Abstract: Hybrid photovoltaic thermal (PV/T) solar system comprises a solar collector which is disposed on photovoltaic solar cells. The disadvantage of a conventional photovoltaic cell is that its performance decreases as the temperature increases. Indeed, part of the solar radiation is converted into electricity and is dissipated as heat, increasing the temperature of the photovoltaic cell with respect to the ambient temperature. The objective of this work is to study experimentally and implement a hybrid prototype to evaluate electrical and thermal performance. In this paper, an experimental study of two new configurations of hybrid collectors is exposed. The results are given and interpreted. The two configurations of absorber studied are a new combination with tubes and galvanized tank, the other is a tubes and sheet.
Abstract: At present, dictionary attack has been the basic tool for
recovering key passwords. In order to avoid dictionary attack, users
purposely choose another character strings as passwords. According to
statistics, about 14% of users choose keys on a keyboard (Kkey, for
short) as passwords. This paper develops a framework system to attack
the password chosen from Kkeys and analyzes its efficiency. Within
this system, we build up keyboard rules using the adjacent and parallel
relationship among Kkeys and then use these Kkey rules to generate
password databases by depth-first search method. According to the
experiment results, we find the key space of databases derived from
these Kkey rules that could be far smaller than the password databases
generated within brute-force attack, thus effectively narrowing down
the scope of attack research. Taking one general Kkey rule, the
combinations in all printable characters (94 types) with Kkey adjacent
and parallel relationship, as an example, the derived key space is about
240 smaller than those in brute-force attack. In addition, we
demonstrate the method's practicality and value by successfully
cracking the access password to UNIX and PC using the password
databases created
Abstract: In this paper, the shape design process is briefly discussed emphasizing the use of topology optimization in the conceptual design stage. The basic idea is to view feasible domains for sensitivity region concepts. In this method, the main process consists of two steps: as the design moves further inside the feasible domain using Taguchi method, and thus becoming more successful topology optimization, the sensitivity region becomes larger. In designing a double-eccentric butterfly valve, related to hydrodynamic performance and disc structure, are discussed where the use of topology optimization has proven to dramatically improve an existing design and significantly decrease the development time of a shape design. Computational Fluid Dynamics (CFD) analysis results demonstrate the validity of this approach.
Abstract: Severe acute respiratory syndrome (SARS) is a respiratory disease in humans which is caused by the SARS coronavirus. The treatment of coronavirus-associated SARS has been evolving and so far there is no consensus on an optimal regimen. The mainstream therapeutic interventions for SARS involve broad-spectrum antibiotics and supportive care, as well as antiviral agents and immunomodulatory therapy. The Protein- Ligand interaction plays a significant role in structural based drug designing. In the present work we have taken the receptor Angiotensin converting enzyme 2 and identified the drugs that are commonly used against SARS. They are Lopinavir, Ritonavir, Ribavirin, and Oseltamivir. The receptor Angiotensin converting enzyme 2 (ACE-2) was docked with above said drugs and the energy value obtained are as follows, Lopinavir (-292.3), Ritonavir (-325.6), Oseltamivir (- 229.1), Ribavirin (-208.8). Depending on the least energy value we have chosen the best two drugs out of the four conventional drugs. We tried to improve the binding efficiency and steric compatibility of the two drugs namely Ritonavir and Lopinavir. Several modifications were made to the probable functional groups (phenylic, ketonic groups in case of Ritonavir and carboxylic groups in case of Lopinavir respectively) which were interacting with the receptor molecule. Analogs were prepared by Marvin Sketch software and were docked using HEX docking software. Lopinavir analog 8 and Ritonavir analog 11 were detected with significant energy values and are probable lead molecule. It infers that some of the modified drugs are better than the original drugs. Further work can be carried out to improve the steric compatibility of the drug based upon the work done above for a more energy efficient binding of the drugs to the receptor.
Abstract: A new reverse phase-high performance liquid chromatography (RP-HPLC) method with fluorescent detector (FLD) was developed and optimized for Norfloxacin determination in human plasma. Mobile phase specifications, extraction method and excitation and emission wavelengths were varied for optimization. HPLC system contained a reverse phase C18 (5 μm, 4.6 mm×150 mm) column with FLD operated at excitation 330 nm and emission 440 nm. The optimized mobile phase consisted of 14% acetonitrile in buffer solution. The aqueous phase was prepared by mixing 2g of citric acid, 2g sodium acetate and 1 ml of triethylamine in 1 L of Milli-Q water was run at a flow rate of 1.2 mL/min. The standard curve was linear for the range tested (0.156–20 μg/mL) and the coefficient of determination was 0.9978. Aceclofenac sodium was used as internal standard. A detection limit of 0.078 μg/mL was achieved. Run time was set at 10 minutes because retention time of norfloxacin was 0.99 min. which shows the rapidness of this method of analysis. The present assay showed good accuracy, precision and sensitivity for Norfloxacin determination in human plasma with a new internal standard and can be applied pharmacokinetic evaluation of Norfloxacin tablets after oral administration in human.
