Acute myocardial infarction is a leading cause of cardiogenic shock and mortality. The aim of current study is to identify factors and develop machine learning models that predicts in-hospital mortality of ST-segment elevation myocardial infarction (STEMI) patients in South-East Asian population. This is a single center, retrospective study, from patients presenedt to the emergency room at Kaohsiung Chang Gung Memorial Hospital, Taiwan. The study included non-trauma adults (≥20 years of age) who were diagnosed with acute STEMI. A total of 1567 patients who met the inclusion criteria were enrolled. The area under the receiver operating characteristic curve was 0.839 in logistic regression (LR) and 0.825 in random forest (RF). The accuracy was 0.821 in LR and 0.812 in RF. The sensitivity and specificity were 0.883 and 0.815 in LR, and 0.875 and 0.806 in RF. In conclusion, the predictive models developed using LR and RF algorithms can be used to predict the risk of in-hospital death for STEMI patients.

Sepsis is among the most common conditions requiring emergency hospitalization. The early and accurate identification of sepsis patients with a high risk of in-hospital adverse events can aid physicians in making optimal clinical decisions. This study aimed to develop an explainable neural network model to predict adverse events during hospital admission in patients with suspected sepsis. Patient data were collected from a single medical center in Taiwan for the period of 2018–2020. The adverse events considered during hospital admission were cardiac arrest, respiratory failure requiring mechanical ventilation, and transfer to intensive care unit during admission. This study included 9398 patients in the analysis, with 6794 and 2603 patients in the development and validation sets, respectively. The proposed model could predict adverse events with an area under the receiver operating curve of 0.88 and 0.85 in the development and validation sets, respectively. Of the 2603 patients in the test set, 523 (20.1%) were classified as having adverse events during hospital admission. Of these patients, 104 eventually experienced adverse events. Thus, the model can predict adverse events with good performance and therefore, can be regarded as a gatekeeper before patients with sepsis are admitted to the general ward.

Abstract During the past decades, mobile communication is in the vigorous development, where thecell planning problem(CPP) is one of impressive research issues. CPP has been proved to be NP‐Complete, and many works develop intelligent heuristic search strategies to solve it. Among many factors to affect the cell planning, the major one is the signaling cost, where the location management is critical to the cost. In this paper, we focus on how to tackle CPP such that the signaling cost can be minimized. We adopt a meta‐heuristic iterative search algorithm, Tabu Search (TS), to deal with the cell planning issue for the base station and propose novel designs to improve the TS capability, including initialization and neighbor swap strategy. The simulation results reveal that our TS outperforms traditional TS, genetic algorithms, and several previous works in CPP. Copyright © 2014 John Wiley & Sons, Ltd.

This paper describes the instructions of implementing IP protocol over DVB based network and makes the upper applications which utilize socket for IP data stream transmitting can be adopted on it seamlessly without any further modification. The main idea is carrying the IP packets through the modified virtual DVB networks interface by using the IP forwarding function built in Linux. Thus we can connect several LANs by using DVB devices and makes them as a backbone network. We believe that IP over DBV network will be a good option for digital contents broadcasting and IP data broadcasting because of the less modification to established system and the larger amount of the adoptable scenarios.

BACKGROUND: A classical problem in studying genome rearrangements is understanding the series of rearrangement events involved in transforming one genome into another in accordance with the parsimonious principle when two genomes with the same set of genes differ in gene order. The most studied event is the reversal, but an increasing number of reports have considered reversals along with other genome rearrangement events. Some recent studies have investigated the use of reversals and block-interchanges simultaneously with a weight proportion of 1:2. However, there has been less progress towards exploring additional combinations of weights. RESULTS: In this paper, we present several approaches to examine genome rearrangement problems by considering reversals and block-interchanges together using various weight assignments. An exact algorithm for the weight proportion of 1:2 is developed, and then, its idea is extended to design approximation algorithms for other weight assignments. The results of our simulations suggest that the performance of our approximation algorithm is superior to its theoretical expectation. CONCLUSION: If the weight of reversals is no more than that of block-interchanges, our algorithm provides an acceptable solution for the transformation of two permutations. Nevertheless whether there are more tractable results for studying the two events remains open.

