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In-network caching is a popular informationcentric networking (ICN) research topic due to the significant role in improving network performance to provide efficient data delivery. It is managed by a caching strategy that decides what, where, and when the content is cached. Accordingly, numerous caching strategies have been proposed to solve the drawbacks which existed in the default caching strategy to enhance ICN performance, although the majority of the proposed strategies were inadequate to produce efficient performance improvement. Meanwhile, popularity-based caching strategies are the most optimal approach, despite the disadvantages in calculating content popularity. Thus, this study presents an alternative caching strategy, namely Efficacious Content Caching and Eviction Priorities (CCEP), for ICN high performance. The CCEP could precisely calculate the content caching and eviction priorities based on the content popularity through significant factors. Simultaneously, the CCEP avoids the existing disadvantages in present caching strategies to obtain the highest performance in hop reduction, cache hit ratio, and the number of caching operations. The CCEP demonstrated significantly higher performance than the default caching strategy by elevating the hop reduction to 1667% and cache hit ratio by 1815%, while reducing the number of caching operations by 99%. The CCEP could also increase hop reduction by 53% and cache hit ratio by 17%, while reducing the number of caching operations to 21% compared to other improved caching strategies. [ABSTRACT FROM AUTHOR]

The global human population is increasing, and this increase is more common among the elderly (people aged ≥60 years old and above). The elderly population is approaching 13% of the global population. Consequently, geriatric-related illnesses are expected to be more prevalent, exerting explicit pressure on healthcare systems. We explored the healthcare utilisation patterns among the elderly at public referral hospitals in Malaysia. We performed a retrospective cross-sectional study with a representative sample of elderly patients' medical records from four referral public hospitals in Malaysia. Multiple types of data were collected from the hard-copy medical records via a structured observational checklist. A total of 434 medical records were included in the study via systematic random sampling. There were a total of 561 inpatient episodes of care. Up to 54.7% of the episodes were in the medical wards. The average length of stay was 5.8 days per episode. An average of 27.48 laboratory investigations were consumed per inpatient episode. Approximately 8.91 medications and 0.89 antibiotics were consumed per episode. Elderly patients consume a large proportion of the hospital services in Malaysia. It is recommended that the authorities should adopt health promotion and disease prevention policies that can reduce the high healthcare utilisation among elderly Malaysians. [ABSTRACT FROM AUTHOR]

Future telecommunication systems and networks are expected to provide a variety of integrated broadband services to the customers. There has been a tremendous interest in applying Code Division Multiple Access (CDMA) techniques to fiber optic communication systems. This technique is one of the multiple access schemes that is becoming popular because of the flexibility in the allocation of channels, ability to operate asynchronously, enhanced privacy and increased capacity in bursty networks. This project is focusing on designing 2D OCDMA system with the hardware implementation of design using FPGA. The coding techniques in OCDMA are time versus wavelength and amplitude versus phase. 2D OCDMA coding incorporates both wavelength selection and time distribution. The data bit would be encoded as consecutive chips with various wavelengths. The code architecture seeks to produce codes with high autocorrelation and low cross-correlation properties. Code length is an essential aspect of code and device architecture for coding characteristics. The hardware implementation of the system is designed by using FPGA De1-SoC. The FPGA have the abilities to enhance the transmission of data to the receiver in a short period of time. The performance of 2D OCDMA system is expected to surpass 1D OCDMA system in terms of BER and the number of simultaneous users that can be supported. The system encoder and decoder were designed using optical switch, splitter, combiner and modulator. The performance of 2D OCDMA system in terms of time spreading and wavelength spreading is also compared which shown a huge difference in the results. The best performance of the system is when the number of wavelength (M) is fixed to 18 and the number of times spreading (N) is 31 which can support 350 more simultaneous users.dc [ABSTRACT FROM AUTHOR]

In this paper, an optical code division multiple access (OCDMA) system was analysed to improve the bit error rate (BER) performance at 10 Gbps. The improvements to this system were based on a modified double weight code and a NAND subtraction technique and aimed to support the large number of active users in the fibre-to-the-home network. The system performance was investigated through extensive theoretical and numerical simulation analyses. The theoretical and simulation results revealed that the new detection technique exhibits improved BER performance compared to conventional techniques, such as complimentary subtraction techniques. The system performance was characterised by the signal-to-noise ratio, the bit error rate (BER), and various transmit powers ( $$P_{sr} - 10$$ dBm). The results show that the proposed system, which is based on a new detection technique, can achieve the optimal BER with a high number of users and maintains the error floor transmission rate $$(\le 10^{-9})$$ . [ABSTRACT FROM AUTHOR]

