi, mobil teleskobik vinçlerin kaldırma silindirleri ve dönme merkezindeki tork tahriki ile hareket etmesi sonucu teleskobik vince bir halat vasıtasıyla bağlı olan yükün x, y, z referans eksenlerine göre açılı bir şekilde oluşan salınımını kontrolcü kullanarak minimize etmektir. Sistemin başarı kriteri, uygulamada ergonomik bir çalışma zemini hazırlayacak şekilde salınımı azaltmak olacaktır. Göz önüne alınması gereken bir diğer nokta ise vinci kullanacak operatörden bağımsız bir şekilde bu kontrolü sağlamak olacaktır

Issue Report Validation in an Industrial Context

Effective issue triaging is crucial for software development teams to improve software quality, and thus customer satisfaction. Validating issue reports manually can be time-consuming, hindering the overall efficiency of the triaging process. This paper presents an approach on automating the validation of issue reports to accelerate the issue triaging process in an industrial set-up. We work on 1,200 randomly selected issue reports in banking domain, written in Turkish, an agglutinative language, meaning that new words can be formed with linear concatenation of suffixes to express entire sentences. We manually label these reports for validity, and extract the relevant patterns indicating that they are invalid. Since the issue reports we work on are written in an agglutinative language, we use morphological analysis to extract the features. Using the proposed feature extractors, we utilize a machine learning based approach to predict the issue reports' validity, performing a 0.77 F1-score.Comment: Accepted for publication in Proceedings of the 31st ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC/FSE'23

On-demand semiconductor single-photon source with near-unity indistinguishability

Single photon sources based on semiconductor quantum dots offer distinct advantages for quantum information, including a scalable solid-state platform, ultrabrightness, and interconnectivity with matter qubits. A key prerequisite for their use in optical quantum computing and solid-state networks is a high level of efficiency and indistinguishability. Pulsed resonance fluorescence (RF) has been anticipated as the optimum condition for the deterministic generation of high-quality photons with vanishing effects of dephasing. Here, we generate pulsed RF single photons on demand from a single, microcavity-embedded quantum dot under s-shell excitation with 3-ps laser pulses. The pi-pulse excited RF photons have less than 0.3% background contributions and a vanishing two-photon emission probability. Non-postselective Hong-Ou-Mandel interference between two successively emitted photons is observed with a visibility of 0.97(2), comparable to trapped atoms and ions. Two single photons are further used to implement a high-fidelity quantum controlled-NOT gate.Comment: 11 pages, 11 figure

Assessment of the requisites of microbiology based infectious disease training under the pressure of consultation needs

<p>Abstract</p> <p>Background</p> <p>Training of infectious disease (ID) specialists is structured on classical clinical microbiology training in Turkey and ID specialists work as clinical microbiologists at the same time. Hence, this study aimed to determine the clinical skills and knowledge required by clinical microbiologists.</p> <p>Methods</p> <p>A cross-sectional study was carried out between June 1, 2010 and September 15, 2010 in 32 ID departments in Turkey. Only patients hospitalized and followed up in the ID departments between January-June 2010 who required consultation with other disciplines were included.</p> <p>Results</p> <p>A total of 605 patients undergoing 1343 consultations were included, with pulmonology, neurology, cardiology, gastroenterology, nephrology, dermatology, haematology, and endocrinology being the most frequent consultation specialties. The consultation patterns were quite similar and were not affected by either the nature of infections or the critical clinical status of ID patients.</p> <p>Conclusions</p> <p>The results of our study show that certain internal medicine subdisciplines such as pulmonology, neurology and dermatology appear to be the principal clinical requisites in the training of ID specialists, rather than internal medicine as a whole.</p