Abstract: This paper presents a new ultra-wideband (UWB) bandpass filter (BPF) with sharp roll-off and dual-notched bands. The filter consists of a triangle ring multi-mode resonator (MMR) with the stub-loaded resonator (SLR) for controlling the two transmission zeros at 2.8 / 11 GHz, the embedded open-circuited stub and the asymmetric tight coupled input/output (I/O) lines for introducing the dual notched bands at 5.2 / 6.8 GHz. The attenuation slope in the lower and higher passband edges of the proposed filter show 160- and 153-dB/GHz, respectively. This study mainly provides a simple method to design a UWB bandpass filter with high passband selectivity and dual-notched bands for satisfying the Federal Communications Commission (FCC-defined) indoor UWB specification
Abstract: In this article, a high vacuum system for the evaporation of organic semiconductors is introduced and a mathematical model is given. Based on the exact input output linearization a deposition rate controller is designed and tested with different evaporation materials.
Abstract: Theory of Constraints has been emerging as an
important tool for optimization of manufacturing/service systems.
Goldratt in his first book “ The Goal " gave the introduction on
Theory of Constraints and its applications in a factory scenario. A
large number of production managers around the globe read this book
but only a few could implement it in their plants because the book did
not explain the steps to implement TOC in the factory. To overcome
these limitations, Goldratt wrote this book to explain TOC, DBR and
the method to implement it. In this paper, an attempt has been made
to summarize the salient features of TOC and DBR listed in the book
and the correct approach to implement TOC in a factory setting. The
simulator available along with the book was actually used by the
authors and the claim of Goldratt regarding the use of DBR and
Buffer management to ease the work of production managers was
tested and was found to be correct.
Abstract: In recent years application of natural antimicrobials
instead of conventional ones, due to their hazardous effects on health,
has got serious attentions. On the basis of the results of different
studies, chitosan, a natural bio-degradable and non-toxic
biopolysaccharide derived from chitin, has potential to be used as a
natural antimicrobial. Chitosan has exhibited high antimicrobial
activity against a wide variety of pathogenic and spoilage
microorganisms, including fungi, and Gram-positive and Gramnegative
bacteria. The antimicrobial action is influenced by intrinsic
factors such as the type of chitosan, the degree of chitosan
polymerization and extrinsic factors such as the microbial organism,
the environmental conditions and presence of the other components.
The use of chitosan in food systems should be based on sufficient
knowledge of the complex mechanisms of its antimicrobial mode of
action. In this article we review a number of studies on the
investigation of chitosan antimicrobial properties and application of
them in culture and food mediums.
Abstract: In this paper, a novel system
recognition of human faces without using face
different color photographs is proposed. It mainly in
face detection, normalization and recognition. Foot
method of combination of Haar-like face determined
segmentation and region-based histogram stretchi
(RHST) is proposed to achieve more accurate perf
using Haar. Apart from an effective angle norm
side-face (pose) normalization, which is almost a might be important and beneficial for the prepr
introduced. Then histogram-based and photom
normalization methods are investigated and ada
retinex (ASR) is selected for its satisfactory illumin
Finally, weighted multi-block local binary pattern
with 3 distance measures is applied for pair-mat
Experimental results show its advantageous perfo
with PCA and multi-block LBP, based on a principle.
Abstract: Continuously growing needs for Internet applications
that transmit massive amount of data have led to the emergence of
high speed network. Data transfer must take place without any
congestion and hence feedback parameters must be transferred from
the receiver end to the sender end so as to restrict the sending rate in
order to avoid congestion. Even though TCP tries to avoid
congestion by restricting the sending rate and window size, it never
announces the sender about the capacity of the data to be sent and
also it reduces the window size by half at the time of congestion
therefore resulting in the decrease of throughput, low utilization of
the bandwidth and maximum delay. In this paper, XCP protocol is
used and feedback parameters are calculated based on arrival rate,
service rate, traffic rate and queue size and hence the receiver
informs the sender about the throughput, capacity of the data to be
sent and window size adjustment, resulting in no drastic decrease in
window size, better increase in sending rate because of which there is
a continuous flow of data without congestion. Therefore as a result of
this, there is a maximum increase in throughput, high utilization of
the bandwidth and minimum delay. The result of the proposed work
is presented as a graph based on throughput, delay and window size.
Thus in this paper, XCP protocol is well illustrated and the various
parameters are thoroughly analyzed and adequately presented.
