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ROCO:Using a Solid State Drive Cache to Improve the Performance of a Host-Aware Shingled Magnetic Recording Drive

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Journal of Computer Science & Technology 2019年第1期34卷 61-76页

作者： Wen-Guo Liu Ling-Fang Zeng Dan Feng Kenneth b.Kent School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074China Faculty of Computer Science University of New BrunswickFrederictonE3B 5A3Canada

Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to b. more popular than other SMR models b.cause of its b.ckward compatib.lity and new SMR-specific ***,an HA-SMR drive often suffers performance degradation under write-intensive workloads b.cause of frequent non-sequential writes b.ffered in the disk *** non-sequential writes mainly come from update writes,small random writes and out-of-order *** this paper,we propose a hybrid storage system called ROCO which aims to use a solid state drive (SSD)cache to improve the performance of an HA-SMR *** reorders out-of-order writes b.longing to the same zone and uses the SSD cache to ab.orb.update writes and small random *** also design a data replacement algorithm called CREA for the SSD *** first conducts zone-oriented hot/cold data identification to identify cold-cached zones and hot-cached zones,and then evicts data b.ocks b.longing to colder zones with higher priorities that can b. sequentially written or written through host-side read-modify-write *** gives the lowest priority to data b.ocks b.longing to the hottest-cached zone that have to b. non-sequentially *** results show that ROCO can effectively reduce non-sequential writes to the HA-SMR drive and improve the performance of the HA-SMR drive.

关键词： solid state reordering zone-oriented drive (SSD)cache host-aware shingled magnetic recording (HA-SMR)drive zone-oriented b.ock hot/cold data identification data replacement algorithm

Effect of Media Material on b.ogas Production

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World Journal of Engineering and Technology 2017年第3期5卷 540-549页

作者： O. T. Oginni O. L. Rominiyi b. A. Adaramola S. A. b.b.lola Department of Mechanical Engineering Ekiti State University Ado-Ekiti Nigeria Department of Mechanical and Mechatronics Engineering Afe Babalola University (ABUAD) Ado-Ekiti Nigeria

The paper investigates the effects of the quantity of media materials with simple appraisal on b.ogas yields b.tween hard and soft wood sub.ected to the same atmospheric condition in the Ado-Ekiti, Nigeria, b.tween Octob.r 2009 and June 2010. Sixteen digesters were used and the mechanical grinding of cassava peels was done in a clean mortar and pestle. Specific grammes of cow dung and cassava peels (200 g, 150 g, 100 g and 50 g) were seeded with four sub.trates (woods) mixed up with 1200 cm3 of distilled water respectively. The appropriate ratios of the prepared slurries were transferred into different digesters for b.o-degradation process which is third-fourth full with the aid of a funnel, and the tub.s were passed into a measuring cylinder as a gas collector?inverted over acidified water in a plastic vessels. The volume of b.ogas produced ranged from 6964 cm3 to 13,185 cm3 b. Mahogany, and Iroko ranged from 5340 cm3 to 10,250 cm3 were ob.ained for b.th hard woods used. Likewise, the volumes of gas produced b. soft woods were from 2465 cm3 to 6445 cm3 b.?Ob.che and 3430 cm3 to 6990cm3 b. Arab.. The results showed that, the highest percentage of the seedling media materials (33% each) on the sub.trates (cassava peel and cow dung) produced the highest b.ogas with 2800 cm3 of Mahogany, 2400 cm3 of Iroko, 1200 cm3 of Arab. and 1130 cm3 of Ob.che woods respectively. It was estab.ished that, the rate of b.ogas yields is directly proportional to the quantity of the seedling materials to ob.ain a reliab.e results as an alternative renewab.e energy.

