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1

Analyzing dynamic behavior of land use and land surface temperature in the city of Imphal, India

Neog Rituraj

Acta Geophysica

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2021

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Vol. 69, no. 6

2275--2290

EN

The study has been conducted over the Imphal city using multi-temporal satellite imageries. The study investigated the pattern land surface temperature (LST) development over the hill city of Imphal and its relation to land use pattern and population density. The result revealed an ascending growth of LST as a consequence of population growth and rapid land use dynamics. The Imphal city exhibited a remarkable change in the land use structure, especially in the built-up land, vegetation and crop land. Addition of built-up land of 667.44 hectares in the city territory has consequently upsurged the mean LST of the city from 23.23 °C to 30.30 °C in summer and 14.74–18.10 °C in winter during the period of 26 years (1994–2020). Summer season witnessed a consistently increasing intensity of LST in the city whereas winter depicted a completely opposite scenario during 1994–2020. Among all the land use classes, built-up land expressed maximum LST dynamics in both seasons during the period 1994 to 2020. The high positive correlation coefficient between built-up land with LST and strong negative correlation between vegetation cover and LST paved the way for maximum LST development in the city province.

2

Postać wióra przy toczeniu wzdłużnym stopu niklu w warunkach powstawania narostu

Zębala W., Słodki B., Struzikiewicz G.

Mechanik

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2016

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R. 89, nr 10

1428--1429

PL

Artykuł opisuje badania toczenia stopu Inconel 625. Stwierdzono powstawanie narostu, który zmienia geometrię ostrza, co wpływa m.in. na pogorszenie postaci wióra. Przeprowadzono pomiary zużycia ostrza VB oraz wielkości i kształtu narostu. W ramach badań modelowych obliczono maksymalną temperaturę i naprężenie w okolicy krawędzi skrawającej.

EN

Research on Inconel 625 turning was described. It was found the formation of BUE phenomenon which changes the cutting edge geometry and deteriorates chip form. VB indicator of tool wear, BUE size and its shape were measured. The maximum temperature and tension in the area of the cutting edge were calculated with the help of cutting process modeling.

3

Build Up Edge phenomenon and chip forms in Inconel 625 alloy longitudinal turning – case study

Słodki B.

Czasopismo Techniczne. Mechanika

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2016

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Y. 113, iss. 5-M

103--112

EN

The paper presents the wear process of a carbide insert in Inconel 625 longitudinal turning as well as examples of chip forms. Inconel 625 alloy belongs to the difficult-to-cut material group and causes many problems in machining operations in industry. A major one concerns chip forms produced in turning operations and quick wear of the cutting edge. The conveyed research also revealed the Build Up Edge (BUE) phenomenon, which took place in conveyed tests. A few examples have been presented and analyzed.

PL

W artykule przedstawiono proces zużycia płytki z węglików spiekanych oraz postacie wiórów uzyskanych podczas toczenia wzdłużnego stopu Inconel 625. Inconel 625 należy do grupy materiałów trudnoskrawalnych i sprawia sporo problemów w obróbce skrawaniem. Dotyczą one głównie trudności w uzyskiwaniu korzystnej postaci wiórów i bardzo szybkie zużycie ostrza. Przeprowadzone badania ujawniły także zjawisko powstawania narostu na krawędzi skrawającej. Zaprezentowano i przeanalizowano kilka przykładów.

4

Tribologiczne aspekty procesu skrawania narzędziami z niskostopowej stali szybkotnącej SW3S2

Jaworski J.

