Towards Semantic-Aware Transport Layer Protocols: A Control Performance Perspective

Networked control systems (NCSs) are an example of task-oriented communication systems, where the purpose of communication is real-time control of processes over a network. In the context of NCSs, with the processes sending their state measurements to the remote controllers, the deterioration of control performance due to the network congestion can be partly mitigated by shaping the traffic injected into the network at the transport layer (TL). In this work, we conduct an extensive performance evaluation of selected TL protocols and show that existing approaches from communication and control theories fail to deliver sufficient control performance in realistic network scenarios. Moreover, we propose a new semantic-aware TL policy, which uses the process state information to filter the most relevant updates and the network state information to prevent delays due to network congestion. The proposed mechanism is shown to outperform all the considered TL protocols with respect to control performance

Experimental Study of Transport Layer Protocols for Wireless Networked Control Systems

In Wireless Networked Control Systems (WNCSs), the feedback control loops are closed over a wireless communication network. The proliferation of WNCSs requires efficient network resource management mechanisms since the control performance is significantly affected by the impairments caused by network limitations. In conventional communication networks, the amount of transmitted data is one of the key performance indicators. In contrast, in WNCSs, the efficiency of the network is measured by its ability to facilitate control applications, and the data transmission rate should be limited to avoid network congestion. In this work, we consider an experimental setup where multiple control loops share a wireless communication network. Our testbed comprises up to five control loops that include Zolertia Re-Mote devices implementing IEEE 802.15.4 standard. We propose a novel relevance- and network-aware transport layer (TL) scheme for WNCSs. The proposed scheme admits the most important measurements for the control process into the network while taking current network conditions into account. Moreover, we propose a mechanism for the scheme parameters adaptation in dynamic scenarios with unknown network statistics. Unlike the conventional TL mechanisms failing to provide adequate control performance due to either congestion in the network or inefficient utilization of available resources, our method prevents network congestion while keeping the control performance high. We argue that relevance- and network-awareness are critical components of network protocol design to avoid control performance degradation in practice.Comment: 10 pages, 11 figure

Design of a Networked Controller for a Two-Wheeled Inverted Pendulum Robot

The topic of this paper is to use an intuitive model-based approach to design a networked controller for a recent benchmark scenario. The benchmark problem is to remotely control a two-wheeled inverted pendulum robot via W-LAN communication. The robot has to keep a vertical upright position. Incorporating wireless communication in the control loop introduces multiple uncertainties and affects system performance and stability. The proposed networked control scheme employs model predictive techniques and deliberately extends delays in order to make them constant and deterministic. The performance of the resulting networked control system is evaluated experimentally with a predefined benchmarking experiment and is compared to local control involving no delays.Comment: Submitted to IFAC Necsys 201

The efficacy of chloroquine treatment against naturally occuring Giardia duodenalis infection in lambs

Objective. The aim of the present study was to determine the efficacy of Chloroquine (Cq), an antimalarial medicine, administered at a dose of 2.5 mg/kg, orally, during 5 consecutive days, in Sakiz and Merino lambs naturally infected with Giardia duodenalis. Materials and methods. To this extent weaned 10 weeks of aged lambs were enrolled and randomly assigned into two groups based on treatment (group C, n=18 lambs treated with Cq) and placebo (group P, n=8 untreated control animals). Diagnosis was based on detection of trophozoit and/or cysts on fecal flotation. Cyst count per gram feces (days 0, 3, 7 and 10) was analyzed among groups. Results. During the trial, regarding the efficacy of Cq on days 3., 7., and 10. There was significant (p<0.01) reduction in cyst excretion; whereas evaluation of mean geometric cyst excretion revealed 100% reduction. Conclusions. There was a very high (100%) reduction in cyst excretion in the Cq treatment group compared to the positive untreated control group on days 3, 7 and 10, resulting in a significant (p<0.001) reduction, making Cq, safety, and thus highly effective treatment option of lambs with naturally occuring giardiasis. Objetivo. El objetivo del presente estudio fue determinar la eficacia de la cloroquina, un medicamento contra la malaria, administrado a una dosis de 2.5 mg/kg, por vía oral, durante 5 días consecutivos, en Corderos Sakiz y Merino infectados naturalmente con Giardia duodenalis. Materiales y metodos. En esta medida destetados 10 semanas de edad fueron incluidos y asignados al azar en dos grupos sobre la base del tratamiento (grupo C, n = 18 corderos tratados con cloroquina) y placebo (grupo P, n = 8 animales de control no tratados). El diagnóstico se basa en la detección de trophozoit y/o quistes en la flotación fecal. Quiste recuento por gramo de heces (día 0, 3, 7 y 10) se analizó entre los grupos. Resultados. Respecto a la eficacia de la cloroquina en los días 3, 7 y 10 existió una reducción significativa (p<0.01) en la excreción de quistes; mientras que la evaluación de la media de la excreción Rev.MVZ Córdoba 21(2):5328-5335, 2016. ISSN: 0122-0268 ORIGINAL 5329 de quistes reveló una reducción del 100%. Conclusiones. Durante el estudio hubo una reducción del 100% en la excreción de quistes en el grupo de tratamiento con cloroquina en comparación con el grupo control no tratado positivo en los días 3, 7 y 10, lo que resulta en una disminución significativa (p<0.001) por lo que la cloroquina razonablemente es una opción de tratamiento por el costo, seguridad, y por lo tanto muy eficaz de corderos infectados naturalmente con giardiasis