Abstract: The development of wireless communication technologies has changed our living style in global level. After the international success of mobile telephony standards, the location and time independent voice connection has become a default method in daily telecommunications. As for today, highly advanced multimedia messaging plays a key role in value added service handling. Along with evolving data services, the need for more complex applications can be seen, including the mobile usage of broadcast technologies. Here performance of a system design for terrestrial multimedia content is examined with emphasis on mobile reception. This review paper has accommodated the understanding of physical layer role and the flavour of terrestrial channel effects on the terrestrial multimedia transmission using OFDM keeping DVB-H as benchmark standard.
Abstract: Textile structures are engineered and fabricated to
meet worldwide structural applications. Nevertheless, research
varying textile structure on natural fibre as composite reinforcement
was found to be very limited. Most of the research is focusing on
short fibre and random discontinuous orientation of the reinforcement
structure. Realizing that natural fibre (NF) composite had been
widely developed to be used as synthetic fibre composite
replacement, this research attempted to examine the influence of
woven and cross-ply laminated structure towards its mechanical
performances. Laminated natural fibre composites were developed
using hand lay-up and vacuum bagging technique. Impact and
flexural strength were investigated as a function of fibre type (coir
and kenaf) and reinforcement structure (imbalanced plain woven,
0°/90° cross-ply and +45°/-45° cross-ply). Multi-level full factorial
design of experiment (DOE) and analysis of variance (ANOVA) was
employed to impart data as to how fibre type and reinforcement
structure parameters affect the mechanical properties of the
composites. This systematic experimentation has led to determination
of significant factors that predominant influences the impact and
flexural properties of the textile composites. It was proven that both
fibre type and reinforcement structure demonstrated significant
difference results. Overall results indicated that coir composite and
woven structure exhibited better impact and flexural strength. Yet,
cross-ply composite structure demonstrated better fracture resistance.
Abstract: Fine alignment of main ship power plants mechanisms
and shaft lines provides long-term and failure-free performance of
propulsion system while fast and high-quality installation of
mechanisms and shaft lines decreases common labor intensity. For
checking shaft line allowed stress and setting its alignment it is
required to perform calculations considering various stages of life
cycle. In 2012 JSC SSTC developed special software complex
“Shaftline” for calculation of alignment of having its own I/O
interface and display of shaft line 3D model. Alignment of shaft line
as per bearing loads is rather labor-intensive procedure. In order to
decrease its duration, JSC SSTC developed automated alignment
system from ship power plants mechanisms. System operation
principle is based on automatic simulation of design load on bearings.
Initial data for shaft line alignment can be exported to automated
alignment system from PC “Shaft line”.
Abstract: This article demonstrated development of
controlled release system of an NSAID drug, Diclofenac
sodium employing different ratios of Ethyl cellulose.
Diclofenac sodium and ethyl cellulose in different proportions
were processed by microencapsulation based on phase
separation technique to formulate microcapsules. The
prepared microcapsules were then compressed into tablets to
obtain controlled release oral formulations. In-vitro evaluation
was performed by dissolution test of each preparation was
conducted in 900 ml of phosphate buffer solution of pH 7.2
maintained at 37 ± 0.5 °C and stirred at 50 rpm. At predetermined
time intervals (0, 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 10, 12,
16, 20 and 24 hrs). The drug concentration in the collected
samples was determined by UV spectrophotometer at 276 nm.
The physical characteristics of diclofenac sodium
microcapsules were according to accepted range. These were
off-white, free flowing and spherical in shape. The release
profile of diclofenac sodium from microcapsules was found to
be directly proportional to the proportion of ethylcellulose and
coat thickness. The in-vitro release pattern showed that with
ratio of 1:1 and 1:2 (drug: polymer), the percentage release of
drug at first hour was 16.91 and 11.52 %, respectively as
compared to 1:3 which is only 6.87 % with in this time. The
release mechanism followed higuchi model for its release
pattern. Tablet Formulation (F2) of present study was found
comparable in release profile the marketed brand Phlogin-SR,
microcapsules showed an extended release beyond 24 h.
