PS Ratio Research Articles

Nitrospira dominant pin-point flocs with granule-like settleability in stirred tank reactors with oxic/hypoxic/oxic zones.

The characteristics of biomass and microbial community dynamics, in relation to autotrophic nitrification, were studied in two 20 L stirred tank reactors (STR) with oxic/hypoxic/oxic zones. The bioreactors were fed with synthetic wastewater with stepwise increasing ammonia concentrations (50-200 N mg/L) without organic substrate in the first phase (autotrophic phase) for 35 days (R1) and 15 days (R2), followed by a heterotrophic phase (with supplementation of organic substrate). The settling properties of the biomass, represented by pin-point flocs, gradually improved in both reactors during the autotrophic phase. The pin-point flocs of R1 exhibited granule-like settling properties. The SVI30 in RI gradually improved to 29 mL/g MLSS, and the corresponding SVI30/ SVI10 gradually improved to 0.88 during the autotrophic phase. The settling properties of the biomass deteriorated in both bioreactors during the heterotrophic phase. The protein to polysaccharide ratio (PN:PS ratio) gradually increased in the extracted EPS (in both, loosely bound (LB) and tightly bound (TB) EPS) during the autotrophic phase, in both bioreactors. The TB:LB EPS ratio was higher when the pin-point flocs of R1 showed granule-like settling properties, followed by a decline in TB:LB EPS ratio during the heterotrophic phase. A combination of molecular approaches (droplet digital-PCR (dd-PCR) and 16S rRNA gene sequencing) revealed that Nitrospira were the predominant nitrifying bacteria in the pin-point flocs that show granular sludge-like settling properties during autotrophic phase in R1. Comammox Nitrospira was the dominant ammonia oxidizer in seed biomass and at low ammonia concentrations in both bioreactors. The relative abundance of canonical ammonia-oxidizing bacteria increased with an increase in influent-ammonia concentrations.

Red mud waste/nanoclay/polystyrene‐modified epoxy hybrid composites: Mechanical, thermal, and flammability properties

AbstractIn this study, bisphenol A‐type epoxy (ER) and epoxy phenol novolac resins (EPN) with two amine‐type curing agents (KH 816 and IPOX EH 2041) having different total amine values were selected. The mechanical properties and density of the EPN resin were found higher in the case of both curing agents. EPN was modified with polystyrene (EPN‐PS) and used as a matrix using an IPOX hardener. Nano‐ and hybrid composites were prepared with pristine and modified with tetramethylammonium chloride nano montmorillonite (NC and MNC), and red mud waste (RMW). The chemical structure was elucidated by the Fourier transform infrared (FT‐IR). The composites were characterized by scanning electron microscopy and x‐ray diffraction. Appropriate PS and NC ratio was accepted as 4% and 2% by weight, respectively. Curing degrees calculated from the FT‐IR spectra of ER, EPN, and EPN‐PS were 99.3%, 99.9%, and 86.5%, respectively. A comparative study of the two binary systems; (i) 2 wt% NC‐(15–35) wt% RMW; and (ii) 2 wt% of MNC‐(15–35) wt% of RMW on the mechanical, thermal, and flammability properties of EPN‐PS matrix was carried out. The appropriate RMW ratio was 30 wt%. Hybrid composites with 25–30 wt% RMW can be considered self‐extinguishing materials.

Extremely High-Quality Periodic Structures on ITO Film Efficiently Fabricated by Femtosecond Pulse Train Output from a Frequency-Doubled Fabry-Perot Cavity.