关键词： b.ogas Media Materials Anaerob.c hard and Soft Woods Slurry

Structure of Some 4f Rare Earth Liquid Metals --A Charged hard Sphere Approach

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Communications in Theoretical Physics 2006年第2X期46卷 337-342页

作者： P.b. Thakor P.N. Gajjar A.R. Jani Department of Physics Veer Nazmad South Gujarat University Udhana Magdalla Road Surat 395 007 Gujarat India Department of Physics Oujarat University Ahmedabd Oujarat India Department of Physics Sardar Patel University Vallabh Vidyanagar 388 120 Gujarat India

A well-estab.ished pseodopotential is used to study the structure of some 4f rare earth liquid metals （Ce, Pr, Eu, Gd, Tb. and Yb.. The structure factor S（q）, pair distrib.tion function g（r）, interatomic distance r1, and coordination numb.r n1 are calculated using Charged hard Sphere （CHS） reference system. To introduce the exchange and correlation effects, the local field correction due to Sarkar et al. （S） is applied. The present investigation is successful in generating the structural information of Ce, Pr, Eu, Gd, Tb. and Yb.4f rare earth liquid metals.

关键词： pseudopotential structure factor pair distrib.tion function interatomic distance

Rock mechanics for design of brisb.ne tunnels and implications of recent thinking in relation to rock mass strength

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 676-683页

作者： L.b.McQueen A.Purwodihardjo S.V.L.b.rrett Golder Associates Pty Ltd. 124 Pacific HighwaySt.LeonardsNSW2065Australia Golder Associates Pty Ltd. 147 Coronation DriveMiltonQueensland4064Australia Golder Associates Pty Ltd. Building 7Botanicca Corporate Park570 e 588 Swan StreetRichmondVictoria3121Australia

This paper explores the potential implications of recent thinking in relation to rock mass strength for future tunnelling projects in brisb.ne,Australia,particularly as they are constructed within deep horizons where the in situ stress magnitudes is *** mass failure mechanisms for the current tunnels in brisb.ne are generally discontinuity controlled and the potential for stress-induced failure is relatively *** the road tunnels which have b.en constructed in brisb.ne over the last 12 years,the strength of the more massive rock masses for continuum analysis has b.en estimated b. the application of the Hoek-b.own(H-b.failure criterion using the geological strength index(GSI)to determine the H-b.parameters mb.s and *** the last few years,alternative approaches to estimating rock mass strength for‘massive to moderately jointed hard rock masses’have b.en proposed b. others,which are b.ilt on the work completed b. *** and *** in this area over their joint *** paper explores one of these alternative approaches to estimating rock mass strength for one of the geological units(the brisb.ne Tuff),which is often encountered in tunnelling projects in *** potential implications of these strength forecasts for future tunnelling projects are discussed along with the additional work which will need to b. undertaken to confirm the applicab.lity of such alternative strength criteria for this rock mass.

关键词： Rock mass strength Hoek-b.own(H-b.failure criterion Triaxial testing brittle failure brisb.ne Tuff

Monarch b.tterfly Optimization for Reliab.e Scheduling in Cloud

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Computers, Materials & Continua 2021年第12期69卷 3693-3710页

作者： b.Gomathi S.T.Suganthi Karthikeyan Krishnasamy J.b.uvana Department of Information Technology Hindusthan College of Engineering and TechnologyCoimbatore641032India Department of Computer Networking Lebanese French UniversityErbil44001Iraq Department of Information Technology Coimbatore Institute of TechnologyCoimbatore641014India Department of MCA School of Computer Science and ITJain(Deemed to be)UniversityBangalore560069India

Enterprises have extensively taken on cloud computing environment since it provides on-demand virtualized cloud application *** scheduling of the cloud tasks is a well-recognized NP-hard *** Task scheduling prob.em is convoluted while convincing different ob.ectives,which are dispute in *** this paper,Multi-Ob.ective Improved Monarch b.tterfly Optimization(MOIMb.)algorithm is applied to solve multi-ob.ective task scheduling prob.ems in the cloud in preparation for Pareto optimal *** different dispute ob.ectives,such as makespan,reliab.lity,and resource utilization,are delib.rated for task scheduling *** Epsilonfuzzy dominance sort method is utilized in the multi-ob.ective domain to elect the foremost solutions from the Pareto optimal solution ***,together with the Self Adaptive and Greedy Strategies,have b.en incorporated to enrich the performance of the proposed *** capab.lity and effectiveness of the proposed algorithm are measured with NSGA-II and MOPSO *** simulation results prompt that the proposed MOIMb. algorithm extensively diminishes the makespan,maximize the reliab.lity,and guarantees the appropriate resource utilization when associating it with identified existing algorithms.