Tribologia

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2008

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nr 2

215-222

EN

The way of wear or destruction of the tool determines the material selection for a proper tool. This selection is facilitated by the characteristics, which determine relations between the structure and the properties of the tool material, on the one hand, and the tool working conditions and the way of wear, on the other. The permissible cutting speed level is determined primarily by the temperature at the contact surface of the tool and the stock material. There is a relationship between the temperature and wear of the cutting edge surface of the tool caused by a progressive loss of its hardness. When the temperature in the cutting process exceeds the value at which the cutting edge of the tool loses its hardness, then dynamic recrystallization causes its immediate catastrophic wear, even at a small value of dullness. The nature of temperature distribution qualifies the place of the wear of the cutting edge. At a small cut layer thickness the maximum temperature occurs near the cutting edge which is the reason of wear of the cutting edge on the flank. Together with the raising thickness of the cut layer, the highest temperature moves away from the cutting edge and its centre lies in the place of contact of the chip and the rake surface. For such cutting conditions, wear in the form of a groove on the rake surface is characteristic. For the same tool material and stock material the thickness of the cut layer has an influence on the temperature distribution, and the cutting speed has an influence - on the value of the temperature. It is known that the growth of cut layer thickness is followed by high increase of build-up and, simultaneously, the range of cutting speeds restricts, where it occurs. Figure 2 shows the cutting forces, the length of contact line bu and chip upset coefficient, for the edges made of SW3S2, which are less than for those made of SW7M. A decrease of the parameters becomes more intensive at the higher cutting speeds, out of the range of build-up creating, vc>60 m/min for both kind of steel. The mean friction coefficient on the friction surface is the basic factor influencing on build-up creating. As it is shown in Fig. 3, the build-ups, occurring in the conditions, are different from one another. On the edge of cuter, made of SW7M, a massive and high buildup occurs which enlarges the tool rake. A build-up with the shape prevents the tool flank against direct contact with the cutting surface and facilitates the chip rising process. The height of the buildup, on the cutting edge made of SW3S2, is smaller so it can be supposed that its influence on decrease of friction on the tool flank is inconsiderable which prevents the cutter against the heat created in the area of rising chip. Consequently the maximum temperature in the cutter rises in the vicinity of the side cutting edge under the base of the build-up. It was shown experimentally that for the thick cut layers the build-up mainly determines the position of the point of the highest temperature on the cutting edge.

5

Narosty w zespole urabiania wielonaczyniowych koparek kołowych

Szepietowski W.

Górnictwo Odkrywkowe

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2004

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R. 46, nr 1

26-28

PL

Opisano problem tworzenia się narostów urobku na elementach zespołu urabiania wielonaczyniowej koparki kołowej. Omówiono stosowane sposoby walki z powstawaniem narostów oraz podano zalecane przez normy obliczeniowe wartości obciążeń koła czerpakowego w wyniku ciężaru mogących utworzyć się narostów.

EN

Paper describes problems of accretions accumulations on working units in bucket-wheel excavators. Common mitigation methods for accretions problem are described together with recommended, by calculation norms, load values on bucket wheel resulting from accumulation of accretions.

6

Analiza doświadczalna zjawiska narostu podczas toczenia

Jóźwik J., Domińczuk J.

Eksploatacja i Niezawodność

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2001

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nr 5

53-57

PL

W artykule przedstawiono wyniki badań zjawiska narostu, przeprowadzonych w Katedrze Podstaw Inżynierii Produkcji Politechniki Lubelskiej. Charakterystyczne wielkości geometrycznych tworzonego narostu analizowano przy zastosowaniu systemu do cyfrowej analizy obrazu MICROSCAN. W postaci obrazów wizyjnych oraz wykresów przedstawiono charakter zmian wybranych parametrów geometrycznych powstającego narostu oraz uzyskane wartości parametrów chropowatości powierzchni po obróbce.

EN

The results of built-up edge effect researches, effected in Department of Production Engineering Principles at Lublin Institute of Technology are presented in this article. Characteristic geometrical sizes of arisen built-up edge were subject to analysis with usage of MICRO SCAN, digital analysis system of picture. The character of changes of selected geometric parameters of arising built-up edge and obtained values of surface roughness parameters after machining are shown in form of visional pictures and graphs.