Existentialism and epistemology.

Comments on B. Vandenberg's (see record 1992-12211-001) article on epistemology and an existential consideration of development, taking exception with both his definition of existentialism and his characterization of Piaget's work. Existentialism, it is argued, is not an alternative to epistemology, but a particular style of responding to philosophic questions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessment of the effectiveness of the educational environment supported by computer aided presentations at primary school level

The objective of this study is to assess the effectiveness of the educational environment supported by computer aided presentations at primary school. The effectiveness of the environment has been evaluated in terms of students’ learning and remembering what they have learnt. In the study, we have compared experimental group and control group in terms of learning and recalling what has been learned regarding the effect which computer aided learning environment imposes. Data have been collected through the control grouped pretest–final test model. During the experiment, we have prepared an achievement test, which explains behaviors the students should acquire. According to the findings obtained, a computer aided educational environment has been observed to be more effective than that of conventional education in terms of learning. However, in terms of the permanence of what has been learned, no meaningful difference between the educational environment supported by computer aided presentations and that of conventional education has come out. According to the results of the follow-up tests performed, even though students in the test group have forgotten more of what they have learnt, it has been concluded that students in both groups have forgotten on the same level. Consequently, it has been observed that though the educational environment supported by computer aided presentations has positive contributions to learning activity, it does not have effects on the permanence of what has been learnt.     

Experimental study of a micro-scale sloped solar chimney power plant

Journal of Mechanical Science and Technology - Solar chimney power plants (SCPP) are structures that have the potential to generate a significant amount of electrical energy without harming the...     

Performance evaluation of a submerged membrane bioreactor for the treatment of brackish oil and natural gas field produced water

Produced water, which is co-produced during oil and gas manufacturing, represents one of the largest sources of oily wastewaters. Therefore, treatment of this produced water may improve the economic viability and lead to a new source of water for beneficial use. In this study a submerged hollow fiber membrane bioreactor (MBR) has been studied experimentally for the treatment of brackish oil and natural gas field produced water. This type of wastewater is also characterized with relatively moderate to high amount of salt, oil and total petroleum hydrocarbons (TPH). However, the bacteria which are growing in conventional activated sludge and MBR cannot survive at these strict conditions, therefore acclimation of the bacteria is of vital importance. The performance of the biological system, membrane permeability, the rate and extent of TPH biodegradability have been investigated under different sludge age and F/M ratios. The results obtained by gas chromatography analyses showed that the MBR system could be very effective in the removal of TPH from produced water and a significant improvement in the effluent quality was achieved.     

Effects of liquid smoke on quality characteristics of Turkish standard smoked beef tongue

The purpose of this research was to determine some quality characteristics of beef tongues processed with liquid and vaporous (traditional) smoke. The tongues were divided into two groups; traditional (vaporous) smoking and liquid smoke application groups, and the processed tongues were vacuum packaged and monitored for quality during 30 days of storage at 4±1?°C. All the smoked tongue samples were subjected to chemical, microbiological and organoleptic analysis at 0, 5, 10, 15 and 30 days of storage. The results indicated that despite some favorable results attributed to traditional smoking, liquid smoke application of beef tongue is also possible without causing any major acceptability problems in terms of quality.     

Design of a 3D aligned myocardial tissue construct from biodegradable polyesters

The heart does not regenerate new functional tissue when myocardium dies following coronary artery occlusion, or if it is defective. Ventricular restoration involves excising the infarct and replacing it with a cardiac patch to restore the heart to a more healthy condition. The goal of this study was to design and develop a clinically applicable myocardial patch to replace myocardial infarcts and improve long-term heart function. A basic design composed of 3D microfibrous mats that house mesenchymal stem cells (MSCs) was developed from human umbilical cord matrix (Wharton’s Jelly) cells aligned in parallel to each other mimicking the native myocardium. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(L-D,L-lactic acid) (P(L-D,L)LA) and poly(glycerol sebacate) (PGS) were blended and electrospun into aligned fiber mats with fiber diameter ranging between 1.10 and 1.25 μm. The micron-sized parallel fibers of the polymer blend were effective in cell alignment and cells have penetrated deep within the mat through the fiber interstices, occupying the whole structure; 8–9 cell layers were obtained. Biodegradable macroporous tubings were introduced to serve as nutrient delivery route. It was possible to create a thick myocardial patch with structure similar to the native tissue and with a capability to grow.     

