Fuzzy Adaptive Hysteresis of RSS for Handover Decision in V2V VANET

A communication technology which enables the information exchanges between vehicles to support intelligent transportation system is the characteristic of vehicular ad hoc network (VANET). The vast applications of VANET including transportation safety, traffic management, and passenger amenities are also followed by some technical challenges. The rapid topology changes and high nodes mobility are the main source of the challenges. One of the prominent challenges is the handover decision, especially in vehicle to vehicle (V2V) communication. In this paper, handover decision method for V2V VANET is proposed using fuzzy system. The proposed method adjusts the value of received signal strength (RSS) hysteresis adaptively using fuzzy system so that the proposed handover decision method is called fuzzy adaptive hysteresis (FAH). To adjust the value of hysteresis, fuzzy system utilizes RSS value, speed difference, and connected time as the input. Based on the simulation results, the proposed method can reduce handover rate as well as maintaining the higher value of signal to noise ratio (SNR) average

Channel sharing utility function of power control game in cognitive femtocell network

The use of sharing channel simultaneously has become the trend in telecommunication technology particularly in network with distributed users as the allocation of frequency spectrum becomes more crowded. The proposed power control method in cognitive femtocell network is based on game theory (commonly known as power control game, PCG). This method uses utility function formula as the goal of game theory for power strategy in power update process. Utility function formula of Proposed PCG includes channel sharing factor that aimed to accommodate the system requirement of channel sharing. The result showed that the implementation of channel factor is inversely proportional to the signal to noise and interference ratio (SINR) and transmit power, but proportional to utility function. In comparison of user transmit power and SINR with two other methods, can also be conclude that Proposed PCG was able to achieve SINR of 5.49 dB and above the SINR target 5 dB, while the Thalabani (TB) and Koskie-Gajic (KG) were only able to achieve respective SINR of 4.87 dB and 4.98 dB. It can be concluded that the Proposed PCG was better in achieving the SINR target. It means that the quality of service in this system can be fulfilled properly

Feasibility of Power Control for Multi-Channel User in Inter-Femtocell Network

The importance of power control feasibility is closely related to the direct implementation of the system, which is related to interference between users in the femtocell network and also related to the optimal use of power transmit that can create a long-lasting battery. Implementation of the feasibility of power control in this study is focused on the centralized femtocell network with a multi-channel user. The research method in this study is based on the use of feasible solution algorithms in power control by observing the output of power vector that should be valued non-negative, which means that it can be implemented. This result indicates that all of user can reach the specified target SINR. SINR users will increase when there are additional channels for user groups. The average power of user will also decrease while increasing the amount of provided channels. The greater number of users in a user group, the less value SINR can be obtaine

Inability to predict postpartum hemorrhage: insights from Egyptian intervention data

<p>Abstract</p> <p>Background</p> <p>Knowledge on how well we can predict primary postpartum hemorrhage (PPH) can help policy makers and health providers design current delivery protocols and PPH case management. The purpose of this paper is to identify risk factors and determine predictive probabilities of those risk factors for primary PPH among women expecting singleton vaginal deliveries in Egypt.</p> <p>Methods</p> <p>From a prospective cohort study, 2510 pregnant women were recruited over a six-month period in Egypt in 2004. PPH was defined as blood loss ≥ 500 ml. Measures of blood loss were made every 20 minutes for the first 4 hours after delivery using a calibrated under the buttocks drape. Using all variables available in the patients' charts, we divided them in ante-partum and intra-partum factors. We employed logistic regression to analyze socio-demographic, medical and past obstetric history, and labor and delivery outcomes as potential PPH risk factors. Post-model predicted probabilities were estimated using the identified risk factors.</p> <p>Results</p> <p>We found a total of 93 cases of primary PPH. In multivariate models, ante-partum hemoglobin, history of previous PPH, labor augmentation and prolonged labor were significantly associated with PPH. Post model probability estimates showed that even among women with three or more risk factors, PPH could only be predicted in 10% of the cases.</p> <p>Conclusions</p> <p>The predictive probability of ante-partum and intra-partum risk factors for PPH is very low. Prevention of PPH to all women is highly recommended.</p

