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This dissertation applies theories and concepts of wireless communications and signal processing to the security domain to assess the security of a Wireless secret Key Generation (WKG) system against capable eavesdroppers, who employ all the feasible tools to compromise the system’s security. The security of WKG is evaluated via real wireless measurements, where adversary knows and applies appropriate signal processing tools in ordere to predict the generated key with the communicating pair. It is shown that in a broadband stationary wireless communication channel, (e.g. commercial off-the-shelf 802.11 WLAN devices), a capable eavesdropper can recover a large portion of the secret key bits. However, in an Ultra-wideband (UWB) communication, at the same stationary environment, secret key rates of 128 bits per channel probe are achievable. / Graduate

Spacecrafts are extensively used by public and private sectors to support a variety of services. Considering the cost and the strategic importance of these spacecrafts, there has been an increasing demand to utilize strong cryptographic primitives to assure their security. Moreover, it is of utmost importance to consider fault tolerance in their designs due to the harsh environment found in space, while keeping low area and power consumption. The problem of recovering spacecrafts from failures or attacks, and bringing them back to an operational and safe state is crucial for reliability. Despite the recent interest in incorporating on-board security, there is limited research in this area. This research proposes a trusted hardware module approach for recovering the spacecrafts subsystems and their cryptographic capabilities after an attack or a major failure has happened. The proposed fault tolerant trusted modules are capable of performing platform restoration as well as recovering the cryptographic capabilities of the spacecraft. This research also proposes efficient fault tolerant architectures for the secure hash (SHA-2) and message authentication code (HMAC) algorithms. The proposed architectures are the first in the literature to detect and correct errors by using Hamming codes to protect the main registers. Furthermore, a quantitative analysis of the probability of failure of the proposed fault tolerance mechanisms is introduced. Based upon an extensive set of experimental results along with probability of failure analysis, it was possible to show that the proposed fault tolerant scheme based on information redundancy leads to a better implementation and provides better SEU resistance than the traditional Triple Modular Redundancy (TMR). The fault tolerant cryptographic primitives introduced in this research are of crucial importance for the implementation of on-board security in spacecrafts.

Understanding how populations are structured and how they use natural and anthropogenic spaces is essential for effective wildlife management. A total of 510 barren-ground (Rangifer tarandus groenlandicus), 176 boreal (R. t. caribou), 11 mountain woodland (R. t. caribou), and 39 island (R. t. groenlandicus x pearyi) caribou were tracked with satellite collars in 1993-2009 in the Northwest Territories, Nunavut, and northern Alberta. Using satellite location data and hierarchical and fuzzy cluster analyses, I verified that Cape Bathurst, Bluenose-West, Bluenose-East, Bathurst, Beverly, Qamanirjuaq, and Lorillard barren-ground subpopulations were robust; the Queen Maude Gulf and Wager Bay barren-ground subpopulations were distinct. Dolphin and Union island caribou formed one population; boreal caribou formed two distinct subpopulations. Females in robust subpopulations were structured by strong annual spatial affiliation; those in distinct subpopulations were spatially independent and structured by migratory connectivity, movement barriers, and/or habitat discontinuity. An east-west cline in annual-range sizes and path lengths supported the subpopulation structure identified for migratory barren-ground caribou. I analyzed satellite location data to determine parturition dates and activity periods for all caribou ecotypes. For parturition dates I found a north-south cline for boreal caribou, west-east cline for migratory barren-ground caribou, and ecotype and subspecies clines for boreal and barren-ground caribou. Based on annual changes in movement rates I identified eight activity periods for boreal and tundra-wintering, 10 for mountain woodland, and 12 for migratory barren-ground caribou. Based distribution and movements, boreal caribou avoided seismic lines during periods when females and calves were most vulnerable to predators or hunters. They crossed fewer seismic lines and travelled faster when they crossed them than expected. Caribou avoided areas ≤400 m from seismic lines where they could space away from them suggesting that they perceive these as risky areas. I defined secure habitats as areas that were >400 m from anthropogenic linear features. Population growth rates were higher in areas where they had access to secure unburned habitat and where most of that was in patches >500 km2. Critical habitat for boreal caribou is a habitat state that provides “security” from predation risk and facilitates the effectiveness of their anti-predator strategies. / Ecology

