Abstract: Optical Intersatellite Links (OISLs) are wireless communications using optical signals to interconnect satellites. It is expected to be the next generation wireless communication technology according to its inherent characteristics like: an increased bandwidth, a high data rate, a data transmission security, an immunity to interference, and an unregulated spectrum etc. Optical space links are the best choice for the classical communication schemes due to its distinctive properties; high frequency, small antenna diameter and lowest transmitted power, which are critical factors to define a space communication. This paper discusses the development of free space technology and analyses the parameters and factors to establish a reliable intersatellite links using an optical signal to exchange data between satellites.
Abstract: Recently, fluidized bed gasification becomes an attractive technology for power generation due to its higher efficiency. The main objective pursued in this work is to investigate the producer gas production potential from sized biomass (sawdust and pigeon pea) by applying the air gasification technique. The size of the biomass selected for the study was in the range of 0.40-0.84 mm. An experimental study was conducted using a fluidized bed gasifier with 210 mm diameter and 1600 mm height. During the experiments, the fuel properties and the effects of operating parameters such as gasification temperatures 700 to 900 °C, equivalence ratio 0.16 to 0.46 were studied. It was concluded that substantial amounts of producer gas (up to 1110 kcal/m3) could be produced utilizing biomass such as sawdust and pigeon pea by applying this fluidization technique. For both samples, the rise of temperature till 900 °C and equivalence ratio of 0.4 favored further gasification reactions and resulted into producer gas with calorific value 1110 kcal/m3.
Abstract: This study discusses a simple solution for the problem of shortage in learning resources for kindergarten teachers. Occasionally, kindergarten teachers cannot access proper resources by usual search methods as libraries or search engines. Furthermore, these methods require a long time and efforts for preparing. The study is expected to facilitate accessing learning resources. Moreover, it suggests a potential direction for using QR code inside the classroom. The present work proposes that QR code can be used for digitizing kindergarten curriculums and accessing various learning resources. It investigates using QR code for saving information related to the concepts which kindergarten teachers use in the current educational situation. The researchers have established a guide for kindergarten teachers based on the Egyptian official curriculum. The guide provides different learning resources for each scientific and mathematical concept in the curriculum, and each learning resource is represented as a QR code image that contains its URL. Therefore, kindergarten teachers can use smartphone applications for reading QR codes and displaying the related learning resources for students immediately. The guide has been provided to a group of 108 teachers for using inside their classrooms. The results showed that the teachers approved the guide, and gave a good response.
Abstract: In recent years, a multi-antenna system is actively used
to improve the performance of the communication. A MIMO-OFDM
system can provide multiplexing gain or diversity gain. These gains
are obtained in proportion to the increase of the number of antennas.
In order to provide the optimal gain of the MIMO-OFDM system,
various transmission and reception schemes are presented. This paper
aims to propose a hybrid scheme that base station provides both
diversity gain and multiplexing gain at the same time.
Abstract: A designing of a structure requires its realization on rough or sloping ground. Besides the problem of the stability of the landslide, the behavior of the foundations that are bearing the structure is influenced by the destabilizing effect of the ground’s slope. This article focuses on the analysis of the slope stability exposed to loading by introducing the different factors influencing the slope’s behavior on the one hand, and on the influence of this slope on the foundation’s behavior on the other hand. This study is about the elastoplastic modelization using FLAC 2D. This software is based on the finite difference method, which is one of the older methods of numeric resolution of differential equations system with initial and boundary conditions. It was developed for the geotechnical simulation calculation. The aim of this simulation is to demonstrate the notable effect of shear modulus « G », cohesion « C », inclination angle (edge) « β », and distance between the foundation and the head of the slope on the stability of the slope as well as the stability of the foundation. In our simulation, the slope is constituted by homogenous ground. The foundation is considered as rigid/hard; therefore, the loading is made by the application of the vertical strengths on the nodes which represent the contact between the foundation and the ground.
Abstract: One of the major developments in machine learning in the past decade is the ensemble method, which finds highly accurate classifier by combining many moderately accurate component classifiers. In this research work, new ensemble classification methods are proposed with homogeneous ensemble classifier using bagging and heterogeneous ensemble classifier using arcing and their performances are analyzed in terms of accuracy. A Classifier ensemble is designed using Radial Basis Function (RBF) and Support Vector Machine (SVM) as base classifiers. The feasibility and the benefits of the proposed approaches are demonstrated by the means of standard datasets of intrusion detection. The main originality of the proposed approach is based on three main parts: preprocessing phase, classification phase, and combining phase. A wide range of comparative experiments is conducted for standard datasets of intrusion detection. The performance of the proposed homogeneous and heterogeneous ensemble classifiers are compared to the performance of other standard homogeneous and heterogeneous ensemble methods. The standard homogeneous ensemble methods include Error correcting output codes, Dagging and heterogeneous ensemble methods include majority voting, stacking. The proposed ensemble methods provide significant improvement of accuracy compared to individual classifiers and the proposed bagged RBF and SVM performs significantly better than ECOC and Dagging and the proposed hybrid RBF-SVM performs significantly better than voting and stacking. Also heterogeneous models exhibit better results than homogeneous models for standard datasets of intrusion detection.