As extensions in the emerging 802.11e for quality-of-service provisioning, burst transmission and the acknowledgment aggregation are the two important operations to improve the channel efficiency of IEEE 802.11-based wireless local area networks (WLANs). However, only a few works have been done on these operations, and usually assumed the networks to be operated under saturated traffic conditions and error-free channels. In practice, the assumptions may not be valid because real-time traffic with proper rate control will not saturate the networks and the channel is generally error-prone. Thus, the authors consider two new methods resulted from these operations and analyse their performance under unsaturated and error-prone WLANs, with a Markov chain model. The results show that the new methods generally have better throughput than the conventional IEEE 802.11 medium access control (MAC) in the WLANs.

The conventional medium access control (MAC) protocols assume that only one packet can be received at a given time. However, with the advent of spread spectrum, antenna arrays or sophisticated signal processing techniques, it is possible to achieve multipacket reception (MPR) in wireless communication networks. A distributed splitting-tree-based MAC protocol that can exploit the MPR capability in the networks is proposed. For the MPR MAC protocol, a closed-form expression of the system throughput is derived based on a Markov chain model. The experimental results show that the MPR protocol can considerably increase the spectrum efficiency compared with the splitting-tree algorithm with its conventional collision resolution method.

This paper focuses on the design and performance evaluation of a p-persistent transmission control protocol that can enhance the IEEE 802.11 DCF MAC, called P-IEEE 802.11 DCF. Unlike the so-called p-persistent IEEE 802.11, which is a variant of p-persistent CSMA and is not compliant with IEEE 802.11 DCF control scheme, our proposed protocol truly exploits the p-persistent transmission over the standard IEEE 802.11 MAC scheme. In WLANs, our protocol can greatly enhance the throughput by setting the optimal transmission probability in each back-off stage in DCF according to the throughput calculation results. When the number of active nodes varies, an intelligent scheme can adaptively adjust its transmission probability to achieve the maximal throughput during the run time. The key characteristics of our protocol are its simplicity, in compliance with the standard IEEE 802.11, complete distribution, and no requirement of handshaking extra messages among network hosts. Analysis and simulation results show the effectiveness of the p-persistent protocol in achieving the maximal throughput, and in improving the frame delay and short-term fairness.

In this paper, we introduce and analyze a new congestion control approach for multimedia streaming, called TMRC (Time-based Model TCP-Friendly Rate Control). TMRC is a time-based end-to-end congestion control mechanism, which uses a model to estimate sending rate and assures the fairness against competing flows. With our mechanism, the sender can explicitly adjust its sending rate as a function of the measured rate reported by the correspond receiver. In long term, TMRC acts as a TCP-friendly flow with the same throughput as other flows while in short term it performs more stable in its sending rate. This makes our mechanism suitable for real-time multimedia streaming. At last, we compare TMRC to other TCP-friendly rate control mechanism, such as TFRC.

The conventional clustering method has the unique potential to be the framework for power-conserving ad hoc networks. In this environment, studies on energy-efficient strategies, such as sleeping mode and redirection, have been reported, and, recently, some have even been adopted by standards like Bluetooth and IEEE 802.11. However, let us consider sensor networks. The devices employed are power-limited in nature; introducing the conventional clustering approach to the sensor networks provides a unique challenge due to the fact that cluster-heads, which are communication centers by default, tend to be heavily utilized and thus drained of their battery power rapidly. We introduce a re-clustering strategy and a power-limit constraint for cluster-based sensor wireless networks in order to address the power-conserving issues in such networks, while maintaining the merits of a clustering approach. Based on a practical energy model, simulation results show that the improved clustering method can achieve a longer lifetime when compared with the conventional clustering method.

