The internet brought a diffusion of technology in the banking arena. Two of the personal devices which aid this phenomenon are the computer (website) and smartphone (web application). Nowadays, banking is done vividly through the internet that causes both computer and smartphone prone to security risks. This review paper aims to highlight the earlier research deliberations, suggested solutions and the factors related to security issues in electronic banking devices in the past six years. Narrative literature review method was used by reviewing 130 papers from selected database journals. The paper discusses the articles between the years 2012 and 2018. It points and poses unanswered questions, which serve as the scope for further research. Neither a computer nor a smartphone has an upper hand when it comes to security. Security of banking technology does not depend on these devices. Rather the onus rests on the users, service providers and banks. The emerging electronic commerce and mobile commerce industry are not considered in this paper. This paper endeavours to provide a better scope for researchers in future to answer unrequited questions on the role of devices in banking technology security. All the past literature has focused on the peoples' attitude towards security threats in online banking. This study challenges to think further, about the influence of security threats to online banking devices.
Internet banking, mobile banking, privacy, review, risk, security, trust
Given the increasing number of applications requiring high data transmission, this is the reason for the use of high order constellations such as Quadrature Amplitude Modulation (QAM). However, communication systems using QAM require a high signal to noise ratio. To overcome this disadvantage, it is interesting to combine high error correction codes such as Low-Density Parity-Check (LDPC) codes with QAM. Although the LDPC codes are good codes for a system using QAM, concatenation of these codes with iterative decoding is still attractive to construct more powerful codes. In this context, we propose the non-binary serial turbo LDPC code. It is obtained by a serial combination of two identical regular non-binary LDPC codes, separated by an interleaver introducing the diversity. Regular codes were used to avoid the complexity of irregular codes despite that they have better performance than the regular code. Simulation results show that the performance of non-binary serial turbo LDPC code, with 16-QAM, 64-QAM and 256-QAM constellations using Gray mapping under Gaussian and Rayleigh channels, are higher than that of non-binary LDPC codes.
Iterative decoding, Low-Density Parity-Check codes, non-binary, serial concatenation, turbo-code
Corn production is second to rice as the most important agricultural product in the country. Thus, proper information, management, and technology dissemination in corn farming are greatly needed for a good harvest. The study aims to develop a mobile application to comprehensively address the needs of corn farmers thru dissemination of proper information, management, and techniques through the cooperation of the City Agriculture Office (CAO) of Malaybalay City, Bukidnon, Philippines. It is anchored on the Unified Theory of Acceptance and the Use of Technology (UTAUT) Model, where there are core and direct determinants of user reception and usage behavior, as well as moderating factors on user's acceptance on mobile services and applications especially in the area of agriculture. The researchers use the method of "Modified Waterfall Model" or MWF Model as the process model for the development of Ma-Ease Application. The sequential structure of this approach ensures that all requirements are achieved before moving onto the next step and no important steps are left out in the development process. A presentation was conducted with the CAO Malaybalay officials and local corn farmers to introduce our technological solutions in the corn production like local and up-to-date weather updates, proper nutrient inputs and corn farming activities, efficient cost management, and control of corn pests and diseases. Effectivity tests were done during their actual interaction and engagement with the finished product and finding shows that the Ma-Ease mobile app has a grand mean of 4.175 for its acceptability and satisfaction rate which covers the area of functionality, reliability, usability, maintainability, efficiency and user interface. Thus, the software product was formally accepted and recommended for use and deployment by the Department of Agriculture (DA).
Corn farming mobile application, corn farming software solution, corn management, corn production, ICT in agriculture, ICT in corn farming, technofarm, technology in corn farming
MSME is a business group of society that does not have an integrated system like a large industry which makes it difficult to access information toward the location of foreign markets. This study develops Market Matching application to determine the location of foreign marketing and the type of products that must be exported to reduce the number of losses due to the congestion of turnover of goods to make it profitable for MSME. Stages to develop this market matching system are the identification and analysis of ongoing export marketing activities in MSME, designing marketing system that fits the analysis, establishing market matching system, and system implementation. This study proposes fuzzy control to determine the number of export and export market destination. Market matching application obtained recommendation of export destination based on the types of product and level of importer need. This study obtained the system's accuracy in 100% range.
