This paper is an analysis of determination possibility of the optical absorption coefficient spectra of thin semiconductor layers from their normalized photoacoustic amplitude spectra. Influence of multiple reflections of light in thin layers on their photoacoustic and optical absorption coefficient spectra is presented and discussed in detail. Practical formulae for the optical absorption coefficient spectrum as a function of the normalized photoacoustic amplitude spectrum are derived and presented. Next, they were applied for computations of the optical absorption coefficient spectra of thin In₂S₃ thin layers deposited on a glass substrate. This method was experimentally verified with the optical transmission method.

In this new era, we are facing a major problem regarding wastewater in the environment, which has an adverse effect on human life. Wastewater from tanning industries is one of the major contributors to the pollution in aquatic systems. Tannery industries have always contributed to the world’s economy and trade despite facing criticism due to environmental pollution. Tanning effluent consists of organic, inorganic (chromium, nitrogenous compounds), and a large amount of solid content like TDS, TSS, TVS. To overcome these significant challenges, there have been few advancements related to tannery wastewater treatment. This article aims to provide a brief review on electrocaogulation based treatment technologies for eliminating the impurities from tannery wastewater. This review consists of the background with characteristics of tannery wastewater, the alternatives for treating the tannery effluent over the years along. A detailed description of the advanced technologies based on electrocoagulations is implemented to overcome the drawbacks of the existing methods.

A triple-band microstrip patch antenna is presented in this article with detail investigation of its working mechanism and performance characteristics. The antenna consists of a rectangular slot on the patch to achieve multiband operation. Three distinct frequencies of 2.4 GHz, 5.5 GHz and 7.5 GHz are achieved with return losses of 27 dB, 29 dB and 29 dB respectively. The Impedance Bandwidths are 70 MHz (2.52 GHz-2.44 GHz) at 2.4 GHz, 220 MHz (5.65 GHz-5.43 GHz) at 5.5 GHz and 250 MHz (7.57 GHz-7.32 GHz) at 7.5 GHz, which satisfy the requirements of Wi-Fi, Wi-MAX and satellite communications bands. The fabricated prototype of the antenna has total dimension of 53×53×1.6 mm3 over FR4 substrate. The antenna is simple and has sensible radiation characteristics with considerable gain. This work also focuses on developing a Link Budget model for its application in satellite communication. Most notably, it examines overall system efficiency and optimum path loss, distance analysis, system noise temperature, signal to noise power ratio, the size of antenna and the overall customer satisfactions. The highest gain of the antenna is achieved as 3.5 dB in the band (5.65 GHz-5.43 GHz), while the highest directivity and bandwidth are found as 8.7 dBi and 250 MHz respectively in the higher operating band. The affordable agreement between the simulated and measuring outcomes justifies that the antenna is often applicable for Wi-Fi (2.4 GHz), Wi-MAX (5.25 – 5.85 GHz) and satellite (7.24 – 7.57 GHz) communications.

Ultrasonic assisted active-passive filling friction stir repairing (A-PFFSR) was proposed to repair volume defects in the metallic parts. Sound joints without interfacial defects could be achieved. Firstly, the ultrasonic was beneficial to improving material flow and atom diffusion, and then eliminated kissing bond defects compared to conventional A-PFFSR joints. Secondly, the equiaxed grains were refined by ultrasonic vibration. Lastly, the repairing passes were reduced due to the ultrasonic, which decreased softening degree of the repaired joints. The maximum tensile strength of 150 MPa was achieved. Therefore, this strategy to repair the volume defects is feasibility and potential in the remanufacturing fields of aerospace and transportation.

The nonlinear mathematical model of behavior of controllable viscosity fluid (CVF) under applied external field is presented. A large family of these fluids is commonly used to control responding forces of dampers in vibration control applications. The responding force of a damper with CVF has two components. The first one - uncontrollable - is proportional to the viscosity of a base fluid and velocity of its motion, the second one, which is controllable, depends on the strength of the applied external field. Both are involved in the process of dissipation of unwanted energy from the vibrating systems. An equivalent damping factor based on the principle of energy dissipated during one cycle of damper work under a constant strength external field was calculated. When mass or stiffness is variable the equivalent damping factor can be set accordingly by adjusting the strength of external field to have vibrating damped system purposely/continuously working in the critical or other chosen state. This paper also presents cases of applying periodically changing strengths of an external field synchronized with cycles of periodical motion of the vibrating system to continuously control the damping force within each cycle.

The propagation of EEG activity during the Continuous Attention Test (CAT) was determined by means of Short-time Directed Transfer Function (SDTF). SDTF supplied the information on the direction, spectral content and time evolution of the propagating EEG activity. The differences in propagation for target and non-target conditions were found mainly in the frontal structures of the brain.

The S. Torkar book that is discussed and reviewed in this article deals with historical anthroponymy and toponymy of eastern Tolminsko region in north-western Slovenia.
Written with the diligence and meticulousness of a Benedictine monk, the monograph features a wide‑ranging array of material, multiple sources and extensive subject literature, state‑of‑the‑art onomastic and general linguistic methodology, references to general Slavic language and linguistic, use of historical and ethnographic knowledge, and precision shown by the use of, among others, the statistical method I believe that this book is an eminent piece of scholarly literature.