This paper proposes a novel approximation for a Spatial Time Division Multiple Access (STDMA) link-scheduling algorithm based on geometrical node exploitation to improve spatial reuse performance. The geometrical location of nodes was exploited in order to reduce computational complexity and to achieve higher accuracy in transmission to satisfy the Signal to Interference and Noise Ratio (SINR) requirement. The process of SINR global checking is a main constraint in the SINR based interference model but is reduced through geometrical partition and interference approximations based on geometrical node locations. Simulation results show that the proposed algorithm increases the spatial reuse performance in comparison to the greedy physical interference model in similar scenarios. The model utilizing geometrical partition exhibits lower complexity compared to the pure physical interference model that includes SINR global checking.

The crucial issue in the design of resource allocation algorithms for wireless mesh network is computational complexity. A high capacity algorithm with low computational complexity is desired, especially for dynamic topology adaptation in mobile mesh networks and also for the issue of low energy consumption. This paper proposes a new approach in the designing of a low complexity spatial time division multiple access link scheduling algorithm for wireless mesh network. In this paper, link scheduling is considered as a decision-making problem. This approach is contrary to physical interference model that requires SINR evaluation in global network. We propose the mesh coverage probability as a new performance metric in the design of mesh link scheduling algorithm. Based on this approach, we provide the tradeoff between spatial reuse and mesh coverage probability, which can be used as a benchmark in the design of scheduling algorithms for wireless mesh network.

In this paper, we provide the capacity, quality, and coverage trade-off in spatial time division multiple access (STDMA) wireless mesh network. To analyze the tradeoff, we propose the new method that the. STDMA link scheduling decision is done by relaxing SINR requirement and link scheduling is considered as a decision process. We propose the mesh coverage probability and SINR margin as a new performance metrics that can be used for of link scheduling algorithm benchmarking. Based on this approach, the trade-off between capacity i.e., spatial reuse, quality i.e., margin SINR, and mesh coverage probability can be derived, which are those three parameters very important in general Wireless network characterization.

The algorithm to allocate mesh active link to radio resource timeslot in wireless mesh network (WMN) is investigated. This paper proposes the novel method to allocate multiple links in one timeslot for improving the wireless mesh network throughput via spatial time division multiple access (STDMA) protocol. The throughput improvement is obtained by modifying greedy based algorithm that is widely known as a low complexity algorithm. We propose and investigate new parameters in the greedy based algorithm that can be used as scheduling control parameters, i.e. interference weight, scheduling weight, and the sum of link’s degree. Simulation results indicate that this approximation increases network performance in throughput and length of scheduling performance closed to the upper bound performance that is achieved by the algorithm that uses the physical interference model.

Currently, one of the major security issues in wireless environment is the intrusion coming from an unknown and unauthorized wireless access points. This access points could expose any sensitive information transmitted over the network. Until now the Intrusion Detection System (IDS) on Wireless network environment is still being developed because the necessary of its architectural design and IDS detection techniques need high levels of optimization in accommodating unique characteristics. IDS on Wireless network must have an adaptive nature and meet the scalability aspects in a distributed wireless network, as well as having a high accuracy detection with low false positive rate by taking into account the resource constraints on wireless networks. Furthermore, the convenience of the user in accessing network wirelessly could face the security risks against the intrusion of the possible Unauthorized Access Point, which is not legitimized and registered on a network. A more proactive detection system to protect this kind of intrusion has become an important part in the development of Intrusion Detection System. In this research, the mechanism of detecting the presence of Unauthorized Access Point is developed and the accuracy rate for identifying and detecting the presence of this kind of Access Point is also analyzed. During the test, it is showed that the accuracy of detection system reaches about 100% on idle traffic conditions, then declined to around 90%-70% in medium to low traffic conditions.

Red-light running problem has been recognized as a significant safety problem in Indonesia as well as throughout the world. This is a frequent and highly dangerous driving act. Reducing this risk behavior depends on understanding its prevalence, as well as the drivers involved. However, it should also improve the infrastructure system in order to be an intelligent system. In this study, modeling and simulations are made to measure the speed of each vehicle that will pass through the intersection to predict the possibility of vehicles violating traffic lights. The detection of vehicle IDs used discrete tracking algorithm base on region. The result showed that the position data and time detection sensor used successfully to determine the average speed, the distance from the intersection and acceleration of the movement of vehicles. From the predicted results, a vehicle violates traffic lights reached 82.68%.

 Abstract—In this paper will be described integration of Discrete Cosine Transform (DCT) process and quantization in video data compression algorithm. The integration is done in order to improve time and compression ratio. The method is employed by inserting quantization process in the DCT function, as well as for the decompression process. It can be done since the orthonomality property of the prior DCT function is still valid, algebraically. Result obtained in this paper is related with the first aim, that is, a better compression time. It is obtained based on mathematical and algorithm analyses done, that the integration of the two processes can improve to a better time complexity.