Economy, fuzzy control, market matching, Micro Small Medium Enterprises (MSME)
Supervised clustering organizes data instances into clusters on the basis of similarities between the data instances as well as class labels for the data instances. Supervised clustering seeks to meet multiple objectives, such as compactness of clusters, homogeneity of data in clusters with respect to their class labels, and separateness of clusters. With these objectives in mind, a new supervised clustering algorithm based on a multi-objective crowding genetic algorithm, named SC-MOGA, is proposed in this paper. The algorithm searches for the optimal clustering solution that simultaneously achieves the three objectives mentioned above. The SC-MOGA performs very well on a small dataset, but for a large dataset it may not be able to converge to an optimal solution or can take a very long running time to converge to a solution. Hence, a data sampling method based on the Bisecting K-Means algorithm is also introduced, to find representatives for supervised clustering. This method groups the data instances of a dataset into small clusters, each containing data instances with the same class label. Data representatives are then randomly selected from each cluster. The experimental results show that SC-MOGA with the proposed data sampling method is very effective. It outperforms three previously proposed supervised clustering algorithms, namely SRIDHCR, LK-Means and SCEC, in terms of four cluster validity indexes. The experimental results show that the proposed data sampling method not only helps to reduce the number of data instances to be clustered by the SC-MOGA, but also enhances the quality of the data clustering results.
Recommender Systems (RS) have proven to be a successful personalization technique in this era of ever increasing information overload. Among many available recommendation techniques, Collaborative Filtering (CF) is the most popularly used. However, most of the CF applications use single ratings for recommending items and the use of multi-criteria ratings in the recommendation process is still under-explored. This paper proposes multi-criteria RS based on Adaptive Genetic Algorithm (AGA). The AGA design, which updates the crossover and mutation rates dynamically, is employed to model the users' preferences for multi-criteria ratings on different attributes of items. The AGA optimizes a user's preferences for different attributes in the form of a weight vector. Thus, the AGA finds an individual optimal weight vector in relation to each user. The weight vector is used to recommend items to the respective user. The experiments are conducted on Yahoo movies, a well-known multi-criteria rating dataset. The experimental results confirm that the AGA based multi-criteria RS outperforms the traditional single criteria based Collaborative Filtering RS and the simple GA based multi-criteria RS.
Collaborative filtering, Genetic Algorithms, multi-criteria, Recommender Systems
This smart appliances project is intended to create home appliances which are able interconnect one another and share data to provide convenient and comfortable environment to users. For this project, we successfully developed a smart food cabinet with the abilities to perform several things such as giving information about the items stored within the smart food cabinet to its users via a mobile application. By using the information, the users contact the store to order the items needed. The food cabinet takes the data from the smart cabinet about the items and combine them to its own data to give information about recipes selection according to the availability of the items in both smart food cabinet and refrigerator. The system is built based on Arduino and Raspberry Pi, and the results shows that the recipes displayed in the LCD are according the availability of the items. The information can be accessed via Android based application in a smartphone.
Data sharing, smart appliances, smart cabinet, smart home, smart refrigerator
The cloud is storing a huge amount of the data, including personal and confidential details. It involves the third party over the internet and proposes many unreliable strings which can be proven as loopholes. Thus, securing the data in the cloud tends to be a major point of concern. SQL Injection Attacks (SQLIAs) are being acknowledged as one of the foremost web applications security threats. It initiates a vulnerable query to destroy the connected server systems and help attackers with unauthorized access to the databases resulting in identity theft and security violations. The paper proposes a hybrid solution whose information utility is higher than the solutions that are being proposed earlier. As the methodology is concerned over static, dynamic and runtime detection and prevention mechanism. It also classifies the malicious queries and inspires the system to be well prepared for the secure working environment by implementing a demonstration design. Through the experimental implementation, the query associativity makes success probability of 0.775 using the associativity formula that in fraction, results in a durable comparative solution proposed till date.