Special issue on microscopic image processing

The applications of biometric technology for automated personal identification become ubiquitous. Iris recognition is well known for high accuracy and reliability among the biometric traits. This paper presents an efficient noise-removing approach for non-cooperative iris recognition systems. Proposed method removed the noise factors including eyelids, eyelashes, reflections, out of framework, pupil and sclera. The novelty is to detect eyelashes and reflections through finding appropriate thresholds using a procedure called statistical decision making. The eyelids are detected using parabolic Hough transform in normalized iris image to increase computational speed. In addition, a coarse-to-fine strategy for accurate and fast iris localization is proposed. The Gabor-wavelet and a novel encoding strategy proposed in our previous work are also used here to generate the iris codes. We elaborate the principle of mask code generation to assign noisy bits in an iris code to exclude them in matching step. Experimental results on CASIA-IrisV3-Interval database show superiority of the proposed scheme among other state-of-the-art methods available in the literature.     

The effect of Sn concentration on some physical properties of zinc oxide films prepared by ultrasonic spray pyrolysis

The effect of Sn concentration on zinc oxide (ZnO) film properties has been investigated by depositing films with various Sn concentrations in the solution (Sn/Sn + Zn ratio from 0 to 50 at%) at a substrate temperature of 350°C by ultrasonic spray pyrolysis (USP) technique. The deposited films were characterized for their electrical, structural, morphological and elemental properties using current-voltage and conductivity-temperature measurements, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. Electrical investigations showed that the resistivity of ZnO films decreases for lower Sn concentration (at 10%) and then increases for higher Sn concentration (at 30–50%). Also, depending on the increasing Sn concentration, energies of donor-like traps for ZnO films decreased and activation energy of donors for ZnO films increased. The XRD patterns showed that the as-deposited films have polycrystalline structure and the crystalline nature of the films was deteriorated with increasing Sn concentration and a shift to amorphous structure was seen. The effect of Sn concentration was to increase the surface roughening and change considerably the morphologies of ZnO films. The most homogenous surface was seen in ZnO films. EDS results showed that all elements in the starting solutions were in the solid films and Zn element is more dominant than Sn on the surfaces. After all investigations, it was determined that Sn incorporation dramatically modifies the properties of ZnO films. ZnO and ZnO:Sn (10 at%) films have a low resistivity and high transparency in the visible range and may be used as window material and antireflecting coating in solar cells while the other films may be used in gas sensors where high conductivity is unnecessary.     

Estimation of limit angle using laminated displacement discontinuity analysis in the Soma coal field, Western Turkey

Determination of the limit angle at the Manisa-Soma-Eynez coal field, a major coal production area in Turkey, is difficult because of the presence of a landslide caused by the waste from a neighboring open-pit site being dumped over the underground mine at the Soma-Eynez basin. In fact, it is not possible to determine the effect of extraction on the surface from field studies. Thus, in order to determine the limit angle, in-situ subsidence measurements, geophysical measurements, rock-based tests in the laboratory and the data obtained from a physical model have supported numerical modeling studies. The software, LAMODEL, used for the numerical modeling was developed by National Institute for Occupational Safety and Health (NIOSH), and is based on the Boundary Element Method. The results obtained from modeling have been found to be compatible with other studies and as a result the limit angle has been determined.     

Growth and Characterization of Zn-Incorporated Copper Oxide Films

In this work, undoped and Zn-doped copper oxide films were deposited on glass substrates at a substrate temperature of 250 ± 5°C by using an ultrasonic spray pyrolysis technique. Electrical, optical, and structural properties of the films were investigated, and the effect of Zn incorporation on these properties are presented. The variations of electrical conductivities and electrical conduction mechanisms of all films were investigated in the dark and in the light. Optical properties of the produced films were analyzed by transmission, linear absorption coefficient, and reflection spectra. The band gaps of the films were determined by an optical method. The film structures were studied by x-ray diffraction. To obtain information about structural properties in detail, the grain size (D), dislocation density (δ), and lattice parameters for preferential orientations were calculated. The elemental analyses were performed using energy-dispersive x-ray spectroscopy. It was concluded that Zn has a strong effect, especially on the electrical and structural properties, and the undoped and Zn-doped copper oxide (at 3%) films may be used as absorbing layers in solar cells due to their low resistivities and suitable linear absorption coefficient values.