Abstract: Patient satisfaction represents a crucial aspect in the evaluation of health care services. Preoperative teaching provides the patient with pertinent information concerning the surgical process and the intended surgical procedure as well as anticipated patient behavior (anxiety, fear), expected sensation, and the probable outcomes. Although patient education is part of Accreditation protocols, it is not uniform at most places. The aim of this study was to try to assess the benefit of preoperative patient education on selected post-operative outcome parameters; mainly, post-operative pain scores, requirement of additional analgesia, return to activity of daily living and overall patient satisfaction, and try to standardize few education protocols. Dependent variables were measured before and after the treatment on a study population of 302 volunteers. Educational intervention was provided by the Investigator in the preoperative period to the study group through personal counseling. An information booklet contained detailed information was also provided. Statistical Analysis was done using Chi square test, Mann Whitney u test and Fischer Exact Test on a total of 302 subjects. P value
Abstract: Cantilever beam is a simplified sample of a lot of mechanical components used in a wide range of applications, including many industries such as gas turbine blade. Due to the nature of the operating conditions, beams are subject to variety of damages especially crack propagates. Crack propagation may lead to catastrophic failure during operation. Therefore, online detection of crack presence and its propagation is very important and may reduce possible significant cost of the whole system failure. This paper aims to investigate the effect of cracks presence and crack propagation on one end fixed beam`s vibration. A finite element model will be developed for the blade in which the modal response of the structure with and without crack will be studied.
Abstract: The advanced concepts of strategic and innovation management in the sphere of company dynamic and innovation capabilities, and achieving their mutual alignment and a synergy effect, are important elements in business today. This paper analyses the theory and empirically investigates the influence of a company’s dynamic capabilities on its innovation capabilities. A new multidimensional model of dynamic capabilities is presented, consisting of five factors appropriate to real time requirements, while innovation capabilities are considered pursuant to the official OECD and Eurostat standards. After examination of dynamic and innovation capabilities indicated their theoretical links, the empirical study testing the model and examining the influence of a company’s dynamic capabilities on its innovation capabilities showed significant results. In the study, a research model was posed to relate company dynamic and innovation capabilities. One side of the model features the variables that are the determinants of dynamic capabilities defined through their factors, while the other side features the determinants of innovation capabilities pursuant to the official standards. With regard to the research model, five hypotheses were set. The study was performed in late 2014 on a representative sample of large and very large Croatian enterprises with a minimum of 250 employees. The research instrument was a questionnaire administered to company top management. For both variables, the position of the company was tested in comparison to industry competitors, on a fivepoint scale. In order to test the hypotheses, correlation tests were performed to determine whether there is a correlation between each individual factor of company dynamic capabilities with the existence of its innovation capabilities, in line with the research model. The results indicate a strong correlation between a company’s possession of dynamic capabilities in terms of their factors, due to the new multi-dimensional model presented in this paper, with its possession of innovation capabilities. Based on the results, all five hypotheses were accepted. Ultimately, it was concluded that there is a strong association between the dynamic and innovation capabilities of a company.
Abstract: This study focuses on the effect of pin taper tool ratio on friction stir welding of magnesium alloy AZ31. Two pieces of AZ31 alloy with thickness of 6 mm were friction stir welded by using the conventional milling machine. The shoulder diameter used in this experiment is fixed at 18 mm. The taper pin ratio used are varied at 6:6, 6:5, 6:4, 6:3, 6:2 and 6:1. The rotational speeds that were used in this study were 500 rpm, 1000 rpm and 1500 rpm, respectively. The welding speeds used are 150 mm/min, 200 mm/min and 250 mm/min. Microstructure observation of welded area was studied by using optical microscope. Equiaxed grains were observed at the TMAZ and stir zone indicating fully plastic deformation. Tool pin diameter ratio 6/1 causes low heat input to the material because of small contact surface between tool surface and stirred materials compared to other tool pin diameter ratio. The grain size of stir zone increased with increasing of ratio of rotational speed to transverse speed due to higher heat input. It is observed that worm hole is produced when excessive heat input is applied. To evaluate the mechanical properties of this specimen, tensile test was used in this study. Welded specimens using taper pin ratio 6:1 shows higher tensile strength compared to other taper pin ratio up to 204 MPa. Moreover, specimens using taper pin ratio 6:1 showed better tensile strength with 500 rpm of rotational speed and 150mm/min welding speed.