Nowadays internet has become indispensable part of one's life. Therefore, security and privacy are of critical concern to retain user's confidence in network services and applications. Several password verification based schemes/protocols have been used for authentication over insecure channel to protect resources from unauthorized access in networked environment. However, the schemes were not fault tolerant. Also, the feasibility for implementation in some of the applications was questionable. Therefore, we have devised a scheme SPAS (Secure and Provable Authentication Scheme) to overcome the issues prevalent in existing schemes. The objective was to keep the computational and communication cost low. The analysis of the presented scheme SPAS over existing schemes corroborates its effectiveness in tackling various attacks and uniqueness. Further, the performance analysis of the presented scheme is also given to strengthen the proposal.
This research was conducted to investigate the compaction performance and mechanical strength of compacted urea fertilizer in unlubricated and lubricated die systems. The ground urea 46% N fertilizer was compacted in a 13 mm flat-face cylindrical die set in both unlubricated and lubricated die systems with vegetable fatty acids and magnesium stearate as lubricants at various compaction stresses to produce urea fertilizer tablets. In conclusion, a lubricated die system reduces the frictional effects during the production of urea fertilizer tablets and also produces a mechanically stronger urea fertilizer tablet than those produced in an unlubricated die system. In addition, the vegetable fatty acids and magnesium stearate lubricants are found to improve the compaction performance of urea fertilizer tablet as well as its mechanical strength.
Ejection, fertilizer, lubricant, mechanical strength, uniaxial die compaction, urea
Competition for limited available water for crop production is an ever-increasing issue for farmers due to increasing demand of irrigation water worldwide. Due to high energy cost in operating pressurized irrigation systems, energy-efficient low-pressure wick irrigation systems can play important roles for smallholder greenhouse crop production by ensuring higher water use efficiency than most traditional approaches. The objectives of this study were to investigate HYDRUS 2D-simulated water distribution patterns in soil and soilless growing media, and to evaluate water balance in these media under capillary wick irrigation system. To accomplish these objectives, eggplants (Solanum melongena L.) were grown in potted peatgro and sandy clay loam in a greenhouse experiment, water distribution was simulated by using HYDRUS 2D software package and compared with the measured values, and water uptake by the plant roots was determined for water balance calculation. The wetting pattern was found axially symmetric in both growing media (peatgro and soil) under the wick emitters. The simulated water distribution in both growing media revealed dependency of spatial extent of the wetted zone on water application period and hydraulic properties of the media. The mean absolute error (MAE) in water content over depth varied from 0.04 to 0.10 m3 m-3 and the root mean square error (RMSE) varied from 0.04 to 0.11 m3 m-3. Deviations between the measured and simulated water contents in the peatgro medium were larger over depth than over lateral distance. In contrast, the model criteria matched well for the sandy clay loam and provided MAE of 0.01 to 0.02 m3 m-3 and RMSE of 0.01 to 0.03 m3 m-3, indicating good agreement between the measured and simulated water contents.
Numerical modeling, water balance, water distribution, Wick irrigation
Cogeneration systems are extensively used in Malaysia to produce power as a primary source. However, in the event of cogeneration system failure, the customer or the client are forced to use a redundancy to avoid power interruptions. There are two methods commonly used as a backup in the cogeneration systems which are Generator set and public utility. In order to choose the best redundancy for a particular cogeneration system, it is essential to evaluate the economic benefit analysis by considering several factors such as Maximum demand charge, installation cost and Discount interest. In the evaluation of economic benefit, this study identifies the number of failure and associated downtime using reliability and availability approach, and then present value method was applied. The result shows that the usage of public utility as redundancy is beneficial if the cogeneration system operates within five years period. However, if the cogeneration system operates more than five years, generator set option would be a better option to minimize the total cost. This research also addresses the effect of various factors such as installation cost, maximum demand charge, fuel cost, discount interest rate and production capacity. In general, the output of the research would be beneficial for the plant operator to select the appropriate redundancy option based on the economic advantages.