Abstract: Current mode circuits like current conveyors are
getting significant attention in current analog ICs design due to their
higher band-width, greater linearity, larger dynamic range, simpler
circuitry, lower power consumption and less chip area. The second
generation current controlled conveyor (CCCII) has the advantage of
electronic adjustability over the CCII i.e. in CCCII; adjustment of the
X-terminal intrinsic resistance via a bias current is possible. The
presented approach is based on the CMOS implementation of second
generation positive (CCCII+), negative (CCCII-) and dual Output
Current Controlled Conveyor (DOCCCII) and its application as
Universal filter. All the circuits have been designed and simulated
using 65nm CMOS technology model parameters on Cadence
Virtuoso / Spectre using 1V supply voltage. Various simulations have
been carried out to verify the linearity between output and input
ports, range of operation frequency, etc. The outcomes show good
agreement between expected and experimental results.
Abstract: Genetic Algorithms (GAs) are direct searching
methods which require little information from design space. This
characteristic beside robustness of these algorithms makes them to be
very popular in recent decades. On the other hand, while this method
is employed, there is no guarantee to achieve optimum results. This
obliged designer to run such algorithms more than one time to
achieve more reliable results. There are many attempts to modify the
algorithms to make them more efficient. In this paper, by application
of fractal dimension (particularly, Box Counting Method), the
complexity of design space are established for determination of
mutation and crossover probabilities (Pm and Pc). This methodology
is followed by a numerical example for more clarification. It is
concluded that this modification will improve efficiency of GAs and
make them to bring about more reliable results especially for design
space with higher fractal dimensions.
Abstract: Plastics occupy wide place in the applications of
automotive, electronics and house goods. Especially reinforced
plastics become popular because of their high strength besides their
advantages of low weight and easy manufacturability. In this study,
mechanical and morphological properties of polypropylene (PP) and
high density polyethylene (HDPE) matrix composites reinforced with
surface modified nano titan dioxide (TiO2) particles were
investigated. Surface modification was made by coating the nano
powders with maleic anhydride grafted styrene ethylene butylene
styrene (SEBS-g-MA) and silane, respectively. After surface
modification, PP/TiO2 and HDPE/TiO2 composites were obtained by
using twin screw extruder at titan dioxide loading of 1 wt.%, 3 wt.%
and 5 wt.%. Effects of surface modification were determined by
thermal and morphological analysis. SEBS-g-MA provided bridging
effect between TiO2 particles and polymer matrix while silane was
effective as a dispersant. Depending on that, homogenous structures
without agglomeration were obtained. Mechanical tests were
performed on the injection moldings of the composites for obtaining
the impact strength, tensile strength, stress at break, elongation and
elastic modulus. Reinforced HDPE and PP moldings gave higher
tensile strength and elastic modulus due to the rigid structure of TiO2.
Slight increment was seen in stress at break. Elongation and impact
strength decreased due to the stiffness of the nano titan dioxide.
Abstract: Commercial infrastructures intended for use as leisure
retreats such as golf and ski resorts have been extensively developed in many rural areas of Japan. However, following the burst of the economic bubble in the 1990s, several existing resorts faced tough
management decisions and some were forced to close their business.
In this study, six alternative management options for restructuring the
existing golf courses (park, cemetery, biofuel production, reforestation,
pasturing and abandonment) are examined and their environmental
and economic impacts are quantitatively assessed. In addition,
restructuring scenarios of these options and an ex-ante assessment
model are developed. The scenario analysis by Monte Carlo simulation shows a clear trade-off between GHG savings and benefit/cost (B/C) ratios, of which “Restoring Nature" scenario
absorbs the most CO2 among the four scenarios considered, but its B/C
ratio is the lowest. This study can be used to select or examine options
and scenarios of golf course management and rural environmental
management policies.
Abstract: A linear feedback shift register (LFSR) is proposed which targets to reduce the power consumption from within. It reduces the power consumption during testing of a Circuit Under Test (CUT) at two stages. At first stage,
Control Logic (CL) makes the clocks of the switching units
of the register inactive for a time period when output from
them is going to be same as previous one and thus reducing
unnecessary switching of the flip-flops. And at second stage,
the LFSR reorders the test vectors by interchanging the bit
with its next and closest neighbor bit. It keeps fault coverage
capacity of the vectors unchanged but reduces the Total Hamming Distance (THD) so that there is reduction in power
while shifting operation.
