The solid-liquid two-phase flow centrifugal pumps are widely applied in reality, but the complicated flow in pump makes plentiful of flow rules not be completely revealed so far. Theory research and design method concerning them aren't very mature, so low efficiency, more abrasion and poor reliability always universally occur. To enhance design capability of two-phase flow pump, two-phase flow behavior of 3-D flow field requires to be completely mastered. At present, large numbers of researches mainly focus on a designated geometry relative position between impeller vane and volute tongue, while these flow characters of different relative positions don't be research in detail, especially two-phase flow pump. The mathematical model of 3-D flow field of two-phase flow centrifugal pump is established by using the computational fluid dynamics(CFD)theory in the paper. In calculation region, multi-block mesh technology and local mesh refinement technology...............

Keywords - Two-phase flow; centrifugal pump; numerical simulation; experimental research

The purpose of this article is to investigate the influence of temperature on the mechanical behavior of acrylonitrile Butadiene Styrene from a wide range of uniaxial tensile tests conducted from room temperature in the laboratory (22 ° C) to at 180 ° C, near the melting temperature (195 ° C). Knowledge of the mechanical behavior is essential to predict the life of the components in order to avoid any sudden interruption of service. In this context, our study aims to predict the life span and know the limits that must not be exceeded, namely the identification of the three stages of damage: initiation, progression and sudden acceleration. The estimation of the degree of damage by the model of static damage leads to the theoretical identification of the three stages of damage evolution. Subsequently, a theoretical re-evaluation of the level of damage was carried out by a judicious adaptation of the theoretical model proposed in the unified theory of damage. Theoretical and experimental results showed a good agreement.

Keywords - Damage, Mechanical behavior, Polymer, Reliability, sudden rupture, Temperature, Tensile tests.

Purpose: The purpose of this study is the dosimetric comparison of 6 MV flattening filter free (FFF) and 10 MV FFF energies in the lung stereotactic body radiotherapy (SBRT) plans. Materials and Methods: The treatment plans of 16 lung SBRT patients were prepared using the same fields and the same physical parameters for 6 MV FFF and 10 MV FFF energies. Critical organ doses, planning target volume doses, quality of plans (gradient index (GI), homogeneity index of International Commission on Radiation Units and Measurements (HIICRU), heterogeneity index (HI), and conformity index (CI)), and monitor unit (MU) values have been compared.........

Keywords - FFF energies, Lung SBRT, Average Gama Index

This paper focused on predicting the future production rate of an oil well using decline curve analysis and reservoir simulation. KN well 2A was used as the case study.Based on past production history, standard curves were generated usingexponential, hyperbolic and harmonic decline model equations from which comparative study of production decline rate trend analysis was carried out. The model equations were used to project future oil productions for a period of20 years. The exponential, hyperbolic and harmonic decline models yielded cumulative production values of 1117857 bbls, 1537573 bbls and 1871021 bbls, respectively.Also, history match was performed to evaluate the production behaviour of the field.........

Keywords - Decline rate trend analysis,production forecast,history matching, reserves estimation.

Springback prediction is necessary when applying tailor welded blanks to automotive parts. The accuracy of springback prediction depends on the material model, which describes the deformation behavior of steel sheets. In each sheet metal forming process, the steels, in this case tailor welded blanks exhibit springback effect, which is governed by strain recovery of material after load removal. In this work, numerical simulation of a U-shape forming was performed on tailor welded steel strips. Two steels with different strengths were taken into account. High strength steels exhibit more distinct springback effect than steels used for deep drawing. This is mainly due to their higher values of Yield strength. Springback is related to many parameters like forming conditions, tool geometry and material properties such as sheet thickness, yield stress, work hardening, strain rate sensitivity and elasticity modulus.........

Keywords - Tailor welded blank, springback prediction, sheet metal forming, numerical simulation.