Cogeneration, gas turbine, public utility, redundancy, reliability
Cement Kiln Dust (CKD) is a by-product generated throughout the production of Ordinary Portland Cement (OPC). It is normally emitted to the atmosphere or converted into liquid and subsequently drained out as effluents to landfills and wastage areas. It impacted human health and the environment negatively. However, it can be utilized in concrete as raw cement replacement materials due to its engineering properties which work as an alternative binder of OPC in addition to that it has benefits in creating economic and environmental advantages. This study aimed to modify CKD and investigate the chemical composition of normal-CKD and modified -CKD accordingly. The term modified noted that CKD has gone through a process of modification using heating process. The reactivity property of CKD was investigated using pH analysis. Then, mix proportions of different percentage of normal-CKD and modified -CKD were developed to study the addition effects on the compressive and flexural strength for different curing period. The trend of strength development over the addition of CKD was also analyzed. OPC was replaced by CKD at 0% and successively increased by 10% to 100% through binder weight (OPC). A fixed amount of water to binder (W/B) with a ratio of 0.45 was used for all hybrids. The mixes were formed into the specimen and tested for compressive strength and flexural strength at 7, 14 and 28 curing days. The medium particle size of CKD used was less than 10Î¼m. The results of compressive and flexural strength showed that modified-CKD resulted in better properties and 10% replacement showed the maximum values of compressive and flexural strength as a result considered best percentage replacement in agreement with its noteworthy results.
Chemical compositions, CKD, compressive strength, flexural strength, reactivity
As tractors have played an important role in improving agricultural productivity, enhancing the efficiency of tractor has become of interest in recent years. In this study, a design of self-tuning fuzzy PID tracking control for a tractor is proposed. The steering control is performed on the front wheels, whereas the tractor is rear-wheel drive. Efficiency of the proposed self-tuning fuzzy PID controllers is compared to the results from the conventional PID controller testing at different trajectory scenarios under the specified accuracy of GPS and acceleration of the tractor. The experimental results show that the proposed self-tuning control exhibits better performance than the conventional PID technique in terms of the fast response of the steering wheels, and the small distance and heading angle errors.
This review is aimed to present an in-depth review of several methodologies on magnetic water treatment (MWT) that are employed as scale treatment in water pipeline and to critically discuss each method in order to determine the best outcome of MWT. The magnetically assisted water in pipeline in various applications are presented, argued and best variables are listed according to the performance of each MWT. The advantages and limitations of MWT are discussed and the main outcome from the review summarize the best method in MWT, especially in effectiveness of treating scale in terms of sustained environment benefits. Magnetic field application in water treatment has the potential to improve the water pipeline performance and lifetime. The application is also significant in controlling the growth of scale in upcoming system. Both of these benefits lead to healthier water treatment, increasing and maintaining the lifetime and performance of water system.
Magnetic water treatment, permanent magnet, pipe, scale, water
Kenaf fibre is a good reinforcement in fibre polymer composites due to its high strength and elastic modulus, high stiffness, low density, low cost and eco-efficient, less health hazards, renewability, good mechanical and thermal properties, and biodegradability. It is traditionally used for rope, twine, fish net and sacking materials. Recently, it was observed that kenaf fibre had huge potentials to replacing synthetic fibre in composites due to the rising environmental and ecological issues, thus this awareness has motivated efforts for the advancement of new innovative bio-based composites incorporating kenaf fibre for various end-use structural applications. This paper presents an overview of the development made so far in the area of kenaf fibre and its composites in terms of chemical and micro-structural properties, mechanical properties, dimensional stability, thermal stability, product development and application. Some fundamental issues and suggestions for further research in this area are also discussed.
