Abstract: Chemical vapor deposition method was used to
produce carbon nanotubes on an iron based catalyst from acetylene.
Gas-phase samples collected from the different positions of the tubular reactor were analyzed by GC/MS. A variety of species ranging from hydrogen to naphthalene were observed and changes in their concentrations were plotted against the reactor position. Briefly benzene, toluene, styrene, indene and naphthalene were the main
higher molecular weight species and vinylacetylene and diacetylene were the important intermediates. Nanotube characterization was performed by scanning electron microscopy and transmission electron microscopy.
Abstract: The VoIP networks as alternative method to traditional PSTN system has been implemented in a wide variety of structures
with multiple protocols, codecs, software and hardware–based
distributions. The use of cryptographic techniques let the users to have a secure communication, but the calculate throughput as well as the QoS parameters are affected according to the used algorithm. This
paper analyzes the VoIP throughput and the QoS parameters with
different commercial encryption methods. The measurement–based
approach uses lab scenarios to simulate LAN and WAN
environments. Security mechanisms such as TLS, SIAX2, SRTP,
IPSEC and ZRTP are analyzed with μ-LAW and GSM codecs.
Abstract: In the context of spectrum surveillance, a new method
to recover the code of spread spectrum signal is presented, while the
receiver has no knowledge of the transmitter-s spreading sequence. In
our previous paper, we used Genetic algorithm (GA), to recover
spreading code. Although genetic algorithms (GAs) are well known
for their robustness in solving complex optimization problems, but
nonetheless, by increasing the length of the code, we will often lead
to an unacceptable slow convergence speed. To solve this problem we
introduce Particle Swarm Optimization (PSO) into code estimation in
spread spectrum communication system. In searching process for
code estimation, the PSO algorithm has the merits of rapid
convergence to the global optimum, without being trapped in local
suboptimum, and good robustness to noise. In this paper we describe
how to implement PSO as a component of a searching algorithm in
code estimation. Swarm intelligence boasts a number of advantages
due to the use of mobile agents. Some of them are: Scalability, Fault
tolerance, Adaptation, Speed, Modularity, Autonomy, and
Parallelism. These properties make swarm intelligence very attractive
for spread spectrum code estimation. They also make swarm
intelligence suitable for a variety of other kinds of channels. Our
results compare between swarm-based algorithms and Genetic
algorithms, and also show PSO algorithm performance in code
estimation process.
Abstract: For a variety of safety and economic reasons, engineering undergraduates in Australia have experienced diminishing access to the real hardware that is typically the embodiment of their theoretical studies. This trend will delay the development of practical competence, decrease the ability to model and design, and suppress motivation. The author has attempted to address this concern by creating a software tool that contains both photographic images of real machinery, and sets of graphical modeling 'tools'. Academics from a range of disciplines can use the software to set tutorial tasks, and incorporate feedback comments for a range of student responses. An evaluation of the software demonstrated that students who had solved modeling problems with the aid of the electronic tutor performed significantly better in formal examinations with similar problems. The 2-D graphical diagnostic routines in the Tutor have the potential to be used in a wider range of problem-solving tasks.
Abstract: It-s known that incorporating prior knowledge into support
vector regression (SVR) can help to improve the approximation
performance. Most of researches are concerned with the incorporation
of knowledge in form of numerical relationships. Little work,
however, has been done to incorporate the prior knowledge on the
structural relationships among the variables (referred as to Structural
Prior Knowledge, SPK). This paper explores the incorporation of SPK
in SVR by constructing appropriate admissible support vector kernel
(SV kernel) based on the properties of reproducing kernel (R.K).
Three-levels specifications of SPK are studies with the corresponding
sub-levels of prior knowledge that can be considered for the method.
These include Hierarchical SPK (HSPK), Interactional SPK (ISPK)
consisting of independence, global and local interaction, Functional
SPK (FSPK) composed of exterior-FSPK and interior-FSPK. A
convenient tool for describing the SPK, namely Description Matrix
of SPK is introduced. Subsequently, a new SVR, namely Motivated
Support Vector Regression (MSVR) whose structure is motivated
in part by SPK, is proposed. Synthetic examples show that it is
possible to incorporate a wide variety of SPK and helpful to improve
the approximation performance in complex cases. The benefits of
MSVR are finally shown on a real-life military application, Air-toground
battle simulation, which shows great potential for MSVR to
the complex military applications.