This study developed a novel frequency-doubled Fabry-Perot cavity method based on a femtosecond laser of 1030 nm, 190 fs, 1 mJ, and 1 kHz. The time interval (60-1000 ps) and attenuation ratio (0.5-0.9) between adjacent sub-pulses of the 515 nm pulse train were able to be easily adjusted, while the efficiency was up to 50% and remained unchanged. Extremely high-quality low-spatial-frequency LIPSS (LSFL) was efficiently fabricated on an indium tin oxide (ITO) film using a pulse train with a time interval of 150 ps and attenuation ratio of 0.9 focused with a cylindrical lens. Compared with the LSFL induced by the primary Gaussian pulse, the uniformity of the LSFL period was enhanced from 481 ± 41 nm to 435 ± 8 nm, the divergence of structural orientation angle was reduced from 15.6° to 3.7°, and the depth was enhanced from 74.21 ± 14.35 nm to 150.6 ± 8.63 nm. The average line edge roughness and line height roughness were only 7.34 nm and 2.06 nm, respectively. The depths and roughness values were close to or exceeded those of resist lines made by the interference lithography. Compared with the common Fabry-Perot cavity, the laser energy efficiency of the pulse trains and manufacturing efficiency were enhanced by factors of 19 and 25. A very colorful "lotus" pattern with a size of 30×28 mm2 was demonstrated, which was covered with high-quality LSFLs fabricated by a pulse train with optimized laser parameters. Pulse trains can efficiently enhance and prolong the excitation of surface plasmon polaritons, inhibit deposition particles, depress ablation residual heat and thermal shock waves, and eliminate high-spatial-frequency LIPSS formed on LSFL, therefore, producing extremely high-quality LSFL on ITO films.

Investigation of the catalytic performance of coal gangue char on biomass pyrolysis in a thermogravimetric analyzer and a fixed bed reactor

• Coal gangue rich in metals was used to prepare char-supported catalysts. • Coal gangue char can reduce the activation energy required for pine pyrolysis. • The yield of gas increased with the increase of the coal gangue char mass ratio. • The liquid product yields decreased by 19.01% at PS and CG mass ratio of 1:2. Developing low-cost and high-performance catalysts is an important part of the development of biomass pyrolysis technologies. In this study, the coal gangue rich in metals was used to directly prepare a char-supported catalyst, and metals in coal gangue were hoped to act as catalytic sites for in-situ biomass catalytic pyrolysis and secondary tar cracking. The influence of coal gangue char on pine pyrolysis behavior and kinetics was investigated in the thermogravimetric analyzer and a fixed bed reactor. The thermogravimetric analysis showed that the addition of coal gangue char caused the movement of the initial weight loss temperature and the maximum weight loss peak of the samples to the high-temperature region. With the increase of the coal gangue char mass ratio, lower apparent activation energies of the samples were achieved in the conversion range of 0.2–0.8. Through fixed-bed isothermal pyrolysis experiments, it was found that the yield of gas increased with the increase of the coal gangue char mass ratio, while the tar yield decreased quickly. The yield of H 2 and CO was significantly improved by the coal gangue char, further confirming the catalytic performance of coal gangue char on the cracking of tar molecules.

Secure energy efficiency: Power allocation and outage analysis for SWIPT-in-DAS based IoT

In this paper, we study secure energy efficiency (SEE) for simultaneous wireless information and power transfer (SWIPT) in a distributed antenna system (DAS) based IoT network. We consider a system in which both the legitimate user (Bob) and the eavesdropper (Eve) rely on the energy harvested from the received radio signal. Firstly, with perfect channel state information (CSI), we formulate the maximization of SEE as a constrained optimization problem. In this problem, we aim to highlight the advantage of SWIPT in exploiting the Eve’s energy harvesting requirement. This is achieved by defining a charge constraint in the SEE optimization problem which ensures that the Eve is deprived of its only energy source. Next, considering the fact that perfect CSI is hard to achieve in practice, we characterize the system performance in terms of the outage probability (OP) of SEE. For the given SWIPT-in-DAS setup, we derive the closed form expression for the OP of SEE and with the help of numerical results, we study the effect of transmit power levels, number of distributed antenna (DA) ports and the PS ratio of devices. To the best of our knowledge, this is the first attempt to define the OP of SEE for SWIPT-in-DAS.

