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Skin drug administration is the method used to provide drugs for local or systemic therapy, which is recognized for clinical usage. It is the third-largest method of medication delivery, after only intravenous administration and oral administration. Using a transdermal delivery method makes the administration easy, and blood concentration and adverse effects can be reduced. A microneedle is a micron-sized needle with a short height of no more than 500 micrometers and a width of no more than 50 micrometers. The needle comes into contact with the epidermal layer of the skin before it gets to the dermal layer, where there is no discomfort. Several materials, such as metals, inorganic, and polymer materials, are used to create microneedles. All different types of microneedles are employed in different scientific disciplines. In recent years, microneedles have been utilized as a drug delivery method to carry pharmaceuticals, genetic codes, proteins, and vaccinations. In chemotherapy, diagnostics, treatment, and immunotherapy, microneedles were utilized.

The growing demand for bandwidth and spectrum has inspired the ongoing efforts to establish the future 5G network supporting vertical sectors such as cyber-physical systems (CPS). Cooperative communication is one of the requisite techniques to improve coverage, network capacity and reduce power consumption in the network. In this paper, a symbiotic two-phase intelligent transmission is considered. The first phase occurs between the source and the candidate relays, and involves the selection of a set of “reliable relays”. The second phase occurs between the reliable relays and the destination, and involves the selection of the “best relay” for transmission. Dynamic relay selection using k-means clustering is used to detect the most significant correlation between all the channel state information (CSI) attributes in the system. The work identified the reliable relays while reducing the number of relay nodes for the second transmission phase. Contextual scenarios are created with typical network configuration using three geographical locations Coventry, Birmingham and London. An experimental validation is done with Omnet++ environment for the scenarios of three geographical locations. A natural grouping of mobile users is carried out leveraging the relay capabilities. The results are validated using support vector machine (SVM) classification algorithm. Considering urban environment deployment of relay nodes, metrics such as signal-to-noise-plus-interference ratio (SINR), attenuation, signal to noise ratio (SNR), link quality, k-means clustering, accuracy, and root mean square error (RMSE) are investigated for the Direct-2-Direct (D2D) capable relays. It was observed that the proposed technique both outperforms the other fixed-parameter relay selection techniques and improves with larger datasets unlike the other techniques.

This paper investigates the impact of sunlight radiation at different times of the year on the performance of vehicular visible light communication (VVLC) for an emergency service vehicle (ESV). The paper considers the worst-case scenario of the sunlight being directly incident onto the receiver. The sunlight incidence model takes into account the apparent solar time as well as the direct, reflected and diffuse sunlight radiation. The performance of the VVLC is evaluated for pulse amplitude modulation (PAM) scheme. The signal to noise ratio (SNR) and bit error rate (BER) is simulated using a transmitter located at the top of ESV and receiver on the tail light height of a vehicle in front of the ESV. The simulation observed that the worst link distance decreases by up to 5 m when the sun minimum irradiation varies to the maximum during the year. The worst link distance is obtained when using binary PAM scheme while better performance could be obtained using higher-order PAM schemes.

Heat generation and plastic deformation during Friction Stir Welding (FSW) produce profound changes in the microstructure and structural properties of welded joints. Strengthening precipitate, grain size and crystallographic texture evolution are the most important microstructural changes in the case of welding aluminium alloys. An interaction relationship has been developed in this study to understand the evolution of microstructure during FSW of Al-Mg-Si alloy for a wide range of welding temperatures and plastic deformations by controlling two important process parameters (tool rotation and welding speeds). Electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) have been used for microstructural characterisation. The mechanical properties were evaluated using microhardness, tensile and low cycle fatigue tests. In all cases, fine recrystallised equiaxed grains with a partial fibre texture was evolved in the nugget zone. Microstructural development was found to be significantly influenced by the weld pitch (welding speed/rotation speed), as it is controlled the heat input, cooling rate, exposure time and plastic deformations. The strength of the FSW joints is improved by increasing the welding speed because of grain refinement, incomplete dissolution or re-precipitate of strengthening precipitates M g 5 S i 6 ( β ) ´ ´ and the introduction of edge dislocations. The fatigue performance of FSW joints is dependent on grain size with a remarkable improvement in the fatigue life observed for smaller grain sizes.

This paper investigates the potential of an early warning system to warn drivers of emergency service vehicles (ESV) prior to their arrival as a suitable replacement for sirens mounted on these vehicles. In this paper, a proof-of-concept system, with the intention of developing a full-scale system for widespread implementation is developed resulting in a reduction of noise pollution caused by sirens. The system was tested by modelling in small-scale using remote controlled (RC) cars and smart traffic lights to evaluate the system and its viability for the future. This paper achieves a working prototype and concludes that the system is viable. Although global positioning system (GPS) is inaccurate for a small-scale system, accuracy is within the GPS specifications and should not impact a full-scale implementation.

This paper demonstrates a multi-hop underwater visible light communication (VLC) system using light emitting diodes (LEDs). It is demonstrated that using a multi-hop technique, the overall underwater VLC distance can be increased significantly without adding significant complexity to the physical layer. The performance of the multi-hop system is compared to a single-hop technique utilizing three types of water in the laboratory environment, namely sea, canal, and tap water. The obtained results validate that a multi-hop technique can be a viable solution to overcome the problem of limited underwater communication range.

