Abstract: The basis of examines is survey of 500 in the years
2002-2010, which was selected according to homogeneity of land
cover and where 1090 revenues were evaluated. For achieved yields
of winter wheat is obtained multicriterial regression function
depending on the major factors influencing the consumption of
nitrogen. The coefficient of discrimination of the established model is
0.722. The increase in efficiency of fertilization is involved in supply
of organic nutrients, tillage, soil pH, past weather, the humus content
in the subsoil and grain content to 0.001 mm. The decrease in
efficiency was mainly influenced by the total dose of mineral
nitrogen, although it was divided into multiple doses, the proportion
loamy particles up to 0.01 mm, rainy, or conversely dry weather
during the vegetation. The efficiency of nitrogen was found to be the
smallest on undeveloped soils and the highest on chernozem and
alluvial soils.
Abstract: Nowadays, many manufacturing companies try to
reinforce their competitiveness or find a breakthrough by considering
collaboration. In Korea, more than 900 manufacturing companies are
using web-based collaboration systems developed by the
government-led project, referred to as i-Manufacturing. The system
supports some similar functions of Product Data Management (PDM)
as well as Project Management System (PMS). A web-based
collaboration system provides many useful functions for collaborative
works. This system, however, does not support new linking services
between buyers and suppliers. Therefore, in order to find new
collaborative partners, this paper proposes a framework which creates
new connections between buyers and suppliers facilitating their
collaboration, referred to as Excellent Manufacturer Scouting System
(EMSS). EMSS plays a role as a bridge between overseas buyers and
suppliers. As a part of study on EMSS, we also propose an evaluation
method of manufacturability of potential partners with six main factors.
Based on the results of evaluation, buyers may get a good guideline to
choose their new partners before getting into negotiation processes
with them.
Abstract: There are little subjects in macroeconomics that are so
widely discussed, but at the same time controversial and without a
clear solution such as the choice of exchange rate regime. National
authorities need to take into consideration numerous fundamentals,
trying to fulfil goals of economic growth, low and stable inflation
and international stability. This paper focuses on the countries of ex-
Yugoslavia and their exchange rate history as independent states. We
follow the development of the regimes in 6 countries during the
transition through the financial crisis of the second part of the 2000s
to the prospects of their final goal: full membership in the European
Union. Main question is to what extent has the exchange regime
contributed to their economic success, considering other objective
factors.
Abstract: The controllable electrical loss which consists of the
copper loss and iron loss can be minimized by the optimal control of
the armature current vector. The control algorithm of current vector
minimizing the electrical loss is proposed and the optimal current
vector can be decided according to the operating speed and the load
conditions. The proposed control algorithm is applied to the
experimental PM motor drive system and this paper presents a
modern approach of speed control for permanent magnet
synchronous motor (PMSM) applied for Electric Vehicle using a
nonlinear control. The regulation algorithms are based on the
feedback linearization technique. The direct component of the current
is controlled to be zero which insures the maximum torque operation.
The near unity power factor operation is also achieved. More over,
among EV-s motor electric propulsion features, the energy efficiency
is a basic characteristic that is influenced by vehicle dynamics and
system architecture. For this reason, the EV dynamics are taken into
account.
Abstract: Methane is the second most important greenhouse gas
(GHG) after carbon dioxide. Amount of methane emission from
energy sector is increasing day by day with various activities. In
present work, various sources of methane emission from upstream,
middle stream and downstream of oil & gas sectors are identified and
categorised as per IPCC-2006 guidelines. Data were collected from
various oil & gas sector like (i) exploration & production of oil & gas
(ii) supply through pipelines (iii) refinery throughput & production
(iv) storage & transportation (v) usage. Methane emission factors for
various categories were determined applying Tier-II and Tier-I
approach using the collected data. Total methane emission from
Indian Oil & Gas sectors was thus estimated for the year 1990 to
2007.