Development of self-cleaning bricks surfaces by CaCO3modified nano-TiO2 composite coatings

Recently, many studies have been carried out on self-cleaning characteristic because it is being regarded as one of the most interesting topics in biomimicry because of its potential applications in energy conversion, and biomedical and environmental protection. In this study, spin coating process has been introduced to coat bricks surfaces with TiO2 nanoparticles based polymer composite coatings modified using CaCO3 particles for self-cleaning and environmental purposes. The matrix solutions were prepared from Polystyrene. Particle size analyzing PSA and x-ray diffraction XRD were employed for characterization of the particles. The coatings were characterized by SEM and AFM techniques, and contact angle measurement CA. Results proved that CA increased with the increasing of PS ratio and additions of nano-TiO2 and CaCO3.The composite coatings have dense topography with roughness increased with increasing of the CaCO3 addition, and porous morphology characterized by clear distribution of the nano TiO2 particles and larger CaCO3 modification particles. Also, it could be concluded that the %20PS/%6TiO2/1gCaCO3 coatings, could give promised effect in modification of bricks surfaces from superhydrophilic substrates to Superhydrophobic with higher contact angle 167.3987°. This results will encourage the future research in surface engineering of bricks surfaces using CaCO3 particles for self-cleaning and environmental applications.

Minimum achievable rate maximised resource allocation for relay‐assisted massive MIMO systems with SWIPT

This paper considers a relay-assisted massive multiple-input multiple-output (MIMO) downlink system in which a base station (BS) communicates with all terminals via a relay node enabled simultaneous wireless information and power transfer (SWIPT). Both time-switching (TS) and energy-splitting (PS) protocols are respectively considered at the relay node for coordinating energy harvesting and information decoding. The quality-of-service (QoS) fairness problem among terminals is investigated in the considered systems. In detail, the power allocation coefficients and energy harvesting time duration for TS based SWIPT, and the power allocation coefficients and PS ratio for PS based SWIPT are jointly optimised, aiming at seeking to maximise the minimum achievable rate over all terminals. As the formulated problems are non-convex and non-linear, and hard to solve directly, suboptimal heuristic algorithms are proposed for solving them. Additionally, the convergence and complexity of the proposed algorithms are also analysed. Finally, the performance of the proposed algorithms is demonstrated by extensive computer simulations. Results manifest that the proposed algorithms can provide uniformly great QoS for every terminal by resource allocation.

Gemcitabine plus nab-paclitaxel versus gemcitabine alone in elderly patients aged 76 years or older with unresectable pancreatic cancer: A propensity score-matched multicenter prospective observational study.