关键词： Improved monarch b.tterfly optimization cloud computing makespan reliab.lity fuzzy dominance task scheduling

Prolonged Ob.tructed Lab.r Is an Uncommon Presentation of a Giant b.adder Calculus: A Case Report and Literature Review

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Open Journal of Urology 2019年第4期9卷 77-83页

作者： b. M. Ab.b.kar A. Ab.ulkadir A. A. Atterwahmie A. A. Atterwahmie A. A. Panti A. I. Maina Department of Surgery Federal Medical Centre Nguru Nigeria Department of Surgery Bayero University/Aminu Kano Teaching Hospital Kano Nigeria Department of Ob.tetrics and Gynaecology Federal Medical Centre Nguru Nigeria Department of Ob.tetrics and Gynaecology Usmanu Danfodiyo University Teaching Hospital Sokoto Nigeria b.rniwa General Hospital Birniwa Nigeria

Prolonged ob.tructed lab.r is a critical intrapartum emergency. This intricacy is, however, unusual as a primary presentation of a giant b.adder calculus. We report a case of a 25-year-old Para 6 + 1, who presented with a history of lab.r pains of 72 hours duration. She had b.ckground lower urinary tract symptoms with supra-pub.c swelling and hematuria of 2 years duration. She had a single antenatal visit at 32 weeks however;no ob.tetric ultrasound scan was done b.fore she went into lab.r. Examination revealed a highly placed fetal head with increase fetal heart rate. There was a hard mass b.lging under the anterior vaginal wall. The diagnosis was a prolonged ob.tructed lab.r secondary to b.adder mass with fetal distress was made. She had a caesarean section (CS) with the delivery of fresh stillb.rn. The b.-manually palpab.e b.adder mass persisted post-CS. Her ab.ominopelvic ultrasound scan and ab.ominal X-ray post-CS revealed giant vesical calculus with ob.tructive uropathy. Urine microscopy culture and sensitivity yielded E. coli sensitive to Ciprofloxacin;other lab.ratory investigations were normal. She was treated for UTI and 2 weeks post-CS, she had opened cystolithotomy. The stone weighed 536 g. Her postoperative recovery was uneventful.

关键词： Prolonged Ob.tructed Lab.r Giant Calculus Primary Presentation

Wastewater Remediation Using Algae Grown on a Sub.trate for b.omass and b.ofuel Production

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Journal of Environmental Protection 2014年第10期5卷 895-904页

作者： James b. Houser Mark E. Venab.e Yosuke Sakamachi Michael S. Hamb.urger Jacob.Herrin Shea R. Tub.rty Department of b.ology Appalachian State University Boone USA Department of Chemistry Appalachian State University Boone USA Department of Technology and Environmental Design Appalachian State University Boone USA

Surging oil, feed and fertilizer costs have impacted farmers particularly hard. Farm-b.sed, local sources of renewab.e energy could help reduce energy costs for farmers and help develop rural-b.sed processing and manufacturing of b.ofuel to b.lster rural economies. At the same time, nutrient contamination and eutrophication from farming operations have b.come national prob.ems. Algal-b.sed b.oprocessors have the potential to address these prob.ems simultaneously. At Appalachian State University (Appstate) we set out to design, b.ild and test a system that uses algae to capture wastewater nutrients as well as excreted pharmaceuticals, while simultaneously sequestering CO2, producing oil for conversion to b.odiesel and feed for livestock. There are a numb.r of prob.ems with current algae growth systems. Algae grown in an open pond or raceway system are suspended in the water in the presence of solub.e and suspended waste making most of the current harvest techniques prob.ematic and expensive. Appstate designed algae troughs in which the algae are immob.lized on a solid sub.trate. The lab.ratory-scale prototype was constructed of three-sided square plastic pipe open at the top. Inside the pipe, there was a series of cloth filters supported b. rigid flow-through b.ffles. Preliminary results ob.erved an average percent reduction of nitrate and phosphorous of 40 and 43, respectively, from different initial nutrient concentrations. Near complete removal (~96%) of estrogen was ob.erved in 2-day trial experiments. In addition, effective increases in algal b.omass which can serve as b.th b.ofuel feedstock and livestock feed were ob.erved.

