EXCAVATION ASSESSMENT IN WET TROPICALLY SEDIMENTARY ROCK

2015 ◽  
Vol 76 (2) ◽  
Author(s):  
Maybelle Liang ◽  
Edy Tonnizam Mohamad ◽  
Ibrahim Komoo ◽  
Ma Chau-Khun
Keyword(s):  
Statistical Analysis ◽  
Moisture Content ◽  
Sedimentary Rock ◽  
Geotechnical Engineering ◽  
Sedimentary Rocks ◽  
Rock Properties ◽  
Factors Affecting ◽  
Engineering Projects ◽  
Surface Excavation ◽  
Selection Of

The selection of suitable methods to be employed for surface excavation works is particularly important in geotechnical engineering projects. Factors such as environmental constrains, rock properties and size of site may affect the selection of machine required for surface excavation. Wrong selection of equipment and technique can result in unrecoverable expenses and thus, should be avoided. Great challenges in excavation works are expected in sedimentary rock where the occurrence of discontinuity such as bedding thickness, foliation and the inhomogeneity of rock as well as effect of moisture can greatly affect its excavatability. This paper aims to identify and highlight the factors affecting the excavation works in wet tropically weathered sedimentary area as what have been experienced in Malaysia. Some of these factors, however, are not specified in the existing general excavatability assessments. Assessment by practical excavation was carried out at three sedimentary rock sites in Nusajaya, Malaysia, taking into account the related parameters. Statistical analysis by using SPSS was then being conducted in order to determine the correlation of each parameter with productivity of excavation and their significance in affecting the excavatability.Based on the results obtained, it was found that the parameters such as Is50, R, UCS, density, ITS, Js, JL, Jd, IP and moisture content play significant roles in affecting the excavatability of sedimentary rocks. Meanwhile, the existence of bedding, Id2 and Jn are deemed to be neglected. It is believed that this study can help to enhance the knowledge on factors that complicate the excavation works in sedimentary areas.

Selection of factors affecting increase of non-oil export

2018 ◽  
Vol 13 (1) ◽  
pp. 45-52
Author(s):  
Aynura Manaf kizi Ismayilova ◽  
Keyword(s):  
Factors Affecting ◽  
Oil Export ◽  
Selection Of

PARAMETER OPTIMIZATION AND EXPERIMENTAL RESEARCH ON THE HAMMER MILL 锤片式粉碎机参数优化与试验研究

2020 ◽  
pp. 341-350
Author(s):  
Di Wang ◽  
Changbin He ◽  
Haiqing Tian ◽  
Liu Fei ◽  
Zhang Tao ◽  
...  
Keyword(s):  
Moisture Content ◽  
Orthogonal Experiment ◽  
Electricity Consumption ◽  
Spindle Speed ◽  
Hammer Mill ◽  
Factors Affecting ◽  
Evaluation Indexes ◽  
Grain Moisture ◽  
Validation Experiment ◽  
Corn Grain

Low productivity and high electricity consumption are considered problems of the hammer mill, which is widely used in current feed production. In this paper, the mechanical properties of corn grain ground by a hammer mill were analysed, and the key factors affecting the performance of the hammer mill were determined. The single-factor experiment and three-factor, three-level quadratic regression orthogonal experiment were carried out with the spindle speed, corn grain moisture content and number of hammers as experimental factors and the productivity and electricity consumption per ton as evaluation indexes. The results showed that the order of influence on the productivity was spindle speed > corn grain moisture content > number of hammers and that the order of influence on the electricity consumption per ton was corn grain moisture content > spindle speed > number of hammers. The parameters were optimized based on the response surface method with the following results: the spindle speed was 4306 r/min, the corn grain moisture content was 10%, and the number of hammers was 24. The validation experiment was carried out with the optimal parameters’ combination. The productivity and electricity consumption per ton were 988.12 kg/h and 5.37 kW·h/t, respectively, which were consistent with the predicted results of the model.