雙方相等性驗證即是在不洩漏任何自身私密資訊的情況下，進行秘密計算來了解彼此的資訊是否相等。然而在大多數的現有協議之中，多數為不公平的協定，也就是說其中的一方(被告知方)只能相信另一方(告知方)所告知的比較結果，而無從驗證。雖然邱等學者在2011 年提出的〝具隱私保護功能之兩方相等性驗證機制之提案〞已經提供了具雙方驗證的協定，但此方案因為在加密演算法上的限制導致實作較為困難。因此，在本論文中，將利用ElGamal 的加密機制，提出了一套新的雙方相等性驗證的協議，具備相同的雙方相等性驗證的功能，但對加密演算法的限制較少，實作及運算也較為有效率。另外，搭配模糊傳輸的協定，讓使用者藉由本研究所提出的協定跟伺服器端溝通，來獲得所欲取得的資料，並同時保障使用者以及伺服器端的隱私。同時除了理論的證明安全性及正確性之外，也撰寫程式模擬並證實協定的正確性及討論其效能。 / Two-party equality testing protocol allows two entities to compare their secrete information without leaking any information except the comparison result. In previous works, the comparison result can only be obtained by one entity (ie. informer) and then the entity informs the result to the other entity (ie. receiver). The receiver has to accept the received result since he has no way to verify its correctness. Ciou et al. in 2011 first mentioned this problem and proposed a new protocol to solve the aforementioned problem. However, their protocol has some specific restrictions which making it unpractical. In this paper, based on the ElGamal encryption, we propose a new two-party equality testing protocol. Our protocol has the same feature (ie. allows the two entries to test the correctness of the comparison result) as Ciou et al.’s protocol but is more efficient and practical than theirs. On the other hand, combining our protocol with an oblivious transfer protocol can let users communicate with servers and to get the data in a private way. It is useful on the issue of privacy protection. Finally, the security and correctness are discussed and proved. The efficiency of the protocol is also provided.

Voting is a fundamental decision making instrument in any consensus-based society. It is employed in various applications from student body elections, reality television shows, shareholder meetings, to national elections. With the motivation of better eciency, scalability, speed, and lower cost, voting is currently shifting from paper-based to the use of electronic medium. This is while aiming to achieve better security, such that voting result reflects true opinions of the voters. Our research focuses on the study of cryptographic voting protocols accommodating a flexible ballot structure as a foundation for building a secure electronic voting system with acceptable voting results. In particular, we search for a solution suitable for the preferential voting system employed in the Australian Federal Election. The outcomes of the research include: improvements and applications of batch proof and verication theorems and techniques, a proposed alternative homomorphic encryption based voting scheme, a proposed Extended Binary Mixing Gate (EBMG) mix-network scheme, a new threshold randomisation technique to achieve receipt-freeness property in voting, and the application of cryptographic voting protocol for preferential voting. The threats and corresponding requirements for a secure secret-ballot voting scheme are rst discussed. There are significant security concerns about the conduct of electronic voting, and it is essential that the voting results re ect the true opinions of the voters - especially in political elections. We examine and extend batch processing proofs and verifications theorems and proposed applications of the theorems useful for voting. Many instances of similar operations can be processed in a single instance using a batch technique based on one of the batch theorems. As the proofs and verications provide formal assurances that the voting process is secure, batch processing offers great efficiency improvements while retaining the security required in a real-world implementation of the protocol. The two main approaches in cryptographic voting protocols, homomorphic encryption based voting and mix-network based voting, are both studied in this research. An alternative homomorphic voting scheme using multiplicative homomorphism property, and a number of novel mix-network schemes are proposed. It is shown that compared to the mix-network approach, homomorphic encryption schemes are not scalable for straight-forward adaptation of preferential systems. One important requirement of secret-ballot voting is receipt-freeness. A randomisation technique to achieve receipt-freeness in voting is examined and applied in an ecient and practical voting scheme employing an optimistic mix-network. A more general technique using threshold randomisation is also proposed. Combination of the primitives, both the homomorphic encryption and mixnetwork approach, yields a hybrid approach producing a secure and ecient secret-ballot voting scheme accommodating a exible ballot structure. The resulting solution oers a promising foundation for secure and practical secret-ballot electronic voting accommodating any type of counting system.

Thesis (Engineer's) --Naval Postgraduate School, 1976. / "September 1976." "AD A035848." Includes bibliographical references (leaves 122-123) Available via the Internet.

Les travaux présentes dans cette thèse s'inscrivent dans le cadre des méthodes d'évacuation des populations. Ils visent à étudier les capacités et modéliser le problème d'évacuation (blessés, sinistrés, enfants, personnes agées, etc.) dans une situation de crise (attentats terroristes, catastrophes naturelles, etc.) et développer des méthodes d'aide à la décision tout en proposant une meilleure planification et des plans optimaux d'évacuation des populations de la zone de crise vers les centres hospitaliers.Notre travail consiste à résoudre le problème d'évacuation de blessés dans des zones de crise avec une nouvelle vision qui consiste à optimiser le temps de transport et par conséquent sauver le maximum des personnes touchées par cette crise d'une façon dynamique, efficace et rapide pour minimiser la perte humaine. / The work presented in this thesis is part of human evacuation methods. It aims to study the capacities, model the evacuation problem (wounded, victims, children, elderly, etc.) in a crisis situation (terrorist attacks, natural disasters, etc.) and to develops methods for decision making while proposing better planning and optimal evacuation plans for populations from the crisis zone to hospitals.Our job is to solve the wounded evacuation problem in crisis zone with a new vision that optimizes the transport time and thus saving the maximum of causalities in a dynamic, efficient and fast way in order to minimize human loss.