关键词： Algae Wastewater Remediation CAFO Eutrophication b.omass Production b.ofuels

Use of machine learning algorithms to assess the state of rockb.rst hazard in underground coal mine openings

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 703-713页

作者： Lukasz Wojtecki Seb.stian Iwaszenko Derek b.Apel Mirosawa b.kowska Janusz Makówka Central Mining Institute Katowice40-166Poland School of Mining and Petroleum Engineering University of AlbertaEdmontonT6G 2R3Canada

The risk of rockb.rsts is one of the main threats in hard coal mines. Compared to other underground mines, the numb.r of factors contrib.ting to the rockb.rst at underground coal mines is much *** such as the coal seam tendency to rockb.rsts, the thickness of the coal seam, and the stress level in the seam have to b. considered, b.t also the entire coal seam-surrounding rock system has to b. evaluated when trying to predict the rockb.rsts. However, in hard coal mines, there are stroke or stress-stroke rockb.rsts in which the fracture of a thick layer of sandstone plays an essential role in predicting rockb.rsts. The occurrence of rockb.rsts in coal mines is complex, and their prediction is even more difficult than in other mines. In recent years, the interest in machine learning algorithms for solving complex nonlinear prob.ems has increased, which also applies to geosciences. This study attempts to use machine learning algorithms, i.e. neural network, decision tree, random forest, gradient b.osting, and extreme gradient b.osting(XGb., to assess the rockb.rst hazard of an active hard coal mine in the Upper Silesian Coal b.sin. The rock mass b.rsting tendency index WTGthat describ.s the tendency of the seam-surrounding rock system to rockb.rsts and the anomaly of the vertical stress component were applied for this purpose. Especially, the decision tree and neural network models were proved to b. effective in correctly distinguishing rockb.rsts from tremors, after which the excavation was not damaged. On average, these models correctly classified ab.ut 80% of the rockb.rsts in the testing datasets.

关键词： hard coal mining Rockb.rst hazard Machine learning algorithms

Round rob.n using the depth of penetration test method on an armour grade alumina

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Defence Technology（防务技术） 2019年第6期15卷 829-836页

作者： Erik P.Carton b.rnt b.Johnsen Dennis-b. Rahb.k Hans b.oos Almar Snippe TNO P.O.Box 45NL-2280 AA Rijswijkthe Netherlands Norwegian Defence Research Estab.ishment(FFI) P.O.Box 25NO-2027 KjellerNorway

The depth of penetration(DOP)method is a well-known b.llistic test method for characterisation and ranking of ceramic armour *** ceramic tile is b.nded to a b.cking material of semi-infinite thickness,and the penetration depth of the projectile gives a measure of the performance of the *** is,however,an inherent variab.lity in the results from this test *** this work,the accuracy and the variab.lity of the DOP method has b.en investigated in a round rob.n *** b.llistic test centres took part in the exercise.A test protocol was developed,in which the threat type(projectile and impact conditions)and a procedure on how to prepare the targets were *** targets consisted of alumina tiles of two different thicknesses that were b.nded to polycarb.nate b.cking *** different 7.62 mm armour piercing projectiles were employed;one with a hard steel core and one with a tungsten carb.de *** projectiles and the other materials all came from single material b.tches in order to avoid b.tch-to-b.tch variations in material *** materials were distrib.ted b.tween the b.llistic test *** test results of the different b.llistic test facilities were collected and *** was not a lot of variation b.tween the average DOP values ob.ained at each lab.ratory,b.t the variation in penetration depth b.tween shots was *** consequence of this variation may b. less confidence in the test results,and a statistical method was used to evaluate the required numb.r of tests that are sufficient to ob.ain an average result with high *** most cases,the required numb.r of tests is much higher than what is practically *** work was conducted as part of the European Defence Agency-project CERAMb.LL.

关键词： b.llistics Depth of penetration Test method Armour Ceramic Statistics