Palm oil (PO) and fully hydrogenated palm oil (FHPO) were subjected to enzymatic interesterification using 9.5% of TLIM Lipozyme. The optimum condition for this process occurred at 62.75°C, with reaction time 172.50 minutes with the ratio of 1:1 for palm oil to hydrogenated palm oil respectively. The Palmitoyl-Oleoyl-Stereoyl (POS) yield obtained was approximately 15%. Product was subsequently subjected to a fractionation process at various cooling temperatures and reaction time. At 34°C, POS achieved was at the highest level which was approximately 31% after 12 hours cooling process. The study of physiochemical properties of the Cocoa butter Equivalent (CBE) fat was determined for the purpose of characterization identification. The properties identified were solid fat content, slip melting point (SMP) and iodine value (IV). The IV and SMP values obtained were 44.30 and 29°C respectively. However, CBE produced almost 0% of Solid Fat Content (SFC) at 30°C. Apart from the high yield of POS, the physicochemical characteristics showed significant compatibility with that of CB. In addition, the crystal polymorph of CBE 34 physicochemical characteristics of CBE34 (β'+β) was similar to CBE. Hence, from this study, CBE 34 is recommended for utilization in the confectionery industry as CBE.
Automation plays an important role in the manufacturing systems to increase the productivity with high flexibility in the production process. This may leads to the requirement of an information model to control the industrial machinery and processes. The information model contains the common product data. Hence, the data extraction is mandatory to extract the product data from the product model. This paper explains the extraction of product data through feature extraction process. A simplified system is developed to extract the data from the STEP file of a product model for subtractive features of prismatic parts. Using extracted data, the controller dependent NC codes were developed. The extracted data is also useful as reference data for checking the quality of manufactured parts by comparing with the data measured by coordinate measuring machine (CMM). In this paper, the integration concept is explained with the experiments conducted to produce the prismatic parts using the generated codes.
Doppler ultrasound is used in obstetrics and gynecology fields to serve as the complement mode in the standard prenatal scan. It aids in investigating fetus blood flow in expectant mothers' wombs, usually those who come with pregnancy complications. In the conventional ultrasound beam, the heat produced by attenuation is distributed over the area. However, the Doppler ultrasound beam is focused at only one point. This leads the heat to accumulate at that particular area and hence there is an increase in the temperature. Heat is considered as a teratogen in pregnancy, whereby an increase in the fetal temperature can be fatal to the fetus. Studies have found that Doppler mode is associated with higher acoustic output as compared to the conventional two-dimensional (2D) ultrasound mode. Several studies done on animals have ruled out the evidence of Doppler ultrasound bioeffects. This narrative review only discusses the thermally induced effect of ultrasound by using Doppler mode. This study reviews prior studies with keywords such as Doppler ultrasound, bioeffects, heating effects, rabbit, and pregnancy. Earlier studies noted that the risk of thermal effects increased with the increase of exposure time. However, Doppler ultrasound wave inducing fetal hyperthermia is not the main reason for causing adverse neonatal outcomes without taking into account other external factors. Therefore, it is essential for the practitioners to adopt and adapt the concept of 'as low as reasonably achievable' (ALARA) to avoid any subtle adverse effects.