Abstract: The paper deals with the comparison study of
harmonic detection methods for a shunt active power filter. The
%THD and the power factor value at the PCC point after
compensation are considered for the comparison. There are three
harmonic detection methods used in the paper that are synchronous
reference frame method, synchronous detection method, and DQ axis
with Fourier method. In addition, the ideal current source is used to
represent the active power filter by assuming an infinitely fast
controller action of the active power filter. The simulation results
show that the DQ axis with Fourier method provides the minimum
%THD after compensation compared with other methods. However,
the power factor value at the PCC point after compensation is slightly
lower than that of synchronous detection method.
Abstract: In this paper, we rely on the story of the late British
weapons inspector David Kelly to illustrate how sensemaking can
inform the study of the ethics of suppression of dissent. Using
archival data, we reconstruct Dr. Kelly-s key responsibilities as a
weapons inspector and government employee. We begin by clarifying
the concept of dissent and how it is a useful organizational process.
We identify the various ways that dissent has been discussed in the
organizational literature and reconsider the process of sensemaking.
We conclude that suppression of opinions that deviate from the
majority is part of the identity maintenance of the sensemaking
process. We illustrate the prevention of dissent in organizations
consists of a set of unsatisfactory trade-offs.
Abstract: This study aims at investigating the empirical
relationships between risk preference, internet preference, and
internet knowledge which are known as user characteristics, in
addition to perceived risk of the customers on the internet purchase
intention. In order to test the relationships between the variables of
model 174, a questionnaire was collected from the students with
previous online experience. For the purpose of data analysis,
confirmatory factor analysis (CFA) and structural equation model
(SEM) was used.
Test results show that the perceived risk affects the internet
purchase intention, and increase or decrease of perceived risk
influences the purchase intention when the customer does the internet
shopping. Other factors such as internet preference, knowledge of the
internet, and risk preference affect the internet purchase intention.
Abstract: The proper selection of the AC-side passive filter
interconnecting the voltage source converter to the power supply is
essential to obtain satisfactory performances of an active power filter
system. The use of the LCL-type filter has the advantage of
eliminating the high frequency switching harmonics in the current
injected into the power supply. This paper is mainly focused on
analyzing the influence of the interface filter parameters on the active
filtering performances. Some design aspects are pointed out. Thus,
the design of the AC interface filter starts from transfer functions by
imposing the filter performance which refers to the significant current
attenuation of the switching harmonics without affecting the
harmonics to be compensated. A Matlab/Simulink model of the entire
active filtering system including a concrete nonlinear load has been
developed to examine the system performances. It is shown that a
gamma LC filter could accomplish the attenuation requirement of the
current provided by converter. Moreover, the existence of an optimal
value of the grid-side inductance which minimizes the total harmonic
distortion factor of the power supply current is pointed out.
Nevertheless, a small converter-side inductance and a damping
resistance in series with the filter capacitance are absolutely needed
in order to keep the ripple and oscillations of the current at the
converter side within acceptable limits. The effect of change in the
LCL-filter parameters is evaluated. It is concluded that good active
filtering performances can be achieved with small values of the
capacitance and converter-side inductance.
Abstract: This paper studies, maps and explains the interactions between downloaders and uploaders pertaining to the Internet film piracy. This study also covers several motivational factors that influence users to upload or download movies, and thus to engage in film piracy over the Internet. The essay also proposes a model that describes user behavior including their relationships and influences. Moreover, proposed theoretical interactions and motivational factors are applied to the real world scenario, using examples of a data storage webpage server Ulozto.net and webpage Piratebay.org gathering information about downloadable BitTorrents. Moreover, the theory is further supported by description of behavior of real Internet uploaders.
Abstract: A nonlinear optimal controller with a fuzzy gain
scheduler has been designed and applied to a Line-Of-Sight (LOS)
stabilization system. Use of Linear Quadratic Regulator (LQR)
theory is an optimal and simple manner of solving many control
engineering problems. However, this method cannot be utilized
directly for multigimbal LOS systems since they are nonlinear in
nature. To adapt LQ controllers to nonlinear systems at least a
linearization of the model plant is required. When the linearized
model is only valid within the vicinity of an operating point a gain
scheduler is required. Therefore, a Takagi-Sugeno Fuzzy Inference
System gain scheduler has been implemented, which keeps the
asymptotic stability performance provided by the optimal feedback
gain approach. The simulation results illustrate that the proposed
controller is capable of overcoming disturbances and maintaining a
satisfactory tracking performance.
