Agonistic behavior of captive saltwater crocodile, crocodylus porosus in Kota Tinggi, Johor

Agonistic behavior in Crocodylus porosus is well known in the wild, but the available data regarding this behavior among the captive individuals especially in a farm setting is rather limited. Studying the aggressive behavior of C. porosus in captivity is important because the data obtained may contribute for conservation and the safety for handlers and visitors. Thus, this study focuses on C. porosus in captivity to describe systematically the agonistic behaviour of C. porosus in relation to feeding time, daytime or night and density per pool. This study was carried out for 35 days in two different ponds. The data was analysed using Pearson’s chi-square analysis to see the relationship between categorical factors. The study shows that C. porosus was more aggressive during daylight, feeding time and non-feeding time in breeding enclosure (Pond C, stock density =0.0369 crocodiles/m2) as compared to non-breeding pond (Pond B, stock density =0.3317 crocodiles/m2) where it is only aggressive during the nighttime. Pond C shows the higher domination in the value of aggression in feeding and non-feeding time where it is related to its function as breeding ground. Chi-square analysis shows that there is no significant difference between ponds (p=0.47, χ2= 2.541, df= 3), thus, there is no relationship between categorical factors. The aggressive behaviour of C. porosus is important for the farm management to evaluate the risk in future for the translocation process and conservation of C. porosus generally

Study mass transfer of Cd, Hg, As, DDT and chlordane through adsorption onto granular activated carbon

The kinetic theory of liquid indicates that diffusion coefficient for the dilute liquid at ordinary pressure is essentially independent of mixture composition. Mass transfer is important in separation and adsorption process. However, diffusion may also be caused by other features. Because of the complex nature of mass diffusion, the diffusion coefficients are usually determined experimentally. The mass transfer resistance controls the kinetic adsorption rate, but there is only limited understanding of the adsorption of a solute onto porous material from surface water. Thus, this study was conducted to further enhance the understanding of the mass transfer and adsorption processes of micropollutants. The objectives of this study are to analyze the difference, examine the adsoprtion diffusion of mass transfer and evaluate the variation of total, internal and external mass transfer. This study also used the transformed equation to analyze the rate of adsorption during adsorption process onto different GACs. Five (5) micropollutants namely Hg, Cd, As, DDT and chlordane have been chosen to be adsorbed onto three (3) granular activated carbon which are SIG (shell industrial grade), SAG (shell analytical grade) and BAG (bitumen analytical grade). The micropollutants (Hg, Cd, As, DDT and chlordane) were prepared using standard stock solution in deionized water. Adsorption of pollutants onto SIG, SAG, and BAG were started at different percentages of outflow. Although the samples were taken at the same time, the outcome showed that a significant competition between adsorbates and adsorbents. From the analysis, SIG and SAG displayed excellent performance in adsorbing inorganic micropollutants while BAG for organic micropollutants. Before adsorption takes place, the morphology of the SAG indicated pore abundance compared to SIG and BAG. BAG pores are more structured than SIG and SAG. After adsorption occurs, more of the organic micropollutants are being adsorbed onto BAG and SAG. Meanwhile, SIG proved to be the best adsorbent for inorganic micropollutants. It takes 72 hours for Hg vi and As to saturate SIG whilst Cd take a longer time of 80 hours. SAG was also a good adsorbent for organic elements, with DDT taking 52 hours and chlordane taking 48 hours to be adsorbed. The [KLa]f value for the adsorption of Hg onto SIG was significant and the [KLa]d value for the adsorption of Hg onto SIG was higher onto SAG and BAG. The value of [KLa]f for SIG at 6% outflow was 0.6862 h-1, with values of [KLa]d at -0.4142 h-1 and [KLa]g at 0.2721 h-1, while for the adsorption of Cd it was shown that the [KLa]f values for the adsorption of Cd onto BAG was the most significant and the [KLa]d values for the adsorption of Cd onto SIG was higher than SAG and BAG at 2% outflow, with values of 0.7044 h-1, [KLa]d at -0.3687 h-1, and [KLa]g at 0.3356 h-1. In contrast, for As the [KLa]f for the adsorption of As onto BAG at 4% outflow was 0.6722 h-1 and [KLa]g was 0.3103 h-1. For DDT, the [KLa]f value of DDT for BAG at 0.5% outflow was 1.6662 h-1, [KLa]d was -1.2702 h-1 and [KLa]g was 0.3959 h-1. In the case of DDT, the value of [KLa]f for the adsorption of chlordane onto BAG at 2% outflow was 0.7330 h-1 and [KLa]d was started to activate the adsorption -0.5567 h-1. [KLa]g at 2% outflow was 0.1763 h-1. From these values we can conclude that for the adsorption of inorganic substances, SIG proved to be the best, while for organic substances BAG is the best adsorbent

Survey and Benchmark of Block Ciphers for Wireless Sensor Networks

Cryptographic algorithms play an important role in the security architecture of wireless sensor networks (WSNs). Choosing the most storage- and energy-efficient block cipher is essential, due to the facts that these networks are meant to operate without human intervention for a long period of time with little energy supply, and that available storage is scarce on these sensor nodes. However, to our knowledge, no systematic work has been done in this area so far.We construct an evaluation framework in which we first identify the candidates of block ciphers suitable for WSNs, based on existing literature and authoritative recommendations. For evaluating and assessing these candidates, we not only consider the security properties but also the storage- and energy-efficiency of the candidates. Finally, based on the evaluation results, we select the most suitable ciphers for WSNs, namely Skipjack, MISTY1, and Rijndael, depending on the combination of available memory and required security (energy efficiency being implicit). In terms of operation mode, we recommend Output Feedback Mode for pairwise links but Cipher Block Chaining for group communications