Abstract: Human genome is not only the evolutionary
summation of all advantageous events, but also houses lesions of
deleterious foot prints. A single gene mutation sometimes may
express multiple consequences in numerous tissues and a linear
relationship of the genotype and the phenotype may often be obscure.
ß Thalassemia minor, a transfusion independent mild anaemia,
coupled with environment among other factors may articulate into
phenotypic pleotropy with Hypocholesterolemia, Vitamin D
deficiency, Tissue hypoxia, Hyper-parathyroidism and Psychological
alterations. Occurrence of Pancreatic insufficiency, resultant
steatorrhoea, Vitamin-D (25-OH) deficiency (13.86 ngm/ml) with
Hypocholesterolemia (85mg/dl) in a 30 years old male ß Thal-minor
patient (Hemoglobin 11mg/dl with Fetal Hemoglobin 2.10%, Hb A2
4.60% and Hb Adult 84.80% and altered Hemogram) with increased
Para thyroid hormone (62 pg/ml) & moderate Serum Ca+2
(9.5mg/ml) indicate towards a cascade of phenotypic pleotropy
where the ß Thalassemia mutation ,be it in the 5’ cap site of the
mRNA , differential splicing etc in heterozygous state is effecting
several metabolic pathways. Compensatory extramedulary
hematopoiesis may not coped up well with the stressful life style of
the young individual and increased erythropoietic stress with high
demand for cholesterol for RBC membrane synthesis may have
resulted in Hypocholesterolemia.Oxidative stress and tissue hypoxia
may have caused the pancreatic insufficiency, leading to Vitamin D
deficiency. This may in turn have caused the secondary
hyperparathyroidism to sustain serum Calcium level. Irritability and
stress intolerance of the patient was a cumulative effect of the vicious
cycle of metabolic compromises. From these findings we propose
that the metabolic deficiencies in the ß Thalassemia mutations may
be considered as the phenotypic display of the pleotropy to explain
the genetic epidemiology.
According to the recommendations from the NIH Workshop on
Gene-Environment Interplay in Common Complex Diseases: Forging
an Integrative Model, study design of observations should be
informed by gene-environment hypotheses and results of a study
(genetic diseases) should be published to inform future hypotheses.
Variety of approaches is needed to capture data on all possible
aspects, each of which is likely to contribute to the etiology of
disease. Speakers also agreed that there is a need for development of
new statistical methods and measurement tools to appraise
information that may be missed out by conventional method where
large sample size is needed to segregate considerable effect.
A meta analytic cohort study in future may bring about significant
insight on to the title comment.
Abstract: The physical methods for RNA secondary structure prediction are time consuming and expensive, thus methods for computational prediction will be a proper alternative. Various algorithms have been used for RNA structure prediction including dynamic programming and metaheuristic algorithms. Musician's behaviorinspired harmony search is a recently developed metaheuristic algorithm which has been successful in a wide variety of complex optimization problems. This paper proposes a harmony search algorithm (HSRNAFold) to find RNA secondary structure with minimum free energy and similar to the native structure. HSRNAFold is compared with dynamic programming benchmark mfold and metaheuristic algorithms (RnaPredict, SetPSO and HelixPSO). The results showed that HSRNAFold is comparable to mfold and better than metaheuristics in finding the minimum free energies and the number of correct base pairs.
Abstract: In the traditional buckling analysis of rectangular
plates the classical thin plate theory is generally applied, so
neglecting the plating shear deformation. It seems quite clear that this
method is not totally appropriate for the analysis of thick plates, so
that in the following the two variable refined plate theory proposed
by Shimpi (2006), that permits to take into account the transverse
shear effects, is applied for the buckling analysis of simply supported
isotropic rectangular plates, compressed in one and two orthogonal
directions.
The relevant results are compared with the classical ones and, for
rectangular plates under uniaxial compression, a new direct
expression, similar to the classical Bryan-s formula, is proposed for
the Euler buckling stress.
As the buckling analysis is a widely diffused topic for a variety of
structures, such as ship ones, some applications for plates uniformly
compressed in one and two orthogonal directions are presented and
the relevant theoretical results are compared with those ones obtained
by a FEM analysis, carried out by ANSYS, to show the feasibility of
the presented method.
