DDS

Data Distribution Service (DDS) is the open standard for messaging using a publisher-subscriber model from Object
Management Group(OMG). DDS fosters the development of loosely coupled, modular and open architecture systems. By
supporting well-defined interfaces between components and subsystems, DDS eradicates stove-pipe, closed and proprietary
architectures. This eliminates complexity to reduce integration, maintenance and upgrade costs; promotes competition at the
subsystem and middleware levels and eases reuse. Multiple implementations of DDS are available, ranging from high-end
commercial on the shelf products to open-source community-supported projects. Every implementation claims to fit in the
standard and provides the best possible parameters for data communication but very few studies on performance analysis,
usability and features exists. The current paper bridges this gap and facilitates middleware selection by proposing a criteria set to
evaluate and compare different DDS Distributions(RTI Connext, Vortex Open Splice, OpenDDS , CoreDx and Eprosima Fast
RTPS)

In current trend, IoT emerged as the most popular advancement of Internet and became a trending technology that incorporates Machine to Machine (M2M) communication. This communication makes use of Internet protocols and various devices such as smart sensors, actuators, LTE, WLAN etc. These devices are self-configurable that collaborate with each other for exchanging the data without the inclusion of human beings. The custom of IoT through M2M communication provides unique characteristics that expand to various applications such as smart home, smart supply chain, wearable's, smart retail, military, smart farming, smart city, industrial internet, connected car, smart grids and connected health etc., which makes human lives simpler. Like network architecture, the IoT architecture also comprises three tired architecture-application tier, network tier and context-aware tier. This paper review only the application layer protocols of network tier of IoT. While the application tier, other layer of network tier and context-aware tier are out of the scope of this paper. Specifically, this paper reviews MQTT, MQTT-SN, AMQP, CoAP, XMPP, and DDS data protocols of IoT and compared these protocols with the challenging issues such as security, caching, resource discovery, support to QoS etc. Finally, we analysed the performance of these protocols with various metrics such as network packet loss rate, message size, bandwidth consumption and latency.

Individual DDS aims to reflect nutrient adequacy and have been validated for several age groups as proxy measures for nutrient adequacy. This study aims to determine if there is a significant difference in mean DDS of PSC between urban and rural communities in Occidental Mindoro, Philippines. Specifically, this study aims to determine the usual food intake of PSC among each food group. A total of four-hundred eighty (480) PSC were used as primary sampling unit. Food Agriculture Office-DDS was used in order to assess adequacy of food intake. Five (5) was used as the cutoff for diet adequacy. Mean difference and two independent population proportion was assessed using STATA software. DDS among rural communities (4.90) was lower compared to the cutoff point for adequacy; thus, it needs more priority compared to the adequacy of urban households (5.15) (p=.04). The minimum diversity score cutoff of diet adequacy among children was five (5); wherein increase in dietary score is related to dietary adequacy. Adequate dietary intake coming from varied sources was highly related to the improvement of nutritional status among children. As number of food groups increases, nutrition adequacy rating among children also increases. Furthermore, dietary intake among PSC were predominantly coming from rice-fish and vegetable combination coming from at least four to five groups. Lastly, lowest intake among food group was found in other fruits, legumes, pulses and nuts. This result would imply that there is a need to reinforce government programs which were prepared to increase the intake of the population particularly preschool children. Mean DDS among rural communities was lower compared to urban communities. Usual food patterns for both communities was combination of rice-fish and vegetable however, urban communities had higher consumption rate among food groups. Therefore, type of community must take into consideration during nutrition program planning in order to improve the diet adequacy of PSC.

— In this paper, we present three different methods we have developed for the design of an electrical impedance analyser implemented on an FPGA board. We describe in the first part the general principle of the methods: Ratiometric Measurement, Feedback Voltage Control and Adaptive Parametric Modelisation. In order to test and to compare the performances of each approach, the Hardware In the Loop strategy has been used. We present the steps from the mixed simulation using Matlab DSP Builder, which leads to the FPGA implementation. We investigate the limits and advantages for each method. The impedance analysis results of a model of an audio piezo transducer (7 kHz) are presented. The amplitude accuracy is less than 3 % and the analysis duration from 5 kHz to 10 kHz is about 54.5 ms for the first two methods.