Supervisory control for conventional unitary air conditioning system

The Supervisory control for conventional unitary air conditioning system is conceptually designed based on Programmable Logic Control (PLC) system. The advantage of PLC system is that it allows online monitoring continually and updates or modification can be performed interactively. This supervisory mode is applied to the conventional unitary air conditioner to avoid the frequent interruption or adjustment of the fan speed or temperature set point by users normal practice which has contributed to the surge of energy consumption due to the frequent on/off of the compressor. Three experiments have been performed at different control methods to simulate user’s daily practice. The first control method is the Variable Set point with high speed fan, the second control method is the Fixed Set point with high speed fan and the third control method is a Supervisory Control; a fixed set point with variable fan speed. The experiments have been conducted for eight (8) hours and the statistic data of accumulated energy consumption based on one unitary air conditioner with capacity of 1 Horse Power are acquired and sampled at the time interval of 30 minutes for the analysis. From these experiments, the supervisory control has consumed 4.2 kWh per day which is 82.35% compared to normal consumption of 5.1 kWh. This result translated into 0.9 kWh or 17.65% of total energy saving per day. The consistency of the air compressor operation in this control method has become a major factor in achieving indoor temperature steadiness whilst improving the energy savings

AES Key Agility Issues in High-Speed IPsec Implementations

Some high-speed IPsec hardware systems need to support many thousands of security associations. The cost of switching among different encryption keys can dramatically affect throughput, particularly for the very common case of small packets. Three of the AES finalists (Rijndael, Serpent, and Twofish) provide very high key agility, as is required for such applications. The other two candidates (MARS, RC6) exhibit low key agility and may not be appropriate for use in such equipment

Analysis of Advanced Encryption Standards

The Advanced Encryption Standard (AES),the block cipher ratified as a standard by National Instituteof Standards and Technology of the United States (NIST), waschosen using a process markedly more open and transparentthan its predecessor, the aging Data Encryption Standard(DES).Fifteen algorithm were submitted as to NIST in 1998 ,NIST choose five finalist.NIST primary selection criteria are security, performance,and flexibility. This paper enlightens the last two criteria. Inthis paper we have discussed software performance of five AESfinalist.The paper specifically compares performance of the fiveAES finalist on a verity of common software platform: 32-bitCPU( both large and smaller microprocessors, smart cards,embedded microprocessors) and high end 64-bits CPUs

OPTIMIZATION OF TWO FISH ENCRYPTION ALGORITHM ON FPGA

The demand for efficient and secure ciphers has given rise to a new generation of block ciphers capable of providing increased protection at lower cost. Among these new algorithms is Twofish. Twofish is a promising 128-bit block which was one of the 5 finalists in the National Institute of Standards and Technology organized competition as the Advanced Encryption Standard. The aim of the competition was to find a suitable candidate to replace DES at the core of many encryption systems worldwide. Twofish can work with variable key lengths: 128, 192 or 256 bits. In this report, only a version of 128-bit key length was discussed. Twofish has 6 main building blocks; Feistel Networks, whitening, S-boxes, MDS Matrices, Pseudo Hadamard Transforms and Key Schedule. Twofish is a 16 round Feistel network with a bijective F function, which corresponds to 8 cycles. The whitening technique employed substantially increases the difficulty of keysearch attacks against the remainder of the cipher. Twofish uses 4 different, bijective, key-dependent, 8-by-8 bit Sboxes. Twofish uses a single 4 by 4 MDS matrix over GF (28).This is one of the 2 main diffusion elements of Two fish. There is also Reed-Solomon code with the MDS property used in the key schedule; this doesn't add diffusion to the cipher but does add diffusion to the key schedule.) Besides that, Twofish also uses a 32 bit Pseudo Hadamard Transform to mix the outputs from its 2 parallel 32-bit g functions. Finally, Twofish needs a lot of key material, and has complicated key schedule. To facilitate analysis, the key schedule uses the same primitives as the round function. Except for 2 additional rotations, each pair of expanded key words is constructed by applying the Twofish round function (with key-dependent). For this project, 2 different optimized designs were implemented. The first design (Design I) was implemented with minimum hardware resources usage, using a single F -Function (modified) and was optimized with reasonable latency, throughput and throughput per gate. As for the second design (Design 2) was implemented with reasonably minimum hardware resources using 4 units of F-Function(modified) of Design I, minimum hardware resources usage, very small latency, very high throughput and very high throughput per gate. Furthermore, both Design I and Design 2 were implemented with zero keying and function as encryptor/decryptor. Both Design I and Design 2 were written using VHDL, simulated using ALDEC, synthesized using XILINX Synthesizing Tools, implemented using XILINX ISE6.2i implementation tools and download onto the Spartan 2 FPGA board using BEDLOAD utility program. As a conclusion this Final Year Project is quite successful because all the objectives have been met successfull