Generative models, which can generate bursty error sequences with similar burst error statistics to those of descriptive models, have an immense impact on the wireless communications industry as they can significantly reduce the computational time of simulating wireless communication links. Adaptive generative models aim to produce any error sequences with any given signal- to-noise ratios (SNRs) by using only two reference error sequences obtained from a reference transmission system with two different SNRs. Compared with traditional generative models, this adaptive technique can further considerably reduce the computational load of generating new error sequences as there is no need to simulate the whole reference transmission system again. In this paper, reference error sequences are provided by computer simulations of a long term evolution (LTE) system. Adaptive generative models are developed from three widely used generative models, namely, the simplified Fritchman model (SFM), the Baum-Welch based hidden Markov model (BWHMM), and the deterministic process based generative model (DPBGM). It is demonstrated that the adaptive DPBGM can provide accurate burst error statistics and bit error rate (BER) performance of the LTE system, while the adaptive SFM and adaptive BWHMM fail to do so.

Errors encountered in digital wireless channels are not independent but rather form bursts or clusters. Error models aim to investigate the statistical properties of bursty error sequences at either packet level or bit level. Packet-level error models are crucial to the design and performance evaluation of high-layer wireless communication protocols. This paper proposes a general design procedure for a packet-level generative model based on a sampled deterministic process with a threshold detector and two parallel mappers. In order to assess the proposed method, target packet error sequences are derived by computer simulations of a coded enhanced general packet radio service system. The target error sequences are compared with the generated error sequences from the deterministic process-based generative model using some widely used burst error statistics, such as error-free run distribution, error-free burst distribution, error burst distribution, error cluster distribution, gap distribution, block error probability distribution, block burst probability distribution, packet error correlation function, normalized covariance function, gap correlation function, and multigap distribution. The deterministic process-based generative model is observed to outperform the widely used Markov models. Copyright © 2013 John Wiley & Sons, Ltd.

This paper presents the design, development and test of an underwater visible light communication system for the deep sea divers. To achieve a practical communication range, frequency modulation technique has been utilized to modulate the voice signal which is eventually transmitted using visible light. Blue and green light emitting diodes have been chosen to design a full duplex system for simultaneous communication. The proposed system achieved a bidirectional communication range of approximately 3.5 m using off-the-shelf components and without using any optical concentrator.

Objective: The objective of this study is to develop a controlled release matrix tablet of candesartan cilexetil to reduce the frequency of administration,enhance bioavailability and improve patient compliance; a once daily sustained release formulation of candesartan cilexetil is desirable.Methods: The prepared tablets from F1 to F24 were evaluated with different evaluation parameters like weight variation, drug content, friability,hardness, thickness and swelling ability. In vitro release for all formulas were studied depends on the type and amount of each polymer, i.e. (16 mg,32 mg and 48 mg) respectively beside to the combination effect of polymers on the release of the drug from the tablet.Results: In vitro release showed that formula 13 had the faster release (100% after 4 h) which contained acacia (1:1) and the lowest sustain releasewas showed for F7 (73% after 8 h) which contained HPMC K100M (1:1). Formula 1 was an 89 % release after 8 h which contain eudragit RS100; F4was a 100 % release after 5 h which contain Na CMC, F10 was a 100% after 8 h which contain xanthan gum and F16 was a 100 % release after 5 hwhich contain tragacanth polymer. Formula 9 had a lower release than F7 and F8 respectively. Formula 7 can be used for sustain oral drug delivery ofcandesartan cilexetil while Formula 13 can be used in contrary as fast release tablets for faster response.Conclusion: Controlled drug delivery system is promising for less dosing and higher patient compliance.Keywords: Angiotensin II receptor antagonist, Hypertension, Matrix system, Control release.

Hybrid Automatic Retransmission reQuest (HARQ) is an effective technique to improve the reliability of wireless communication systems by detecting, correcting, and retransmitting the erroneous packets. Packet-level error sequences obtained from physical layer wireless communication systems are important for the design and performance evaluation of high layer protocols, e.g., HARQ. In this paper, we utilize the open source Vienna long-term evolution (LTE) simulator to study the impact of HARQ on the burst error statistics of packet-level error sequences. Moreover, we propose a generative model that can generate packet-level error sequences with predicted burst error statistics similar to those of error sequences obtained from wireless systems with HARQ. Simulation results demonstrate that the proposed generative model is accurate and efficient in predicting the behavior of HARQ in terms of a set of burst error statistics rather than predicting the packet error rate (PER) only.

Generative models are created to be used in the design and performance assessment of high layer wireless communication protocols and some error control strategies. Generative models can replace real digital wireless channels to significantly reduce the time and complexity of system simulation. The errors occurring in digital wireless channels are not independent but form clusters or bursts. Generative models have to produce error sequences having similar burst error statistics to those of original error sequences obtained from real digital systems. In this paper, we propose a generative hidden Markov model (HMM) with three layers. It is shown that the proposed three layered HMM can generate error sequences that have statistics compatible with those of original error sequences derived from an enhanced general packet radio service (EGPRS) transmission system.

Generative models hold the promise of reducing the computational load and cost caused by directly simulating a real system. They are vital to the design and performance evaluation of error control schemes and high layer wireless communication protocols. Therefore, designing an efficient and accurate generative model is highly desirable. Moreover, the errors encountered in digital wireless channels exhibit correlation among them. This stimulates us to construct a Markovian based generative model with two embedded processes. The first process is dedicated to assembling error bursts with error-free bursts, whereas the second one is devoted to creating individual error bursts employing the maximum gap norm within error bursts. This premise is utilized in this paper to show that the resulting generative model can generate error sequences with desired bit correlations and is capable of statistically matching a descriptive model, derived from an enhanced general packet radio service (EGPRS) transmission system, regardless of the configuration of its error sequences.