4123 Background: Gemcitabine plus nab-paclitaxel (GN) demonstrated a significant improvement of OS over gemcitabine alone (G) in the MPACT trial for metastatic pancreatic cancer. However, since patients aged 75 years or older was less than 10% in the trial, data for the efficacy and safety of GN in that population have been limited. Methods: We prospectively enrolled patients who were 76 years or older if they had pathologically proven, clinically unresectable pancreatic cancer and no prior history of chemotherapy. Treatment regimen was based on physicians' choice. The primary endpoint was OS and secondary endpoints included PFS, objective response, and safety. Geriatric assessments including G8, IADL, CCI and Mini-COG were performed at the time of registration and 3 months after. To adjust confounding factors in the comparison of GN and G, propensity score-matched analyses were performed. Results: We enrolled 233 eligible patients from 55 centers in Japan between September 2018 and September 2019. GN, G, other therapy, and BSC were administered to 116, 72, 29 and 16 patients, respectively. With propensity scores adjusted for age, sex, clinical stage, ECOG PS, CA19-9, and neutrophil-lymphocyte ratio, 42 patients each in GN and G were compared. Patients characteristics in the matched pair were well-balanced; median age, 79/79 years; ECOG PS 0, 43/36%; stage IV, 69%/64%. With a median follow-up of 14.8 months and 50 observed deaths, OS in GN showed a longer tendency than that in G: 12.2 vs. 9.4 months in median with a hazard ratio (HR) of 0.65 (95% CI, 0.37-1.13; p= 0.120). PFS in GN was significantly longer than that in G: 9.2 vs. 3.7 months in median with a HR of 0.38 (95% CI, 0.23-0.64; p= 0.0002). The objective response rates were 29% and 11% ( p= 0.082), and the disease control rates were 81% and 61% ( p= 0.088), respectively. Decline of G8 scores at 3 months was observed in 35% and 28% of patients in GN and G, respectively ( p= 0.610), and that in IADL scores was observed in 61% and 37%, respectively ( p = 0.194). GN had higher incidence of adverse events than G though all were not statistically significant: grade 4 neutropenia (23%/8%); grade 3-4 malaise (13%/8%), fatigue (15 %/10%), peripheral sensory neuropathy (5%/0%). The incidence of the other adverse events was comparable between GN and G: grade 4 leucopenia (3%/5%) and thrombocytopenia (0%/3%); grade 3-4 nausea (3%/5%), vomit (3%/5%) and febrile neutropenia (0%/0%). Treatment discontinuation due to adverse events was more often in GN than G (39%/14%). Conclusions: Our data suggests GN is more efficacious than G even in patients aged 76 years or older, although GN have higher incidence of grade 3-4 adverse events and tends to decrease geriatric assessment scores. Clinical trial information: UMIN000034265.

Secrecy Outage Minimization for Wireless-Powered Relay Networks With Destination-Assisted Cooperative Jamming

To solve security vulnerability and energy scarcity problems in relay, we propose two secure relaying protocols, power splitting-based relaying (PSR) and time switching-based relaying (TSR), in a wireless-powered relay network with destination-assisted cooperative jamming. In these protocols, the relay adaptively controls the amount of energy harvested from the received signals using PS or TS policy, considering information leakage to the eavesdropper. We first prove the convexity of the secrecy outage probability with respect to the PS ratio ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\rho $ </tex-math></inline-formula> ) and TS ratio ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> ), and then derive the closed-form expressions of the optimal <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\rho $ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> for minimizing secrecy outage under the signal-to-noise ratio (SNR) assumption. Numerical results reveal that the proposed PSR and TSR protocols using the derived <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\rho $ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> can achieve near-optimal performance in terms of secrecy outage. It is observed that the optimal <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\rho $ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> do not depend on the eavesdropping channels in a high SNR regime such that the near-optimal secrecy outage can be achieved practically without knowledge of the eavesdropper location. Furthermore, intensive simulations reveal that it is advantageous to allocate more power to energy harvesting for PSR, whereas more time to signal processing for TSR to minimize secrecy outage.

Weathering effects on the thermal conductivity of PS/PMMA blends for packaging application

This work describes the weathering effects (UV-Irradiation, and Rain) on the thermal conductivity of PS, PMMA, PS/PMMA blend for packaging application. The samples were prepared by cast method at different ratios (10, 30, 50, 70, and 90 %wt). It was seen that the thermal conductivity of PMMA (0.145 W/m.K), and for PS(0.095 W/m.K), which increases by PS ratio increase up to 50% PS/PMMA blend then decreased that was attributed to increase in miscibility of the blend involved. By UV-weathering, it was seen that thermal conductivity for PMMA increased with UV-weathering up to (30hr) then decreased, that was attributed to rigidity and defect formation, respectively. For 30%PS/PMMA, there results showed unsystematic decrease in thermal conductivity, which was attributed to unsystematic degradation. By Rain-weathering, thermal conductivity PS, PMMA, and 30 %PS, PMMA, it was seen systematic decreased in PS and 30 % PS/PMMA thermal conductivity; and systematic decrease in PMMA thermal conductivity. That due to the water diffusion in the samples that created some voids, bubbles, and results in decrease in thermal conductivity. This result was attributed to the decrease in adhesive between the components of polymer systems. The results suggested that the samples involved could be used for packaging application.