Abstract: Packing problems arise in a wide variety of application
areas. The basic problem is that of determining an efficient arrangement
of different objects in a region without any overlap and
with minimal wasted gap between shapes. This paper presents a
novel population based approach for optimizing arrangement of irregular
shapes. In this approach, each shape is coded as an agent and
the agents' reproductions and grouping policies results in arrangements
of the objects in positions with least wasted area between
them. The approach is implemented in an application for cutting
sheets and test results on several problems from literature are presented.
Abstract: A major goal of any enterprise is to create a ratings
system of customer satisfaction, goods and services. It is obvious that
the company cannot change what is not measured. In order to get a
clearer picture of the preferences of the major consumer groups, this
stage should be based on extensive research, including a variety of
interviews and surveys. It is necessary to know the key benefits,
which determine customer satisfaction in the market segment, of the
properties of certain goods and services. It is important to estimate
the terms of these preferences from the viewpoint of the client. This
article discusses the importance of customer satisfaction, and ways of
assessing it.
Abstract: The Far From Most Strings Problem (FFMSP) is to obtain a string which is far from as many as possible of a given set of strings. All the input and the output strings are of the same length, and two strings are said to be far if their hamming distance is greater than or equal to a given positive integer. FFMSP belongs to the class of sequences consensus problems which have applications in molecular biology. The problem is NP-hard; it does not admit a constant-ratio approximation either, unless P = NP. Therefore, in addition to exact and approximate algorithms, (meta)heuristic algorithms have been proposed for the problem in recent years. On the other hand, in the recent years, hybrid algorithms have been proposed and successfully used for many hard problems in a variety of domains. In this paper, a new metaheuristic algorithm, called Constructive Beam and Local Search (CBLS), is investigated for the problem, which is a hybridization of constructive beam search and local search algorithms. More specifically, the proposed algorithm consists of two phases, the first phase is to obtain several candidate solutions via the constructive beam search and the second phase is to apply local search to the candidate solutions obtained by the first phase. The best solution found is returned as the final solution to the problem. The proposed algorithm is also similar to memetic algorithms in the sense that both use local search to further improve individual solutions. The CBLS algorithm is compared with the most recent published algorithm for the problem, GRASP, with significantly positive results; the improvement is by order of magnitudes in most cases.
Abstract: There is a variety of inconsistencies in the differences
in alcohol use and related problems between male and female
genders. This study was aimed at analyzing the gender differences in
alcohol use and related problems among university students in
Minsk, Belarus. A total of 465 male (average age of 21) and 1030
female (average age of 20.5) students from four major universities in
Minsk, Belarus were administered WHO recommended standardized
screening instruments – AUDIT, MAST, CAGE questionnaire, as
well as other alcohol related questions. The male to female ratio for
the prevalence of alcohol problems according to the AUDIT was
3.34, while the ratio for alcohol users was 0.97. There are a wide
gender differences in the pattern of alcohol use and preference for
different alcoholic beverages, cause for drinking, and other alcohol
related problems like injuries and blackouts.
Abstract: Small-scale RC models of both piles and tunnel ducts
were produced as mockups of reality and loaded under soil
confinement conditionsto investigate the damage evolution of
structural RC interacting with soil. Experimental verifications usinga
3D nonlinear FE analysis program called COM3D, which was
developed at the University of Tokyo, are introduced. This analysis
has been used in practice for seismic performance assessment of
underground ducts and in-ground LNG storage tanks in consideration
of soil-structure interactionunder static and dynamic loading. Varying
modes of failure of RCpilessubjected to different magnitudes of soil
confinement were successfully reproduced in the proposed small-scale
experiments and numerically simulated as well. Analytical simulation
was applied to RC tunnel mockups under a wide variety of depth and
soil confinement conditions, and reasonable matching was confirmed.