A comparative study on harmonic analysis and thermal performance of different types of lamps for residential building

This paper investigates the analysis and study of power quality, harmonics and thermal characteristics of halogen lamps, compact fluorescent lamps (CFLs) and light emitting diode lamps (LEDs). As nonlinear loads, CFLs and LEDs produce highly distorted currents compared to halogen lamps. The harmonic absorptions of each individual tested lamp are analyzed. Then, measurements with different groups of LEDs are conducted to investigate the effects of diversity factors. Although LEDs produce considerable amount of harmonics, it is concluded that amount of harmonics can be reduced by combining various types of LEDs. In addition, it could be observed that as the number of lamps increases, the diversity factor decreases. Finally, the thermal characteristics of lamps are compared in this paper. Results show that LEDs produce less heat compared to halogen lamps and CFLs

SUALTI TEKNOLOJİSİ ÖĞRENCİLERİNİN MEZUN PROFİLİ

SUALTI TEKNOLOJİSİ ÖĞRENCİLERİNİNMEZUN PROFİLİMustafa ÇEKİÇa*, Necdet UYGURb, Onur Alptekin AYANc, Deniz ERGÜDENda Mustafa Kemal Üniversitesi Hatay Sağlık Yüksekokulu Acil Yardım ve Afet Yönetimi Antakya/Hatayb,c  İskenderun Teknik Üniversitesi, Denizcilik Meslek Yüksekokulu,  Sualtı Teknolojisi Programı, İskenderun/Hatayd İskenderun Teknik Üniversitesi Deniz Bilimleri ve Teknolojisi Fakültesi,  Deniz Bilimleri. Bölümü, İskenderun/Hatay *[email protected]  ÖZETBu çalışma, İskenderun Teknik Üniversitesi ve Çukurova Üniversiteleri’nde bulunan Sualtı Teknolojisi Programları’ndan mezun olan öğrencilerin istihdam durumlarını araştırmak, mezunların sosyal ve ekonomik profilini ve öğrenim faaliyetleri hakkındaki görüşlerini ortaya çıkarmak için düzenlenmiştir. Bu araştırma için hazırlanan anket çalışması her iki üniversite mezunları ile yapılmıştır. İskenderun Teknik Üniversitesi, Denizcilik Meslek Yüksekokulu Sualtı Teknolojisi Programı 2011 yılından itibaren 76 mezun ve Çukurova Üniversitesi, Yumurtalık Meslek Yüksekokulu Sualtı Teknolojisi programı 2012 yılından itibaren 44 mezun vermiş olup, toplam her iki üniversitenin Sualtı Teknolojisi Programından şimdiye kadar 120 kişi mezun olmuştur. Araştırma da tüm mezunların tamamına ulaşılamayıp, 97 kişiye ulaşılarak anket formu doldurulmuştur.Anket sonuçlarından mezunların, %72,16’sının sualtı sektöründe, %4,12’snini turizm dalış merkezlerinde, %15,46’sının kamu kurumlarında, %1,03’ünün Sualtı Teknolojisi Bölümü’nde akademisyen olarak çalıştığı ve %7,22’sinin ise çalışmadığı görülmüştür. Anahtar Kelimeler: Sualtı Teknolojisi, Mezun, İstihdam, Mezun Profil

Task-oriented Scheduling for Networked Control Systems: An Age of Information-Aware Implementation on Software-defined Radios

Networked control systems (NCSs) are feedback control loops that are closed over a communication network. Emerging applications, such as telerobotics, drones and autonomous driving are the most prominent examples of such systems. Regular and timely information sharing between the components of NCSs is essential to fulfill the desired control tasks, as stale information can lead to performance degradation or even physical damage. In this work, we consider multiple heterogeneous NCSs that transmit their system state over a shared physical wireless channel towards a gateway node. We conduct a comprehensive experimental study on selected MAC protocols using software-defined radios with state-of-the-art (SotA) solutions that have been designed to increase information freshness and control performance. As a significant improvement over the SotA, we propose a novel contention-free algorithm that is able to outperform the existing solutions by combining their strengths in one protocol. In addition, we propose a new metric called normalized mean squared error that maps the age of information to a dimensionless quantity that captures the expected value of a control system's next transmission. We demonstrate its adoption and effectiveness for wireless resource scheduling in a case study involving multiple inverted pendulums. From our experimental study and results, we observe that value-aware prioritization of the sub-systems contributes to minimizing the negative effects of information staleness on control performance. In particular, as the number of devices increases, the benefit of control-awareness to the quality of control stands out when compared to protocols that focus solely on maximizing information freshness.Comment: Under revie