Abstract: The steam cracking reactions are always accompanied with the formation of coke which deposits on the walls of the tubular reactors. The investigation has attempted to control catalytic coking by the applying aluminum, zinc and ceramic coating like aluminum-magnesium by thermal spray and pack cementation method. Rate of coke formation during steam cracking of naphtha has been investigated both for uncoated stainless steel (with different alloys) and metal coating constructed with thermal Spray and pack cementation method with metal powders of Aluminum, Aluminum-Magnesium, zinc, silicon, nickel and chromium. The results of the study show that passivating the surface of SS321 with a coating of Aluminum and Aluminum-Magnesium can significantly reduce the rate of coke deposition during naphtha pyrolysis. SEM and EDAX techniques (Philips XL Series) were used to examine the coke deposits formed by the metal-hydrocarbon reactions. Our objective was to separate the different stages by identifying the characteristic morphologies.
Abstract: Fast development of technologies, economic globalization and many other external circumstances stimulate company’s competitiveness. One of the major trends in today’s business is the shift to the exploitation of the Internet and electronic environment for entrepreneurial needs. Latest researches confirm that e-environment provides a range of possibilities and opportunities for companies, especially for micro-, small- and medium-sized companies, which have limited resources. The usage of e-tools raises the effectiveness and the profitability of an organization, as well as its competitiveness.
In the electronic market, as in the classic one, there are factors, such as globalization, development of new technology, price sensitive consumers, Internet, new distribution and communication channels that influence entrepreneurship. As a result of eenvironment development, e-commerce and e-marketing grow as well.
Objective of the paper: To describe and identify factors influencing company’s competitiveness in e-environment.
Research methodology: The authors employ well-established quantitative and qualitative methods of research: grouping, analysis, statistics method, factor analysis in SPSS 20 environment, etc. The theoretical and methodological background of the research is formed by using scientific researches and publications, such as that from mass media and professional literature; statistical information from legal institutions as well as information collected by the authors during the surveying process.
Research result: The authors detected and classified factors influencing competitiveness in e-environment.
In this paper, the authors presented their findings based on theoretical, scientific, and field research. Authors have conducted a research on e-environment utilization among Latvian enterprises.
Abstract: This paper argues that increased uncertainty, in certain
situations, may actually encourage investment. Since earlier studies
mostly base their arguments on the assumption of geometric Brownian
motion, the study extends the assumption to alternative stochastic
processes, such as mixed diffusion-jump, mean-reverting process, and
jump amplitude process. A general approach of Monte Carlo
simulation is developed to derive optimal investment trigger for the
situation that the closed-form solution could not be readily obtained
under the assumption of alternative process. The main finding is that
the overall effect of uncertainty on investment is interpreted by the
probability of investing, and the relationship appears to be an invested
U-shaped curve between uncertainty and investment. The implication
is that uncertainty does not always discourage investment even under
several sources of uncertainty. Furthermore, high-risk projects are not
always dominated by low-risk projects because the high-risk projects
may have a positive realization effect on encouraging investment.
Abstract: On-line (near infrared) spectroscopy is widely used to support the operation of complex process systems. Information extracted from spectral database can be used to estimate unmeasured product properties and monitor the operation of the process. These techniques are based on looking for similar spectra by nearest neighborhood algorithms and distance based searching methods. Search for nearest neighbors in the spectral space is an NP-hard problem, the computational complexity increases by the number of points in the discrete spectrum and the number of samples in the database. To reduce the calculation time some kind of indexing could be used. The main idea presented in this paper is to combine indexing and visualization techniques to reduce the computational requirement of estimation algorithms by providing a two dimensional indexing that can also be used to visualize the structure of the spectral database. This 2D visualization of spectral database does not only support application of distance and similarity based techniques but enables the utilization of advanced clustering and prediction algorithms based on the Delaunay tessellation of the mapped spectral space. This means the prediction has not to use the high dimension space but can be based on the mapped space too. The results illustrate that the proposed method is able to segment (cluster) spectral databases and detect outliers that are not suitable for instance based learning algorithms.