Moth Flame Optimization for Weight Adjustment on Phased Array Antenna

Adaptive beamforming refers to a method to proceed a signal to improve strength and steer the main beam of smart antenna to the desired user against interferer. In a phased array antenna, the weight of each element is adapted with Weight Adjustment Moth Flame Optimization (WAMFO). The algorithm is based on Moth Flame Optimization (MFO) that is inspired by the moth making spiral move to the flame as the objective function. The objective function is to obtain the minimum difference between reference and incoming signal. The weighted sum will generate the highest power to the desired direction, and then the interferer will be set to null. The simulation resulted in a uniform linear array showing that weight adjustment with the algorithm proposed could achieve faster convergence than other metaheuristic schemes. WAMFO had the average SNR values improvement of 26 to 32 dB for 100 iterations in five different scenarios. © 2022 IEEE

The Blueprint of AWOS Implementation for Aviation Services at BMKG

Weather is very critical for aviation. Especially regarding safety in air transportation. Badan Meteorologi, Klimatologi, dan Geofisika (BMKG) in its duties and functions provides aviation weather information, conducts the latest weather observation activities for the needs of takeoff and landing at airports. The World Meteorological Organization (WMO) has targeted automation with a target achievement in 2017. But currently in conducting the latest weather observations, BMKG still uses conventional weather observation systems even though at some airports Automated Weather Observing Systems (AWOS) have been installed. The automated weather observing system is still not fully implemented yet. This study aims to create a blueprint for the implementation of automatic weather observations for aviation services within the BMKG. Guidelines for making blueprint use the Enterprise Architecture Planning (EAP) framework. EAP defines business and architectural needs related to data, applications, and technology needed to implement automation. The final results achieved are in the form of a blueprint for the implementation of automated weather observing system for aviation services within the BMKG which can be a guide for BMKG in achieving the vision related to aviation weather services

Performance Evaluation of LoRaWAN for Smart Shuttle Bus System Support in Campus Area

Improving the accessibility of public transportation can be achieved by using a tracking system. However, some of the current tracking system technologies use a high operational cost and power consumption wireless connectivity. The use of a tracking system based on the Internet of Things (IoT) can address those problems. This study aims to evaluate the performance of Long-Range Wide Area Network (LoRaWAN) for smart transportation (shuttle bus) system support in campus areas. The performance evaluation uses six different configurations of date rate, DRO -DR5. The test was performed by placing the LoRaWAN based GPS tracker based on the shuttle bus roof and measuring several performance parameters, including Signal to Nosie Rasio (SNR), Received Signal Strength Indication (RSSI), and packet loss. The analysis of the test results is presented in comparisons of the performance parameters values and heatmaps based on the SNR and RSSI values on the shuttle bus route. The results analysis showed a slight difference value on SNR, RSSI and packet loss when using data rate DRO - DR5. Based on the performance evaluation, the LoRaWAN is able to provide reliable communication since the average SNR value is over 0dB, average value of RSSI is over -100dBm, and the maximum packet loss value is under 3 for each data rate. © 2022 IEEE

A Novel Utility Function of Power Control Game in Multi-Channel Cognitive Femtocell Network

Importance of power control is associated with distributed user characteristics, which is self-organized and non-cooperative in multi-channel cognitive femtocell network. Power control on proposed PCG was based on the use of game theory method by generating the utility function that referred to the provision of solutions to the weakness of previous studies that was the inability to achieve the SINR target. The results showed that the proposed PCG was able to achieve the target SINR so that the quality of service can be fulfilled properly. This achievement has not been met by other methods (KG and TB methods). In addition, each of these three methods had nearly similar convergent rate, thus it can be concluded that the stability of these three methods were similar