Effects Of Backfill Soil On Pipeline’s Mechanical Response Subjected To Perilous Rock Impact

Perilous rock impact is one of the most serious geological disasters that threats to buried pipeline security. Mechanical behavior of buried pipeline in rock stratum impacted by perilous rock was simulated in this paper. And effects of impact velocity and backfill soil parameters on stress and strain of pipeline were discussed. The resluts show that cross section shape of pipeline is oval when impact velocity is small. Impact dent appears on pipeline with the increasing of impact velocity, buckling is more serious and plastic stain increases. Under low velocity impact, stress and plastic strain decrease with the increasing of soil\u27s elastic modulus. Plastic strain increases first and then decreases with the increasing of soil\u27s Poisson\u27s ratio. With the increasing of soil\u27s cohesion, plastic strain increases, but stress first increases and then decreases. Under high velocity impact, deformation and plastic strain increase with the decreasing of elastic modulus and Poisson\u27s ratio. But cohesion has a small effect on buckling behavior of pipeline

Back-stepping variable structure controller design for off-road intelligent vehicle

In this paper, off-road path recognition and navigation control method are studied to realize intelligent vehicle autonomous driving in unstructured environment. Firstly, the traversable path is achieved by vision and laser sensors. The vehicle steering and driving coupled dynamic model is established. Secondly, a coordinated controller for steering and driving is proposed via the back-stepping variable structure control method, which can be used to deal with the unmatched uncertainties of the control system model. To reduce the chattering phenomenon caused by variable structure, the boundary layer approach is introduced. The results of simulation and off-road experiment show the effectiveness and robustness of the proposed controller

Theoretical and Experimental Study on the Speed-up of Freight Train with Mixed Marshaling of Light and Heavy Vehicle

To study the influence of the speed-up of a freight train with mixed marshaling of light and heavy vehicles on the dynamic behavior, a dynamic model of the freight train was established based on the modular method of cyclic variables, and the dynamic behavior of the freight train was simulated and analyzed under different marshaling patterns, speeds and line conditions. On-site speed-up test with different marshaling freight trains was carried out, and the stability and ride-index of the train before and after the speed-up were compared and analyzed. The feasibility of increasing the speed of freight trains with mixed marshaling of light and heavy cars was demonstrated theoretically and experimentally. The results show that the theory is in good agreement with the test, which can effectively reflect the dynamic behavior of the vehicle. The dynamic behavior of the freight train in the study meets the requirements of increasing speed to 90 km/h. This paper provides a theoretical basis and method for railway freight transportation and the speed-up of freight vehicles

Universal factorial Schur P,QP,Q-functions and their duals

We define universal factorial Schur $P,Q$-functions and their duals, which specialize to generalized (co)-homology "Schubert basis" for loop spaces of the classical groups. We also investigate some of their properties.Comment: 10 pages, old paper written in 2012.1

Analisis Kesalahan Penggunaan Ejaan Pada Skripsi Mahasiswa Program Studi Di Pendidikan Guru Sekolah Dasarfakultas Keguruan Dan Ilmu Pendidikan Universitas Darul Ulum Islamic Centre Sudirman Guppi Undaris