Abstract: Many of the compounds present in potato are important because of their beneficial effects on health, therefore, are highly desirable in the human diet. Potato tubers contain significant amounts of anthocyanins. The aim of this research was to determine the content of anthocyanins and its relationship with the colour of organically and conventionally cultivated potato varieties. In the research eight potato samples of three potato varieties were analyzed on anthocyanins, dry matter content and color. Obtained results show that there was no significant influence on amount of anthocyanins between different cultivation environments (p>0.05) while between varieties – significant difference (p
Abstract: There is wide range of scientific workflow systems
today, each one designed to resolve problems at a specific level. In
large collaborative projects, it is often necessary to recognize the
heterogeneous workflow systems already in use by various partners
and any potential collaboration between these systems requires
workflow interoperability. Publish/Subscribe Scientific Workflow
Interoperability Framework (PS-SWIF) approach was proposed to
achieve workflow interoperability among workflow systems. This
paper evaluates the PS-SWIF approach and its system to achieve
workflow interoperability using Web Services with asynchronous
notification messages represented by WS-Eventing standard. This
experiment covers different types of communication models provided
by Workflow Management Coalition (WfMC). These models are:
Chained processes, Nested synchronous sub-processes, Event
synchronous sub-processes, and Nested sub-processes
(Polling/Deferred Synchronous). Also, this experiment shows the
flexibility and simplicity of the PS-SWIF approach when applied to a
variety of workflow systems (Triana, Taverna, Kepler) in local and
remote environments.
Abstract: The supply chains (SCs) have to appeal to new management paradigms to improve their ability to respond rapidly and cost effectively to unpredictable changes in markets and increasing levels of environmental turbulence, both in terms of volume and variety. In this highly demanded context, the Agile paradigm provides the capabilities to SC quickly adapt to changes in the market requirements. The purpose of this paper is to suggest an Agile Index to assess the agility of the automotive companies and corresponding SCs. The proposed integrated assessment model incorporates Agile practices weighted according to their importance to the automotive SC competitiveness and obtained from the Delphi technique.
Abstract: From food consumption surveys has been found that potato consumption comparing to other European countries is one of the highest. Hence acrylamide (AA) intake coming from fried potatoes in population might be high as well. The aim of the research was to determine acrylamide content and estimate intake of acrylamide from roasted potatoes bred and cultivated in Latvia. Five common Latvian potato varieties were selected: Lenora, Brasla, Imanta, Zile, and Madara. A two-year research was conducted during two periods: just after harvesting and after six months of storage. Time and temperature (210 ± 5°C) was recorded during frying. AA was extracted from potatoes by solid phase extraction and AA content was determined by LC-MS/MS. estimated intake of acrylamide ranges from 0.012 to 0.496μgkg-1 BW per day.
Abstract: This paper describes a segmentation algorithm based
on the cooperation of an optical flow estimation method with edge
detection and region growing procedures.
The proposed method has been developed as a pre-processing
stage to be used in methodologies and tools for video/image indexing
and retrieval by content. The addressed problem consists in
extracting whole objects from background for producing images of
single complete objects from videos or photos. The extracted images
are used for calculating the object visual features necessary for both
indexing and retrieval processes.
The first task of the algorithm exploits the cues from motion
analysis for moving area detection. Objects and background are then
refined using respectively edge detection and region growing
procedures. These tasks are iteratively performed until objects and
background are completely resolved.
The developed method has been applied to a variety of indoor and
outdoor scenes where objects of different type and shape are
represented on variously textured background.
Abstract: In this paper, the direct AnsAz method is used for constructing the multi-wave solutions to the (2+1)-dimensional extension of the Korteweg de-Vries (shortly EKdV) equation. A new breather type of three-wave solutions including periodic breather type soliton solution, breather type of two-solitary solution are obtained. Some cases with specific values of the involved parameters are plotted for each of the three-wave solutions. Mechanical features of resonance interaction among the multi-wave are discussed. These results enrich the variety of the dynamics of higher-dimensional nonlinear wave field.
Abstract: One astonishing capability of humans is to recognize thousands of different objects visually, and to learn the semantic association between those objects and words referring to them. This work is an attempt to build a computational model of such capacity,simulating the process by which infants learn how to recognize objects and words through exposure to visual stimuli and vocal sounds.One of the main fact shaping the brain of a newborn is that lights and colors come from entities of the world. Gradually the visual system learn which light sensations belong to same entities, despite large changes in appearance. This experience is common between humans and several other mammals, like non-human primates. But humans only can recognize a huge variety of objects, most manufactured by himself, and make use of sounds to identify and categorize them. The aim of this model is to reproduce these processes in a biologically plausible way, by reconstructing the essential hierarchy of cortical circuits on the visual and auditory neural paths.