Abstract: Silver nanoparticles were prepared by chemical reduction method. Silver nitrate was taken as the metal precursor and hydrazine hydrate as a reducing agent. The formation of the silver nanoparticles was monitored using UV-Vis absorption spectroscopy. The UV-Vis spectroscopy revealed the formation of silver nanopart├¡cles by exhibing the typical surface plasmon absorption maxima at 418-420 nm from the UV–Vis spectrum. Comparison of theoretical (Mie light scattering theory) and experimental results showed that diameter of silver nanoparticles in colloidal solution is about 60 nm. We have used energy-dispersive spectroscopy (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM) and, UV–Vis spectroscopy to characterize the nanoparticles obtained. The energy-dispersive spectroscopy (EDX) of the nanoparticles dispersion confirmed the presence of elemental silver signal no peaks of other impurity were detected. The average size and morphology of silver nanoparticles were determined by transmission electron microscopy (TEM). TEM photographs indicate that the nanopowders consist of well dispersed agglomerates of grains with a narrow size distribution (40 and 60 nm), whereas the radius of the individual particles are between 10 and 20 nm. The synthesized nanoparticles have been structurally characterized by X-ray diffraction and transmission high-energy electron diffraction (HEED). The peaks in the XRD pattern are in good agreement with the standard values of the face-centered-cubic form of metallic silver (ICCD-JCPDS card no. 4-0787) and no peaks of other impurity crystalline phases were detected. Additionally, the antibacterial activity of the nanopart├¡culas dispersion was measured by Kirby-Bauer method. The nanoparticles of silver showed high antimicrobial and bactericidal activity against gram positive bacteria such as Escherichia Coli, Pseudimonas aureginosa and staphylococcus aureus which is a highly methicillin resistant strain.
Abstract: In this article, a formal specification and verification of the Rabin public-key scheme in a formal proof system is presented. The idea is to use the two views of cryptographic verification: the computational approach relying on the vocabulary of probability theory and complexity theory and the formal approach based on ideas and techniques from logic and programming languages. A major objective of this article is the presentation of the first computer-proved implementation of the Rabin public-key scheme in Isabelle/HOL. Moreover, we explicate a (computer-proven) formalization of correctness as well as a computer verification of security properties using a straight-forward computation model in Isabelle/HOL. The analysis uses a given database to prove formal properties of our implemented functions with computer support. The main task in designing a practical formalization of correctness as well as efficient computer proofs of security properties is to cope with the complexity of cryptographic proving. We reduce this complexity by exploring a light-weight formalization that enables both appropriate formal definitions as well as efficient formal proofs. Consequently, we get reliable proofs with a minimal error rate augmenting the used database, what provides a formal basis for more computer proof constructions in this area.
Abstract: In this paper, an analytical approach for free vibration
analysis of rectangular and circular membranes is presented. The
method is based on wave approach. From wave standpoint vibration
propagate, reflect and transmit in a structure. Firstly, the propagation
and reflection matrices for rectangular and circular membranes are
derived. Then, these matrices are combined to provide a concise and
systematic approach to free vibration analysis of membranes.
Subsequently, the eigenvalue problem for free vibration of membrane
is formulated and the equation of membrane natural frequencies is
constructed. Finally, the effectiveness of the approach is shown by
comparison of the results with existing classical solution.
Abstract: In the current study, we have conducted an experimental investigation on the utilization of electronic arc furnace (EAF) reducing slag for the absorption of CO2 via wet grinding method. It was carried out by various grinding conditions. The slag was ground in the vibrating ball mill in the presence of CO2 and pure water under ambient temperature. The reaction behavior was monitored with constant pressure method, and the changes of experimental systems volume as a function of grinding time were measured. It was found that the CO2 absorption occurred as soon as the grinding started. The CO2 absorption was significantly increased in the case of wet grinding compare to the dry grinding. Generally, the amount of CO2 absorption increased as the amount of water, weight of slag and initial pressure increased. However, it was decreased when the amount of water exceeds 200ml and when smaller balls were used. The absorption of CO2 occurred simultaneously with the start of the grinding and it stopped when the grinding was stopped. According to this research, the CO2 reacted with the CaO inside the slag, forming CaCO3.
Abstract: This study aims to examine the factors affecting
knowledge sharing behavior in knowledge-based electronic communities (e-communities) because quantity and quality of
knowledge shared among the members play a critical role in the community-s sustainability. Past research has suggested three
perspectives that may affect the quantity and quality of knowledge
shared: economics, social psychology, and social ecology. In this
study, we strongly believe that an economic perspective may be suitable to validate factors influencing newly registered members-
knowledge contribution at the beginning of relationship development.
Accordingly, this study proposes a model to validate the factors influencing members- knowledge sharing based on Transaction Cost
Theory. By doing so, we may empirically test our hypotheses in various types of e-communities to determine the generalizability of our research models.