This work investigated the effect of temperature variation on the catalytic reforming process as it relates to the yields of Benzene Toluene Xylene (BTX). There is need to increase the level of Benzene, Toluene and Xylene (BTX) yield produced in the refinery and also made available for other industrial applications. The BTX are obtained froma continuous catalytic reforming process of treated heavy Naphtha samples obtained from Nigerian crude(Qua Iboe and Forcados) which are readily available in large quantities.The catalytic reforming process was simulated using Aspen Hysyswhile varying the temperatureof thereactors between 430 – 520oC while the outlet concentrations of BTX (Vol.%) produced were measured. An increase in temperature led to an increase in the concentration of BTX produced...........

Keywords - Benzene,Continuous Catalytic Reforming,Forcados Blend, Qua Iboe, Temperature, Toluene, Xylene.

Untreated effluents may also contain dyes, especially in discharges from textile and fabric industries. Synthetic dyes have an adverse effect on all forms of life when discharged directly into the environment. This study investigates the photodegradation of Malachite Green (MG), a triaryl methane dye and the influence of initial dye concentration, pH, catalyst dose, reaction time on the overall photodegradation process. Photoreactor technique utilized was the slurry method; the photoreactor was equipped with a 15 W UV light and the photocatalyst used was nano titanium dioxide (80% anatase and 20% rutile). The results obtained showed that variation in the physical parameters influenced the efficiency of photodegradation. Kinetic study indicated that MG photodegradation follow the pseudo-first-order kinetics; 10 ppm MG gave the highest-first-order rate constant, followed by 30 ppm MG while 50 ppm MG gave the least rate constant; implying that better degradation was obtained at low MG concentration. Impact of Cu2+ ions on MG degradation was also investigated and results indicated an inhibitory effect.

Keywords - Photodegradation, synthetic dye, malachite Green, titanium dioxide, kinetics.

The stochastic dynamics and behaviour of the Nigerian Stock Market (NSM) as a whole are characterised by the daily movements of the Nigerian All Share Index (NASI). By using the Rescaled Range Statistics (R\S) to classify the time series, the Hurst parameter, H, was obtained in order to characterise the NSM in the form of an exponential fractional Brownian motion (fBm). The covariance, ( , ) H R t s , of the exponential fBm of the NASI was obtained in an unbiased long range dependence (LRD) phenomenon with H > 0.5.

Keywords - Nigerian All-Share Index, Hurst Parameter, Covariance, Exponential Fractional Brownian motion, Long Range Dependence.

The study area, Lokoja river bank has been under the effect of flood for some time now, to study the effect of the floods on man and the environment, soil samples were collected along the river bank for analysis. 10 soil samples were collected from 10 locations for analysis at the Civil Engineering Department of Kogi State Polytechnic, Itakpe Campus. The Engineering properties of soil analyzed for are moisture content, particle size Distribution, compaction, specific gravity, consistency limit of the soil such as plasticity, liquid and plastic index. The result shows that the soil grain sizes ranges from medium-coarse grain (0.2 to 2mm) on sieve no 200. Samples at location 6 and 9 which is mainly medium grain sand have liquid limit (LL) of 19.3% and 23.0% which are good for construction, while sands obtained at other location have LL that ranges from 24. 0% to 44.0% which are not suitable for construction

Keywords - Flood, Environment, Engineering Properties, Soil

This paper proposes a new meta-heuristic search algorithm, called Novel Bat Algorithm (NBA). The proposed algorithm combines the bats' habitat selection and their self-adaptive compensation for Doppler effects in echoes into the basic bat algorithm (BA). The selection of bats' habitat is modeled as the selection between their quantum behaviors and mechanical behaviors. The new algorithm is implemented to solve Environmental/Economic power Dispatch (EED) problem in power systems considering the power limits, valvepoint effects and transmission loss. The EED problem can be solved by summing up the minimization of generation cost and emission by considering weighting factor. The effectiveness of the proposed algorithm has been tested on 10-unit system and the results were compared with other methods reported in recent literature.

Keywords - Novel bat algorithm, economic dispatch, emission dispatch, environmental economic dispatch, valve-point effects.

In this study, we investigate the effect of geometric layout features of mobile-phone keypads, such as the column-row location, the key width, the key-center distance, and so on, on key-pressing time when a mobile phone is held in one hand and the thumb is used to press the keys. During this study, six participants in the experiments used their dominant right hand to operate keys of three different widths, viz., 2, 6, and 12 mm. In the keypads, as in the standard mobile-phone-keypad layout, there are three vertical columns and four horizontal rows in the keypad; the distances from the center of one key to the next in the vertical/column direction are 12, 24, and 36 mm, while in the horizontal/row direction, they are 15 and 30 mm. The key-pressing performance was measured by the key-pressing movement time.

