With the argument that two-electrode DBD-like systems are much more operational than single-electrode systems in biomedical applications, targets sensitive to temperature and electric shock, the effects of parameters associated with the geometry of the grounded electrode such as its shape, size, and position it at the output of the atmospheric pressure RF plasma jet in two-electrode systems is investigated. By varying the position of the typical narrow ring grounded electrode on the dielectric tube toward the powered electrode, the ratio of the axial to radial electric field components depend on the externally applied potential to the plasma has been investigated and shown that the axial component of the electric field is maximized at certain position(s) of the grounded electrode. The analysis of the data indicates that there is an inverse relationship between the magnitude of the axial electric field in the plasma channel and the discharge ignition voltage, and a direct relationship with the plasma jet length. It is known that by increasing the width of the ground electrode until the full covering of dielectric, the jet length increases from the dielectric output to the neighborhood near the needle electrode, and reduces the discharge ignition threshold and consequently power consumption of the jet, but increasing its width to greater than the above values does not have a significant effect on jet output. It has also been shown that by tapering the dielectric end and fully covering it with its conical-shaped electrode, the output jet length increases and decreases its width.

In this research, ultraviolet (UV) photodetectors based on aligned ZnO nanorods thin films with controllable responsivity were fabricated. Aligned nanorods were grown on seeded glass substrates by the chemical bath method. Then, they were characterized using a Scanning Electron Microscope (SEM), X-ray diffraction (XRD), photoluminescence (PL), and Energy Dispersive X-ray Analysis (EDAX). The effect of perimeter and area variation of interdigitated electrodes on the responsivity of UV ZnO nanorods-based photodetector was investigated. With a decreasing electrode perimeter and maintaining the same area, the responsivity decreases. By keeping the perimeter constant at the maximum value, it is observed that the response of the photodetector is increased with increasing the gap between the fingers of the electrode so that the gap of 160 µm reaches the maximum as high as 105 AW-1 at 2 V bias voltage. The dominant mechanism for change of responsivity with electrode geometry is variation in the area of depletion regions resulting from Schottky barriers between ZnO and Au and the formed barriers between ZnO nanorods due to adsorption and desorption of oxygen species. This research demonstrates a simple way of optimizing photodetector devices' responsivity for practical applications.

A Study of Geometry in Islamic Architecture by Professor Golroo Najibaaghlou is a valuable work in the field of Islamic architecture. This book has a detailed preface, a brief introduction, and five main sections. As it is known from the introduction of the book, this book was originally written for a non-Iranian audience. The first purpose of writing this book is to try to moderate public belief about geometry and the stages of compilation and discussion in Islamic architecture. Another purpose is to correct the negative view of the geometric documentation of Islamic architecture in the West, because such a view has created a kind of reluctance to equate the works of Islamic architecture with the great works of classical Western architecture. In addition, Najibaaghlou wants to reject and respond to Western criticism that reduces Islamic architecture to the level of an unedited work. In the final chapter of the book, Najibaaghlou looks at the compiled documents of Islamic architecture from a Western perspective and highlights some of the missed points of geometric sciences, including clarifying conceptualization, recording, and transferring architectural design in the Islamic world.