IP multicast is an efficient means of sending to a group. Our protocol is built on top of the existing static hosts IP unicast and multicast forwarding services to avoid triangle routing which always occurs in Mobile IP. Relying only on the existing multicast service model and reconstructing the delivery tree every time a multicast member and/or source moves is not always a good solution. By applying the ideas of bi-directional tunneled multicast, our protocol attempts to hide host mobility from all other members of the group. Therefore, the multicast distribution tree will not be updated for the sake of member location change. Furthermore, our protocol has near shortest delivery paths like the remote subscription protocol. Our protocol can also adapt to the fluctuation of both host movement and the number of mobile members (i.e., having mobility and scalability properties).

The emergence of nomadic applications have generated a lot of interest in next generation wireless network infrastructures which provide differentiated service classes. So it is important to study how the quality of service (QoS) should be guaranteed. To accomplish this, we develop an admission control scheme which can guarantee bandwidth for real-time applications in multihop mobile networks. In our scheme, a host need not discover and maintain any information of the network resources status on the routes to another host until a connection request is generated for the communication between the two hosts, unless the former host is offering its services as an intermediate forwarding station to maintain connectivity between two other hosts. This bandwidth guarantee feature is important for a mobile network to interconnect wired networks with QoS support. Our connection admission control scheme can also work in a standalone mobile ad hoc network for real-time applications. This control scheme contains end-to-end bandwidth calculation and bandwidth allocation. Under such a scheme, the source is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real time applications. In the case of an ATM interconnection, the bandwidth information can be used to carry out intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine via simulation the system performance in various QoS traffic flows and mobility environments. The "on-demand" feature enhances the performance in the mobile environment because the source can keep more connectivity with enough bandwidth to a receiver in the path-finding duration.

The emergence of nomadic applications have generated a lot of interest in next-generation wireless network infrastructures which provide differentiated service classes. So it is important to study how the quality of service (QoS), such as packet loss and bandwidth, should be guaranteed. To accomplish this, we develop am admission control scheme which can guarantee bandwidth for real-time applications in multihop mobile networks. In our scheme, a host need not discover and maintain any information of the network resources status on the routes to another host until a connection request is generated for the communication between the two hosts, unless the former host is offering its services as an intermediate forwarding station to maintain connectivity between two other hosts. This bandwidth guarantee feature is important for a mobile network to interconnect wired networks with QoS support. Our connection admission control scheme can also work in a stand-alone mobile ad hoc network for real-time applications. This control scheme contains end-to-end bandwidth calculation and bandwidth allocation. Under such a scheme, the source is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real time applications. In the case of ATM interconnection, the bandwidth information can be used to carry out an intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine via simulation the system performance in various QoS traffic flows and mobility environments.

We propose a reliable mobile multicast protocol, RRBMoM (Reliable Range Based Mobile Multicast), in IP networks using mobile IP. RRBMoM is an extension of RBRMoM. It provides ACK-based reliability and sender-initialed loss recovery, and uses a tree-based hierarchical structure to alleviate the acknowledgment-implosion problem. A multicast home agent (MHA) acts as a representative of a set of mobile receivers which are roaming within its service range. Only the MHAs send acknowledgments to the sender, instead of all receivers sending their acknowledgments to the sender to prevent acknowledgment-implosion. In addition, the scheme of handoff loss recovery leads to improved throughput and end-to-end delay at the cost of additional backup nodes in the multicast tree. This cost can be dynamically controlled by adjusting a system parameter (i.e., service range). Performance results show that RRBMoM is efficient and adaptive to the dynamics of the system.