Abstract: Based on a long-term vegetation index dataset of NDVI and meteorological data from 68 meteorological stations in the Qinghai-Tibet plateau and their relations with major climate factors were analyzed. The results show the following: 1) The linear trends of temperature in the Qinghai-Tibet plateau indicate that the temperature in the plateau generally increased, but it rose faster in the last 20 years. 2) The most significant NDVI increase occurred in the eastern and southern plateau. However, the western and northern plateau demonstrate a decreasing trend. 3) There is a significant positive linear correlation between NDVI and temperature and a negative correlation between NDVI and mean wind speed. However, no significant statistical relationship was found between NDVI and relative humidity, precipitation or sunshine duration.4) The changes in NDVI for the plateau are driven by temperature-precipitation, but for the desert and forest areas, the relation changes to precipitation-temperature-wind velocity and wind velocity-temperature-precipitation.
Abstract: In the crack growth analysis, the Stress Intensity
Factor (SIF) is a fundamental prerequisite. In the present study, the
mode I stress intensity factor (SIF) of three-dimensional penny-
Shaped crack is obtained in an isotropic elastic cylindrical medium
with arbitrary dimensions under arbitrary loading at the top of the
cylinder, by the semi-analytical method based on the Rayleigh-Ritz
method. This method that is based on minimizing the potential
energy amount of the whole of the system, gives a very close results
to the previous studies. Defining the displacements (elastic fields) by
hypothetical functions in a defined coordinate system is the base of
this research. So for creating the singularity conditions at the tip of
the crack the appropriate terms should be found.
Abstract: The daily increase of organic waste materials resulting
from different activities in the country is one of the main factors for
the pollution of environment. Today, with regard to the low level of
the output of using traditional methods, the high cost of disposal
waste materials and environmental pollutions, the use of modern
methods such as anaerobic digestion for the production of biogas has
been prevailing. The collected biogas from the process of anaerobic
digestion, as a renewable energy source similar to natural gas but
with a less methane and heating value is usable. Today, with the help
of technologies of filtration and proper preparation, access to biogas
with features fully similar to natural gas has become possible. At
present biogas is one of the main sources of supplying electrical and
thermal energy and also an appropriate option to be used in four
stroke engine, diesel engine, sterling engine, gas turbine, gas micro
turbine and fuel cell to produce electricity. The use of biogas for
different reasons which returns to socio-economic and environmental
advantages has been noticed in CHP for the production of energy in
the world. The production of biogas from the technology of anaerobic
digestion and its application in CHP power plants in Iran can not only
supply part of the energy demands in the country, but it can
materialize moving in line with the sustainable development. In this
article, the necessity of the development of CHP plants with biogas
fuels in the country will be dealt based on studies performed from the
economic, environmental and social aspects. Also to prove the
importance of the establishment of these kinds of power plants from
the economic point of view, necessary calculations has been done as
a case study for a CHP power plant with a biogas fuel.
Abstract: In recent years, a new numerical method has been
developed, the extended finite element method (X-FEM). The
objective of this work is to exploit the (X-FEM) for the treatment of
the fracture mechanics problems on 3D geometries, where we
showed the ability of this method to simulate the fatigue crack
growth into two cases: edge and central crack. In the results we
compared the six first natural frequencies of mode shapes uncracking
with the cracking initiation in the structure, and showed the stress
intensity factor (SIF) evolution function as crack size propagation
into structure, the analytical validation of (SIF) is presented. For to
evidence the aspects of this method, all result is compared between
FEA and X-FEM.
