We consider a vector nonlinear differential equation of fourth order with a constant delay. We establish new sufficient conditions, which guarantee the instability of the zero solution of that equation. An example is given to illustrate the theoretical analysis made in this paper
The discretization of the second-order linear self-adjoint ellliptic partial differential equation problem subject to periodic boundary conditions results in a system of linear equations of the form Mu = s, where M is a block cyclic tridiagonal square matric. In this paper, the relationship between the spectral radius and overrelaxation factor for the problem is derived.
Pendiskretan masalah persamaan pembeza separa (PPS) eliptik swadampingan linear peringkat kedua menghasilkan satu sistem persamaan linear bentuk Mu = s, dengan M merupakan satu matriks segiempatsama tiga pepenjuru berkitar blok. Dalam kertas ini, hubungan di antara jejari spektrum dan faktor pengenduran berlebihan untuk masalah itu akan dirumuskan.
A high-order uniform Cartesian grid compact finite difference scheme for the Goursat problem is developed. The basic idea of high-order compact schemes is to find the compact approximations to the derivatives terms by differentiating centrally the governing equations. Our compact scheme will approximate the derivative terms by involving the higher terms and reducing the number of grid points. The compact finite difference scheme is given for general form of the Goursat problem in uniform domain and illustrates the performance by applying a linear problem. Numerical experiments have been conducted with the new scheme and encouraging results have been obtained. In this paper we present the compact finite difference scheme for the Goursat problem. With the aid of computational software the scheme was programmed for determining the relative errors of linear Goursat problem.
The development of economy is closely related with the inflation rate of the country. Generally the inflation can be measured by the Consumer Price Index (CPl). The aim of this paper is using overlapping measure and cumulative measure to measure the inflation. In overall, these two methods are adequate for measuring the inflation. As a result, monthly measure is useful because it believe can give a perfect measure (since its sample is large) and can get rid of or smaller the error. Besides that, the value of the weighted CPl and the unweighted CPl are almost same. As the result, the unweighted of CPl is used to measure the inflation. The result of this two methods are satisfactory.
[Perkembangan sesuatu ekonomi adalah berkait rapat dengan kadar inflasi dalam sesebuah negara. Secara amnya, inflasi dapat diukur dengan Indeks Harga Pengguna (IHP). Tujuan kertas kerja ini adalah mengukur inflasi dengan menggunakan kaedah data bertindih dan kaedah kumulatif. Pada keseluruhannya kedua-dua kaedah tersebut adalah sesuai digunakan sebagai pengukuran inflasi. Oleh hal yang demikian, pengukuran secara bulanan digunakan kerana dipercayai bahawa ia dapat memberi ukuran yang lebih tepat (saiz sampel yang besar) dan dapat mengelakkan atau mengecilkan ralat berlaku. Selain itu, penggunaan IHP berpemberat dan IHP tanpa pemberat didapati mempunyai nilai yang hampir sama. Oleh itu, nilai IHP tanpa pemberat digunakan dalam pengukuran inflasi. Keputusan yang didapati daripada kedua-dua kaedah tersebut adalah memuaskan]
Quality of bond between layers of asphaltic concrete course is a key element to ensure the performance of a modern asphalt pavement. A proper interlayer bond ensures the structural integrity of the pavement and prevents possible distresses from occurring within the designed service life. In Malaysia, delamination is a common distress related to insufficient degree of adhesion though slippage failure can be occasionally encountered. Generally, bond development is closely related to the design factors and construction factors. This paper however focused on the construction factors only, hoping to provide some useful information which might be overlooked by the contractors during construction but is of extreme important especially in enhancing the bond development in the asphalt layers. The construction factors in particular interest discussed in this paper include curing time of asphalt emulsion, surface condition of a pavement and technology and quality of workmanship and construction. It is important to note that both design factors and construction factors are inter-related in optimizing the degree of adhesion. Thus, all factors need to be carefully identified and fulfilled in order to maximize the bond strength between pavement surfacing layers for a better quality and longer service life of pavement in Malaysia.
The transformation method (TM) of fuzzy arithmetic is aimed at simulation and analysis of a system. The aim of this paper is to use fuzzy arithmetic based on the TM on a state space of a steam turbine system. The model is then used to identify the degree of influence of each parameter on the system. Simulation and analysis of the system are presented in this paper.
Although a significant amount of brewery wastewater (BW) is generated during beer production, the nutrients in the BW could be reused as a potential bio-resource for biohydrogen production. Therefore, improvements in photofermentative biohydrogen production due to a combination of BW and pulp and paper mill effluent (PPME) as a mixed production medium were investigated comprehensively in this study. The experimental results showed that both the biohydrogen yield and the chemical oxygen demand removal were improved through the combination of BW and PPME. The best biohydrogen yield of 0.69 mol H2/L medium was obtained using the combination of 10 % BW + 90 % PPME (10B90P), while the reuse of the wastewater alone (100 % BW and 100 % PPME) resulted in 42.3 and 44.0 % less biohydrogen yields than the highest yield, respectively. The greatest light efficiency was 1.97 % and was also achieved using the combination of both wastewaters at 10B90P. This study revealed the potential of reusing and combining two different effluents together, in which the combination of BW and PPME improved the nutrients and light penetration into the mixed production medium.
