18 research outputs found
Providing Complete Precision Timing Solution for Hospitals by GPS Time Synchronized with MCS
The time is very important in the life and hasa special significance for hospitals, Where is specially used inoperating rooms, Nurse Call System (NCS) , various medicaltests and many other medical services. Those importantthings are mainly to use Master Clock System (MCS) in thehospitals. In this paper we provided high precision time forhospitals by used Global Positioning System (GPS) timesynchronized with MCS. The time will get synchronizedfrom satellite via GPS according to the Time Zone. GPSreceivers can provide precise time, speed, and coursemeasurements. Westerstrand GPS unit uses a miniature 12-channel GPS will use in the system and its compact size andlow power consumption make it ideal for this application.The system consists of Master clock control unit, GPSreceiver with antenna and related accessories
Light database encryption design utilizing multicore processors for mobile devices
The confidentiality of data stored in embedded and handheld devices has become an urgent necessity more than ever before. Encryption of sensitive data is a well-known technique to preserve their confidentiality, however it comes with certain costs that can heavily impact the device processing resources. Utilizing multicore processors, which are equipped with current embedded devices, has brought a new era to enhance data confidentiality while maintaining suitable device performance. Encrypting the complete storage area, also known as Full Disk Encryption (FDE) can still be challenging, especially with newly emerging massive storage systems. Alternatively, since the most user sensitive data are residing inside persisting databases, it will be more efficient to focus on securing SQLite databases, through encryption, where SQLite is the most common RDBMS in handheld and embedded systems. This paper addresses the problem of ensuring data protection in embedded and mobile devices while maintaining suitable device performance by mitigating the impact of encryption. We presented here a proposed design for a parallel database encryption system, called SQLite-XTS. The proposed system encrypts data stored in databases transparently on-the-fly without the need for any user intervention. To maintain a proper device performance, the system takes advantage of the commodity multicore processors available with most embedded and mobile devices
Critical data-based incremental cooperative communication for wireless body area network
Wireless Body Area Networks (WBANs) are single-hop network systems, where sensors gather the body’s vital signs and send them directly to master nodes (MNs). The sensors are distributed in or on the body. Therefore, body posture, clothing, muscle movement, body temperature, and climatic conditions generally influence the quality of the wireless link between sensors and the destination. Hence, in some cases, single hop transmission (‘direct transmission’) is not sufficient to deliver the signals to the destination. Therefore, we propose an emergency-based cooperative communication protocol for WBAN, named Critical Data-based Incremental Cooperative Communication (CD-ICC), based on the IEEE 802.15.6 CSMA standard but assuming a lognormal shadowing channel model. In this paper, a complete study of a system model is inspected in the terms of the channel path loss, the successful transmission probability, and the outage probability. Then a mathematical model is derived for the proposed protocol, end-to-end delay, duty cycle, and average power consumption. A new back-off time is proposed within CD-ICC, which ensures the best relays cooperate in a distributed manner. The design objective of the CD-ICC is to reduce the end-to-end delay, the duty cycle, and the average power transmission. The simulation and numerical results presented here show that, under general conditions, CD-ICC can enhance network performance compared to direct transmission mode (DTM) IEEE 802.15.6 CSMA and benchmarking. To this end, we have shown that the power saving when using CD-ICC is 37.5% with respect to DTM IEEE 802.15.6 CSMA and 10% with respect to MI-ICC
Modified guidance law based on a sliding mode controller for a missile guidance system
U ovom radu se predlaže metoda modificiranog regulatora navođenja i upravljanja kliznim režimom u sustavu vođenja projektila (MGCSMC). Algoritam modificiranog regulatora kliznog režima (MSMC) koristi se kako bi projektil stigao do željene mete u vrlo kratkom vremenu. Meta uvijek izvodi oštre manevre kad joj se približava projektil. Ovim se pitanjem bavi navođenje i upravljanje (G&C) primjenjujući algoritam MSMC umjesto tradicionalne metode kao što je proporcionalna metoda navigacije (PN). Provedena je teorijska analiza kako bi se smanjila greška u određivanju udaljenosti i pojava podrhtavanja u SMC. Simulacija MGCSMC u usporedbi s PN metodom pokazuje poboljšanje od oko 80 %, 47 % i 20 % u odnosu na podrhtavanje, pogrešnu udaljenost i konačno vrijeme. Nadalje, za vrlo visoku metu, MGCSMC poboljšava ubrzanje i nagibni kut putanje leta projektila za približno 65 % te postiže točnost od 100 %, dok se PN metodom postiže točnost od samo 60 % pod istim uvjetima.mode controller (MSMC) algorithm is adopted to enable the missile to reach the desired target within a short period of time. The target always makes high manoeuvres when the missile is close to it. This issue has been treated in guidance and control (G&C) by using a MSMC instead of the traditional method such as proportional navigation method (PN).Theoretical analysis is conducted to reduce the miss-distance and chattering phenomenon in SMC. Simulation of MGCSMC compared with PN method shows an improvement of about 80 %, 47 % and 20 % for the chattering, miss-distance and finite time, respectively. Furthermore, for the high-altitude target, the MGCSMC improves the acceleration and flight angle of the missile by approximately 65 %, and achieves 100 % accuracy, whereas in PN method only 60 % accuracy is achieved under the same conditions