This paper discusses the characteristics of Transmission Opportunity Hybrid Coordination Function Controlled Channel Access (TXOP-HCCA) for real-time application. This works presents the evaluation of TXOP duration limits based on IEEE 802.11e standard, and IEEE 802.11g for physical layer of ERP-OFDM and DSSS-OFDM technologies. HCCA 802.11e stated that superframe consists of Contention Free Period (CFP) and Contention Period (CP). In this work we utilized the CFP to transmit TXOP with different traffic rates for real time packet transmission. This TXOP consists of the packets with different payload and packet numbers. We optimize the payload to achieve maximum local TXOP. We present the detailed analysis of characteristics of TXOP-HCCA which is based on detailed logical explanation of tracing the superframe values. The evaluation stage is conducted in uniform traffic rate. Subsequently we evaluate the combined traffic rates by varying the packet’s payload and TXOP. Knapsack optimization method has been used to achieve the optimum TXOP in combined traffic rate. The simulation result shows that the optimum CFP utilization value is 88.12 %. .

Recent developments in the various researches suggests that the mechanisms and algorithms in resource allocation is widely seen as a major new opportunity to improve the wireless networks performance. In the wireless mesh network which is now seen as a potential topology candidate in future networks, spatial reuse exploitation in scheduling is one solution to extend network capacity. This paper provides the evaluation of the performance of the scheduling algorithm in a mesh network based on time division multiple access method by spatial reuse exploitation, in comparison with another basic time division multiple access method. This paper was used as a basis to examine the possibility of developing a wireless mesh network performance through the mechanism of resource allocation, in WiMAX case.

The design of an intelligent controller based on fuzzy TS model for a pressure process rig is presented. The proposed controller consists of a fuzzy TS model, a feedback fuzzy TS model, and a low pass filter combined in an internal model control structure. The identification of the fuzzy TS model uses fuzzy clustering technique to mimic the nonlinearity characteristic of the process. Instead of least-squares algorithm, the instrumental variable method is used to estimate the consequent parameters of the fuzzy TS model in order to avoid inconsistency problem. The identified model is validated with the performance indicators variance-accounted-for and root mean square. By using the technique of inverse fuzzy model analytically, the feedback fuzzy controller is designed based on the identified fuzzy TS model. The performance of the proposed controller is verified through experiments at various operating points.

In this paper, we elaborate a new delay calculation on IEEE 802.11g-over-Fiber networks theoretically. It is found that delays generated by optical fiber and optical transceiver are more dominant than the air propagation. In this case, by inserting optical transceiver delay made the fiber length difference of 100 m.

A dynamic mathematical model for a new structure of precision air conditioning (PAC) has been developed. The proposed PAC uses an additional secondary condenser for relative humidity regulation compared to a basic refrigeration system. The work mechanism for this system and a vapour-compression cycle process of the system are illustrated using psychrometric chart and pressure-enthalpy diagram. A non-linear system model is derived based on the conservation of mass and energy balance principles and then linearized at steady state operating point for developing a 8th-order state space model suited for multivariable controller design. The quality of linearized model is analyzed in terms of transient response, controllability, observability, and interaction between input-output variables. The developed model is verified through simulation showing its ability for imitating the nonlinear behavior and the interaction of input-output variables.

Wireless network characteristic is quite different from wired networks. It is more vulnerable to security disturbances. Furthermore, the convenience of the user in accessing network wirelessly could face the security risks against the intrusion of the possible Illegal Access Point (IAP), which is not legitimized and registered on a network. One of the serious problems is relating to the users who are not so aware and knowledgeable on how to to protect themselves.. A more proactive detection system to protect this kind of intrusion has become an important part in the development of Intrusion Detection System. This research aim is to develop a web based tool of proactive intrusion detection system to cover the weaknesses that exist in conventional Intrusion Detection System, especially in terms of protecting from the presence of illegal access point device. Using Proactive Protection tool with Web-based Applications on the server side could be benefit for the users to easily detect the presence of IAP without involving a network administrator.

The algorithm's improvement is started by compression process which is discussed in this paper, and continued by encryption process using finite field Z23-based bit stream. In this paper will be described integration of Discrete Cosine Transform (DCT) process and quantization in video data compression algorithm. The integration is done in order to improve time and compression ratio. The method is employed by inserting quantization process in the DCT function, as well as for the decompression process. It can be done since the orthonomality property of the prior DCT function is still valid, algebraically. The use of finite field Z23 as the basis of bit stream encryption process with chaotic cipher. Construction of finite field Z23 is based on finite field Z2, algebraic concept employed in cryptography. Finite field Z23 has 8 elements whereas Z2 has 2 elements. Therefore more combination of bit stream composition pattern can be achieved and robustness against known-plaintext attack is expected. Result obtained in this paper is related with the first aim, that is, a better compression time. It is obtained based on mathematical and algorithm analyses done, that the integration of the two processes can improve to a better time complexity.