Regional, institutional and individual factors affecting selection of minimally invasive nephroureterectomy in Japan: A national database analysis

2012 ◽  
Vol 20 (7) ◽  
pp. 695-700 ◽  
Author(s):  
Toru Sugihara ◽  
Hideo Yasunaga ◽  
Hiromasa Horiguchi ◽  
Tetsuya Fujimura ◽  
Hiroaki Nishimatsu ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
National Database ◽  
Individual Factors ◽  
Database Analysis ◽  
Factors Affecting ◽  
Selection Of

scholarly journals The Importance of International Medical Rotations in Selection of an Otolaryngology Residency

2011 ◽  
Vol 3 (3) ◽  
pp. 414-416 ◽  
Author(s):  
Nathan H Boyd ◽  
Raul M Cruz
Keyword(s):  
Residency Program ◽  
General Interest ◽  
Factors Affecting ◽  
Residency Programs ◽  
International Elective ◽  
Program Selection ◽  
Application Service ◽  
Residency Application ◽  
Lifestyle Research ◽  
Selection Of

Abstract Background The objective of this study was to determine the extent of interest in international electives among prospective otolaryngology residents and to determine whether the availability of international electives affected students' interest in ranking a particular residency program. Methods A 3-part survey was given to all medical students enrolled in the 2008 otolaryngology match via the Electronic Residency Application Service. Part 1 elicited demographic information. Part 2 explored general interest in international rotations. Part 3 involved ranking several factors affecting students' choice of residency programs. This survey was developed at our institution, with no formal validation. Participation was anonymous and voluntary. Results A total of 307 students entered the otolaryngology match, and 55 surveys (18%) were completed. Twenty-five of 55 students (55%) had completed an international elective during or prior to medical school, and 51 of 55 respondents (93%) had a “strong” or “very strong” desire to participate in an international elective during residency; 48 of 55 students (87%) had a “strong” or “very strong” desire to participate in international surgical missions after residency. Future practice goals had no correlation with interest in international rotations, either during or after residency training. Respondents ranked 8 factors that had an impact on residency program selection in the following order of importance: operative experience, location, lifestyle, research opportunities, didactics, international electives, prestige of program, and salary. Conclusion Interest in international medicine among prospective otolaryngologists was high in this subset of respondents but did not appear to affect residency program selection.

Suitability of Natural Geomedia for Radwaste Storage

1982 ◽  
Vol 15 ◽  
Author(s):  
W. S. Fyfe
Keyword(s):  
Rock Properties ◽  
Fracture Flow ◽  
Time Prediction ◽  
Sedimentary Sequences ◽  
Rock Types ◽  
Direct Observations ◽  
Long Time ◽  
Mining Disturbance ◽  
Selection Of

ABSTRACTSelection of the best rock types for radwaste disposal will depend on their having minimal permeability, maximal flow dispersion, minimal chance of forming new wide aperture fractures, maximal ion retention, and minimal thermal and mining disturbance. While no rock is perfect, thinly bedded complex sedimentary sequences may have good properties, either as repository rocks, or as cover to a repository.Long time prediction of such favorable properties of a rock at a given site may be best modelled from studies of in situ rock properties. Fracture flow, dispersion history, and geological stability can be derived from direct observations of rocks themselves, and can provide the parameters needed for convincing demonstration of repository security for appropriate times.

scholarly journals Factors affecting nest-site selection of Sabine's Gulls in the eastern Canadian Arctic

2005 ◽  
Vol 83 (9) ◽  
pp. 1240-1245 ◽  
Author(s):  
Iain J Stenhouse ◽  
H Grant Gilchrist ◽  
William A Montevecchi
Keyword(s):  
Site Selection ◽  
Nest Site ◽  
Nest Site Selection ◽  
Breeding Habitat ◽  
Factors Affecting ◽  
Invertebrate Prey ◽  
Terrestrial Invertebrate ◽  
Individual Fitness ◽  
Sabine’S Gull ◽  
Selection Of

The selection of breeding habitat is of prime importance for individual fitness. Among birds, natural selection should favour the ability to recognize and select habitat suitable for nesting and rearing chicks. This study compares the characteristics of Sabine's Gull, Xema sabini (Sabine, 1819), nest sites with random points across a coastal tundra environment on Southampton Island, Nunavut, Canada. The availability of terrestrial invertebrate prey was also examined among habitats. Sabine's Gull nests were nonrandomly distributed in relation to vegetation, substrate, and proximity to water. Gulls nested within approximately 1 km of the coastline and selected sites with the greatest proportions of moss and standing water (i.e., they nested close to the edge of small freshwater ponds near shore). However, there were no detectable differences in characteristics between successful and unsuccessful nests within preferred habitat. The dynamics of terrestrial invertebrate prey communities varied between years, but the volume of invertebrates in Sabine's Gull nesting habitat was intermediate between the most productive habitats and the least productive habitats in both years. However, nest-site selection in Sabine's Gulls may also be influenced by the availability of aquatic invertebrates (not examined in this study) and their proximity to the marine coastline, where chicks are taken to be reared.

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