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Effect of tempering upon the tensile properties of a nanostructured bainitic steel
The tensile properties of a nanostructured carbide-free bainitic steel formed at 200–250 °C are compared against those after tempering sufficiently to remove the retained austenite. Although significant ductility is observed following tempering, a comparison of tempered and untempered samples shows that it is in fact reduced when a comparison is made at identical strength. The shape of the stress–strain curves shows clear evidence that the capacity for work hardening is reduced with the loss of austenite. The nanostructure of the steel transformed at 250 °C is examined by transmission electron microscopy, to compare the as-transformed to the tempered structure. In this case after tempering at 500 °C the energy absorbed during the tensile test is lower, due to the lower strength. Reduction of strength is caused by the slight coarsening of the bainite plates, and lower dislocation density after tempering. Considering the formation of carbide particles in high strength steel, impressive ductility is exhibited even in the tempered condition.The authors would like to thank Professor A. L. Greer for the provision
of laboratory facilities at the University of Cambridge and also express their
gratitude to the Scholars Rescue Fund of International Institute of Education
in Washington DC, for supporting Hala Salman Hasan’s work in Cambridge.This is the accepted manuscript version. The final published version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S0921509314009642
Benign paroxysmal positional vertigo after radiologic scanning: a case series
<p>Abstract</p> <p>Introduction</p> <p>Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. It is frequently seen in elderly patients, and the course of the attack may easily mimic cerebrovascular disease. A BPPV attack after a radiologic examination has not been reported previously. We report the cases of two patients who had BPPV attacks after radiologic imaging.</p> <p>Case presentation</p> <p>The first patient with headache and tremor was admitted to the radiology department for cranial computed tomography (CT) imaging. During scanning, she was asked to lie in the supine position with no other head movements for approximately 10 minutes. After the cranial CT imaging, she stood up rapidly, and suddenly experienced a vertigo attack and nausea. The second patient was admitted to the radiology department for evaluation of his renal arteries. During the renal magnetic resonance angiography, he was in the supine position for 20 minutes and asked not to move. After the examination, he stood up rapidly with the help of the technician and suddenly experienced a vertigo attack with nausea and vomiting. The results of standard laboratory analyses and their neurologic examinations were within normal limits and Dix-Hallpike tests showed rotatory nystagmus in both cases. An Epley maneuver was performed to the patients. The results of a control Dix-Hallpike tests after 1 Epley maneuver were negative in both patients.</p> <p>Conclusion</p> <p>Radiologists and clinicians must keep in mind that after radiologic imaging in which the patient is still for some time in the supine position and then helped to stand up rapidly, a BPPV attack may occur.</p
Uji Kisaran Inang Potyvirus Penyebab Mosaik Nilam (Pogostemon Cablin (Blanco) Benth) Asal Sulawesi Tenggara
The objective of the research was to determine the host alternate of Potyvirus in Southeast Sulawesi using a host range technique. Observed variables were incubation period, disease incidence, and variation symptom. The research results showed that virus isolates could be mechanically transmitted to melon plant (Cucumismelo) but showing no external symptoms while on tomato (Solanum lycopersicum), long-beans (Vigna sinensis), tobacco (Nicotiana tabacum and Nicotiana benthamiana), swamp-land (Ipomoea reptana), red-amaranth (Alternantheraamoena), chili (Capsicum annum), and egg plant (Solanum melongena) so far the existence of the Potyvirus could not be detected after mechanically inoculated
Don’t FREAK out: a frequency-inspired approach to detecting backdoor poisoned samples in DNNs
In this paper we investigate the frequency sensitivity of Deep Neural Networks (DNNs) when presented with clean samples versus poisoned samples. Our analysis shows significant disparities in frequency sensitivity between these two types of samples. Building on these findings, we propose FREAK, a frequency-based poisoned sample detection algorithm that is simple yet effective. Our experimental results demonstrate the efficacy of FREAK not only against frequency backdoor attacks but also against some spatial attacks. Our work is just the first step in leveraging these insights. We believe that our analysis and proposed defense mechanism will provide a foundation for future research and development of backdoor defenses
UJI KISARAN INANG POTYVIRUS PENYEBAB MOSAIK NILAM (Pogostemon cablin (Blanco) Benth) ASAL SULAWESI TENGGARA
The objective of the research was to determine the host alternate of Potyvirus in Southeast Sulawesi using a host range technique. Observed variables were incubation period, disease incidence, and variation symptom. The research results showed that virus isolates could be mechanically transmitted to melon plant (Cucumismelo) but showing no external symptoms while on tomato (Solanum lycopersicum), long-beans (Vigna sinensis), tobacco (Nicotiana tabacum and Nicotiana benthamiana), swamp-land (Ipomoea reptana), red-amaranth (Alternantheraamoena), chili (Capsicum annum), and egg plant (Solanum melongena) so far the existence of the Potyvirus could not be detected after mechanically inoculated
