489 research outputs found
Diurnal changes of earthquake activity and geomagnetic Sq-variations
Statistic analyses demonstrate that the probability of earthquake occurrence in many earthquake regions strongly depends on the time of day, that is on Local Time (e.g. Conrad, 1909, 1932; Shimshoni, 1971; Duma, 1997; Duma and Vilardo, 1998). This also applies to strong earthquake activity. Moreover, recent observations reveal an involvement of the regular diurnal variations of the Earth’s magnetic field, commonly known as Sq-variations, in this geodynamic process of changing earthquake activity with the time of day (Duma, 1996, 1999). In the article it is attempted to quantify the forces which result from the interaction between the induced Sq-variation currents in the Earth’s lithosphere and the regional Earth’s magnetic field, in order to assess the influence on the tectonic stress field and on seismic activity. A reliable model is obtained, which indicates a high energy involved in this process. The effect of Sq-induction is compared with the results of the large scale electromagnetic experiment "Khibiny" (Velikhov, 1989), where a giant artificial current loop was activated in the Barents Sea
Analisis kinerja turbin air arus bawah bentuk sudu bengkok dengan variasi material
A water turbine is a device used to convert the potential energy of water into mechanical energy. This mechanical energy is then converted into electrical energy by a generator. This test was carried out experimentally using a crooked blade type with six blades and the type of water turbine used was undershoot. Various type of blade materials are plastic, aluminum, and iron. As well as varying the opening of fluid flow, namely the valve opening of 25%, 50%, 75%, and 100%.The results obtained indicate that variations in turbine blade material have effect on turbine power and turbine efficiency The highest turbine power and efficiency was obtained at 100% valve opening with load of 0.7 kg on plastic, iron and aluminum material. The highest turbine power is 1.1608 watt for the plastic blade, for aluminum blade is 1.2219 watt, for iron blade is 1.0997 watt. The highest efficiency obtained for plastic blades is 50.1360 %, for aluminum blades is 52.7748%, for iron blades is 47.4973 % A water turbine is a device used to convert the potential energy of water into mechanical energy. This mechanical energy is then converted into electrical energy by a generator. This test was carried out experimentally using a crooked blade type with six blades and the type of water turbine used was undershoot. Various types of blade materials are plastic, aluminium, and iron. As well as varying the opening of fluid flow, namely the valve opening of 25%, 50%, 75%, and 100%. The results obtained indicate that variations in turbine blade material have an effect on turbine power and turbine efficiency The highest turbine power and efficiency was obtained at 100% valve opening with a load of 0.7 kg on plastic, iron and aluminium material. The highest turbine power is 1.16 watts for the plastic blade, the aluminium blade is 1.22 watts, and for the iron, the blade is 1.1 watts. The highest efficiency obtained for plastic blades is 50.14 % for experiment and theoretical is 5.67%, aluminium blades are 52.77% for experiment and 54.41% for theoretical, iron blades are 47.5% for experiment and 48.97% for theoretical
Should I stay or should I go? How local-global implicit temporal expectancy shapes proactive motor control: An hdEEG study
In this study, we investigated the effect of global temporal prediction on the brain capability to implicitly adjust proactive motor control. We used the Dynamic Temporal Prediction (DTP), in which local and global predictions of an imperative stimulus were manipulated by using different stimulus-onset asynchronies (SOAs), presented with several distribution probabilities. At a behavioural level, the results show a performance adjustment (reaction time decrease) depending on the implicit use of global prediction. At a neurophysiological level, three separate computational steps underlying motor control were investigated. First, the expectancy implementation was associated with global probability-dependent contingent negative variation (CNV) modulation supported by the recruitment of a frontoparietal network involving the anterior cingulate, the left intraparietal sulcus, the occipital, and the premotor areas. Second, the response implementation was modulated by the global prediction fostering stimulus processing (P3 increase) at the motor response level, as suggested by both oscillatory (beta desynchronization), as well as source analysis (frontal cortical network). Third, the expectancy violation lead to a negativity increase (omission-detection potential) time locked to the global rule violation and additionally, to delta and theta power increase interpreted as inhibitory control and rule violation detection, respectively. The expectancy violation further engaged a left lateralized network including the temporal parietal junction (TPJ) and the motor cortex, suggesting involvement of attentional reorienting and a motor adjustment. Finally, these findings provide new insights on the neurocognitive mechanisms underlying proactive motor control, suggesting an overlapping between implicit and explicit processes
SISTEM PENGHITUNG OTOMATIS UNTUK PINTU MASUK GEDUNG IBADAH
Dengan situasi Covid-19 saat ini, pemerintah terus menghimbau untuk menerapkan pola hidup sehat, terutama mencuci tangan dan memakai masker. Selain mencuci tangan dan memakai masker, pemerintah terus menghimbau masyarakat untuk menghindari tempat – tempat keramaian. Hal ini juga dilakukan oleh jemaat di Gereja Kaisarea BTN Kolhua, Kota Kupang, Nusa Tenggara Timur. Namun permasalahan yang sering terjadi pada tempat ibadah Gereja Kaisarea yaitu masih menghitung jumlah jemaah yang akan masuk ruang pelayanan secara manual. Hal ini dinilai kurang efisien karena akan terjadi penumpukan pada pintu masuk jika sejumlah jamaah masuk ruang ibadah secara bersamaan atau berdesak - desakan. Selain itu, jika menggunakan perhitungan jumlah Jemaah secara manual dengan hand tally counter didapatkan tingkat kesalahan penghitungan masih cukup tinggi jika yang bertugas menghitung jumlah jemaah tidak fokus pada proses penghitungan. Oleh karena itu, pada penelitian ini tim peneliti akan merancang sistem penghitungan jumlah jemaah Gereja Kaisarea BTN Kolhua secara otomatis menggunakan Arduino dan Sensor Proximity Infrared. Sensor akan ditempatkan pada pintu masuk untuk mengetahui jumlah Jemaah yang hadir didalam ruang ibadah deng cara menghitung selisih antara Jemaah yang masuk maupun keluar.
