Execução de sondagem pelo método SPT e rotativa estudo de caso: Obra 187-2 Allegro/  SPT and rotary drilling case study: Job site 187-2 Allegro

Considering the high investment and operation costs, reliability analysis of mining machineries is essential to achieve a lean operation and to prevent the unwanted stoppages. In open pit mining, drilling, as the initial stage of the exploitation operations, has a significant role in the other stages. Failure of drilling machines causes total delay in blasting operation. In this paper, the reliability of drilling operation has been analyzed using the Markov method. The failure and operation data of four heavy rotary drilling machines in Sarcheshme copper mine in Iran have been used as a case study. Failure rate and repair rate of all machines have been calculated using available data. Then, 16 possible operation states have been defined and the probability of being of drilling fleet in each of the states was calculated using Markov theory. The results showed that there was 77.2% probability that all machines in fleet were in operational condition. It means that, considering 360 working days per year, drilling operation will be in a reliable condition in 277.92 days.

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Integrating CAD and schedule for identification and resolution of work space conflicts between subcontractors

Canadian Journal of Civil Engineering ◽

10.1139/l01-032 ◽

2001 ◽

Vol 28 (5) ◽

pp. 759-768 ◽

Cited By ~ 1

Author(s):

Sy-Jye Guo

Keyword(s):

Decision Support ◽

Critical Path ◽

Productivity Loss ◽

Complex Problem ◽

Dynamic Identification ◽

Conflict Analysis And Resolution ◽

Job Site ◽

Alternative Space

Numerous workers, equipment, material, temporary facilities, and permanent structures share the limited space during construction. Since space constraints may affect productivity and the critical path, it is essential to organize the available space efficiently and minimize space conflicts. This study considers space availability due to time and scheduling, productivity loss due to space constraints and path interference, as well as the possibility of alternative space to resolve these conflicts and optimize space usage. Herein CAD is integrated with scheduling software for dynamic identification of space conflicts on the job site. Follow-up supplemental decision criteria are then provided for conflict analysis and resolution. A prototype decision support system, which combines the criteria, was developed to solve this significant and complex problem more efficiently and precisely. A case study demonstrates the use and development of this system, which is very helpful to engineers and project management.Key words: space, conflict, resolution, CAD, schedule.

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Evaluating 4D-BIM and VR for Effective Safety Communication and Training: A Case Study of Multilingual Construction Job-Site Crew

Buildings ◽

10.3390/buildings11080319 ◽

2021 ◽

Vol 11 (8) ◽

pp. 319

Author(s):

Muneeb Afzal ◽

Muhammad Tariq Shafiq

Keyword(s):

United Arab Emirates ◽

Management Practices ◽

Safety Management ◽

Linguistic Diversity ◽

Knowledge Exchange ◽

Safety Training ◽

Site Conditions ◽

Common Language ◽

Job Site

Effective safety management is a key aspect of managing construction projects. Current safety management practices are heavily document-oriented that rely on historical data to identify potential hazards at a construction job site. Such document-bound safety practices are prone to interpretative and communication errors in multilingual construction environments, such as in the United Arab Emirates (UAE). Applications of Building Information Models (BIM) and Virtual Reality (VR) are claimed to improve hazards identification and communication in comparison to 2-D static drawings by simulating job-site conditions and safety implications and thus can interactively educate the job-site crew to enhance their understanding of the on-site conditions and safety requirements. This paper presents findings of a case study conducted to evaluate the effectiveness of 4-Dimensional (4-D) BIM and VR in simulating job-site safety instructions for a multilingual construction crew at a project in the UAE. 4-D BIM-enabled VR simulations, in lieu of the Abu Dhabi Occupational Safety and Health Center (OSHAD) code of practice, were developed and tested through risk assessment and safety training exercises for the job-site crew. The results showed a significant improvement in the job-site crew’s ability to recognize a hazard, understand safety protocols, and incorporate proactive risk response in mitigating the hazards. This study concludes that 4-D BIM-enabled VR visualization can improve information flow and knowledge exchange in a multilingual environment where jobsite crew do not speak a common language and cannot understand written safety instructions, manuals, and documents in any common language due to linguistic diversity. The findings of this study are useful in communicating safety instructions, and safety training, in the UAE, as well as in international projects.