Keywords - Mobile phone, keypad, Fitts' Law.

In the present study, the extracts of Nigella sativa seeds were prepared by Soxhalate, Hot and Cold extraction methods using water and methanol as solvent. The free radical scavenging activity of all extracts were investigated by DPPH (2,2-diphenyl-1-picrylhydrazyl). The super coiled pBR322 plasmid was used to study the protection of DNA against H2O2 - induced oxidative damage. Antimicrobial activity of each extract was determined by Well Diffusion method. The results of DPPH and DNA damage assay revealed that methanol is better solvent than water and the Soxhalate method and Hot extraction methods are effective techniques to get antioxidant rich extract. Methanolic extract prepared by Soxhalate method showed activity against E. coli. The extract obtained by cold extraction technique showed positive antibacterial activity and least antioxidant activity.

Keywords - Antimicrobial activity, Antioxidants, DNA Damage , DPPH

Safety is the highest priority of nuclear power plant operation. Nuclear power plants are designed with the safety in mind, while taking into account the anticipated operational occurrences and accidents. Despite the low probability of these events occurring, it is important to have the safety systems, strategies, trained operators and durable equipment in place. The safety systems and equipment have to stay functional during normal operation, but also under harsh conditions, that may occur in case of an accident. Equipment that is essential for safety systems and may be subjected to harsh conditions have to be tested and subsequently qualified to ensure their long-time durability. The process of testing involves subjecting the equipment to harsh conditions, comparable to a real accident. The purpose of LOCA Laboratory is simulation of harsh conditions of Loss of Coolant Accident. The laboratoryis used in development process of new equipment for current and future generations of Nuclear Power Plants.

Keywords - ...........

Managing risks in infrastructure construction projects has been recognized as a very important management process in order to achieve the project objectives in terms of time, cost, quality and scope. This paper aims to identify and analysis of risks associated with the infrastructure projects. Based on a comprehensive assessment of conditions of contracts, this paper identifies risks and classifies them into eight types. It is observed by qualitative risk analysis, opposition from social bodies, changes in design and suspension of work are recognized to influence the project objectives maximally.This study has been found that few suggestions to mitigate construction project risks. The contract documents are used as a tool to manage risk and client, contractors and investors need to establish risk management policy throughout the project life. It is concluded that clients, designers, contractor and government bodies must work cooperatively from the feasibility phase onward to address potential risks in time.

Keywords - Construction projects, Contract, Qualitative risk analysis, Risks, Risk management.

A unique and simple solar desalination system has been developed using humidification and dehumidification process. The system consists of humidification and dehumidification chamber. The key point is the psychrometric energy re-use, most of the energy required for the desalination process is recovered from the dehumidification chamber. A psychrometric analysis of the system is presented. Further analysis was conducted using experimental data to optimise the performance of the system. The system produced 18kg/h of fresh water using 3kW energy input. The effect of operating conditions which include flow rates and temperatures of feed water, air and cooling water are also presented.

Keywords - psychrometric, humidification, dehumidification, desalination.

This study was conducted at Adana and Antalya provinces which are in the Mediterranean coastal zone of Turkey in 2016. The study was done with 9 sweet sorghum genotypes and 4 sorghum variety in the randomized blocks design of experiment as 4 replicates. As a result of the analyses in Adana location, the juice yield was between 8728 and 35143 Lha-1, Brix value was between 13.25 and 17.38%, total sugar content was between 1245 and 5909 kg ha-1, ethanol yield was between 738 and 3146 L ha-1, sucrose content was between 8.02 and 13.89%, glycose content was between 1.73 and 2.69%, fructose content was between 1.22 and 2.78%. As a result of the analyses in Antalya location, the juice yield was between 5353 and 37018 L ha-1, Brix value was between 11.08 and 17.73%, total sugar content was between 612 and 6381 kg ha-1, ethanol................