In current scenario, treatment of any disease depends upon two major factors i.e. patient compliance and effective dosage regimen. The effective dose delivered by a dosage form to a patient depends on various parameters, which can be assessed by an effective and economic analytical method. In the present study a precise analytical method for estimating the combination of immunosuppressant drugs mycophenolate mofetil (MMF), tacrolimus (TAC) and prednisolone through RP-HPLC was developed. The mobile phase contained a mixture of acetonitrile and 0.35% triethylamine (pH 4.2) with orthophosphoric acid (70:30). As per ICH guidelines the optimized RP-HPLC method was validated with respect to linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision, repeatability, robustness, ruggedness. The accuracy of the method was determined in terms of % recovery of the standard. The obtained test results were compared with that of the standard drug. The results of the recovery study were found to be within the acceptance criteria (96.93- 103.99%), which indicated a good degree of sensitivity of the developed method in detection of analytes in a sample.
Papaya (Carica. Papaya L.) belongs to the Caricaceae family. They are grown in almost all tropical and subtropical regions in the world. In Brunei Darussalam, papaya is a non-seasonal fruit that is locally grown. It is also common to dry papaya. Drying is the process of removing water or moisture from a product with the benefit of improving shelf-life by impeding food spoilage by microorganisms. In this research, freshly ripened papaya was subjected to various drying methods and its effect on the vitamin C levels was investigated. The drying methods include sun drying (SD), oven drying (OD), freeze-drying (FD) and deep freezing (DF). Fresh samples were also investigated and acted as the control. The determination of vitamin C levels was carried out using an accredited Association of Official Agricultural Chemists (AOAC) indophenol titrimetric method. The result showed that FD samples had the highest vitamin C levels (5.84 ± 0.83 mg/100g) while SD has the least value of vitamin C (2.96 ± 0.47 mg/100g). In conclusion, the FD method resulted in highest vitamin C levels. Therefore, the FD method serves as the best industrial application with good vitamin C retention in papaya.
Deep freezing, freeze-drying, oven drying, papaya, sun drying, vitamin C
Hydraulic jumps on an inclined rectangular channel are the subject matter of this paper. The hydraulic jump is the sudden transition from a high velocity super critical flow to a subcritical flow regime in an open channel flow. The flow properties were solved using continuity and momentum principles. Laboratory experiments of hydraulic jumps in an inclined flume were conducted to verify the theoretical sequent-depth ratio, roller length and jump length. Measurements of velocities were made with an acoustic Doppler velocity meter for various Froude numbers flows. In the experiment, the bed slopes of 0.038, 0.094, 0.151, 0.210, 0.270, and 0.333 were used for measuring various flow parameters along the contour of the hydraulic jump. Results have shown that the sequent depth ratio increases with increasing the positive slope. Based on the present investigation the dimensionless length of the jump is significantly dependent on the bed.
Bed slope, energy loss, hydraulic jump, inclined rectangular flume, sequent depth ratio
The present work provides a new methodology for the flow measurement in a lined canal Huma tail distributary of Hirakud canal system, Odisha, India.The acoustic Doppler velocity meter was used for the direct measurement of velocity over full area and the length of canal. The entropy based Chiu's equation is used in the present work to find out a constant ratio between the average and the peak velocity of the channel. The location for maximum value is found from the velocity profile. Applying the constant ratio, the mean velocity can be obtained at various sections. With the measured cross sectional area and the mean velocity the discharge can be found. The maximum velocity is a technically important parameter always consists of a single value regardless of the flow conditions, and a cross-sectional shape. Thus the maximum velocity can be applied to estimate the mean velocity. In this work a formula based on the entropy concept has been used to find out the maximum velocity. The accuracy was verified using 13 sets measured with the help of ADV flow tracker. A comparison of the velocity estimated with the value actually measured showed very high accuracy.