Text in Afrikaans / Skrywers oar die gesin kom al hoe meer tot die slotsom dat die gesin onvervangbaar is in die sosialiseringsproses van die mens. Die gesin is noodsaaklik vir die modeme mens se soeke na vastigheid, geborgenheid en identiteit. Die oorspronklike verhouding tussen ouer en kind binne die kerngesin is onvervangbaar. Die vraag wat in die studie aan die orde kom is of die modeme gesin wel so 'n belangrike plek inneem in die huidige samelewing. Is die gevolg van al die probleme waarmee die moderne gesin le kampe het en die wisselvallige wereld waarin ons lewe nie juis dat die gesin se plek as veilige hawe al hoe meer bedreig word nie? Daar moet altyd in die bediening aan die gesin onthou word dat die gesin 'n ontwikkelende sisteem is. Daar moet veral by die behoeftes in die verskillende lewensfases aangesluit word. ln God se handeling met. die mens vind ons dat daar 'n baie noue verband is tussen die gesin en die verbond. Soos tewens die hele gemeente, is die gesin ook "'n koninklike priesterdom . .. . . . die eiendomsvolk van God". (1 Pet. 2:9) Die kerk staan voor die wonderlike uitdaging om in die tyd waar daar 'n besondere behoefte aan sosiale verhoudings bestaan, die behoefte te vul met iets wat God self gee, iets wat veel grater as sosiale vriendskap is... . . . koinonia! Des te meer die kerk se invloedsfeer in die samelewing krimp en mense nie meer aktief by die instituut inskakel nie, des te belangriker word die gesin. In die gesekulariseerde samelewing word die gesin die konkrete kontakpunt waarmee die kerk op die plaaslike vlak sy invloedsfeer binne mense se daaglikse leefmilieu kan laat geld. Die studie vra vir 'n andersoortige bediening waarin die behoeftes van die gesin aangespreek word en waar die gesin primer die fokus is. Dit moet 'n bediening aan die gesin en 'n bediening deur die gesin wees. Die gemeente moet gesinne leer en aan hulle demonstreer wat God se doe! met die gesin is. Die kerk is by uitstek in die posisie om die wye verskeidenheid van gesinstipes in die samelewing te kan bedien. Die kerk kan ook gesinne help om aanpassings te maak in 'n veranderende samelewing. 'n Gesinsbediening kan 'n uitstekende nuwe fokus word vir die missie van die kerk. / Researches on the family came to the conclusion that the family is irreplaceable in the socialising process of a person. The family is necessary for the modern persons need for stability, security and identity. The original relationship between a parent and child in the family is irreplaceable. The question which arises in this study is whether the modern family is so important in the current society. Is the result of all the problems which the family faces and the changeable world not that the family as secure harbour is in danger? In the ministry it must always be borne in mind that the family is a developing system. Special attention must be paid so that all the different phases of life are included. In God's involvement with man, we find that there is a very close relationship between the family and the sacrament. As is the entire church, so is the family " ...... priests of the King, ..... God's own people" (1 Pet. 2:19). In a time where there is an exceptional need for social relationships, the church is faced with a great challenge to fill this need with something that is from God, something far more fulfilling than social friendships .... Kononia. The further the churche's influence declines in a society and people withdraw from involvement within the institution, the more important the family becomes. In a secularized society the family becomes the concrete point of contact through which the church can, at local level, use its influence within peoples daily life environment. This study calls for another type of ministry in wt)ich the needs of the family can be addressed and where the family becomes the primary focus.· It must b~ a ministry to the family and through the family. The congregation must educate families as well as demonstrate God's purpose with the family. The church is pre-eminently in a position to serve the various types of families in society. The church is also able to help families to make adjustments in a changing society. A family ministry can become an excellent new point of focus for the mission of the church. / Philosophy, Practical and Systematic Theology / D.Th. (Practical Theolgy)

The aim of this study was to create awareness of the emotional needs of children diagnosed with ADHD. In order to reach the aim of this study, an initial literature study was executed to describe ADHD and the emotional needs of children. Semi-structured interviews and two projective techniques were used to conduct the empirical study. Valuable data was also collected from the biographical questionnaires completed by the parents. Based on the data collected and analysed, findings were made which were verified by means of a second literature study. This was followed by conclusions which served as the basis for recommendations that were made in the form of guidelines to the parents, with the aim to make the parents aware of the emotional needs of their children diagnosed with ADHD. These guidelines will be made available to the parents at a seminar that will be held on acceptance of this research. / Social Work / M.Diac. (Play Therapy)