Communication System

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This study explores how innovations surrounding supply chain communication systems (SCCS) affect channel relationships and market performance. Drawing on the resource-based view of the firm, the study hypothesizes that certain SCCS innovations can be viewed as firm resources that enhance channel capabilities, which in turn affect a firm’s market performance. The empirical research is based on 184 responses from a survey with U.S. supply chain and logistics managers using structural equation modeling as the analytic method. The results suggest that the effect of applied technological SCCS innovations on channel capabilities is mediated by interfirm systems integration. In contrast, administrative SCCS innovations enhance information exchange and coordination activities directly. Furthermore, the influence of applied technological innovations for SCCS is not strong enough to affect either responsiveness of the partnership or firm performance, whereas administrative innovations for SCCS affect both.

The photophores of Meganyctiphanes were investigated with regard to the control of light production and with respect to their role in a hitherto unknown communication system using light flashes which became evident from observation of specialised signalling behaviour. To that purpose the light production was recorded during presentation of a range of stimuli delivered to the intact, tethered shrimp. Stimuli used were changes in ambient light, water turbulence, simulated predator approach and light flashes, as well as electric shocks and serotonin injections. Strong negative light gradients, exaggerating the natural sunset signal, reliably elicited light production, the peak of which lasted on average 2 min. In the late phase of this light production, low frequency water oscillations and turbulent flow (assumed intraspecific communication signals at close range) elicited transient increases in light production. Artificial light flashes presented to a group of shrimp evoked a signalling behaviour in which the animal points the light of its photophore beamers (positioned at the ventral side and normally directed downwards) for a fraction of a second at observers within the same depth level. The responses produced by the signalling behaviour indicate a fixed delay with respect to the triggering flash. Electric stimulation of the ventral nerve cord via implanted electrodes resulted in a strong light production with a latency of 160 ms. Injection of serotonin, resulting in haemolymph concentrations of 10–5 M and higher, initiated increasingly strong and increasingly long-lasting continuous light production. Implications for the control of the photophores are discussed.

This project proposes that language evolve through reinforcement learning where agents communicate with each other and provide rewards if communication is successful. The fundamental difference between the learning mechanisms that humans use to communicate with one another and how machines learn to communicate is that the system used by humans presupposes that the adult already knows the meanings associated with the human language. Languages evolve historically to be optimal communication systems where human language learning mechanisms have evolved in order to learn these systems more efficiently. Machines in their learning of natural language, have to start at a place that humans mastered thousands of years ago. Uttering previously unheard signals and collectively establishing meaning. The question that this paper deals with is how can a communication system evolve if none of the conspirators have mastered the system previously using evolutionary computation and reinforcement lear...

Effective IT governance will ensure alignment between IT and business goals. Organizations with ineffective IT governance will suffer due to poor performance of IT resources such as inaccurate information quality, inefficient operating costs, runaway IT project and even the demise of its IT department. This study seeks to examine empirically the individual IT governance mechanisms that influence the overall effectiveness of IT governance. Furthermore, this study examines the relationship of effective IT governance, the extent of IT outsourcing decisions within the organizations, and the level of IT Intensity in the organizations. We used structural equation modeling analysis to examine 110 responses from members of ISACA (Information Systems and Audit Control Association) Australia in which their organizations have outsourced their IT functions. Results suggest significant positive relationships between the overall level of effective IT governance and the following mechanisms: the i...

Summary form only given. It is well known that despite all of its advantages the digital revolution also leads to large variety of new risks. One principal issue in this context is the growing dependence of our modern information society from the availability and correct (proved) function of modern communication services. First, I'll give a short overview on threats in communication networks (grids, clouds, etc), protocols and secure personal devices. Then I'll discuss current network security approaches based on anonymous message exchanges within communicating systems. Cryptography was first used to ensure data confidentiality, it has been “democratized” by ensuring the safety of telecommunications services, thereby extending its scope to authentication of a person or device, or a message, non-repudiation, integrity but also the anonymity of transactions. The anonymity is sometimes quite important in the new telecommunication and mobile networks services, much more than just message confidentiality. The talk will focus on some examples and new approaches developed in our research laboratory to deal with anonymity in routing protocols for mobile communicating systems.