Anaerobic composting is a promising method to fully transform food wastes into useful materials such as biofertilizer and biogas. In this study, the optimum proportions of food wastes containing vegetable, fruit and meat wastes with dry leaves or cow manure for composting were determined using the simplex centroid design and response optimizer. The effectiveness of the pilot-scale composting process was evaluated based on the targeted compost quality of C/N ratio at 21, pH value at 8 and electrical conductivity of 1 dS/m. Food wastes composting formulation with dry leaves suggested high percentage of dry leaves, 86.9% with low food wastes composition of 13.1% constituted by vegetable waste (1.1%), fruit waste (4.9%) and meat waste (7.1%). With cow manure formulation, only 6% of cow manure was recommended with another 94.0% of food wastes contributed by a fair mix of vegetable waste (23.2%), fruit waste (34.3%) and meat waste (36.5%). The developed regression models were experimentally validated with predicted responses obtained in acceptable ranges for C/N ratio (21.2 - 21.8), pH (7.92 - 7.99) and electrical conductivity (0.97 - 1.03 dS/m).
Rice (Oryza sativa L.) is one of the food crops, which is found to have the great capacity of cadmium (Cd) accumulation. This research was done to investigate the response to Cd accumulation in rice grown with different organic soil amendments (OA), namely soil supplemented with swine manure (SM), cow manure (CM), mixed chicken manure and rice husk (CR), vermicompost (VC), and greensward compost (GC), respectively. Each OA (4% w/w basis) was applied in each treatment with 3 Cd levels at 20, 40, and 60 mg/kg, respectively. The results showed that rice plants were not able to grow in 4% w/w of SM and CM, respectively and wither following 70 d of planting. It was found in the other treatment results that CR, VC, and GC increased harvest index (HI) as well as soil pH while decreasing soil Eh and Cd-HI, compared with the control treatment. All the Cd concentrations did not affect the height, but the wet weight of plants, decreased with increase in Cd concentrations. Regarding the Cd accumulation, it was found that CR is most effective in absorbing Cd in the paddy soils. In terms of Cd uptake, it was found that GC was the only OA that could reduce the Cd uptake in the rice plant parts. The result is consistent with reduction observed in the accumulation of cadmium in stems, leaves, and especially rice grain. Therefore, based on the current finding, both CR and GC soil amendments can be considered for immobilizing Cd in the contaminated fields.
Titanium (Ti) and Ti-based alloys presence the most widely applied as advanced biomaterials in biomedical implant applications. Moreover, these alloys are known to be the most valuable metallic materials including spinal cord surgical treatment. It becomes an interest due to its advantages compared to others, including its bio compatibility and corrosion resistant. However, an issue arises when it comes for permanent implant application as the alloy has a possible toxic effect produced from chemical reaction between body fluid environments with alloys chemical compositions. It also relies on the performance of neighbouring bone tissue to integrate with the implant surface. Abnormalities usually happen when surrounding tissue shows poor responses and rejection of implants that would leads to body inflammation. These cause an increase in foreign body reaction leading to severe body tissue response and thus, loosening of the implant. Corrosion effects and biocompatibility behaviour of implantation usage also become one of the reasons of implant damage. Here, this paper reviews the importance of using Ti and Ti-based alloys in biomedical implantation, especially in orthopaedic spinal cord injury. It also reviews the basic aspects of corrosion effects that lead to implant mechanical damage, poor response of body rejection and biocompatibility behaviour of implantation usage.
Bacterial infection, corrosion, mechanical damage, metal discolouration, metal hypersensitivity
In this study, the effects of addition of ammonium and aluminium-based hardeners into urea formaldehyde resin (UF) on the physico-mechanical properties and formaldehyde emission of the rubberwood particleboard were investigated. Four types of hardeners, namely ammonium chloride (AC), ammonium sulphate (AS), aluminium chloride (AlC) and aluminium sulphate (AlS), were added into UF resin. The acidity, gelation time, viscosity and free formaldehyde content of the UF/hardener mixtures were determined. Particleboard made with the UF/hardener mixtures were tested for physico-mechanical properties and formaldehyde emission. The pH values of the resin after addition of aluminium-based hardeners were higher and resulted in higher viscosity and shorter gelation time. Consequently, despite lower formaldehyde emission was recorded, the physico-mechanical properties of the resulted particleboard were inferior compared to that of ammonium-based hardeners. The best quality particleboard in terms of mechanical, physical and formaldehyde emission were obtained from the particleboard made with AS, followed by AC.