The main purpose of the article, as the topic itself shows, is defining an eternal geometry(as a basic foundation and unavoidable structure)for the Islamic architecture. Therefore, as an abstract of this article, (giving a short but conclusive definition of the main subject),and in order to avoid from some possible misunderstandings in the mentioned subjects and meanings in the article, the following points seems to be useful:A. The referring meaning of the word "Geometry" (or its Arabic synonym "Hindiseh") by the author in this (article) is completely different from the common meaning of it in architecture (or the Euclidian Geometry) and its closed and limitful field of rules of some mathematical meanings and physical shapes and forms. But by the phrase "Hindiseh Jaavidan" or "Eternal Geometry" the author means the Unique, Wholistic and Comprehensive Truth, which according to the Quranic literature, is known by some Arabic terms such as "qadr", "taqdeer" and "muqaddir", "muqaddar", "qadeer", and so on. The meaning which points to the comprehensive and wholistic system of rules governing all various systems of measurement essential for the whole universe and its every individual parts's or thing's coming into existence (in their both physical being and meaningful identity).B. According to the above mentioned description, the referring meaning of the phrase "Natural Geometry" (or "Hindisi-yi Tabee 'at" or "Taqdeer") by the author in this article can be imagined as a symbolic light through which everything in the universe become visible, readable and understandable for every other thing in the whole cosmos of varieties and multiplicities (in both qualitative and quantitative groups of limits and measures). The limits and measures without which everything's essential mutual relation and harmonic suitable cooperative sharing life with every other thing in the world seems to become impossible.C. Then, in a similar symbolic structure, the other important meaning of "Geometry" or "Hindisih" to which the author is going to point to is "The Essential Geometry" or "Hindisik-yt Dhaatee". According to the Holy Quran, for every possible matter of being in the physical world, there is a limitless, unchangeable, eternal specific and determined Truth in The Presence of God which, as same as all other Truthful Meanings in such a Sacred Presence is free from all limits essential for the material world such as: matter, physical shape and form, length, width, thickness, color and other similar limits.D. And at last, the author's purposed meaning of the subject of "Islamic Architecture" in this article, is an orderly and unitary structure which in its both whole and parts, and in its both physical structure and meaningful identity obey the One Divine System of Rules named Islam. And, at last, by the word of "Islam" means the universal governing order of both physical and spiritual worlds.

Nowadays, there is a desire in various industries, especially in the automotive industry, to join dissimilar sheet metals in order to reduce weight. Resistance spot welding is often applied to join body parts and its strength and dimensions of the weld are important. In this research, the influence of the electrode geometry with a diameter of 20 and 50 mm on the indentation depth of the resistance welding spot in the joining of sheet steel and the magnesium alloy AZ31 was investigated. A tensile shear test was carried out to evaluate the strength of the weld. The results showed that the strength of the joint was 5000 N and the 50% reduction in indentation depth by the electrode with a geometry diameter of 50 mm with an average indentation depth of 0. 6 mm on the magnesium side. The structure of the weld in this joint had three Braze, solid solution, and solder regions. Moreover, dendritic coaxial grains in the center and coaxial and columnar grains at the periphery of the spot weld were observed.

In this paper, the logical development of Euclidean geometry as presented in Euclid’s Elements, has been studied. Pointing out some gaps in the Euclid arguments, the need for modern axiomatic systems has been explored.

The geometry of imagination and thought are important tools to acquire knowledge. Human beings have always deployed these two significant tools to get an understanding of the macrocosm and microcosm. These two factors have been incorporated and well utilized to achieve a proper appreciation of these profound entities. This essay engages the strong links between knowledge and art by nature and struchire. There are samples of Hafiz poetry to the demonstrates the marriage of thoughts and the geometr-v of imagination as well to depict the mathematical relationship between their thought patterns.

In the present study, in order to fabricate AC electroosmotic micropumps, the improvement of geometrical parameters of the 3D electrode, such as width, height, and location of 3D steps on the base electrodes in one pair, the base electrodes size (symmetric or asymmetric), electrodes gap, and also electrical characteristics including voltage and frequency have been investigated. Also, the fluid flow (KCl) in the channel was analyzed. The governing equations of fluid flow and electrical domain have been solved using the finite element method to investigate the effect of electrode geometry on slip velocity, which affects the fluid flow. In order to validate our numerical simulation, this chip is fabricated by photolithography method such as deposition of platinum electrodes, creating 3D steps on the base electrodes using a polymer, and fabrication of a microchannel. Finally, Our results indicate that an optimal design results in a pump with the width (50 µm) and steps height (5 µm) of each electrode and their displacement (30 µm) are capable of generating a high velocity, flow rate, and pressure around 1.77 mm/s, 14.9 ml/min and 74.6 Pa, respectively at a given voltage (2.5 V) and frequency (1 kHz), which qualitatively matches the trend observed in the experiment. This design provides an improvement in electroosmotic pumping.