Abstract: The size, complexity and performances of modern wireless communication circuits are getting more and more challenging whereas marketing time and cost must be reduced as much as possible. In order to fill the current lack in CAD tools, this work is dedicated to the mixed simulation of complete communication systems driven by digital and digitally modulated RF signals. This paper describes a methodology for top-down design, modeling, and simulation of complete RF system using hardware description language VHDL-AMS (Very high speed integrated circuit Hardware Description Langage – Analog Mixed Signal). As application, we consider a complex M-QAM system (transmitter, channel, and receiver) and we show some details of

As aberrant behavior is often recognized as the number one form of communication, it becomes imperative that as parents, teachers, and educators we must address and system-atically teach or provide all children with an effective means of communication. While many augmentative and alternative communication systems such as manual sign lan-guage and the Picture Exchange Communication System (Frost & Bondy, 1994) have shown tremendous success, some students with developmental disabilities students unique needs require more individually tailored communication training that necessitates empirical inquiry and use of collective expertise. Doing so may facilitate the acquisition of skills and behaviors that improve communication skills through independent appropri-ate means for meeting students’ personal needs and desires. This article systematically provides a variation of the Picture Exchange Communication System (PECS) including materials, resources, and methodology necessary to implement...

In many packet-based communication systems such as TCP/IP-based systems, packets are communicated over a noisy physical layer (a channel), and if a packet cannot be decoded correctly, then the transport layer retransmits it. Of course, retransmissions consume significant resources and their use should be limited. However, decreasing the likelihood of retransmission requires to encode the packets with strong channel codes in the physical layer, which also requires additional channel resources. In this paper, we study the cross-layer tradeoff between coding and packet retransmissions, and optimize over the total channel resource consumption. We show that as the packet length k increases, the redundancy r beyond the k/C channel uses implied by Shannon's channel capacity C is Theta(radickln(k)) extra channel uses. Moreover, as k increases we must use stronger channel codes. We then apply these results to universal coding over a piecewise memoryless channel with transitions between unknown i.i.d. statistics. Our constructive universal algorithm has redundancy r=O(k2/3radicln(k)) using packets of polynomially increasing lengths while accounting for possible packet drops caused by transitions in the statistics.

In this work both the multimodal hypergraph and the viable hyperpath conceptualizations are presented. The shortest viable hyperpath problem (SVHP) in a multimodal transportation network is defined. We consider a label correcting approach to find the shortest viable hyperpath from an origin to a destination, for different values of the upper limit of modal transfers. Such hyperpaths compose a Pareto-optimal

In satellite networks, voice over IP performance is degraded by long delays and low bandwidth. Both call setup time and quality of service (QoS) for voice calls are affected. Separate studies have been undertaken for these performance metrics. In this paper, we have carried out experiments using different voice codecs to evaluate SIP call setup time and QoS parameters together.

Page 1. FAST ACTIVE CONSTELLATION EXTENSION FOR MIMO-OFDM PAR REDUCTION Brian S. Krongold ARC Special Research Centre for Ultra-Broadband Information Networks Dept. of Electrical & Electronic Engineering University of Melbourne, Australia ...

Natural disaster of tsunami have occurred in Indonesia, Thailand, India, the Maldives and Sri Lanka after an earthquake measuring 9.0 on the Richter scale erupted, on Dec 26, 2004 of Sunday morning centered near the Indonesian island of Sumatra. The tsunamis washed away fishing villages and resorts throughout the region. The biggest tsunami on history has hit Aceh on Dec 26, 2004. In Banda Aceh as well as several coastal cities in Aceh, many people are not aware and care about the sign of nature before wave came. On the contrary, in a small island Simelue, the local people were aware of the sign of nature, and they know how to avoid the incoming wave and where to evacuate. The tsunami warning can be circulated via established communication systems to issue timely alarms to permit evacuation of coastal areas. Such high-technology warning system is surely needed high funding. Moreover, the sign of nature from animal behavior can be used potentially as a low-technology warning system t...

In the battlefield of the future, more and more information will be available for making decisions on a tactical level, provided that this information can be dispersed rapidly and accurately. As a consequence, advanced tactical decision support that now is limited to advanced platforms (e.g. combat aircrafts) will become available at a much lower level, ranging from different kind of

Recent advances in technology and wireless sensor networks made new trends to emerge in agriculture sector. One such new trend is Precision Agriculture(PA). This paper presents an automatic Irrigation Controller for precision agriculture. The irrigation controller regulates the desired moisture level in agricultural soil by making the irrigation pump on or off based on the sensor readings. This controller efficiently monitors moisture level in soil and proves efficient in both dry and heavy rainfall conditions.