This master's thesis deals with the manufacturing of a hunting crossbow prototype. The first part summarizes the history of crossbows, their historical development and usage. The following chapter contains theoretical knowladge about the technological methods that are used in the production. This is followed by a designing of the prototype, creating a technological process and final production. Final part of this thesis evaluates individual parts of the production and the final prototype.

Trådlösa sensornät (eng. Wireless Sensor Networks, WSN) är ett snabbt växande teknikområde med många applikationer. Ett typiskt WSN består av en mängd små billiga och energisnåla enheter, så kallade sensornoder, som mäter någon miljöparameter och via radio skickar ett datapaket med uppmätt värde till en basstation som ofta är kopplad till en PC. Informationen kan därefter analyseras eller redovisas grafiskt för användaren. Sensornätverkets storlek kan variera från några få noder på en liten yta till nätverk med tusentals noder som täcker flera kvadratkilometer stora områden. Ett avsnitt om trådlösa sensornät ingår i kursen Data- och telekommunikationsteknik II, DA122T, vid Malmö högskola. Denna rapport presenterar ett examensarbete med att utveckla laborationer och studiematerial om sensornät till kursen.Utrustningen som används i laborationerna är ett paket innehållande sex sensornoder, en basstation och nödvändig programvara. Tillverkare är Crossbow Technology, världens ledande företag inom WSN.Resultatet av arbetet är två laborationshandledningar, beskrivning av utrustning som används i laborationerna samt en rapport – Introduktion till WSN. Handledningarna och det övriga materialet är skrivna på svenska.Den första laborationen, i vilken man bygger ett enkelt WSN, ger studenten förståelse för principen hos trådlösa sensornät och för hur hårdvaran och programvaran samverkar med varandra. I den andra laborationen lär sig studenten programmera sensornoder för att sedan studera kommunikationen mellan noderna och basstationen samt undersöka olika nätverkstopologier. / Wireless sensor networks, WSN, is a rapidly growing field of technology with many applications. A typical WSN consists of many small, inexpensive and energy-saving devices, called sensor nodes. These nodes measure an environmental parameter and the radio sends a data packet with the measured value to a base station, which is often connected to a PC. The information can then be analyzed and presented graphically to the user. A sensor network's size can vary from a few nodes in a small area to a network with thousands of nodes that covers several square kilometers of area. A section on wireless sensor networks is part of the course in Computer and telecommunication technologies II, DA122T, at Malmö University. This thesis reports on the development of study material for the practical laboratory motes on sensor networks for the course. The equipment used in the practical experiments is a package containing six sensor nodes, a base station and the necessary software. The manufacturers are Crossbow Technology, the world's leading company of WSN products. The results of the work are two practical exercises, a description of the equipment used in practical experiments and a report – Introduction to WSN. These guides and other materials are written in Swedish. The first lab in which to build a simple WSN, gives students an understanding of the principle of wireless sensor networks and how the hardware and software interacts with each other. In the second exercise, students will learn to program the sensor nodes to study the communication between the nodes and the base station and to explore the different network topologies.

Στην παρούσα εργασία έγινε μια πρώτη προσπάθεια ενασχόλησης με τα Ασύρματα Δίκτυα Αισθητήρων, πιο γνωστά στον επιστημονικό κόσμο ως Wireless Sensor Networks ή WSNs. Μελετήσαμε τα βασικά χαρακτηριστικά των δικτύων αυτών, όπως οι τοπολογίες τους και η αρχιτεκτονική τους. Επίσης, μελετήσαμε την αρχιτεκτονική των ασύρματων κόμβων που απαρτίζουν το δίκτυο, που είναι γνωστά σαν motes. Τα motes έχουν την ικανότητα τοπικής επεξεργασίας των δεδομένων που συλλέγουν και την ασύρματη μετάδοσή τους σε έναν κεντρικό σταθμό για περαιτέρω επεξεργασία. Τη λειτουργία αυτή διεκπαιρεώνει μια μονάδα μικροεπεξεργαστή με τη χρήση ενός ολοκληρωμένου chip για την ασύρματη μετάδοση. Για τη συλλογή των μετρήσεων μπορούν να φιλοξενήσουν διάφορες πλατφόρμες ψηφιακών αισθητήρων. Στην παρούσα εργασία έγινε χρήση της υπολογιστικής μονάδας micaz και της πλατφόρμας αισθητήρων MTS400/420. Οι πλατφόρμες αυτές φιλοξενούν αισθητήρες υγρασίας/θερμοκρασίας, βαρομετρικής πίεσης/θερμοκρασίας, φωτεινότητας, μέτρησης δονήσεων και ειδικά η 420 πλατφόρμα έχει υποδοχή και για μονάδα GPS. Σκοπός μας ήταν η ανάπτυξη ενός γραφικού περιβάλλοντος μέσω του οποίου θα απεικονίζαμε τις μετρήσεις που έστελναν στον υπολογιστή τα motes. Η ανάπτυξη του γραφικού περιβάλλοντος έγινε στο Matlab. Για το σκοπό αυτό, ήταν απαραίτητη η σύνδεση ενός mote στον υπολογιστή που θα λειτουργούσε σαν ενδιάμεσος αποδέκτης των δεδομένων και θα τα προωθούσε στον υπολογιστή μέσω της σειριακής θύρας. Για την προβολή και αποθήκευση των δεδομένων στον υπολογιστή, έγινε χρήση του interface Χlisten. / At this thesis there was a first attempt of occupation with Wireless Sensor Networks, most kown to the scientific world as WSNs. We studied the basic characteristics of these networks such as topologies and architecture. We also studied the architecture of the wireless nodes which form the network, also known as motes.The motes have the ability of local data computation and the wireless transmition of them to a base station, where they can further processed. This ability is performed by a microprocessor unit with the use of a single integrated chip responsible for the radio transmition. The data collection can be performed by many digital sensor platforms. At this paper, it has been used the micaz computional unit and the MTS400/420 sensor platform of Crossbow company. These platforms are integrated with sensors that measure relative humidity/temperature, barometric pressure/temperature, illumination, acceleration on axis x and y and especially the 420 platform can integrate a GPS module. Our goal is the development of a Graphical User Interface (GUI) through which we can plot the data that the sensors would send. The development of GUI made with Matlab. For this purpose, it was necessary the connection of a mote to the computer, that would behave like an intermediate receiver and would forward the data packets to the computer through the serial port. The MIB520 board was used for this purpose. For the data projection and saving to the computer, the xlisten interface was used.

