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: Slope stability analyses are largely carried out by deterministic methods and evaluated through a single security factor. Although it is known that the geotechnical parameters can present great dispersal, such analyses are considered fixed and known. The probabilistic methods, in turn, incorporate the variability of input key parameters (random variables), resulting in a range of values of safety factors, thus enabling the determination of the probability of failure, which is an essential parameter in the calculation of the risk (probability multiplied by the consequence of the event). Among the probabilistic methods, there are three frequently used methods in geotechnical society: FOSM (First-Order, Second-Moment), Rosenblueth (Point Estimates) and Monte Carlo. This paper presents a comparison between the results from deterministic and probabilistic analyses (FOSM method, Monte Carlo and Rosenblueth) applied to a hypothetical slope. The end was held to evaluate the behavior of the slope and consequent risk analysis, which is used to calculate the risk and analyze their mitigation and control solutions. It can be observed that the results obtained by the three probabilistic methods were quite close. It should be noticed that the calculation of the risk makes it possible to list the priority to the implementation of mitigation measures. Therefore, it is recommended to do a good assessment of the geological-geotechnical model incorporating the uncertainty in viability, design, construction, operation and closure by means of risk management.
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: 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: Negative pressures of liquids have been expected to contribute many kinds of technology. Nevertheless, experiments for subjecting liquids which have not too small volumes to negative pressures are difficult even now. The reason of the difficulties is because the liquids tend to generate cavities easily. In order to remove cavitation nuclei, an apparatus for enclosing water into a metal Berthelot tube under vacuum conditions was developed. By using the apparatus, negative pressures for water rose to ca. -20 MPa. This is the highest value for water in metal Berthelot tubes. Results were explained by a traditional crevice model. Keywords
Abstract: Superstructures like offshore platforms, tall buildings, transition towers, skyscrapers and bridges are normally designed to resist compression, uplift and lateral forces from wind waves, negative skin friction, ship impact and other applied loads. Better understanding and the precise simulation of the response of batter piles under the action of independent uplift loads is a vital topic and an area of active research in the field of geotechnical engineering. This paper investigates the use of finite element code (FEC) to examine the behaviour of model batter piles penetrated in dense sand, subjected to pull-out pressure by means of numerical modelling. The concept of the Winkler Model (beam on elastic foundation) has been used in which the interaction between the pile embedded depth and adjacent soil in the bearing zone is simulated by nonlinear p-y curves. The analysis was conducted on different pile slenderness ratios (lc⁄d) ranging from 7.5, 15.22 and 30 respectively. In addition, the optimum batter angle for a model steel pile penetrated in dense sand has been chosen to be 20° as this is the best angle for this simulation as demonstrated by other researcher published in literature. In this numerical analysis, the soil response is idealized as elasto-plastic and the model piles are described as elastic materials for the purpose of simulation. The results revealed that the applied loads affect the pullout pile capacity as well as the lateral pile response for dense sand together with varying shear strength parameters linked to the pile critical depth. Furthermore, the pile pull-out capacity increases with increasing the pile aspect ratios.
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: 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.
Abstract: Connected vehicles are equipped with wireless sensors
that aid in Vehicle to Vehicle (V2V) and Vehicle to Infrastructure
(V2I) communication. These vehicles will in the near future
provide road safety, improve transport efficiency, and reduce traffic
congestion. One of the challenges for connected vehicles is how
to ensure that information sent across the network is secure. If
security of the network is not guaranteed, several attacks can occur,
thereby compromising the robustness, reliability, and efficiency of
the network. This paper discusses existing security mechanisms and
unique properties of connected vehicles. The methodology employed
in this work is exploratory. The paper reviews existing security
solutions for connected vehicles. More concretely, it discusses
various cryptographic mechanisms available, and suggests areas
of improvement. The study proposes a combination of symmetric
key encryption and public key cryptography to improve security.
The study further proposes message aggregation as a technique to
overcome message redundancy. This paper offers a comprehensive
overview of connected vehicles technology, its applications, its
security mechanisms, open challenges, and potential areas of future
research.