Enhancement of the duty cycle cooperative medium access control for wireless body area networks
This paper presents a novel energy-efficient and reliable connection to enhance the transmission of data over a shared medium for wireless body area networks (WBAN). We propose a novel protocol of two master nodes-based cooperative protocol. In the proposed protocol, two master nodes were considered, that is, the belt master node and the outer body master node. The master nodes work cooperatively to avoid the retransmission process by sensors due to fading and collision, reducing the bit error rate (BER), which results in a reduction of the duty cycle and average transmission power. In addition, we have also presented a mathematical model of the duty cycle with the proposed protocol for the WBAN. The results show that the proposed cooperative protocol reduced the BER by a factor of 4. The average transmission power is reduced by a factor of 0.21 and this shows the potential of the proposed technique to be used in future wearable wireless sensors and systems
Non-Cooperative Game Theory Approach for Cognitive Cooperative Communication in WBAN
To increase the Quality of Service (QoS) of wireless body area network, we need an effective data-rate delivering method, which capably forwarding the data over several path. For this reason, we proposed a non-cooperative game approach, based on utilizing a pricing-based spectrum leasing mechanism to transmit the data over several path based on non-cooperative game theory. The parameter price c is together determined by WBAN sensor and D2D users. Then, all selected D2D users used optimized powers that can fulfil the need of the WBSN users. Numerical results show the proposed approach improves the utility of WBSN users and their throughput
Reliable emergency data transmission using transmission mode selection in wireless body area network
The main differences between wireless body area network (WBAN) and wireless sensor network are the sensors in WBAN distributed on the human body; therefore, body posture, clothing, muscle movement, body temperature, and climatic conditions generally influence the links between sensors and destination. Second, data gathered by the sensors are related to human life; therefore, it is important to make sure that the gathered data should be delivered to destination efficiently. Hence, in some cases, single-hop transmission or direct transmission mode (DTM) is not sufficient to deliver the data to the destination. In this paper, we proposed an emergency-based cooperative communication protocol for WBAN, named as Emergency Data Transmission using Transmission Mode Selection (ED-TMS) protocol based on the IEEE 802.15.6 CSMA. First, a complete study of a system model is inspected in terms of channel path loss, successful transmission probability, and the outage probability. Second, a mathematical model of the proposed protocol, end-to-end delay, and throughput with relay selection (RS) is derived. Third, RS is utilized along with ED-TMS, which makes only the best relay participate in cooperation in a distributed manner. The design objective of the ED-TMS is to reduce end-to-end delay and enhance the throughput of direct transmission and traditional cooperative communication. The simulation and numerical results show that the ED-TMS can enhance network performance under general conditions compared to DTM IEEE 802.15.6 CSMA and benchmark. The end-to-end delay reductions of ED-TMS with RS with respect to DTM, mutual information incremental cooperative communication, and ED-TMS without RS are 24.5%, 28%, and 30%, respectively
Optimization of reaction parameters of esterification on the synthesis of palm oil-based alkyds using response surface methods
In this research, polyalkyd resins were prepared from palm oil by polycondensation reaction. A two-step method viz., alcoholysis and esterification were conducted to synthesize polyalkyd resins. Response surface methodology was used to optimize the reaction parameters for esterification like reaction temperature, reaction time, catalyst concentration, acid anhydride to mono-glyceride ratio and agitation speed. The optimum condition was used to prepare various types of polyalkyds using different types of acid anhydrides such as, maleic anhydride, succinic anhydride, phthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride and cis-1,2-cyclohexanedicarboxylic anhydride. Result analyses through RSM revealed a desirability of 0.985 for the reaction time of 88.64 min. Moreover, 91.5% fractional conversion was achieved actually, which is close to the predicted value. The analysis revealed that 3,4,5,6-tetrahydophthalic anhydride-based resin showed improved resinous property than others due to the high degree of crosslinking