Abstract: This research provides a systematic way to study and
better understand double nano-tubular structure of alunina (Al2O3) and
titania (TiO2). The TiO2 NT was prepared by immersing Al2O3
template in 0.02 M titanium fluoride (TiF4) solution (pH=3) at 25 °C
for 120 min, followed by annealing at 450 °C for 1 h to obtain anatase
TiO2 NT in the Al2O3 template. Large-scale development of film for
nanotube-based CO2 capture and conversion can potentially result in
more efficient energy harvesting. In addition, the production process
will be relatively environmentally friendly. The knowledge generated
by this research will significantly advance research in the area of
Al2O3, TiO2, CaO, and Ca2O3 nano-structure film fabrication and
applications for CO2 capture and conversion. This green energy source
will potentially reduce reliance on carbon-based energy resources and
increase interest in science and engineering careers.
Abstract: Study of the effects of climate change on Norway
Spruce (Picea abies) forests has mainly focused on the diversity of
tree species diversity of tree species as a result of the ability of
species to tolerate temperature and moisture changes as well as some
effects of disturbance regime changes. The tree species’ diversity
changes in spruce forests due to climate change have been analyzed
via gap model. Forest gap model is a dynamic model for calculation
basic characteristics of individual forest trees. Input ecological data
for model calculations have been taken from the permanent research
plots located in primeval forests in mountainous regions in Slovakia.
The results of regional scenarios of the climatic change for the
territory of Slovakia have been used, from which the values are
according to the CGCM3.1 (global) model, KNMI and MPI
(regional) models. Model results for conditions of the climate change
scenarios suggest a shift of the upper forest limit to the region of the
present subalpine zone, in supramontane zone. N. spruce
representation will decrease at the expense of beech and precious
broadleaved species (Acer sp., Sorbus sp., Fraxinus sp.). The most
significant tree species diversity changes have been identified for the
upper tree line and current belt of dwarf pine (Pinus mugo)
occurrence. The results have been also discussed in relation to most
important disturbances (wind storms, snow and ice storms) and
phenological changes which consequences are little known. Special
discussion is focused on biomass production changes in relation to
carbon storage diversity in different carbon pools.
Abstract: This paper takes a philosophical view as axiom, and
reveals the relationship between information theory and Natural
Intelligence and Artificial Intelligence under real world conditions.
This paper also derives the relationship between natural intelligence
and nature. According to communication principle of information
theory, Natural Intelligence can be divided into real part and virtual
part. Based on information theory principle that Information does not
increase, the restriction mechanism of Natural Intelligence creativity is
conducted. The restriction mechanism of creativity reveals the limit of
natural intelligence and artificial intelligence. The paper provides a
new angle to observe natural intelligence and artificial intelligence.
Abstract: Social entrepreneurship is a new and exciting topic
that holds a great promise in helping alleviate the social problems of
the world. As a new subject, the meaning of the term is too broad and
this is counterproductive in trying to build understanding around the
concept. The purpose of this study is to identify and compare the
elements of social entrepreneurship as defined by seven international
organizations leading social entrepreneurship projects: Ashoka
Foundation, Skoll Foundation, Schwab Foundation and Yunus
Center; as well as from three other institutions fostering social
entrepreneurship: Global Social Benefit Institute, BRAC University,
and Socialab. The study used document analysis from Skoll
Foundation, Schwab Foundation, Yunus Center and Ashoka
Foundation; and open ended interview to experts from the Global
Social Benefit Institute at Santa Clara University in United States,
BRAC University from Bangladesh, and Socialab from Argentina.
The study identified three clearly differentiated schools of thought,
based on their views on revenue, scalability, replicability and
geographic location. While this study is by no means exhaustive, it
provides an indication of the patterns of ideas fostered by important
players in the field. By clearly identifying the similarities and
differences in the concept of social entrepreneurship, research and
practitioners are better equipped to build on the subject, and to
promote more adequate and accurate social policies to foster the
development of social entrepreneurship.
Abstract: Today, insurers may use the yield curve as an indicator
evaluation of the profit or the performance of their portfolios;
therefore, they modeled it by one class of model that has the ability
to fit and forecast the future term structure of interest rates. This class
of model is the Nelson-Siegel-Svensson model. Unfortunately, many
authors have reported a lot of difficulties when they want to calibrate
the model because the optimization problem is not convex and has
multiple local optima. In this context, we implement a hybrid Particle
Swarm optimization and Nelder Mead algorithm in order to minimize
by least squares method, the difference between the zero-coupon
curve and the NSS curve.