In this paper, we present the impact of the multi-diagonal (MD) code for high data rate in spectral amplitude coding optical code division multiple-access (SAC-OCDMA) networks. An MD code structure for SAC-OCDMA system is presented. The MD code can be flexibly generated for any weight and number of users by using a combination of diagonal matrices. Several advantages of the MD code family are: the cross-correlation value remains zero even in case of an increased number of users for any weight value, supporting large number of users, and easy code construction. Thus, these features show the MD code family be a solution to enhance the data rate of SAC-OCDMA networks. Based on the theoretical and simulation evaluation, MD code is shown to provide a much better performance compared to existing SAC-OCDMA codes. The ability of MD code to support simultaneous transmissions at different high data rate has been successfully established through the simulated results of the 0.24 Tbps (12 Gbps × 20 users) and 0.3 Tbps (15 Gbps × 20 users) data-rate transmission networks. [ABSTRACT FROM AUTHOR]

This article presents a new code—the dynamic cyclic shift code—for spectral amplitude coding–optical code division multiple access systems. One of the important properties of the dynamic cyclic shift code is that the number of users can be increased without increasing the weight value. System performance was evaluated by using both theoretical analysis as well as the simulation experiment. The analysis results show that the proposed dynamic cyclic shift code can support more users in spectral amplitude coding–optical code division multiple access systems compared to spectral amplitude coding–optical code division multiple access codes. It was ascertained by performance evaluation that the dynamic cyclic shift code possesses ideal properties for use in spectral amplitude coding–optical code division multiple access systems. [ABSTRACT FROM AUTHOR]

In this study, the spectral efficiency (SE) of bipolar spectral-amplitude coding optical code-division multiple-access (SAC-OCDMA) systems operating with incoherent sources is analysed. The analytical expressions of the model were derived to assess the performance of SAC-OCDMA systems, taking into account the intensity noise as the primary source of noise. Four different SAC codes were used to evaluate and compare the SE against the number of active users and code length for a bit-error rate (BER) of 10-11. The investigated codes are Hadamard, modified quadratic congruence (MQC), balanced incomplete block design (BIBD) and zero cross-correlation (ZCC). Our analytical results revealed that ZCC code has the ability to support more users at a high data rate up to 2.5 Gbps and offers significant SE enhancement in bipolar SACOCDMA system over other SAC codes under investigation. In addition, bipolar encoding improves the SE compared with unipolar technique, for example bipolar ZCC has 7.7-dB SE advantage than unipolar ZCC. Furthermore, when BER requirement of the system decreases, the SE can be increased. [ABSTRACT FROM AUTHOR]

In this paper we have modelled and simulated a 1.6 Tb/s (100⨰16 Gb/s) optical system based on spectral amplitude coding for the optical code-division multiple-access (SAC-OCDMA) scheme. In order to reduce the effect of multiple-access interference, we have employed a new family of SAC-OCDMA codes called as a multi-diagonal (MD) code. The new code family based on the MD code reveals properties of zero cross-correlation code, flexibility in selecting the code parameters and support of a large number of users, combined with high data rate. Both the numerical and simulation results have demonstrated that our optical system based on the MD code can accommodate maximum numbers of simultaneous users with higher data rate transmission and lower bit error rates, when compared to the former SAC-OCDMA codes. [ABSTRACT FROM AUTHOR]

A hybrid subcarrier multiplexing (SCM) technique incorporating spectral amplitude coding and optical code division multiple access (SAC-OCDMA) technologies is investigated using both numerical and simulation methods. The hybrid SCM/SAC-OCDMA system combines the two above schemes in such a way that it is robust to multiple access interference and reveals much enhanced channel data rate. We improve the overall performance of the hybrid SCM/SAC-OCDMA system based on spectral amplitude coding to suppress a number of impairments and improve its sensitivity at a bit error rate of 10-9. As a result, the system suggested by us, which is based on a dynamic cyclic shift code, shows better performance when compared with the standard SAC-OCDMA systems employing the conventional code. [ABSTRACT FROM AUTHOR]