Development of vanillin/β-cyclodexterin inclusion microcapsules using flax seed gum-rice bran protein complex coacervates.

Encapsulation of vanillin through β-cyclodexterin inclusion complex coacervates (β-CD-IC) was developed to achieve higher thermal stability and controlled release of vanillin. The effect of protein to polysaccharide (Pr:Ps) ratio and core (Vanillin/β-CD-IC) to wall (coacervate) ratio on the vanillin encapsulation as well as thermal, microstructural and physical characteristics of microcapsules were investigated. Microcapsules had particle size ranging from 0.75 to 4.5 μm with negative surface charge and narrow size distribution. Although particle size and encapsulation efficiency were increased by increasing the Pr:Ps ratio and core to wall ratio, the zeta-potential decreased. Vanillin/β-cyclodexterin loaded microcapsules had the maximum encapsulation efficiency about 85% at core to wall ratio of 1:3 and Pr:Ps ratio of 9:1. Structural studies by Fourier-transform infrared spectroscopy (FTIR) indicated the entrapment of encapsulant and X-Ray diffraction data and scanning electron microscopy (SEM) images showed that microcapsules have amorphous structure with soft surface. Furthermore, FTIR results indicated the formation of vanillin/β-cyclodextrin inclusion is the result of chemical interactions, but physical interaction between core and shell leads to encapsulate vanillin/β-cyclodextrin inclusion in rice bran protein-flaxseed gum (RBP-FG) coacervates. Microencapsulation increased the vanillin thermostability and its shelf life. Therefore, it is possible to increase thermal stability of vanillin against environmental conditions.

Wireless Powered Cooperative Communication Using Two Relays: Protocol Design and Performance Analysis

This paper develops an adaptive cooperative transmission scheme with relays harvesting wireless energy. Two relays are adopted to alternately forward source data to the destination using the two-path successive relaying (TPSR) protocol. When one relay forwards previous data along with source transmitting current data, using the power-splitting technique, the other relay will harvest energy and decode the current data from the received composite signal. If the TPSR cannot be performed due to the failure of data decoding at either relay, the decode-and-forward (DF) protocol will be performed by selecting a better relay. If one relay joins in the DF relaying, it will harvest energy and decode source data using the PS technique, while the other relay will always harvest energy from the received signal. If neither TPSR nor DF relaying can be performed, the source will transfer wireless power to both relays. The transmit powers of relays and the PS ratio are judiciously determined through analyzing the occurrence probability, average power fading, and success probability of each case. Numerical results show that our adaptive relaying scheme can achieve a much higher throughput than the single-relay DF scheme and the TPSR-only scheme.

Dynamic Power Splitting Strategy for SWIPT Based Two‐Way Multiplicative AF Relay Networks with Nonlinear Energy Harvesting Model

This paper investigates an energy‐constrained two‐way multiplicative amplify‐and‐forward (AF) relay network, where a practical nonlinear energy harvesting (NLEH) model is equipped at the relay to realize simultaneous wireless information and power transfer (SWIPT). We focus on the design of dynamic power splitting (DPS) strategy, in which the PS ratio is able to adjust itself according to the instantaneous channel state information (CSI). Specifically, we first formulate an optimization problem to maximize the outage throughput, subject to the NLEH. Since this formulated problem is nonconvex and difficult to solve, we further transfer it into an equivalent problem and develop a Dinkelbach iterative method to obtain the corresponding solution. Numerical results are given to verify the quick convergence of the proposed iterative method and show the superior outage throughput of the designed DPS strategy by comparing with two peer strategies designed for the linear energy harvesting (LEH) model.

Can long chain n-3 fatty acids from feed be converted into very long chain n-3 fatty acids in fillets from farmed rainbow trout (Oncorhynchus mykiss)?