Keywords - Bioethanol, brix, sorghum, sugar.

In this paper, root supermultiplicities and corresponding combinatorial identities for the Borcherds superalgebras which are extensions of n A and n B were found out.

Keywords - Borcherds superalgebras, Colored superalgebras, Root supermultiplicities.

Trawling fishing equipment that has been banned from operating under Presidential Decree 85 of 1982 chose to use cantrang which is a modification of trawling as an alternative which was then banned from being used by the government so that the minister of maritime affairs and fisheries was issued to extend the use of cantrang fishing gear. The purpose of this study is to determine the performance and productivity of the ship along with profit and loss during the operating period. Catching method using trawling with 0-21 up GT ships. Sales results use a profit sharing system. The most caught fish species are common ponyfish (Leiognathus sp) of 1,200 kg and golden-threadfin bream (Upeneus vittatus) 867 kg. The gross profit earned is divided into 25 parts. The 21 up GT ship has greater productivity with an average yield of 63,453 kg.

Keywords - Fishing Gear, Profit, Productivity

The presents high cost of construction materials in the country calls for alternatives which will also be appropriate for construction works and as well achieved the desired strength. The study reports on experimental investigation on the utilization of blast furnace slag (BFS) as full replacement for crushed granite in concrete production. Two control mixing ratios of 1 : 1½ : 3 and 1 : 2 : 4 batched by weight with water – cement ratio of 0.55 were used. The slump test was used to assess the workability of the fresh concrete. The compressive strengths and densities of cured concrete cubes of sizes 150mm x 150mm x 150mm were evaluated at 7days, 14days, 21days and 28days. A total of forty – eight (48) concrete cubes were cast and tested. The full replacement of crushed granite with blast furnace slag lowered................

Keywords - blast furnace slag (BFS), concrete, ordinary Portland cement, coarse aggregate, compressive strength.

Peak to average power ratio (PAPR) has become a major concern in multi-carrier-Orthogonal Frequency Division Multiplex (OFDM) application. The PAPR in OFDM transmitter causes efficiency reduction of RF power amplifier. Several mitigation approaches have been proposed in the literature for the OFDM system. Most of these approaches suffer from lack of high PAPR performance or complexity. In this paper, some of the most significant features of OFDM such as cyclic prefix, spectral efficiency and orthogonality of multi-carrier OFDM have been described. Also, presented a mathematical expression to model the OFDM transmitter using linear and nonlinear RF power amplifier to analyze the best performance of the system with different modulations. The simulation results demonstratedthe BER performance of the multi-cattier OFDM transmitter system with and without power amplifiers.

Keywords - Multi-carrier OFDM, PAPR, Cyclic Prefix, BER Performance.

In the newest high efficiency video coding (HEVC) standard, the motion estimation (ME) takes around 70% of the encoding time in HM encoder. In order to reduce the complexity of the ME module in HEVC, this paper proposes a flexible coding tree unit (CTU)-level parallel ME method usinga graphics processing unit(GPU). The proposed method can be combined with fast CTU-level multiple reference frame motion estimation (MRF-ME) to further reduce the encoding time. Firstly, we decompose ME algorithm into threekernels to achieve a highly parallelcomputation with a low external memory on GPU. Secondly, the kernel 1 executes a GPU program of calculating the sum of absolute differences (SAD) of small coding unit (SCU 88).................

Keywords - Video coding standard, HEVC, GPU, Motion estimation.

Skipjack tuna (Katsuwonus pelamis) is a superior economic activity in the North Sulawesi fisheries sector, which is usually captured by pole and line. To increase the efficiency of fishing with pole and line, it is necessary to know the number of relationships between the number of live bait distributed with the catch MV. Venio 07 belongs to Sari Usaha Mandiri. Ltd Bitung North Sulawesi for 8 times sailed dividing the fishing operation area into two fishing ground (fishing ground), that is Maluku Sea and Sulawesi Sea. The composition of fish catches Pole and Line is Skipjack tuna (Katsuwonus pelamis) 63,050 kg and Yellowfin (Thunnus albacares) 19,900 kg.................

Keywords - Pole and line, living bait.