This paper demonstrates an 8-channel spectral-sliced WDM system using 0.2-nm channel spacing. We have investigated the system performance of NRZ modulation format for this system with different bit rates such as 622 Mb/s, 1 Gb/s and 1.5 Gb/s, respectively. We characterize the system performance as the bit-error-rate (BER) received against the system bit rates. Simulation results show that the NRZ modulation format performs well for 622 Mb/s system bit rates compared to 1 Gb/s and 1.5 Gb/s system bit rates. Using this narrow channel spectrum-sliced technique, the total number of multiplexed channels can be increased greatly in WDM system. Therefore, 0.2-nm channel spacing spectrum-sliced WDM system is highly recommended for the optical access networks, like the fiber-to-the-building (FTTB) or the fiber-to-the-home (FTTH). [ABSTRACT FROM AUTHOR]

In this paper, we will focus on the modulation format used to create the optical pulses, which are return-to-zero (RZ), and non-return-to-zero (NRZ). Bit error rate (BER) performance is evaluated based on double weight (DW) code. Optical code division multiple access (OCDMA) system is considered a promising technique for fiber-to-the-home (FTTH) access networks. The performance of RZ against NRZ is compared through simulation by using the Optisystem software version 7. We used two networks designed as follows: one used a RZ pulse generator and the second used a NRZ pulse generator, and both systems were tested with and without erbium doped fiber amplifier (EDFA). It has been found that the NRZ pulse generator in this system is better than the RZ pulse generator for all simulation results. The conversion used a Mach-Zehnder interferometer (MZI) wavelength converter. Also, we are proposing a detection scheme known as the AND subtraction detection technique implemented with fiber Bragg grating (FBG) which acts as an encoder and decoder. This FBG is used to encode and decode the spectral amplitude coding DW code in the OCDMA system. The performances are characterized through BER and bit rate (BR), and also the received power at various bit rates. [ABSTRACT FROM AUTHOR]

A new code of optical code division multiple access (OCDMA) based on spectral amplitude coding (SAC) is described and analysed. The coding technique is called random diagonal (RD) code. One of the important properties of this code is that the cross-correlation at data segment is always zero, which means that phase intensity induced noise (PIIN) is reduced. From the construction of RD code sequence, the authors can see that the RD code is constructed using code segment and data segment. Using this code property, RD code is implemented using coherent source (multi-laser) and incoherent source (light emitting diode) for the code segment and data segment, respectively. RD code using two multi-sources (incoherent and coherent) can be considered as an effective way for maximising the capacity while minimising the cost of SAC–OCDMA. It is shown that the system using this new code matrices not only suppresses PIIN, but also allows a larger number of active users compared with other codes. [ABSTRACT FROM AUTHOR]

In this research, the radial Schrödinger equation is solved analytically using the Nikiforov-Uvarov method with the Cornell potential. The energy spectrum and the corresponding wave function are obtained in close form. The effect of Topological Defect on the thermal properties and mass spectra of heavy mesons such as charmonium and bottomonium are studied with the obtained energy spectrum. It is found that the presence of the Topological Defect increases the mass spectra and moves the values close to the experimental data. Our results agreed with the experimental data and are seen to be improved when compared with other works. [ABSTRACT FROM AUTHOR]

An abstract of the article "The UNU-CBGs: development and deployment of a real international open source Casemix grouper for resource challenged countries," by S.M. Aljunid and colleagues is presented.

An abstract of the article "The Impact of Introducing Case Mix on the Efficiency of Teaching Hospitals in Malaysia," is presented by S. M. Aljunid and colleagues in the 26th Patient Classification Systems International (PCSI) Working Conference held in Munich, Germany from September 15-18, 2010.

An abstract of the article "Can Clinical Pathways enhance the implementation of a Casemix system? A case study in a teaching hospital in Malaysia," by S. M. Aljunid and colleagues is presented.