The link between the basic chemical and fatty acid composition of trout feed on one hand and trout (Oncorhynchus mykiss) meat (fillet) was investigated.. The content of 52 fatty acids from feed and trout meat lipids was determined by in-situ transesterification and capillary column gas-liquid chromatography. On average, 100 g of trout feed contained 7.4 g of moisture, 47.7 g of proteins, 6.09 g of ash, 21.4 g of fat, and as for fatty acid composition, 47.8 wt. % were monounsaturated, 34.0 wt. % were polyunsaturated and 18.1 wt. % were saturated fatty acids, with the PS ratio 1.88, n-6/n-3 ratio 1.74, 0.80 wt. % of trans and 3.28 wt. % of very long chain n-3 fatty acids. On average, 100 g of trout meat contained 76.1 g of moisture, 21.4 g of proteins, 1.34 g of ash, 2.52 g of fat, and in the fatty acid composition 42.1 wt. % were monounsaturated, 38.2 wt. % were polyunsaturated and 18.9 wt. % were saturated fatty acids, with the PS ratio 2.02, n-6/n-3 ratio 0.98, 0.95 wt. % of trans and 13.25 wt. % of very long chain n-3 fatty acids.

Clinical Significance of Mean Platelet Volume Determination in Multiple Myeloma

To investigate the clinical significance of mean platelet volume(MPV) in patients with multiple myeloma(MM). The clinical data of 198 patients with MM admitted in our hospital from March 2008 to March 2015 were collected and analyzed. The clinical data included the Ig type, hemoglobin level, platelet count, creatinine, calciumion albumin, β2-MG, LDH, plasmocytes in bone marrow, MPV, complications such as diabetes, a history of venous thromboembolism (VTE) and arterial events such as coronary artery disease, cerebrovascular disease, thrombosis and blood clotting. All patients were divided into low MPV group (≤8.50 fl) and high MPV group (>8.50 fl). The biochemical parameters and prognosis of the 2 groups were compared. When MPV was 8.50 fl, the higest sensitivety and specificity were 55.56% and 80.00% respectively. The area under curve (AUC) was 0.656 (95% CI: 0.515-0.797), the IgA type, creatinine level and IgH rearrangement in MM patients were related with MPV. The ratio of IgA and IgH rearrangements in patients with low MPV was higher than that in patients with high MPV, and the ratio of patients with creatinine >176.8 µmol/L was lower than that of patients with high MPV (P<0.05). The age, sex, ECOG PS, complications, ISS stage, hemoglobin level, platelet count, calcium ion, albumin, β2 microglobulin, lactate dehydrogenase and bone marrow plasma cell ratio were not statistically significantly different between the 2 groups. Patients with low MPV had a shorter OS (P=0.039) than those with higher MPV. Univariate analysis showed that MPV, BM plasma cell ratio and age>60 years correleted with OS. Multivariate analysis showed that the low MPV and BM plasma cell ratio were correlated with shorter OS (P<0.05). The low MPV is correlated with poor prognosis in patients with MM and may serve as an important indicator for disease progression and prognosis of patients with MM.

P‐81: Influence of Photo‐Spacer Ratio on Yellow Spots and Ripple on a 5.5‐in. Halftone‐Mask Panel

We conducted experiments to test the influence of photo spacer PS on yellow spot and ripple. Results showed that the severity level of yellow spot and ripple can be lessened when main PS ratio reached more than 0.1%. Additionally, other PS parameters were further discussed.

Systematic Studies of Distributed and Hybrid Raman Amplification in 10G-EPON and TWDM-PON

AbstractWe have studied distributed Raman amplification (DRA) and hybrid Raman amplification to apply both 10G-EPON and TWDM-PON systems. Two types of access networks, 50 km and 10 km, are assumed for case studies. Using the calculated optical received signal power Ps and optical signal noise ratio (OSNR), we consider the cases where the hybrid Raman amplification is necessary or not. In the case of coexistence of both systems, co-use of lumped Raman amplification (LRA) located at a central office (CO) may be possible. The co-use of LRA for both systems is discussed using the calculated Ps and OSNR.

