Technological aspects of technogenic disturbance liquidation in the areas of coal-gas deposits development

The objective of this work is to develop the technological measures for liquidation of technogenic disturbances that have arisen within the residential areas. Based on the results of geophysical studies, the causes and factors of Earth’s surface caving occurrence that arose in the result of natural-technogenic processes activation in underworked massif and are caused by the soil subsidence under buildings and constructions, have been determined. The solution of the problem was carried out with the use of methods for observing the natural pulsed electromagnetic field of the Earth and electric tomography in the area adjacent to the place of caving. The conclusions about the possible causes of the caving trough formation and its further development have been formulated, as well as the technological scheme for its liquidation have been developed. The developed new technological scheme allows conducting the effective liquidation works in conditions of proximity to the residential buildings and maximally reduces these scopes of works at ecological and protective measures

Experimental Analysis of Algorithms for Coflow Scheduling

Modern data centers face new scheduling challenges in optimizing job-level performance objectives, where a significant challenge is the scheduling of highly parallel data flows with a common performance goal (e.g., the shuffle operations in MapReduce applications). Chowdhury and Stoica introduced the coflow abstraction to capture these parallel communication patterns, and Chowdhury et al. proposed effective heuristics to schedule coflows efficiently. In our previous paper, we considered the strongly NP-hard problem of minimizing the total weighted completion time of coflows with release dates, and developed the first polynomial-time scheduling algorithms with O(1)-approximation ratios. In this paper, we carry out a comprehensive experimental analysis on a Facebook trace and extensive simulated instances to evaluate the practical performance of several algorithms for coflow scheduling, including the approximation algorithms developed in our previous paper. Our experiments suggest that simple algorithms provide effective approximations of the optimal, and that the performance of our approximation algorithms is relatively robust, near optimal, and always among the best compared with the other algorithms, in both the offline and online settings.Comment: 29 pages, 8 figures, 11 table

The behaviour of a two-component backfilling grout used in a Tunnel-Boring Machine

The instantaneous filling of the annulus that is created behind the segment lining at the end of the tail during the TBM advance is an operation of paramount importance. Its main goal is to minimize the surface settlements due to any over-excavation generated by the passage of the TBM. To correctly achieve the goals, a simultaneous backfilling system and the injected material should satisfy the technical, operational and performance characteristics. A two-component system injection for the back-filling is progressively substituting the use of traditional mortars. In this paper different systems of back-filling grout and in particular the two-component system are analyzed and the results of laboratory tests are presented and discusse

Technology development of Kryvyi Rih iron ore open pits within zones stoping of underground mine working

На современном этапе отработка залежей железных руд в Кривбассе ведется в условиях как совместных открытых и подземных горных работ, так и открытой разработки месторождений в зонах, подработанных подземными выработками. Приведенные технология и новые способы и устройства погашения воронок обрушения в пределах рабочей зоны карьеров путем засыпки их рядовыми скальными породами вскрыши непосредственно с поверхности, что позволяет существенно повысить безопасность горных работ в карьере и получить значительную экономию за счет предупреждения нарушения окружающей среды внешними отвалами.На сучасному етапі відробка покладів залізних руд у Кривбасі ведеться в умовах як сумісних відкритих і підземних гірничих робіт, так і відкритої розробки родовищ у зонах, що підроблені підземними виробками. Наведені технологія й нові способи та пристрої погашення вирв обрушення у межах робочої зони кар’єрів шляхом засипки їх рядовими скельними породами розкриву безпосередньо з поверхні, що дозволяє суттєво підвищити безпеку гірничих робіт у кар’єрі й отримати значну економію за рахунок попередження порушення довкілля зовнішніми відвалами.At present iron ore in Kryvbas is mined by both a combination of open pit and underground methods and by the open pit method in zones underworked by underground mining. The suggested technology and new methods of backfilling pit craters within the pit working area with rock overburden directly from the surface that enables substantial increase of mine safety and economy due to preventing environmental damage caused by surface dumps

Antechamber facilitates loading and unloading of vacuum furnace

Antechamber facilitates the use of a furnace in which materials are heat treated in a high vacuum or a gas atmosphere. It has a high vacuum pumping system, a means for backfilling with a selected gas, an access door, glove ports, and a motor driven platform

The Organization and Role During Locomotion of the Proximal Musculature of the Cricket Foreleg : I. Anatomy and Innervation

The structure of the proximal segments of the cricket (Gryllus bimaculatus) foreleg, together with the associated musculature and its innervation are described. The morphology of 50 motor neurones involved in the control of this musculature has been revealed using backfilling techniques with cobalt, horseradish peroxidase and Lucifer Yellow. The ‘ball and socket’ pleurocoxal joint is moved by three sets of anatomical antagonists (promotor-remotor, abductor-adductor, anterior-posterior rotator muscles) inserted on each side of the three axes of rotation. The axial coxotrochanteral joint is moved by the intrinsic levator and the depressor muscles; these depressors are composed of an intrinsic (coxotrochanteral) and a ‘double’ (pleurotrochanteral) subgroup. The double depressors, and all the muscles inserting on the trochantin (promotors) or the anterior coxal rim (adductor, abductors, anterior rotators) are supplied by at least eighteen neurones, whose axons run in nerve 3. The muscles that insert on the posterior coxal rim (remotors, posterior rotators) are innervated by at least twelve similar neurones whose axons run in nerve 4. The intrinsic coxal muscles are supplied by branches of nerve 5 (ten motor neurones to the levators, two to the depressors). Three presumably common inhibitors, and one Dorsal Unpaired Median (DUM) neurone have also been found