The emergence of nomadic applications have generated much interest in wireless network infrastructures that support real-time communications. We propose a bandwidth routing protocol for quality-of-service (QoS) support in a multihop mobile network. The QoS routing feature is important for a mobile network to interconnect wired networks with QoS support (e.g., ATM, Internet, etc.). The QoS routing protocol can also work in a stand-alone multihop mobile network for real-time applications. This QoS routing protocol contains end-to-end bandwidth calculation and bandwidth allocation. Under such a routing protocol, the source (or the ATM gateway) is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real-time applications. In addition, it enables more efficient call admission control. In the case of ATM interconnection, the bandwidth information can be used to carry out intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit (VC) service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine the system performance in various QoS traffic flows and mobility environments via simulation. Simulation results suggest distinct performance advantages of our protocol that calculates the bandwidth information. It is particularly useful in call admission control. Furthermore, "standby" routing enhances the performance in the mobile environment. Simulation experiments show this improvement.

The emergence of nomadic applications have generated a lot of interest in wireless network infrastructures which support multimedia services. We propose a bandwidth routing algorithm for multimedia support in a multihop wireless network. This network can be interconnected to wired networks (e.g. ATM or the Internet) or stand alone. Our bandwidth routing includes bandwidth calculation and reservation schemes. Under such a routing algorithm, we can derive a route to satisfy the bandwidth requirement for the QoS constraint. At a source node, the bandwidth information can be used to decide to accept a new call or not immediately. This is specially important to carry out a fast handoff when interconnecting to an ATM backbone infrastructure. It enables an efficient call admission control. The simulation results show that the bandwidth routing algorithm is very useful in extending the ATM virtual circuit service to the wireless network. Different types of QoS traffic can be integrated in such a dynamic radio network with high performance.

Personal communications and mobile computing will require a wireless network infrastructure which is fast deployable, possibly multihop, and capable of multimedia service support. The first infracture of this type was the packet radio network (PRNET), developed in the 70's to address the battlefield and disaster recovery communication requirements. PRNET was totally asynchronous and was based on a completely distributed architecture. It handled datagram traffic reasonably well, but did not offer efficient multimedia support. Recently, under the WAMIS and Glomo ARPA programs several mobile, multimedia, multihop (M/sup 3/) wireless network architectures have been developed, which assume some form of synchronous, time division infrastructure. The synchronous time frame leads to efficient multimedia support implementations. However, it introduces more complexity and is less robust in the face of mobility and channel fading. In this paper; we examine the impact of synchronization on wireless M/sup 3/ network performance. First, we introduce MACA/PR, an asynchronous network based on the collision avoidance MAC scheme employed in the IEEE 802.11 standard. There, we evaluate and compare several wireless packet networks ranging from the total asynchronous PRNET to the synchronized cluster TDMA network. We examine the tradeoffs between time synchronization and performance in various traffic and mobility environments.

This paper describes a self-organizing, multihop, mobile radio network which relies on a code-division access scheme for multimedia support. In the proposed network architecture, nodes are organized into nonoverlapping clusters. The clusters are independently controlled, and are dynamically reconfigured as the nodes move. This network architecture has three main advantages. First, it provides spatial reuse of the bandwidth due to node clustering. Second, bandwidth can be shared or reserved in a controlled fashion in each cluster. Finally, the cluster algorithm is robust in the face of topological changes caused by node motion, node failure, and node insertion/removal. Simulation shows that this architecture provides an efficient, stable infrastructure for the integration of different types of traffic in a dynamic radio network.

The paper presents a distributed architecture which relies on code division access scheme for multimedia transport in a wireless mobile radio network without a fixed infrastructure. The proposed multicluster architecture has the capability of rapid deployment and dynamic reconfiguration. Without the need of base stations, this architecture can operate in areas without a wired back-bone infrastructure. The presented architecture has two main advantages. First, this architecture can provide spatial reuse of the bandwidth due to node clustering. Second, computer simulation reveals that our cluster structure is robust in the face of topological changes due to node motion, node failure, and/or new node addition. In all, this architecture provides a stable infrastructure for the integration of different types of traffic in a dynamic radio network.