It is a commonly asked question:how big should the longwall shields be? The answer is a key aspect of a longwall mining feasibility study when the consequences of inadequately rated shields are considered.This paper a...It is a commonly asked question:how big should the longwall shields be? The answer is a key aspect of a longwall mining feasibility study when the consequences of inadequately rated shields are considered.This paper addresses this question based on the measured nature of the loading environment in which shields are required to operate,the various geological and geometrical controls of that environment and the various links between their load rating,a range of other relevant shield design factors and the loss event they are required to prevent a major roof collapse on the longwall face.The paper concludes that despite the tremendous advances that have been made in shield design and load rating over the past50 years,the same drivers that caused longwall miners of the past to seek improved roof control on the longwall face via the use of ever-higher rated shields,are still as relevant today.However at the current time,the limits of the largest available longwall shields have yet to be tested,therefore industry focus for the foreseeable future should possibly be in achieving the maximum level of roof control on the face via their optimum operational use rather than considering further shield rating increases and incurring the inevitable downsides in terms of capital cost and shield weight.展开更多
Human resource management is the active procedure of planned control and coordination that an organization trains, selects and evaluates human resource in the organization in order to achieve their goals and improve e...Human resource management is the active procedure of planned control and coordination that an organization trains, selects and evaluates human resource in the organization in order to achieve their goals and improve efficiency, through psychology, management, sociology and other related knowledge. Human resource management focuses on the cultivation and development of personnel. College student management also needs selection and cultivation of personnel and improve the level of student management. This paper mainly bases on our own working practices to discuss about the application of human resource management theory in the management of the college students.展开更多
In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the di...In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the direction of industry development have been found out, and the even-drive washing technology has been studied out through adoption of hyperbolic impeller and suspended inner barrel structure, as well as high-efficiency drive and innovated control design. Thereby the problems with existing washing machines such as heavy twist and wear, uneven wash of clothes, long washing time, and high water and power consumption are solved.展开更多
文摘It is a commonly asked question:how big should the longwall shields be? The answer is a key aspect of a longwall mining feasibility study when the consequences of inadequately rated shields are considered.This paper addresses this question based on the measured nature of the loading environment in which shields are required to operate,the various geological and geometrical controls of that environment and the various links between their load rating,a range of other relevant shield design factors and the loss event they are required to prevent a major roof collapse on the longwall face.The paper concludes that despite the tremendous advances that have been made in shield design and load rating over the past50 years,the same drivers that caused longwall miners of the past to seek improved roof control on the longwall face via the use of ever-higher rated shields,are still as relevant today.However at the current time,the limits of the largest available longwall shields have yet to be tested,therefore industry focus for the foreseeable future should possibly be in achieving the maximum level of roof control on the face via their optimum operational use rather than considering further shield rating increases and incurring the inevitable downsides in terms of capital cost and shield weight.
文摘Human resource management is the active procedure of planned control and coordination that an organization trains, selects and evaluates human resource in the organization in order to achieve their goals and improve efficiency, through psychology, management, sociology and other related knowledge. Human resource management focuses on the cultivation and development of personnel. College student management also needs selection and cultivation of personnel and improve the level of student management. This paper mainly bases on our own working practices to discuss about the application of human resource management theory in the management of the college students.
文摘In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the direction of industry development have been found out, and the even-drive washing technology has been studied out through adoption of hyperbolic impeller and suspended inner barrel structure, as well as high-efficiency drive and innovated control design. Thereby the problems with existing washing machines such as heavy twist and wear, uneven wash of clothes, long washing time, and high water and power consumption are solved.