— Nowadays wireless technology plays an important role in public and personal communication. However, the growth of wireless networking has confused the traditional boundaries between trusted and untrusted networks. Wireless networks are subject to a variety of threats and attacks at present. An attacker has the ability to listen to all network traffic which becoming a potential intrusion. Intrusion of any kind may lead to a chaotic condition. In addition, improperly configured access points also contribute the risk to wireless network. To overcome this issue, a security solution that includes an intrusion detection and prevention system need to be implemented. In this paper, first the security drawbacks of wireless network will be analyzed then investigate the characteristics and also the limitations on current wireless intrusion detection and prevention system. Finally, the requirement of next wireless intrusion prevention system will be identified including some key issues which should be focused on in the future to overcomes those limitations.

The tracking of vehicles using RFID was developed consider three major problems, i.e. traffic signal timing, congestion on road and theft of vehicles. This paper describes an algorithm for predicting the speed of traffic light violators. The novel algorithm is implemented in the form of a simulation program. The traffic light system is equipped RFID reader as the main tool for identifying the vehicle’s RFID tags. In the simulation, the vehicle’s ID is generated using a random number generation. The distribution of the vehicle’s numbers is uniform and the expected number of vehicles violated the traffic light is not mor e than 3 % of the total number generated. The timing accuracy for speed traffic lights violator is 100 milli seconds . From the simulation conducted, the algorithm has performed as expected. It is able to predict the speed of traffic light violators ranging from 5 km/h up to 80 km/h in real-time.

SIMPLE: System Automatic Essay Assessment for Indonesian Language Subject Examination. Evaluation of study of a student is a very important aspect of an educational process. Evaluation is aimed at measuring the level of student understanding of the given lecture materials. Measuring student understanding of the course material, using essay-type exam, is generally used as the evaluation tool. In this essay-type exam, the student has to answer questions using sentences, whereby choices of possible answers are not indicated. The student has to answer the questions with his/her sentences. The answers may vary, since it reflects the student’s best thoughts of the materials. One of the weaknesses of essay-type exam is the difficulty to grade the answers and it tends to be time consuming. Currently, automatic grading systems that may speed up the grading process, are being developed in many research institutions. The method used to grade, varies form one system to another, and one of the popular system is the Latent Semantic Analysis (LSA). LSA is a method of grading essay by extracting words and representing the sentence in the form of mathematical or statistical formulation, from a text with a relatively large number of words. The grade of the essay is determined, by matching the important words to a group of words prepared by the human rater. This paper describes an effort to developed LSA, enhanced with word weighting, word order and the word synonym to improve the accuracy of grading. This system is called SIMPLE. SIMPLE is used to grade answers using bahasa Indonesia. The exam is carried out on-line through the Web. From the experiments conducted, for small classes, the conformity of grade compared to the grade of human rater lies between 69.80 % – 94.64 %, and for medium size classes the conformity lies between 77.18 % - 98.42 % with the human rater. These results are roughly proportional with the result of LSA system, which grade essay given in English.

This paper elaborates the performance analysis of a unicast network when two protocols, SCTP (Stream Control Transmission Protocol) and TCP (Transmission Control Protocol) coexist in the network. These two protocols are tested using File Transfer Protocol (FTP) and Constant Bit Rate (CBR) based traffic. From the simulations, it could be concluded that SCTP could achieve better throughput compared to TCP in both FTP and CBR based traffic, with sufficiently high fairness index of both intrafairness and interfairness. The increase of simulation time yields to the increase and relatively stable network performance. The increase of the number of sessions of small bandwidth applications resulted in the increase of troughput and link utilization. The simulations show that implementation of SCTP and TCP in a unicast network generally could be done without having to degrade the network performance, with relatively high fairness index, over 0.85 for various traffic variations.

Implementing web data extraction means we can directly extract data from various web pages, where they mostly formed in an unstructured HTML format, into a new structured format such as XML or XHTML. In this paper we review the implementation of web data extraction and stages in making a Mashup. We implement web data extraction by visually extract targeted data from data sources (web pages). Afterward, we combined web data extraction with the stages of making a Mashup, e.g. data retrieval, data source modeling, data cleaning/ filtering, data integration and data visualization. Problems arise in querying data sources due to unstructured contents of web pages (HTML), we cannot directly extract data into a new structured form. To address this problem, we propose a system, called Xtractorz, that can perform web data extraction in a Mashup format. We provide a fully visual and interactive user interface with new technique and approach using PHP and AJAX as the programming languages, and MySQL as the Data Repository. Furthermore, Xtractorz enables the user to conduct their job without the need to write a script or program or even without any knowledge of computer programming. The test results shows that Xtractorz requires less number of steps in making a Mashup compared with RoboMaker and Karma.