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Combining Ontology and Retrieval in Case-Based Reasoning for Heavy Industry Machinery Design

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.456.274 ◽

2013 ◽

Vol 456 ◽

pp. 274-277

Author(s):

Hong Lei Zhang ◽

You Hua Ge ◽

Jian Sheng Xia ◽

Xiao Feng Huang

Keyword(s):

Lead Time ◽

Case Based Reasoning ◽

Semantic Retrieval ◽

Heavy Industry ◽

Rotary Drilling ◽

Semantic Level ◽

Drilling Rig ◽

Case Based ◽

Machinery Design

The efficiency of design has significant impact on the overall lead time for the new product of heavy industry machinery. Case-based reasoning (CBR) can be used to heavy industry machinery design for improving the effectiveness of design. However, CBR is short of flexibility to cope with the semantic retrieval, which is the main cause of the decline in the efficiency and accuracy. Confronted with the problem, the approach has been developed based on the combining ontology and retrieval in case-based reasoning for heavy industry machinery design. Through incorporating ontology with CBR, the paper provides a flexible and comprehensive operation. An example case study of rotary drilling rig demonstrates the potential which the proposed method is more effective to retrieve cases on the semantic level.

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A Preliminary Evaluation of Independence in a Competitive Employment Setting

Journal of the Association for Persons with Severe Handicaps ◽

10.1177/154079698601100404 ◽

1986 ◽

Vol 11 (4) ◽

pp. 246-254 ◽

Cited By ~ 4

Author(s):

David P. Wacker ◽

Wendy K. Berg ◽

Melissa B. Visser ◽

John E. Egan ◽

Pat Berrie ◽

...

Keyword(s):

Work Environment ◽

Current Approach ◽

Preliminary Evaluation ◽

Competitive Employment ◽

Job Tasks ◽

Case Study Design ◽

Potential Benefits ◽

Improved Performance ◽

Job Site

Two students received 3 months of training at a community job site where they received minimum wage for performing clerical tasks (e.g., photocopying and mail sorting). In addition to documenting the students' improved performance on the job tasks, the students' independent demonstration of incidental behaviors was also evaluated within a case study design. Incidental behaviors were defined as any behavior that might increase independence in a job setting, but which did not receive direct instruction from staff. The results indicated that both students demonstrated increased independence in the work setting based on three qualitatively different measures of their incidental behavior. First, both students demonstrated substantial increases in their number of appropriate incidental behaviors across work days, suggesting that they were beginning to interact more appropriately with the work environment. Second, both demonstrated over 20 new incidental behaviors, suggesting that experience in the work environment resulted in collateral changes in behavior. Third, both students demonstrated a higher ratio of appropriate versus inappropriate behavior over time. The potential benefits of documenting incidental behaviors are discussed, as are limitations with the current approach.

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Box Girder Construction on Toll Road Project use Manual Program Evaluation and Review Technique (M-PERT) and Value Engineering (VE) to Performance Cost and Time Improvement

10.21203/rs.3.rs-117800/v1 ◽

2020 ◽

Author(s):

Albert Eddy Husin ◽

Diah Ika Rahmawati ◽

Myrna Meisaroh ◽

Bernadette Detty Kussumardianadewi

Keyword(s):

Program Evaluation ◽

Value Engineering ◽

Added Value ◽

Infrastructure Development ◽

Box Girder ◽

Time Efficiency ◽

Global Competitiveness ◽

Road Project ◽

Job Site

Abstract Indonesia's ranking is 72 out of 141 countries and is in 5th place in the group of countries in Southeast Asia based on the 2019 Global Competitiveness Index (GCI) by the World Economic Forum. The current development of infrastructure development is not directly proportional to an increase in the number of infrastructure users by 1.9% from an annual increase of 10%-55%. And the occurrence of implementation time experienced a delay of 11.95%. And with a low rate of return on books with high investment costs in the construction of 7.79%. The expected goal in this research is to have cost and time efficiency in implementing infrastructure development. In this study, the focus is on the upper structure work, one of which is the box girder, to improve time and cost efficiency based on the Manual Program Evaluation and Review Technique (M-PERT) and Value Engineering (VE) in the case study of this research. The case study using the M-PERT method resulted in a time efficiency value of 98.87% of the completion time at the job site, while the VE method obtained an added value of income outside toll roads of 9.38% of construction costs.