In this study, the effects of Aharonov-Bohm (AB) and magnetic fields on the thermodynamic and magneto-transport properties of TiH diatomic molecule using the Deng-Fan potential as a model are investigated. The functional analysis approach (FAA) is used to solve the Schrodinger equation in the presence of magnetic and AB fields with Deng-Fan potential. The energy equation, as well as the wave function, have been derived. The analytic expressions for the thermo-magnetic and transport properties of the Deng-Fan potential are derived using the energy equation and the partition function. These properties obtained are thoroughly analysed utilising graphical representations. Our analysis shows that the magnetic susceptibility of the TiH exhibits a diamagnetic behaviour, and the specific heat capacity behaviour agrees with the famous Dulong-Petit law when the system is subjected to AB field variations and a fixed magnetic field. Albeit, a slight anomaly is observed in the behaviour of the specific heat capacity. Our findings will be valuable in various fields of physics, including chemical and molecular physics and condensed matter physics, where the derived models could be applied to study other diatomic molecules and quantum dots, respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT Outdoor localization estimation method for mobile based on single base station scattering distance in an urban area environment is proposed in this paper. This new approach is deployed for both Line-of-site and NonLine-of-site by using a single base station technique based on the measured scattering distances which are computed from the numerous multipath components signals. Those signals are coming from the scatterers around the mobile station (MS) and the base station (BS) by utilizing the time of arrival and the Angle of arrival effects. Site of the student's hostel at Universiti Malaysia Perlis was chosen to be our proposed scenario. A proper technique depending on the prior knowledge about the geometrical coordinates of some fixed obstacles surrounds both the subscriber and only one BS is suggested to identify the MS location. As a result, the localization of 70% from the subscribers can be identified which is more satisfactory compared to 67% U.S. Federal Communications Commission standard within 125 m. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1546-1551, 2016 [ABSTRACT FROM AUTHOR]

This paper is motivated by searching for the perfect pattern for the spectroscopy spectra using artificial neural networks (ANN) using python programming coding. The pattern from the spectroscopy is based on the absorption and emission of light and other radiation by materials in relation to the wavelength dependence of these processes. Spectral equipment such as spectrometers, spectral analysers, spectrographs, or spectrophotometers is utilised to determine spectrum values. The problem in this spectroscopy is to identify the sample or analyte, which can be solved by a prediction model for spectroscopy using Python. These problems occur when finding the best algorithm of pre-processing techniques that can predict any model accurately into an understandable format for prediction models. Various types of pre-processing techniques have been used, such as Multiplicative Scatter Correction (MSC), Inverse MSC, Extended MSC (EMSC), Extended Inverse MSC, de-trending, Standard Normal Variate (SNV) and normalisation in order to get a better r2 value. In this project, we find the r2 and the root mean square error (RMSE) to evaluate the prediction values and the actual values. First, choosing pre-processing techniques and then finding the best statistical method for constructing predictive models that produce high accuracy. We used ANN in this project as a prediction model. Based on the results, we managed to achieve our objective, which is that the prediction model has more than 90% of accuracy. Furthermore, the results show that our prediction model has 1.0 accuracy at 100 Epoch with a 0.3 learning rate. Finally, we can conclude that our prediction model can be used to predict the spectroscopybased data format. [ABSTRACT FROM AUTHOR]

Over the last few years, free space optical communication (FSO) has emerged as a viable alternative to radio frequency communication. It provides a promising high-speed pointto-point communication solution. However, atmospheric absorption, scattering and turbulence degrade wireless optical communication significantly, lowering device efficiency. The attenuation of signals due to the above atmospheric reasons is another major factor that affects device efficiency. The atmospheric turbulence conditions are observed implemented into different models of FSO systems, such as Single Input Single Output (SISO), Multiple Input Multiple Output (MIMO), Wavelength Division Multiplexing MIMO (WDM-MIMO) and proposed model Double Multiple Input Multiple Output (DMIMO) using the Gamma-Gamma model for a variety of reasons. The OptiSystem 7.0 software was used to run simulations to study how various weather conditions (clear, haze and fog) affected the performance of the channel. Simulation results show that implementing Double Multiple Input Multiple Output (DMIMO) techniques for FSO systems provides high quality factor for various ranges while still achieving accurate transmitted data at the receiver side. In the presence of atmospheric turbulence conditions such as clear air, haze and fog, performance improvements signal power levels, quality factor and link distance range have been demonstrated. [ABSTRACT FROM AUTHOR]

