Development Of Attitude Determination For Student Pico-Satellite INNOSAT.

Information of satellite’s attitude is very useful in autonomous satellite control system. For a small satellite particularly, attitude sensor cannot be installed in the satellite because of the limited weight and power consumption

DYNAMIC BEHAVIOUR OF PAPER HONEYCOMB SANDWICH PANELS

Low velocity impact tests have been conducted on paper honeycomb sandwich panels. Two panel thicknesses with span length of 100 mm are used; these are 35 mm and 41 mm, respectively. The dynamic behavior of each paper honeycomb thickness is investigated using two types of indentors: hemispherical and bar. The effect of indentor, and specimen length are studied. This includes the pattern of loaddisplacement curve collapse load and energy absorbed. It concludes that the dynamic collapse load on 41 mm thickness for hemispherical indentor increases by 5% compared with 35 mm. The impact energy absorbed for hemispherical indentor increases by 36%

On the security of digital signature protocol based on iterated function systems.

A common goal of cryptographic research is to design protocols that provide a confidential and authenticated transmission channel for messages over an insecure network. Hash functions are used within digital signature schemes to provide data integrity for cryptographic applications. In this paper, we take a closer look at the security and efficiency of the digital signature protocol based on fractal maps. This new system can be expected to have at least the same computational security against some known attacks. A Diffie-Hellman algorithm is used to improve the security of the proposed protocol by generating the number of iteration that is used to find the attractor of the iterated function system, which is used to calculate the public key and the signature. The proposed algorithm possesses sufficient security against some known attacks applicable on finite field cryptosystems. They are considered as time consuming to be involved in solving non-linear systems numerically over the defined infinite subfield

Deterministic and Recursive Approach in Attitude Determination for InnoSAT

Attitude determination system (ADS) was indispensable in attitude control of satellite. Especially for InnoSAT due to the limitation of budget, weight, and power, the attitude was determined using onboard position sensors. Previous research has successfully implemented the attitude determination using only Earth's magnetic field sensors for small attitude angle, but the approach produced quite big error for large attitude angle. This paper presents attitude determination for InnoSAT using combination of sun sensors and earth's magnetic field for large attitude angle. The attitude was determined using a deterministic (QUEST) and recursive (EKF) approach. A problem arises when using the sun sensors while the satellite experiencing eclipse. Consequently, the accuracy of both approaches was analyzed at eclipse and no eclipse conditions. The result shows that deterministic approach produced better accuracy at no eclipse but recursive approach produced better accuracy at eclipse. The strategy to apply the both approaches and eclipse conditions also discussed in this paper

Fractal attractor based digital signature

Fractal theories are applied to enhance the efficiency and performance of cryptosystem due to their inherent complexity and mathematical framework. A new digital signature scheme based on Iterated Function System (IFS) is proposed, which can reduce computation cost and increase security of the system. The properties of the proposed system are discussed in detail

Masyarakat Sivil Dan Demokratisasi Politik Di Malaysia: Satu Analisis Ringkas

This paper analyzes the democratization process in Malaysia by positing the role of civil society as the engine of change. The analysis in this paper differs from the views of previous scholars who argued that political protests against the government first emerged during Dr Mahathir's regime. In fact, this paper argues that the protests process started even before Malaysian independence. Although this process continues to take place, it has not brought about real democratization in Malaysia. This is because of the success of the ruling government in providing comfort and feeding the people resulting in difficulty for civil societies to convince the peoples of the need for political transformation. In this aspect, this paper discusses a new approach for political protests by civil society over abuse of power by government, that is through political protests 'from within' which is more effective in raising the people's consciousness toward political change. The paper ends with a conclusion that one of the distinguishing features of Malaysia politics that differs from other political regimes in the world is that political leaders in Malaysia never have to shed the blood of its citizens and this is the very reason that they are able to sustain their status quo until now

About fuzzy fixed point theorem in the generalized fuzzy fractal space.

The Banach fixed point theorem has applications in several branches of science. Many authors prove this theorem in different types of fuzzy metric spaces and fuzzy fractal spaces. The aim of this paper is to prove the Banach fixed point theorem in a new generalized space called multi fuzzy fractal space

Efficiency analysis for public key systems based on fractal functions.

In the last decade, dynamical systems were utilized to develop cryptosystems, which ushered the era of continuous value cryptography that transformed the practical region from finite field to real numbers. Approach: Taking the security threats and privacy issues into consideration, fractals functions were incorporated into public-key cryptosystem due to their complicated mathematical structure and deterministic nature that meet the cryptographic requirements. In this study we propose a new public key cryptosystem based on Iterated Function Systems (IFS). Results: In the proposed protocol, the attractor of the IFS is used to obtain public key from private one, which is then used with the attractor again to encrypt and decrypt the messages. By exchanging the generated public keys using one of the well known key exchange protocols, both parties can calculate a unique shared key. This is used as a number of iteration to generate the fractal attractor and mask the Hutchinson operator, so that, the known attacks will not work anymore. The algorithm is implemented and compared to the classical one, to verify its efficiency and security. We conclude that public key systems based on IFS transformation perform more efficiently than RSA cryptosystems in terms of key size and key space

The case of cholera preparedness, response and prevention in the SADC region: A need for proactive and multi-level communication and co-ordination

In this paper the authors seek to identify the most appropriate model for a regional co-ordination mechanism for cholera preparedness, response and prevention. The qualitative mixed-method data collection approach that was followed revealed the need for alternative solutions, including a socio-political understanding of cholera responses at different levels of scale and at different stages of an outbreak. Important areas that need to be understood include the multiplicity of actors and the complexity of their interaction, the importance of building local capacity, the need for varying responses at different levels of scale, the need for improved inter- and intra-country co-ordination and information exchange, the importance of cultural belief systems and the impact of the media on the response to cholera outbreaks. Ultimately, despite the proposed co-ordinating role that the Southern African Development Community (SADC) can play in a regional cholera response effort, the onus remains on states to build capacity at the local level and to capacitate local communities to drive response efforts semi-autonomously.Keywords: Cholera prevention, preparedness and response, socio-political understanding of cholera, socio-cultural understanding of cholera, transboundary disease, Southern African Development Community (SADC), choler

IFS on the multi-fuzzy fractal space.

The IFS is a scheme for describing and manipulating complex fractal attractors using simple mathematical models. More precisely, the most popular “fractal –based” algorithms for both representation and compression of computer images have involved some implementation of the method of Iterated Function Systems (IFS) on complete metric spaces. In this paper a new generalized space called Multi-Fuzzy Fractal Space was constructed. On these spases a distance function is defined, and its completeness is proved. The completeness property of this space ensures the existence of a fixed-point theorem for the family of continuous mappings. This theorem is the fundamental result on which the IFS methods are based and the fractals are built. The defined mappings are proved to satisfy some generalizations of the contraction condition