Abstract: The technological paradigm of the disaster
management field, especially in the case of governmental
intervention strategies, is generally based on rapid and flexible
accommodation solutions. From various technical solution patterns
used to address the immediate housing needs of disaster victims, the
adaptive re-use of existing buildings can be considered to be both
low-cost and practical. However, there is a scarcity of analytical
methods to screen, select and adapt buildings to help decision makers
in cases of emergency. Following an extensive literature review, this
paper aims to highlight key points and problem areas associated with
the adaptive re-use of buildings within the disaster management
context. In other disciplines such as real estate management, the
adaptive re-use potential (ARP) of existing buildings is typically
based on the prioritization of a set of technical and non-technical
criteria which are then weighted to arrive at an economically viable
investment decision. After a disaster, however, the assessment of the
ARP of buildings requires consideration of different/additional layers
of analysis which stem from general disaster management principles
and the peculiarities of different types of disasters, as well as of their
victims. In this paper, a discussion of the development of an adaptive
re-use potential (ARP) assessment model is presented. It is thought
that governmental and non-governmental decision makers who are
required to take quick decisions to accommodate displaced masses
following disasters are likely to benefit from the implementation of
such a model.
Abstract: Imazu Bay plays an important role for endangered
species such as horseshoe crabs and black-faced spoonbills that stay in
the bay for spawning or the passing of winter. However, this bay is
semi-enclosed with slow water exchange, which could lead to
eutrophication under the condition of excess nutrient inflow to the bay.
Therefore, quantification of nutrient inflow is of great importance.
Generally, analysis of nutrient inflow to the bays takes into
consideration nutrient inflow from only the river, but that from
groundwater should not be ignored for more accurate results. The main
objective of this study is to estimate the amounts of nutrient inflow
from river and groundwater to Imazu Bay by analyzing water budget
in Zuibaiji River Basin and loads of T-N, T-P, NO3-N and NH4-N. The
water budget computation in the basin is performed using groundwater
recharge model and quasi three-dimensional two-phase groundwater
flow model, and the multiplication of the measured amount of nutrient
inflow with the computed discharge gives the total amount of nutrient
inflow to the bay. In addition, in order to evaluate nutrient inflow to the
bay, the result is compared with nutrient inflow from geologically
similar river basins. The result shows that the discharge is 3.50×107
m3/year from the river and 1.04×107 m3/year from groundwater. The
submarine groundwater discharge accounts for approximately 23 % of
the total discharge, which is large compared to the other river basins. It
is also revealed that the total nutrient inflow is not particularly large.
The sum of NO3-N and NH4-N loadings from groundwater is less than
10 % of that from the river because of denitrification in groundwater.
The Shin Seibu Sewage Treatment Plant located below the observation
points discharges treated water of 15,400 m3/day and plans to increase
it. However, the loads of T-N and T-P from the treatment plant are 3.9
mg/L and 0.19 mg/L, so that it does not contribute a lot to
eutrophication.
Abstract: This study was designed to evaluate whether carvacrol
(CAR) could provide protection against lung injury by acute
pancreatitis development. The rats were randomized into groups to
receive (I) no therapy; (II) 50 μg/kg cerulein at 1h intervals by four
intraperitoneal injections (i.p.); (III) 50, 100 and 200 mg/kg CAR by
one i.p.; and (IV) cerulein+CAR after 2h of cerulein injection. 12h
later, serum samples were obtained to assess pancreatic function the
lipase and amylase values. The animals were euthanized and lung
samples were excised. The specimens were stained with
hematoxylin-eosin (H&E), periodic acid–Schif (PAS), Mallory's
trichrome and amyloid. Additionally, oxidative DNA damage was
determined by measuring as increases in 8-hydroxy-deoxyguanosine
(8-OH-dG) adducts. The results showed that the serum activity of
lipase and amylase in AP rats were significantly reduced after the
therapy (p