Carboxymethylcellulose (CMC) is a water-soluble polymer, which is widely used in various fields such as food additives, textiles, pharmaceuticals and cosmetics. In this study, hydrogel was prepared from CMC by using calcium chloride as a crosslinking agent. Optimization of the reaction was done through investigation of four different parameters which had different percentage of CMC (w/v), percentage of calcium chloride (w/v), reaction time and temperature. The gel content and swelling properties of the CMC hydrogel were studied. The highest gel content was 85.33% at 7% of CMC (w/v) with 2% of calcium chloride (w/v) in 24 hours reaction time at room temperature. The gel content increased with the increasing concentration of CMC and CaCl2. This was due to the higher number of functional groups of COO- that were available in more concentrated CMC which could crosslink with CaCl2 to give higher gel content. Increasing the percentage of CaCl2 will increase the electrostatic attraction between anionic charges of polymer chains and multivalent cation (Ca2+) that leads to increase in ionic crosslinking of CMC. The swelling properties of CMC hydrogel showed that the optimum degree of swelling was 45.33 (g/g). The swelling capacity of the hydrogel in water decreased with the increase of the gel content of CMC hydrogel. This could be due to the increase in the degree of crosslinking of the CMC hydrogel.
The continuous depletion of global oil reserves with the propensity for light distillates propels the oil and gas industry to explore heavier fractions of crude oils with significant amount of paraffin waxes. However, the precipitation and deposition of waxes during the transportation of these waxy crude oils in the pipelines contribute to several issues, such as the flowability reduction, excessive pumping cost, and wax gel formation, that adversely affect the supposedly steady offshore oil production. As a result, substantial resources are expended to resolve these flow assurance problems. The wax inhibitors and pour point depressants are developed and modified to meet the wax remediation criteria. Essentially, the wax crystals are formed through the nucleation, growth, and agglomeration processes, while the deposition of these waxes occurs via molecular diffusion and shear dispersion. The wax inhibitors are able to control the growth of wax crystals through nucleation, co-crystallization, adsorption, and dispersion interactions. This paper particularly assessed the following compounds: (1) polymeric wax inhibitors, (2) nano-hybrid pour point depressants, (3) organic solvents, and (4) surfactants. Given the significance of these compounds in the deposition and precipitation of waxes, it is imperative to comprehensively explore the types and nature of these compounds and their recent applications as well as to critically assess their strengths and drawbacks, which were addressed in this paper. Furthermore, the challenges of using these compounds and the factors that govern their efficiencies were also discussed. Accordingly, the carbon length and the molecular weight of both paraffin waxes and wax inhibitors are among the most influential factors.
Paraffin wax, pour point depressant, wax appearance temperature, wax inhibition, waxy crude oil
Support vector machine (SVM) is one of the most popular algorithms in machine learning and data mining. However, its reduced efficiency is usually observed for imbalanced datasets. To improve the performance of SVM for binary imbalanced datasets, a new scheme based on oversampling and the hybrid algorithm were introduced. Besides the use of a single kernel function, SVM was applied with multiple kernel learning (MKL). A weighted linear combination was defined based on the linear kernel function, radial basis function (RBF kernel), and sigmoid kernel function for MKL. By generating the synthetic samples in the minority class, searching the best choices of the SVM parameters and identifying the weights of MKL by minimizing the objective function, the improved performance of SVM was observed. To prove the strength of the proposed scheme, an experimental study, including noisy borderline and real imbalanced datasets was conducted. SVM was applied with linear kernel function, RBF kernel, sigmoid kernel function and MKL on all datasets. The performance of SVM with all kernel functions was evaluated by using sensitivity, G Mean, and F measure. A significantly improved performance of SVM with MKL was observed by applying the proposed scheme.