WCOT: A utility based lifetime metric for wireless sensor networks

Network lifetime is a novel performance metric which is derived in need to evaluate the networks that are composed of nodes with non-replenishable energy sources. Wireless Sensor Networks (WSNs) are the primary examples of such networks, in which elongating the network lifetime is the main concern. Optimal WSN design is highly dependent on the application scenario context. Correct quantification of the application specific network lifetime is a must to further optimize the design or to comparatively evaluate the proposed schemes – e.g. a legacy layered design vs. a cross-layer implementation. However, in practice, we observe that the focus is given on proposing sophisticated schemes to increase the energy efficiency, whereas only rudimentary lifetime metrics are employed to evaluate the outcome of this effort which compromises the correctness of the results. To realistically and correctly quantify the lifetime, we propose a utility based lifetime measurement framework called Weighted Cumulative Operational Time (WCOT). WCOT lets users incorporate the application dependence into the lifetime metric through its utility based interface. WCOT performs a weighted summation of time where utility values are the weights. With this mechanism, a more representative lifetime metric which maps the complete network behavior into a numeric value is obtained. This is in contrast with metrics which focus solely on certain milestones of the network functionality to quantify the lifetime which include the first node death, the last node death.     

A Comparative Study on Changes and Relationships of Kernel Biochemical Components in Different Types of Maize

A great deal of genetic variability and breeding efforts have yielded a number of specialty maize types. Little is known about how the off‐target traits in specialty maize kernel have changed and how they compare to those of standard maize genotypes. In this study, we compared the normal (NORMAL), high‐oil (HOM) and high‐protein maize (HPM) genotypes in terms of oil, protein, fatty acids and some mineral components. We also investigated the relationships among the evaluated traits in different kernel types. We detected a significant variation among the maize types for all of the investigated traits. Specialty maize genotypes had a superior performance for the traits they were specifically bred for, as well as kernel mineral content over the normal genotypes. HOM and HPM had similar values in terms of their fatty acid composition. However, they were different from the standard genotypes, with higher oleic and lower linolenic acid levels, which indicates that the specialty maize genotypes possess a better oil quality. Correlation analysis revealed that only three pairs of correlations out of 46 values had the same sign and a similar level of significance in different types. Such similarities or differences in correlation values for different types should be taken into account in the efforts for developing high quality maize genotypes.     

Quality assessment of surface and groundwater in Solaklı Basin (Trabzon, Turkey)

The paper reports a study of the surface and ground water in Solakl? Basin, Trabzon, from an assessment of 33 sampling points. Many of the parameters analysed are only marginally acceptable as potable water, even though the samples were collected during the wet season. The highest concentrations of contaminants were found downstream of the centres of population. The results indicate regular monitoring is required and some measures should be taken to protect the limited resources.     

Adsorption of lead and copper on bentonite and grapeseed activated carbon in single- and binary-ion systems

In this study, bentonite originating from Turkey (Eski?ehir province) and activated carbon obtained from grapeseed were used as adsorbents for the removal of lead (Pb²⁺) and copper (Cu²⁺) ions from aqueous solutions. Experiments were performed in single- and binary-ion systems at constant temperature of 298 K and pH value of 5. In order to describe the adsorption mechanism Langmuir, Freundlich and Temkin isotherms were used. The total adsorption capacity values of adsorbents were compared. It was observed that the total adsorption capacity values were changed depending on the type of adsorbent used, type of metal ion and interaction between metal ions.     

Specific Energy Prediction for Circular Diamond Saw in Cutting Different Types of Rocks Using Multivariable Linear Regression Analysis

Circular diamond saw performance is affected by a variety of factors. The principal factors requiring consideration when predicting cutting rates are the type and operating features of a diamond saw and the rock characteristics. The laboratory experimental tests are carried out on three groups of rocks (16 types) cut with the help of three types of diamond disk saws with different feed rates and cutting depths at constant peripheral velocity. The quantitative determinations of a wide range of textural, mechanical, and intact properties of rocks are also made. The relationship between the specific cutting energy SE _cut of the sawblade operating parameters and rock properties is established. Applying multivariable linear regression analysis, the predictive model of SE _cut is developed based on the rock property data. Models verified by statistical tests prove their practical validity. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 56–80, May–June, 2005.     

Geostatistical Analysis of Spatial Distribution of Salt Bed Thickness

The data on salt bed thickness distribution are processed using the semi-variogram analysis. Two- and three-dimensional maps of bed thickness distribution, as well as the error maps are presented.     

Revised stratigraphy of the Tertiary deposits of Istanbul and their engineering properties

For over 50 years, the Upper Oligocene–Upper Miocene sedimentary sequence in Istanbul has been considered to be formed of two distinct sequences separated by an unconformity. However, recent field observations and an analysis of numerous borehole data indicate the Gürp?nar, Çukurçe?me and Güngören Formations are in fact a single sequence of alternating clay–sand/sandstone beds/lenses, here named the Avc?lar Formation. The Bak?rköy Formation, which is typically composed of carbonate rocks, conformably overlies the Avc?lar Formation. The paper provides the geotechnical parameters of the units within the Avc?lar Formation which it is hoped will facilitate selecting suitable geotechnical and engineering geological parameters to represent the deposits and minimize errors in the interpretation/evaluation of in-situ conditions.     

Fast real-time caustics from height fields

Caustics are crucial in water rendering, yet they are often neglected in real-time applications due to the demanding computational requirements of the general-purpose caustics computation methods. In this paper we present a two-pass algorithm for caustics computation that is extremely fast and produces high-quality results. Our algorithm is targeted for commonly used height field representations of water and a planar caustic-receiving surface. The underlying theory of our approach is presented along with implementation details and pseudo codes.