Clinicians, working in the health-care diagnostic systems of developing countries, currently face the challenges of rising costs, increased number of patient visits, and limited resources. A significant trend is using low-cost substrates to develop microfluidic devices for diagnostic purposes. Various fabrication techniques, materials, and detection methods have been explored to develop these devices. Microfluidic paper-based analytical devices (μPADs) have gained attention for sensing multiplex analytes, confirming diagnostic test results, rapid sample analysis, and reducing the volume of samples and analytical reagents. μPADs, which can provide accurate and reliable direct measurement without sample pretreatment, can reduce patient medical burden and yield rapid test results, aiding physicians in choosing appropriate treatment. The objectives of this review are to provide an overview of the strategies used for developing paper-based sensors with enhanced analytical performances and to discuss the current challenges, limitations, advantages, disadvantages, and future prospects of paper-based microfluidic platforms in clinical diagnostics. μPADs, with validated and justified analytical performances, can potentially improve the quality of life by providing inexpensive, rapid, portable, biodegradable, and reliable diagnostics.
The study reports on the preparation of cellulose nanocrystals (CNCs) from wastepaper, as an environmental friendly approach of source material, which can be a high availability and low-cost precursor for cellulose nanomaterial processing. Alkali and bleaching treatments were employed for the extraction of cellulose particles followed by controlled-conditions of acid hydrolysis for the isolation of CNCs. Attenuated total reflectance Fourier Transform Infrared (ATR FTIR) spectroscopy was used to analyze the cellulose particles extracted while Transmission electron microscopy images confirmed the presence of CNCs. The diameters of CNCs are in the range of 3-10nm with a length of 100-300nm while a crystallinity index of 75.9% was determined from X-ray diffraction analysis. The synthesis of this high aspect ratio of CNCs paves the way toward alternative reuse of wastepaper in the production of CNCs.
Recovery of cellulose fibres from paper mill effluent has been studied using common polysaccharides or biopolymers such as Guar gum, Xanthan gum and Locust bean gum as flocculent. Guar gum is commonly used in sizing paper and routinely used in paper making. The results have been compared with the performance of alum, which is a common coagulant and a key ingredient of the paper industry. Guar gum recovered about 3.86mg/L of fibre and was most effective among the biopolymers. Settling velocity distribution curves demonstrated that Guar gum was able to settle the fibres faster than the other biopolymers; however, alum displayed the highest particle removal rate than all the biopolymers at any of the settling velocities. Alum, Guar gum, Xanthan gum and Locust bean gum removed 97.46%, 94.68%, 92.39% and 92.46% turbidity of raw effluent at a settling velocity of 0.5cm/min, respectively. The conditions for obtaining the lowest sludge volume index such as pH, dose and mixing speed were optimised for guar gum which was the most effective among the biopolymers. Response surface methodology was used to design all experiments, and an optimum operational setting was proposed. The test results indicate similar performance of alum and Guar gum in terms of floc settling velocities and sludge volume index. Since Guar gum is a plant derived natural substance, it is environmentally benign and offers a green treatment option to the paper mills for pulp recycling.
This paper utilizes the background oriented schlieren (BOS) technique to measure the velocity field of a variable density round jet. The density field of the jet is computed based on the light deflection created during the passage of light through the understudy jet. The deflection vector estimation was carried out using phase-based optical flow algorithms. The density field is further exploited to extract the axial and radial velocity vectors with the aid of continuity and energy equations. The experiment is conducted at six different jet-exit temperature values. Additional turbulence parameters, such as velocity variance and power spectral density of the vector field, are also computed. Finally, the measured velocity parameters are compared with the hot wire anemometer measurements and their correlation is displayed.
Good Clinical Practice (GCP) is an international ethical and scientific quality standard for the design, conduct, performance, monitoring, auditing, recording, analyses and reporting of clinical trials. It also serves to protect the rights, integrity and confidentiality of trial subjects. It is very important to understand the background of the formation of the ICH-GCP guidelines as this, in itself, explains the reasons and the need for doing so. In this paper, we address the historical background and the events that led up to the formation of these guidelines. Today, the ICH-GCP guidelines are used in clinical trials throughout the globe with the main aim of protecting and preserving human rights.
This work presents some comments concerning the paper entitled 'Lattice Boltzmann simulation of alumina-water nanofluid in a square cavity' by Yurong He, Cong Qi, Yanwei Hu, Bin Qin, Fengchen Li and Yulong Ding which was published in Nanoscale Research Letters in 2011. The comments are related to the numerical parameters and the computed results of average Nusselt number.