Penelitian ini bertujuan untuk mendeskripsikan kesalahan pemakaian huruf pada skripsi mahasiswa PGSD UNDARIS, medeskripsikan kesalahan penulisan kata pada skripsi mahasiswa PGSD UNDARIS, medeskripsikan kesalahan penulisan unsur serapan pada skripsi mahasiswa PGSD UNDARIS, dan medeskripsikan kesalahan penulisan tanda baca pada skripsi mahasiswa PGSD UNDARIS. Subjek penelitian ini adalah hasil penelitian pada skripsi mahasiswa PGSD UNDARIS.Jumlah skripsi yang dianalisis berjumlah 4 skripsi mahasiswa PGSD UNDARIS.Teknik pengumpulan data dalam penelitian ini menggunakan teknik baca.Teknik baca yang dilakukan adalah membaca secara berulang dan cermat skripsi mahasiswa PGSD UNDARIS yang telah dipilih.Sebelum dilakukan pencatatan, terlebih dahulu dilakukan pencatatan data pada kartu data, kemudian kartu data tersebut dikategorikan menurut kriteria kesalahan ejaan.Data yang terkumpul, kemudian dianalisis dan dideskripsikan.Instrumen pengumpulan data ini adalah menggunakan human instrument yaitu peneliti sendiri. Peneliti sebagai pelaksana yang akan mengumpulkan data, menganalisis, dan sekaligus membuat simpulan. Hasil penelitian ini menunjukkan bahwa kesalahan ejaan pada skripsi mahasiswa prodi PGSD Universitas Darul Ulum Islamic Centre Sudirman GUPPI sebanyak 247 kesalahan yang terdiri : (1) kesalahan pemakaian huruf kapital sebanyak 8 kesalahan, (2) kesalahan penulisan kata depan di dan ke sebanyak 30 kesalahan, yang meliputi kesalahan penulisan kata depan disebanyak 28 kesalahan, kesalahan penulisan kata depan ke sebanyak 2 kesalahan, sedangkan i mbuhan di-, ke-, dan kata depan dari tidak ditemukan kesalahan pada skripsi mahasiswa, (3) kesalahan pemakaian tanda baca sebanyak 209 kesalahan, yang meliputi kesalahan pemakaian tanda baca titik (.) sebanyak 34 kesalahan, kesalahan pemakaian tanda baca koma (,) sebanyak 163 kesalahan, kesalahan pemakaian tanda hubung (-) sebanyak 1 kesalahan, kesalahan pemakaian tanda tanya (?) sebanyak 4 kesalahan, dan kesalahan pemakaian tanda baca titik dua (:) sebanyak 8 kesalahan, dan (4) kesalahan pemakaian tanda seru (!), kesalahan pemakaian tanda baca titik koma (;), kesalahan pemakaian tanda petik tunggal (‘ ...\u27), kesalahan pemakaian tanda petik (“...”), dan kesalahan pemakaian tanda garis miring (/) tidak ditemukan kesalahan

Replication Stress Induces Micronuclei Comprising of Aggregated DNA Double-Strand Breaks

BACKGROUND: Micronuclei (MN) in mammalian cells serve as a reliable biomarker of genomic instability and genotoxic exposure. Elevation of MN is commonly observed in cells bearing intrinsic genomic instability and in normal cells exposed to genotoxic agents. DNA double-strand breaks are marked by phosphorylation of H2AX at serine 139 (γ-H2AX). One subclass of MN contains massive and uniform γ-H2AX signals. This study tested whether this subclass of MN can be induced by replication stress. PRINCIPAL FINDINGS: We observed that a large proportion of MN, from 20% to nearly 50%, showed uniform staining by antibodies against γ-H2AX, a marker of DNA double-strand breaks (DSBs). Such micronuclei were designated as MN-γ-H2AX (+). We showed that such MN can be induced by chemicals that are known to cause DNA replication stress and S phase arrest. Hydroxyurea, aphidicolin and thymidine could all significantly induce MN-γ-H2AX (+), which were formed during S phase and appeared to be derived from aggregation of DSBs. MN-γ-H2AX (-), MN that were devoid of uniform γ-H2AX signals, were induced to a lesser extent in terms of fold change. Paclitaxel, which inhibits the disassembly of microtubules, only induced MN-γ-H2AX (-). The frequency of MN-γ-H2AX (+), but not that of MN-γ-H2AX (-), was also significantly increased in cells that experience S phase prolongation due to depletion of cell cycle regulator CUL4B. Depletion of replication protein A1 (RPA1) by RNA interference resulted in an elevation of both MN-γ-H2AX (+) and MN-γ-H2AX (-). CONCLUSIONS/SIGNIFICANCE: A subclass of MN, MN-γ-H2AX (+), can be preferentially induced by replication stress. Classification of MN according to their γ-H2AX status may provide a more refined evaluation of intrinsic genomic instabilities and the various environmental genotoxicants

Distributed Equivalent Substitution Training for Large-Scale Recommender Systems

We present Distributed Equivalent Substitution (DES) training, a novel distributed training framework for large-scale recommender systems with dynamic sparse features. DES introduces fully synchronous training to large-scale recommendation system for the first time by reducing communication, thus making the training of commercial recommender systems converge faster and reach better CTR. DES requires much less communication by substituting the weights-rich operators with the computationally equivalent sub-operators and aggregating partial results instead of transmitting the huge sparse weights directly through the network. Due to the use of synchronous training on large-scale Deep Learning Recommendation Models (DLRMs), DES achieves higher AUC(Area Under ROC). We successfully apply DES training on multiple popular DLRMs of industrial scenarios. Experiments show that our implementation outperforms the state-of-the-art PS-based training framework, achieving up to 68.7% communication savings and higher throughput compared to other PS-based recommender systems.Comment: Accepted by SIGIR '2020. Proceedings of the 43rd International ACM SIGIR Conference on Research and Development in Information Retrieval. 202