The  increasing  complexity  in  current  distributed embedded systems (DES) makes its design a hard task that    involves    several    aspects    like    distribution middleware  selection,  QoS  support,  implementation language        selection,  application        dynamic reconfiguration    or    application    deployment    and maintenance.    These    design considerations    must provide a solution to non functional requirements that distributed    applications    nowadays    demand    (e.g. Hardware  heterogeneity,  real  time  requirements, energy constraints, security, safety or fault tolerance).
This  paper  proposes  a  management  platform  for
distributed  component  based  applications  that  follow
the  SCA  (Service  Component  Architecture)  standard.
This  platform  provides  several  functionalities  that
range  from  application  deployment  and  life  cycle
control to QoS and fault tolerance support.

NQR spectrometer designed is composed of four modules; Transmitter,
Probe, Receiver and computer controlled (FPGA & Software) module
containing frequency synthesizer, synchronous demodulator, pulse
programmer and display. The function of the Transmitter module is to
amplify the RF pulse sequence to about 200 W power level into the probe
(50 Ohm) which is a parallel resonance circuit with a tapped capacitor. The probe excites the nucleus and picks-up the signal emitted from the nuclei.  The nuclear signal at the same frequency as the excitation, which is typically in the range of a few microvolts is amplified, demodulated and filtered  (1 kHz to 100 kHz) by receiver module.
14 N NQR,  1 H and  2 H NMR signals are observed from the spectrometer.As the SNR of NQR signal is very low, NQR signal processing based on Adaptive Line Enhancement is presented.

ABSTRACT Distributed Real Time Systems (DRTS) are evolving to a higher level of complexity in terms of heterogeneity, dynamism and QoS constraints, as they must interact with an increasingly demanding environment. In an scenario with distributed applications running over different hardware platforms and networks, middleware technologies that provide real-time or QoS support are gaining importance, as they ease the development and deployment of complex distributed applications in heterogeneous networks while ensuring certain time and QoS constraints. In this sense, distribution middleware technologies like Data Distribution Service (DDS) have emerged, adding extensive QoS support to traditional middleware advantages. This paper proposes a component based applications management platform built on top of DDS that provides an easy way to deploy, configure and manage component based distributed applications, while ensuring the fulfillment of certain QoS aspects. © 2012 IFAC.

Given the new challenges that today faces networks and considering the technological advancement of communication middlewares and the protocol of communications Real Time Publish Subscribe (RTPS), this degree project, propose the implementation of the features of the RTPS protocol for be used into real time distributed applications, along with the Data Distribution (DDS) middleware.
To achieve the above-mentioned project, two libraries has been developed, corresponding to the DDS middleware and the real time communication protocol RTPS, allowing programmers develop distributed systems using these libraries and allowing has transparent communication. In addition, when a distributed system is generated, it will have the ability to self-configure according to the requirements of quality of service that is being offered.

ABSTRACT The increasing complexity in current distributed embedded systems (DES) makes its design a hard task that involves several aspects like distribution middleware selection, QoS support, implementation language selection, application dynamic reconfiguration or application deployment and maintenance. These design considerations must provide a solution to non functional requirements that distributed applications nowadays demand (e.g. Hardware heterogeneity, real time requirements, energy constraints, security, safety or fault tolerance). This paper proposes a management platform for distributed component based applications that follow the SCA (Service Component Architecture) standard. This platform provides several functionalities that range from application deployment and life cycle control to QoS and fault tolerance support.

NQR spectrometer designed is composed of four modules; Transmitter, Probe, Receiver and computer controlled (FPGA & Software) module containing frequency synthesizer, synchronous demodulator, pulse programmer and display. The function of the Transmitter module is to amplify the RF pulse sequence to about 200 W power level into the probe (50 Ohm) which is a parallel resonance circuit with a tapped capacitor. The probe excites the nucleus and picks-up the signal emitted from the nuclei. The nuclear signal at the same frequency as the excitation, which is typically in the range of a few microvolts is amplified, demodulated and filtered (1 kHz to 100 kHz) by receiver module. 14N NQR, 1H and 2H NMR signals are observed from the spectrometer.As the SNR of NQR signal is very low, NQR signal processing based on Adaptive Line Enhancement is presented.