This thesis describes the design of wireless sensor network (WSN) for monitoring of people and objects in a building. The work deals with issues of localization and tracking in sensor networks and algorithm implementation to sensor nodes. It also contains a description of the aplication requirements. These requirements form the basis for the proposal. The hardware part of the network consists of sensor nodes IRIS from Crossbow company. The work describes the properties of these nodes. Next part deals with of propagation model and design of the localization algorithm. The paper also describes the communication in the network. The thesis also includes a practical realization of the proposed network, the localization system and its testing. In the work is included a CD with the building schematic in AutoCAD and with source code of created applications.

The reader is first introduced with history and possible applications for wireless sensor networks. The thesis then describes the problems of wireless sensor networks and implementation tools for wireless sensor networks. The thesis also presents the system WSageNt and its client web interface. Practical part is based on the design of agent elements. Describes gradual implementation, testing and practical realization of these agent elements in the system WSageNt. The final part discusses the advantages and disadvantages of the project and identifies possible future expansion of the system.

How and why did plate armor come to be widely used in Medieval Europe? I trace the historical development of armor in Europe from antiquity to the middle ages, and then identify the main causes that pushed European warriors to develop and adopt plate armor from the 14th to the 16th centuries. I rely on prior research by scholars and historians of arms and armor, as well as primary source documents that describe arms and armor and their use in tournaments and on the battlefield. I conclude that a combination of social, political, military, and technical factors pushed European warriors to adopt plate armor. I also briefly discuss the demise of plate armor due to increasing use of firearms in the 16th century and the growth of professional armies.

This thesis concerns the development of optimisation algorithms to determine the relative co-location, (localisation), of a number of freely-flying 'Smart Dust mote' sensor platform elements using a non-deterministic data-set derived from the duplex wireless transmissions between elements. Smart dust motes are miniaturised, microprocessor based, electronic sensor platforms, frequently used for a wide range of remote environmental monitoring applications; including specific climate synoptic observation research and more general meteorology. For the application proposed in this thesis a cluster of the notional smart dust motes are configured to imitate discrete 'Radio Drop Sonde' elements of the wireless enabled monitoring system in use by meteorological research organisations worldwide. This cluster is modelled in software in order to establish the relative positions during the 'flight' ; the normal mode of deployment for the Drop Sonde is by ejection from an aeroplane into an upper-air zone of interest, such as a storm cloud. Therefore the underlying research question is, how to track a number of these independent, duplex wireless linked, free-flying monitoring devices in 3-dimensions and time (to give the monitored data complete spatio-temporal validity). This represents a significant practical challenge, the solution applied in this thesis was to generate 3-dimensional geometries using the only 'real-time' data available; the Radio Signal Strength Indicator (RSSI) data is generated through the 'normal' duplex wireless communications between motes. Individual RSSI values can be considered as a 'representation of the distance magnitude' between wireless devices; when collated into a spatio-temporal data-set it 'encodes' the relative, co-locational, 3-dimensional geometry of all devices in the cluster. The reconstruction, (or decoding), of the 3-dimensional geometries encoded in the spatio-temporal data-set is a complex problem that is addressed through the application of various algorithms. These include, Random Search, and optimisation algorithms, such as the Stochastic Hill-climber, and various forms of Evolutionary Algorithm. It was found that the performance of the geometric reconstruction could be improved through identification of salient aspects of the modelled environment, the result was heuristic operators. In general these led to a decrease in the time taken to reach a convergent solution or a reduction in the number of candidate search space solutions that must be considered. The software model written for this thesis has been implemented to generalise the fundamental characteristics of an optimisation algorithm and to incorporate them into a generic software framework; this then provides the common code to all model algorithms used.

A wireless sensor network consists of small, limited-resource embedded systems exchanging environment data and activating controls. These networks can be deployed in hostile environments to monitor wildlife habitats, implemented in factories to locate mobile equipment, and installed in home environments to optimize the use of utilities. Each of these scenarios requires network security to protect the network data. The IEEE 802.15.4 standard is designed for WSN communication, yet the standard states that it is not responsible for defining the initialization, distribution, updating, or management of network public keys. Individuals seeking to research security topics will find that there are many 802.15.4-compliant development hardware kits available to purchase. However, these kits are not easily compared to each other without first-hand experience. Further, not all available kits are suitable for research in WSN security. This thesis evaluates a broad spectrum of 802.15.4 development kits for security studies. Three promising kits are examined in detail: Crossbow MICAz, Freescale MC1321x, and the Sun SPOT. These kits are evaluated based on their hardware, software, development environment, additional libraries, additional tools, and cost. Recommendations are made to security researchers advising which kits to use depending on their design needs and priorities. Suggestions are made to each company on how to further improve their kits for security research.