Abstract: The purpose of this investigation is to relate the rain
power and the overland flow power to soil erodibility to assess the
effects of both parameters on soil erosion using variable rainfall
intensity on remoulded agricultural soil. Six rainfall intensities were
used to simulate the natural rainfall and are as follows: 12.4mm/h,
20.3mm/h, 28.6mm/h, 52mm/h, 73.5mm/h and 103mm/h. The results
have shown that the relationship between overland flow power and
rain power is best represented by a linear function (R2=0.99). As
regards the relationships between soil erodibility factor and rain and
overland flow powers, the evolution of both parameters with the
erodibility factor follow a polynomial function with high coefficient
of determination. From their coefficients of determination (R2=0.95)
for rain power and (R2=0.96) for overland flow power, we can
conclude that the flow has more power to detach particles than rain.
This could be explained by the fact that the presence of particles,
already detached by rain and transported by the flow, give the flow
more weight and then contribute to the detachment of particles by
collision.
Abstract: Knowledge capabilities are increasingly important for
the innovative technology enterprises to enhance the business
performance in terms of product competitiveness, innovation and
sales. Recognition of the company capability by auditing allows them
to further pursue advancement, strategic planning and hence gain
competitive advantages. This paper attempts to develop an
Organizations- Knowledge Capabilities Assessment (OKCA) method
to assess the knowledge capabilities of technology companies. The
OKCA is a questionnaire-based assessment tool which has been
developed to uncover the impact of various knowledge capabilities on
different organizational performance. The collected data is then
analyzed to find out the crucial elements for different technological
companies. Based on the results, innovative technology enterprises are
able to recognize the direction for further improvement on business
performance and future development plan. External environmental
factors affecting organization performance can be found through the
further analysis of some selected reference companies.
Abstract: The innovative intelligent fuzzy weighted input
estimation method (FWIEM) can be applied to the inverse heat
transfer conduction problem (IHCP) to estimate the unknown
time-varying heat flux of the multilayer materials as presented in this
paper. The feasibility of this method can be verified by adopting the
temperature measurement experiment. The experiment modular may
be designed by using the copper sample which is stacked up 4
aluminum samples with different thicknesses. Furthermore, the
bottoms of copper samples are heated by applying the standard heat
source, and the temperatures on the tops of aluminum are measured by
using the thermocouples. The temperature measurements are then
regarded as the inputs into the presented method to estimate the heat
flux in the bottoms of copper samples. The influence on the estimation
caused by the temperature measurement of the sample with different
thickness, the processing noise covariance Q, the weighting factor γ ,
the sampling time interval Δt , and the space discrete interval Δx ,
will be investigated by utilizing the experiment verification. The
results show that this method is efficient and robust to estimate the
unknown time-varying heat input of the multilayer materials.
Abstract: The high temperature degree and uniform
Temperature Distribution (TD) on surface of cookware which contact
with food are effective factors for improving cookware application.
Additionally, the ability of pan material in retaining the heat and nonreactivity
with foods are other significant properties. It is difficult for
single material to meet a wide variety of demands such as superior
thermal and chemical properties. Multi-Layer Plate (MLP) makes
more regular TD. In this study the main objectives are to find the best
structure (single or multi-layer) and materials to provide maximum
temperature degree and uniform TD up side surface of pan. And also
heat retaining of used metals with goal of improving the thermal
quality of pan to economize the energy. To achieve this aim were
employed Finite Element Method (FEM) for analyzing transient
thermal behavior of applied materials. The analysis has been
extended for different metals, we achieved the best temperature
profile and heat retaining in Copper/ Stainless Steel MLP.
Abstract: Use of fly ash as a supplementary cementing material
in large volumes can bring both technological and economic benefits
for concrete industry. In this investigation mix proportions for high
volume fly ash concrete were determined at cement replacement
levels of 50%, 55%, 60% and 65% with low calcium fly ash. Flexural
and compressive strengths of different mixes were measured at ages
of 7, 28 and 90 days. Flexural strength of composite section prepared
from pavement quality and lean high volume fly ash concrete was
determined at the age of 28 days. High volume fly ash concrete mixes
exhibited higher rate of strength gain and age factors than
corresponding reference concrete mixes. The optimum cement
replacement level for pavement quality concrete was found to be
60%. The consideration of bond between pavement quality and lean
of high volume fly ash concrete will be beneficial in design of rigid
pavements.