Further, a good correlation was found between drug release
and proportion of ethylcellulose in the microcapsules.
Microencapsulation based on coacervation found as good
technique to control release of diclofenac sodium for making
the controlled release formulations.
Abstract: Two geometrically nonlinear plate theories, based either on first- or third-order transverse shear deformation theory are used for finite element modeling and simulation of the transient response of smart structures incorporating piezoelectric layers. In particular the time histories of nonlinear vibrations and sensor voltage output of a thin beam with a piezoelectric patch bonded to the surface due to an applied step force are studied.
Abstract: A homologous series of aromatic esters, 4-nalkanoyloxybenzylidene-
4--bromoanilines, nABBA,
consisting of two 1,4-disubstituted phenyl cores and a Schiff
base central linkage was synthesized. All the members can be
differed by the number of carbon atoms at terminal
alkanoyloxy chain (CnH2n-1COO-, n = 2, 6, 18). The molecular
structure of nABBA was confirmed with infrared
spectroscopy, nuclear magnetic resonance (NMR)
spectroscopy and electron-ionization mass (EI-MS)
spectrometry. Mesomorphic properties were studied using
differential scanning calorimetry and polarizing optical
microscopy.
Abstract: one of the significant factors for improving the
accuracy of Land Surface Temperature (LST) retrieval is the correct
understanding of the directional anisotropy for thermal radiance. In
this paper, the multiple scattering effect between heterogeneous
non-isothermal surfaces is described rigorously according to the
concept of configuration factor, based on which a directional thermal
radiance model is built, and the directional radiant character for urban
canopy is analyzed. The model is applied to a simple urban canopy
with row structure to simulate the change of Directional Brightness
Temperature (DBT). The results show that the DBT is aggrandized
because of the multiple scattering effects, whereas the change range of
DBT is smoothed. The temperature difference, spatial distribution,
emissivity of the components can all lead to the change of DBT. The
“hot spot" phenomenon occurs when the proportion of high
temperature component in the vision field came to a head. On the other
hand, the “cool spot" phenomena occur when low temperature
proportion came to the head. The “spot" effect disappears only when
the proportion of every component keeps invariability. The model
built in this paper can be used for the study of directional effect on
emissivity, the LST retrieval over urban areas and the adjacency effect
of thermal remote sensing pixels.
Abstract: Three-dimensional geometric models have been used
to present architectural and engineering works, showing their final
configuration. When the clarification of a detail or the constitution of
a construction step in needed, these models are not appropriate. They
do not allow the observation of the construction progress of a
building. Models that could present dynamically changes of the
building geometry are a good support to the elaboration of projects.
Techniques of geometric modeling and virtual reality were used to
obtain models that could visually simulate the construction activity.
The applications explain the construction work of a cavity wall and a
bridge. These models allow the visualization of the physical
progression of the work following a planned construction sequence,
the observation of details of the form of every component of the
works and support the study of the type and method of operation of
the equipment applied in the construction. These models presented
distinct advantage as educational aids in first-degree courses in Civil
Engineering. The use of Virtual Reality techniques in the
development of educational applications brings new perspectives to
the teaching of subjects related to the field of civil construction.
Abstract: The Romanian government has been making
significant attempts to make its services and information available on
the Internet. According to the UN e-government survey conducted in
2008, Romania comes under mid range countries by utilization of egovernment
(percent of utilization 41%). Romania-s national portal
www.e-guvernare.ro aims at progressively making all services and
information accessible through the portal. However, the success of
these efforts depends, to a great extent, on how well the targeted
users for such services, citizens in general, make use of them. For
this reason, the purpose of the presented study was to identify what
factors could affect the citizens' adoption of e-government services.
The study is an extension of the Technology Acceptance Model. The
proposed model was validated using data collected from 481 citizens.
The results provided substantial support for all proposed hypotheses
and showed the significance of the extended constructs.
Abstract: An overview of the important aspects of managing
and controlling industrial effluent discharges to public sewers namely
sampling, characterization, quantification and legislative controls has
been presented. The findings have been validated by means of a case
study covering three industrial sectors namely, tanning, textile
finishing and food processing industries. Industrial effluents
discharges were found to be best monitored by systematic and
automatic sampling and quantified using water meter readings
corrected for evaporative and consumptive losses. Based on the
treatment processes employed in the public owned treatment works
and the chemical oxygen demand and biochemical oxygen demand
levels obtained, the effluent from all the three industrial sectors
studied were found to lie in the toxic zone. Thus, physico-chemical
treatment of these effluents is required to bring them into the
biodegradable zone. KL values (quoted to base e) were greater than
0.50 day-1 compared to 0.39 day-1 for typical municipality
wastewater.