Abstract: In nearly all earthquakes of the past century that
resulted in moderate to significant damage, the occurrence of postearthquake
fire ignition (PEFI) has imposed a serious hazard and
caused severe damage, especially in urban areas. In order to reduce
the loss of life and property caused by post-earthquake fires, there is
a crucial need for predictive models to estimate the PEFI risk. The
parameters affecting PEFI risk can be categorized as: 1) factors
influencing fire ignition in normal (non-earthquake) condition,
including floor area, building category, ignitability, type of appliance,
and prevention devices, and 2) earthquake related factors contributing
to the PEFI risk, including building vulnerability and earthquake
characteristics such as intensity, peak ground acceleration, and peak
ground velocity. State-of-the-art statistical PEFI risk models are
solely based on limited available earthquake data, and therefore they
cannot predict the PEFI risk for areas with insufficient earthquake
records since such records are needed in estimating the PEFI model
parameters. In this paper, the correlation between normal condition
ignition risk, peak ground acceleration, and PEFI risk is examined in
an effort to offer a means for predicting post-earthquake ignition
events. An illustrative example is presented to demonstrate how such
correlation can be employed in a seismic area to predict PEFI hazard.
Abstract: Software vulnerabilities are increasing and not only impact services and processes availability as well as information confidentiality, integrity and privacy, but also cause changes that interfere in the development process. Security test could be a solution to reduce vulnerabilities. However, the variety of test techniques with the lack of real case studies of applying tests focusing on software development life cycle compromise its effective use. This paper offers an overview of how a Systematic Mapping Study (MS) about security verification, validation and test (VVT) was performed, besides presenting general results about this study.
Abstract: In this study, natural bentonite was used as natural
clay material and samples were taken from the Kalecik district in
Ankara. In this research, bentonite is the subject of an analysis from
standpoint of assessing the basic properties of engineered barriers
with respect to the buffer material. Bentonite and sand mixtures were
prepared for tests. Some of clay minerals give relatively higher
hydraulic conductivity and lower swelling pressure. Generally,
hydraulic conductivity of these type clays is lower than
Abstract: Introduction: Craniopharyngiomas (CPs) are rare epithelial tumors located mainly in the sellar/parasellar region. CPs have been classified histopathologically, genetically, clinically and prognostically into two distinctive subtypes: adamantinomatous and papillary variants. Aim: To examine the pattern of expression of both the β-catenin and epidermal growth factor receptor (EGFR) in surgically resected samples of adamantinomatous CP, and to asses for the possibility of using anti-EGFR in the management of ACP patients. Materials and methods: β-catenin and EGFR immunostaining was performed on paraffin-embedded tissue sections of 18 ACP cases. Result: 17 out of 18 cases (94%) of ACP exhibited strong nuclear/cytoplasmic expression of β-catenin, 15 (83%) of APC cases were positive for EGFR. Conclusion: Nuclear accumulation of β-catenin is a diagnostic hallmark of ACP. EGFR positivity in most cases of ACP could qualify the use of anti-EGFR therapy.
Abstract: Within Vietnam's system of higher education, its
schools of business play a vital role in supporting the country’s
economic objectives. However, the crucial contribution of soft skills
for maximal success within the business sector has to date not been
adequately recognized by its business schools. This being so, the
development of the business school curriculum in Vietnam has not
been able to 'catch up', so to say, with the burgeoning need of
students for a comprehensive soft skills program designed to meet the
national and global business objectives of their potential employers.
The burden of the present paper is first to reveal the results of our
survey in Vietnam which make explicit the extent to which major
Vietnamese industrial employers’ value the potential role that soft
skill competencies can play in maximizing business success. Our
final task will be to determine which soft skills employers discern as
best serving to maximize the economic interests of Vietnam within
the global marketplace. Semi-structured telephone interviews have
been conducted with the 15 representative Head Employers of
Vietnam's reputedly largest and most successful of the diverse
business enterprises across Vietnam. The findings of the study
indicate that all respondents highly value the increasing importance
of soft skills in business success. Our critical analysis of respondent
data reveals that 19 essential soft skills are deemed by employers as
integral to business workplace efficacy and should thus be integrated
into the formal business curriculum. We are confident that our study
represents the first comprehensive and specific survey yet undertaken
within the business sector in Vietnam which accesses and analyses
the opinions of representative employers from major companies
across the country in regard to the growing importance of 19 specific
soft skills essential for maximizing overall business success. Our
research findings also reveal that the integration into business school
curriculums nationwide of the soft skills we have identified is of
paramount importance to advance the national and global economic
interests of Vietnam.