Wireless Information and Power Transfer in Multiuser OFDM based Systems

In this paper, we have study the optimal design for synchronous wireless information and power transfer (SWIPT) in downlink multiuser orthogonal frequency division multiplexing (OFDM) systems, where the users gather energy and explain information by using the same type of signals received from a stable access point (AP). For the transmission of information, we have to consider two types of numerous access patterns, called, time division multiple access (TDMA) and orthogonal frequency division multiple access (OFDMA). Beneath the above two scenarios, we locate the problem of maximizing the weighted sum-rate overall users by varying the time or frequency power arrangement and either TS or PS ratio, subjected to a minimum harvested energy constraint on each user as well as a highest and or overall transmission power constraint.. It is revealed that the highest power constraint inflict on each OFDM SC as well as the number of users in the system play basic roles in the rateenergy performance comparison by the two types of proposed arrangements.

Fabrication and characterization of bamboo fiber- reinforced polyethylene-polystyrene composites using glycerol as plasticizer

&lt;p&gt;Fiber-reinforced polymer composites are composed of a polymer matrix (PE-PS) combined with a fiber (bamboo fibers) to provide conspicuous reinforcement. In light of recycling plastic and natural fibers, the research aim to fabricate and characterize bamboo fiber-reinforced polyethylene-polystyrene composites using glycerol as plasticizer. Specifically, the study investigated the effect on the physical and mechanical properties and water absorption of the composites by varying the following parameters: substitution of glycerol instead of the usual cooking oil in fabrication of DRM, and bamboo fiber loading. Using 1:3 PE-PS ratio, glycerol incorporation was done in DRM by melting together plastic and styrofoam wastes using a densifying machine at 150˚C. DRM samples with 70% (w/w) glycerol incorporation were then compared to the original DRM samples with 70% (w/w) cooking oil. The modified DRM were then loaded with 1, 2 and 3% bamboo fiber-reinforcement using a two-roll mill at 200˚C and compression molding machine at 200˚C and 50 kg/cm2 for 5 mins in the aluminium mold. The composites were characterized by Universal Testing Machine (tensile strength) following the ASTM standard D638. In addition, water absorption of the fabricated composites was tested using the standard method specified by ASTM D570.The bamboo fiber-reinforced polyethylene-polystyrene composites at 1:3 PE: PS ratio rendered better tensile strength and less water absorbed using 70% (w/w) glycerol as plasticizer and at 1% bamboo fiber loading. For future studies, it is recommended to study the impact of different parameters (glycerol percentage, time, temperature, pressure, fiber type and dimensions, fiber extraction, etc.) in the fabrication of the fiber-reinforced recycled plastic composites. Other characterizations of the fabricated plastic composite including thermal properties, leaching and biodegradation experiments and compressive and flexural strengths can also be done.&lt;/p&gt;&lt;p&gt;Keywords: Fiber-reinforced polymer, plasticizer, composites.&lt;/p&gt;

Passive harmonic mode-locking of Er-doped fiber laser using CVD-grown few-layer MoS2 as a saturable absorber**Project supported by the National Natural Science Foundation of China (Grant Nos. 61378028, 61421002, 61475030, and 61377042), the National Basic Research Program of China (Grant No. 2012CB315701), and the New Century Excellent Talents Program in University, China (Grant No. NCET-13-0092).

Passive harmonic mode locking of an erbium-doped fiber laser based on few-layer molybdenum disulfide (MoS2) saturable absorber (SA) is demonstrated. The few-layer MoS2 is prepared by the chemical vapor deposition (CVD) method and then transferred onto the end face of a fiber connector to form a fiber-compatible MoS2 SA. The 20th harmonic mode-locked pulses at 216-MHz repetition rate are stably generated with a pulse duration of 1.42 ps and side-mode suppression ratio (SMSR) of 36.1 dB. The results confirm that few-layer MoS2 can serve as an effective SA for mode-locked fiber lasers.