Abstract: In this paper we will develop a sequential life test approach applied to a modified low alloy-high strength steel part used in highway overpasses in Brazil.We will consider two possible underlying sampling distributions: the Normal and theInverse Weibull models. The minimum life will be considered equal to zero. We will use the two underlying models to analyze a fatigue life test situation, comparing the results obtained from both.Since a major chemical component of this low alloy-high strength steel part has been changed, there is little information available about the possible values that the parameters of the corresponding Normal and Inverse Weibull underlying sampling distributions could have. To estimate the shape and the scale parameters of these two sampling models we will use a maximum likelihood approach for censored failure data. We will also develop a truncation mechanism for the Inverse Weibull and Normal models. We will provide rules to truncate a sequential life testing situation making one of the two possible decisions at the moment of truncation; that is, accept or reject the null hypothesis H0. An example will develop the proposed truncated sequential life testing approach for the Inverse Weibull and Normal models.
Abstract: Deoxyribonucleic Acid or DNA computing has
emerged as an interdisciplinary field that draws together chemistry,
molecular biology, computer science and mathematics. Thus, in this
paper, the possibility of DNA-based computing to solve an absolute
1-center problem by molecular manipulations is presented. This is
truly the first attempt to solve such a problem by DNA-based
computing approach. Since, part of the procedures involve with
shortest path computation, research works on DNA computing for
shortest path Traveling Salesman Problem, in short, TSP are reviewed.
These approaches are studied and only the appropriate one is adapted
in designing the computation procedures. This DNA-based
computation is designed in such a way that every path is encoded by
oligonucleotides and the path-s length is directly proportional to the
length of oligonucleotides. Using these properties, gel electrophoresis
is performed in order to separate the respective DNA molecules
according to their length. One expectation arise from this paper is that
it is possible to verify the instance absolute 1-center problem using
DNA computing by laboratory experiments.
Abstract: The Internet and the ever growing applications enable
communities to share and collaborate through common platforms.
However, this growing pattern is not witnessed yet even for elearning.
This paper is based on a doctoral research which aimed at
researching the ways students interact in an online campus and the
supports that they look for and require. Content analysis, based on the
Panchoo/Jaillet methodology, was done on four synchronous
meetings between a tutor and his ten students. The UNIV-Rct ecampus,
analogical to a physical campus, was found to be user
friendly and the students enrolled in a master-s course faced no
difficulties in using it. In addition to the environmental aspects, the
pedagogical implementation of the course has driven the students to
interact and collaborate significantly and this has contributed to
overcome the problems faced by the distance learners. This
completely online model was found to be fruitful in helping distant
learners fight their loneliness and brave their difficulties in a socioconstructivism
approach.
Abstract: A robust control approach is proposed for a high speed manipulator using a hybrid computed torque control approach in the state space. The high-speed manipulator is driven by permanent magnet dc motors to track a trajectory in the joint space in the presence of disturbances. Tracking problem is analyzed in the state space where the completed models are considered for actuators. The proposed control approach can guarantee the stability and a satisfactory tracking performance. A two-link elbow manipulator driven by electrical actuators is simulated and results are shown to satisfy conditions under technical specifications.
Abstract: This paper describes the development of a fully
automated measurement software for antenna radiation pattern
measurements in a Compact Antenna Test Range (CATR). The
CATR has a frequency range from 2-40 GHz and the measurement
hardware includes a Network Analyzer for transmitting and
Receiving the microwave signal and a Positioner controller to control
the motion of the Styrofoam column. The measurement process
includes Calibration of CATR with a Standard Gain Horn (SGH)
antenna followed by Gain versus angle measurement of the Antenna
under test (AUT). The software is designed to control a variety of
microwave transmitter / receiver and two axis Positioner controllers
through the standard General Purpose interface bus (GPIB) interface.
Addition of new Network Analyzers is supported through a slight
modification of hardware control module. Time-domain gating is
implemented to remove the unwanted signals and get the isolated
response of AUT. The gated response of the AUT is compared with
the calibration data in the frequency domain to obtain the desired
results. The data acquisition and processing is implemented in
Agilent VEE and Matlab. A variety of experimental measurements
with SGH antennas were performed to validate the accuracy of
software. A comparison of results with existing commercial
softwares is presented and the measured results are found to be
within .2 dBm.