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Profit-point analysis: A tool for general contractors to measure and compare costs of management time expended on different subcontractors

Canadian Journal of Civil Engineering ◽

10.1139/l05-021 ◽

2005 ◽

Vol 32 (4) ◽

pp. 712-718 ◽

Cited By ~ 5

Author(s):

Yong-Woo Kim ◽

Glenn Ballard

Keyword(s):

Direct Costs ◽

Activity Based Costing ◽

Managerial Control ◽

Staff Time ◽

Management Efficiency ◽

General Contractor ◽

Point Analysis ◽

General Contractors ◽

Job Site

One of the trends in construction today is the increasing use of specialty contractors. As a result, projects are becoming more complicated and fragmented, more coordination is required, and overhead costs of the general contractors are increasing relative to the direct costs. Better ways of controlling job-site overhead costs are needed. This paper presents profit-point analysis (PPA), a method for analyzing how indirect staff time of a general contractor is actually spent on a project. Profit points are imaginary points where a general contractor and subcontractors are interfaced. The PPA is a method of analysis on these points, which adapts activity-based costing from manufacturing to construction. This new method, illustrated through a case study, yields valuable information for managerial control; for example, the different amount of supplemental support from the general contractor required by different subcontractors.Key words: overhead costs, cost analysis, profit points, activity-based costing (ABC), management efficiency, evaluating specialty contractors.

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The Genesis and Internal Dynamics of El Salvador's People's Revolutionary Army, 1970–1976

Behavioral and Brain Sciences ◽

10.1017/s0140525x13009850 ◽

2014 ◽

Vol 38 (01) ◽

pp. 102-129

Author(s):

ALBERTO MARTÍN ÁLVAREZ ◽

EUDALD CORTINA ORERO

Keyword(s):

Latin America ◽

El Salvador ◽

Early Years ◽

Left Wing ◽

Internal Dynamics ◽

Internal Coherence ◽

The 1960S

AbstractUsing interviews with former militants and previously unpublished documents, this article traces the genesis and internal dynamics of the Ejército Revolucionario del Pueblo (People's Revolutionary Army, ERP) in El Salvador during the early years of its existence (1970–6). This period was marked by the inability of the ERP to maintain internal coherence or any consensus on revolutionary strategy, which led to a series of splits and internal fights over control of the organisation. The evidence marshalled in this case study sheds new light on the origins of the armed Salvadorean Left and thus contributes to a wider understanding of the processes of formation and internal dynamics of armed left-wing groups that emerged from the 1960s onwards in Latin America.

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Culture and the plasticity of perception

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002887 ◽

2020 ◽

Vol 43 ◽

Author(s):

Michael Lifshitz ◽

T. M. Luhrmann

Keyword(s):

Cultural Context ◽

Sensory Experience ◽

Cultural Learning ◽

The World

Abstract Culture shapes our basic sensory experience of the world. This is particularly striking in the study of religion and psychosis, where we and others have shown that cultural context determines both the structure and content of hallucination-like events. The cultural shaping of hallucinations may provide a rich case-study for linking cultural learning with emerging prediction-based models of perception.

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Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000451 ◽

2019 ◽

Vol 42 ◽

Author(s):

Daniel J. Povinelli ◽

Gabrielle C. Glorioso ◽

Shannon L. Kuznar ◽

Mateja Pavlic

Keyword(s):

Temporal Reasoning ◽

Higher Order ◽

Important Case ◽

Human Cognition ◽

Relational Reasoning ◽

Dual Systems ◽

First Order ◽

Reasoning System ◽

Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

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