Numerous applications of artificial olfaction resulting from research in many branches of sciences have caused considerable interest in the enhancement of these systems. In this paper, we offer an architecture which is suitable for critical applications, such as medical diagnosis, where reliability and precision are deemed important. The proposed architecture is able to tolerate failures in the sensors of the array. In this study, the discriminating ability of the proposed architecture in detecting complex odors, as well as the performance of the proposed architecture in encountering sensor failure, were investigated and compared with the generic architecture. The results demonstrated that by applying the proposed architecture in the artificial olfactory system, the performance of system in the healthy mode was identical to the classic structure. However, in the faulty situation, the proposed architecture implied high identification ability of odor samples, while the generic architecture showed very poor performance in the same situation. Based on the results, it was possible to achieve high odor identification through the developed artificial olfactory system using the proposed architecture.
Technoeconomic paradigms based economic growth theories suggest that waves of technological innovations drove the economic growth of advanced economies. Widespread economic degradation and pollution is an unintended consequence of such growth. Tackling environmental and social issues at firm levels would help us to overcome such issues at macro-levels. Consequently, the Triple Bottom Line (TBL) reporting approach promotes firm level economic, environmental and social performances. Incorporating Zink's (2014) 3-pillar presentation model, this paper indicates that economic, social and environmental performances tend to be reported at firm level. All three pillars are not covered evenly at the activity levels. Thus, a loophole is identified whereby excellent environmental performance at activity levels could potentially leave poor social performance undisclosed. A refinement of the TBL paradigm, whereby all three pillars are covered at the activity level, is suggested, to enhance sustainability reporting.
This procedure is easy to use and is cost-effective because it uses equipment that exist in any office or institution. The material used, transparency film for use with plain paper copier, is less expensive than either photographic slide film or normal slide films. Moreover, the transparency sheet can be used again for photocopying until the sheet is fully used up. There is no added cost of development of film, or is it necessary to wait for the whole roll of film to be used before the label can be retrieved and used. The background of the label is clear and only the black images of the characters of the label can be clearly seen. The effect of the transparency film, photocopy ink, and adhesive glue is not known. But no adverse effects have been noted. Microlabels have advantages over conventional labels with characters in font size 8 to 12, because more information, such as the full name of the patient, sex, country of origin, and national identification number can be incorporated. With more detailed information, quick identification of a deceased person can be made. Microlabels with a clear background will have minimal esthetic impact on the patient. The disadvantages of the technique is that it may not withstand a fire. In situations where the deceased body is badly burned, the denture and its identification strip may be burned, too. However, this risk can be minimized by placing the strip in the most posterior part of the denture-palatal in the maxillary denture and distal lingual in the mandibular denture. For testing of durability, dentures with the labels were placed in water for up to 4 months. The labels showed no sign of fading or deterioration.
In this paper, Taguchi experimental design technique was applied for optimization of chromium (Cr)/silver (Ag)/indium
tin oxide (ITO) SPR sensor for operation in near infrared region. Four factors were considered which include wavelength,
thickness of Cr, thickness of Ag, and thickness of ITO. Finite-difference-time-domain (FDTD) method was used in numerical
analysis for minimum reflectance (Rmin) and full-width-at-half-maximum (FWHM) performance parameters. The results
obtained from the Taguchi method shows that the optimized parameter for Rmin was 785 nm of wavelength, Cr (1 nm),
Ag (40 nm) and ITO (20 nm), whereas the optimized parameter for FWHM was 785 of wavelength, Cr (0 nm), Ag (40 nm)
and ITO (0 nm). In short, the optimum parameters for achieving the desired performance of sensor were successfully
predicted using Taguchi optimization method.
This paper is about the reduction of the overall size of metal blanking sheet that is being used to form a stamping product or car body panel of a car manufacturer in Malaysia. The current blanking sheet produces extra waste which will be recycled and does not contribute to increase productivity but increases inventory cost. The reduction in the blanking sheet size will lead to the reduction of raw material hence reduced the production cost. However, the reduced size of blanking sheet could affect the yield strength of the product. The study of the yield strength and yield improvement of the product are done by simulating stress analysis by using CATIA software. The results show that the new proposed size of the metal blanking sheet provides accuracy of the product dimension as well as maintaining the yield strength of the product and it reduced a significant amount of metal scrap which is nearly 4% of material weight and save around 10% of inventory cost.
Algae biomass comprises variety of biochemicals components such as carbohydrates, lipids and protein, which make them a feasible feedstock for biofuel production. However, high production cost mainly due to algae cultivation remains the main challenge in commercializing algae biofuels. Hence, extraction of other high value-added bioproducts from algae biomass is necessary to enhance the economic feasibility of algae biofuel production. This paper is aims to deliberate the recent developments of conventional technologies for algae biofuels production, such as biochemical and chemical conversion pathways, and extraction of a variety of bioproducts from algae biomass for various potential applications. Besides, life cycle evaluation studies on microalgae biorefinery are presented, focusing on case studies for various cultivation techniques, culture medium, harvesting, and dewatering techniques along with biofuel and bioenergy production pathways. Overall, the algae biorefinery provides new opportunities for valorisation of algae biomass for multiple products synthesis.