Dari hasil perhitungan, diketahui tinggkat akurasi tertinggi dihasilkan dari sistem penghitung otomatis yaitu sebesar 99,8 %. Sedangkan menggunakan sistem manual, memiliki tingkat akurasi sebesar 99,0 %. Dengan menggunakan sistem perhitungan otomatis ini, sangat membantu para petugas yang menghitung jumlah Jemaah karena proses perhitungan tidak dilakukan secara manual yang memakakn waktu dan tenaga 
Misoprostol alone for the termination of pregnancy
The administration of mifepristone, a powerful antiprogestin, coupled with a prostaglandin, is a highly effective medical method of terminating pregnancy. Of the most widely used prostaglandins, namely gemeprost and misoprostol, the latter shows the greater promise for developing countries, since it can be administered orally and is inexpensive, stable at ambient temperatures and widely available.
South African Family Practice Vol. 49 (3) 2007: pp. 1
A combination of imaging techniques for dental medicine: from X-rays radiography and 3D CBCT to OCT
The assessment of dental issues is done nowadays both clinically and radiologically. The latter includes radiographs that are based on X-ray radiation, i.e. intraoral radiography, panoramic radiography, and three-dimensional (3D) cone beam computed tomography (CBCT). In several cases, radiographs have limitations, as they do not reveal dental issues such as small cavities, enamel cracks, or tooth erosion. These aspects can be visible with another medical imaging technique, Optical Coherence Tomography (OCT). The aim of this study is to present a few results obtained with an in-house developed swept-source OCT (SS-OCT) system on several dental issues that cannot be visible on radiographs. These results prove that OCT can be utilized in dentistry, with advantages such as radiation free technique and superior resolution. This study presents both radiography and OCT images for different dental issues which include small cavities, metal crowns cracks, or crowns manufactured with different materials (i.e., zirconia, ceramics, or composite). Firstly, samples have been analyzed radiologically and some abnormalities could be detected, but they could be correctly assessed. Secondly, these abnormalities have been analyzed with the SS-OCT system and finally all images and collected data from both medical imaging techniques have been compared. One of the conclusions is that OCT is more appropriate than radiography for several dental issues such as those presented in this study. These two medical imaging techniques can therefore be complementary in dental medicine
Features of arrival time and angle-of-incidence distributions of EAS muons
Charakteristika und Abhängigkeiten von Ankunftszeit- und Einfallswinkelverteilungen von Myonen ausgedehnter Luftschauer
Verschiedene charakteristische Eigenschaften und Korrelationen von Ankunftszeit- und Einfallswinkelverteilungen von Myonen ausgedehnter Luftschauer (EAS) werden untersucht auf der Grundlage von Monte-Carlo Simulationen der EAS Entwicklung mit Hilfe des Simulations-Codes CORSIKA. Die Ankunftszeitverteilungen und Winkel-verteilungen werden charakterisiert durch die Ankunftszeit bzw. Einfallswinkel des ersten Myons, durch Mittelwerte und Median-Werte der Verteilungen in den einzelnen Schauern.
Spezielles Augenmerk wird gerichtet auf Vielfach-Korrelationen bei gleichzeitigen Beobachtungen in verschiedenen Abständen vom Schauer-Zentrum. Es wird gezeigt, daß ein solcher Beobachtungsmode zusätzliche Informationen zur Verbesserung der Unterscheidung der Art der Primärteilchen liefert
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