Dhaka city water logging hazards: area identification and vulnerability assessment through GIS-remote sensing techniques
Water logging is one of the most detrimental phenomena continuing to burden Dhaka dwellers. This study aims to spatio-temporarily identify the water logging hazard zones within Dhaka Metropolitan area and assess the extent of their water logging susceptibility based on informal settlements, built-up areas, and demographical characteristics. The study utilizes integrated geographic information system (GIS)-remote sensing (RS) methods, using the Normalized Difference Vegetation Water and Moisture Index, distance buffer zone from drainage streams, and built-up distributions to identify waterlogged zones with a temporal extent, incorporating social and infrastructural attributes to evaluate water logging effects. These indicators were integrated into an overlay GIS method to measure the vulnerability level across Dhaka city areas. The findings reveal that south and south-western parts of Dhaka were more susceptible to water logging hazards. Almost 35% of Dhaka belongs to the high/very highly vulnerable zone. Greater number of slum households were found within high to very high water logging vulnerable zones and approximately 70% of them are poorly structured. The built-up areas were observed to be increased toward the northern part of Dhaka and were exposed to severe water logging issues. The overall findings reveal the spatio-temporal distribution of the water logging vulnerabilities across the city as well as its impact on the social indicators. An integrated approach is necessary for future development plans to mitigate the risk of water logging
Metode Infrared Thermography (IRT) untuk deteksi cepat lubang aktif tikus sawah
Tikus sawah (Rattus-rattus argentiventer) dapat menyebabkan kerusakan yang parah pada tanaman padi sawah. Pengendalian dengan fumigasi (pengasapan) berbahan aktif sulfur dapat membunuh tikus dalam lubang pematang. Fumigasi akan efektif bila lubang aktif tikus diketahui, namun mengenali lubang aktif tikus tidaklah mudah. Tujuan penelitian ini adalah mengevaluasi potensi metode Infrared Thermography (IRT) dalam mendeteksi lubang aktif tikus sawah melalui visualisasi citra termal. Beberapa lubang tikus yang ditemukan di areal persawahan milik petani di Desa Lebo Jaya, Kecamatan Konda, Kabupaten Konawe Selatan, Provinsi Sulawesi Tenggara direkam citra termalnya menggunakan FLIR C2 Compact Thermal Imager. Selanjutnya, citra termal dan RGB (red green blue) diolah menggunakan aplikasi FLIR Tools versi 6.4.18039.1003 (FLIR® Systems, USA) dan dilanjutkan dengan analisis suhu rata-rata lubang tikus menggunakan Microsoft Excel. Hasil pengolahan citra termal menunjukkan bahwa area tanah galian lubang tikus yaitu area sisi dalam lubang berwarna lebih gelap yang menandakan bahwa suhu tanah di area tersebut lebih rendah sampai berkisar pada suhu 28 °C, sebaliknya area sisi luar lubang berwarna lebih terang yang menandakan bahwa suhu tanah yang lebih tinggi sampai berkisar pada suhu 32 °C. Metode IRT ini sangat potensial untuk dimanfaatkan sebagai metode deteksi cepat lubang aktif tikus sawah. Implementasinya bersama teknologi drone (UAV) akan mengefisienkan waktu petani saat menandai lubang aktif tikus sawah pada areal persawahan yang luas. Selain itu, pengendalian tikus dengan teknik fumigasi juga akan menjadi lebih efektif dan ekonomis
Rapid adaptation in online continual learning: are we evaluating it right?
We revisit the common practice of evaluating adaptation of Online Continual Learning (OCL) algorithms through the metric of online accuracy, which measures the accuracy of the model on the immediate next few samples. However, we show that this metric is unreliable, as even vacuous blind classifiers, which do not use input images for prediction, can achieve unrealistically high online accuracy by exploiting spurious label correlations in the data stream. Our study reveals that existing OCL algorithms can also achieve high online accuracy, but perform poorly in retaining useful information, suggesting that they unintentionally learn spurious label correlations. To address this issue, we propose a novel metric for measuring adaptation based on the accuracy on the near-future samples, where spurious correlations are removed. We benchmark existing OCL approaches using our proposed metric on large-scale datasets under various computational budgets and find that better generalization can be achieved by retaining and reusing past seen information. We believe that our proposed metric can aid in the development of truly adaptive OCL methods. We provide code to reproduce our results at https://github.com/drimpossible/EvalOCL
DETEKSI POTYVIRUS PADA NILAM (Pogostemon Cablin (BLANCO) BENTH) DENGAN TEKNIK ELISA DI SULAWESI TENGGARA
Mosaic symptoms were observed on Patchouli (Pogostemon cablin) around North Kolaka and Kolaka, Southeast Sulawesi during surveys in early 2012. Indirect-ELISA based detection was conducted using symptomatic leaf samples. The objective of the research was to determine disease incidence of Potyvirus in several farms of Patchouli plant in Southeast Sulawesi. The results showed that Patchouli plant (Pogostemon cablin) was found to be infected with Potyvirus disease showing mosaic symptoms and malformation on the leaf samples i.e. in Amotowo and Boro-Boro Villages of subdistrict Boro-Boro, and Landabaro Village, Mowila subdistrict of South Konawe regency; Asinua Village of subdistrict Unaaha, Lambuya district of subdistrict Lambuya, and Bungguosu district, Konawe subdistrict of Konawe regency; and Anduonohu district, Poasia subdistrict of Kendari regency. This is the first report on Potyvirus infection on patchouli in Southeast Sulawesi. Keywords: Inderect-ELISA, mosaic, Potyvirus, Pogostemon cabli
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