In recent years, Free Space Optics (FSO) communication provides attractive bandwidth enhancement with unlicensed bands worldwide spectrum. However, the link capacity and availability are the major concern in the different atmospheric conditions. The reliability of the link is highly dependent on weather conditions that attenuate the signal strength. In the tropical region specifically in Borneo Sarawak, rain is the dominant weather that act as the limiting factor to FSO performance. Hence, this study highlights on the impact of rain attenuation to the performance of FSO communication system. The finding is based on atmospheric model and performed through the simulation of OptiSystem software. The design of parameters in the simulation involves iteration of wavelengths, size of transmitter and receiver aperture and beam divergence angle. The simulation result shows longer wavelength 1550nm is much better than 785nm. The 0.25m of receiver aperture and transmitter aperture at 0.05m can reduce the loss. Narrow beam divergence angle can reduce the power consumption and maintain the high power at receiver. The analysis indicates that proposed FSO communication system is capable to withstand the attenuation from rain weather. [ABSTRACT FROM AUTHOR]

A near zero dispersion flattened porous core photonic crystal fibre having ultra‐flat low material loss suitable for terahertz (THz) transmission is represented. A novel type of geometrical structure of air hole position has been proposed in this design. Numerical analysis exhibits effective material loss (EML) of 0.03746 cm−1 at 1.0 THz operating frequency and a flat EML of 0.0398 cm−1 from 1.5 to 5.0 THz with absolute EML coefficient of ±0.000416 cm−1. The proposed waveguide shows near zero flat dispersion of 0.4 ± 0.042 ps/THz/cm in the frequency range from 1.25 to 5.0 THz. [ABSTRACT FROM AUTHOR]

Cardiovascular mortality is within the top five causes of death from noncommunicable disease based on World Health Organization profile. Around 20% of heart failure patients are readmitted within 30 days worldwide. Readmission within 30 days for congestive heart failure often related to non-compliant to fluid restriction, natural progression of the disease or pre-mature discharge. The study aims to evaluate the 30 days readmission rate of congestive heart failure in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from the year 2016-2017 using casemix data and to determine the associated factors related to it. Based on the data coding, cost of readmission incurred was calculated. The 30-days readmission rate of heart failure to UKMMC in the year 2016-2017 was 53.5% & 43.5%, higher than the developed countries standard but similar to that of local teaching hospitals. After adjustment, age and level of severity are the only significant associated factors for the 30-days readmission rate. Shorter average length of stay (ALOS) & lower extra-tariff were achieved for readmission of heart failure. Total of RM80,329.73 was saved in the year 2017 from prompt treatment and comprehensive care plan of treating 19.3% level 3 severity patients at level 1 ALOS and tariff-cost. The 30-days readmission rate for heart failure in UKMMC was comparable to local teaching hospitals. The reduction of 30-days readmission rate in 2017 saved much cost, shows good clinical governance and advanced treatment strategy. Casemix can be used to guide budget allocation for the cardiology department of UKMMC. [ABSTRACT FROM AUTHOR]

A near zero dispersion flattened porous core photonic crystal fibre having ultra-flat low material loss suitable for terahertz (THz) transmission is represented. A novel type of geometrical structure of air hole position has been proposed in this design. Numerical analysis exhibits effective material loss (EML) of 0.03746 cm-1 at 1.0 THz operating frequency and a flat EML of 0.0398 cm-1 from 1.5 to 5.0 THz with absolute EML coefficient of ±0.000416 cm-1. The proposed waveguide shows near zero flat dispersion of 0.4 ± 0.042 ps/THz/cm in the frequency range from 1.25 to 5.0 THz. [ABSTRACT FROM AUTHOR]

We investigate numerically a defected-core hybrid photonic crystal fibre (H-PCF) with a circular core and a rectangular-shaped cladding, which is designed for compensation of residual dispersion over a wide wavelength range. Our simulation results testify that this H-PCF exhibits a large negative dispersion (- 868 ps/(nm km)) over the E+S+C+L telecommunication bands, with the relative dispersion slope perfectly matching that of a single-mode fibre at the operating wavelength 1550 nm. The H-PCF reveals the birefringence 1.06×10-2 at the operating wavelength. In order to evaluate the sensitivity of optical properties of our H-PCF, we study the effect of variations of its parameters as large as ±2% from their optimal values. Due to its specific characteristics, the H-PCF suggested in this work can be considered as an excellent candidate for compensating dispersion, maintaining a single polarization in the optical fibre transmission systems, and numerous optical sensing applications. [ABSTRACT FROM AUTHOR]