We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a c...We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a container. Such a forwarder can shorten the loading and untoading times and improve operational efficiency. We examined two operation systems with an arm roll forwarder and a forwarder. In the first system the loading was done with a grapple-loader. In the second system the loading was done with a processor. The loading times of an arm roll forwarder were significantly tess than those of a forwarder. Because the optimal cycle times (excluding the waiting times for an arm roll for- warder) were significantly reduced, the costs of using an arm roll for- warder are lower, although the loading capacity was small and the hourly operation cost was high. The maximum operational efficiencies varied depending on forwarding distances. The second operation system with an arm roll forwarder exhibited the best operational efficiency within a 1,580-m forwarding distance, and beyond that distance it exhibited the highest operational efficiency when a forwarder was used. Similarly, the cost of operation of the system with an arm roll forwarder was the lowest within a 1,130-m forwarding distance, and beyond that distance the cost was the lowest when using the forwarder. Therefore, the arm roll for- warder is effective within a certain forwarding distance.展开更多
This article brings forward a new conception of dynamic sunk cost, and then constructs a systematic model that could be used in analyzing equipment renewal opportunity. This model will do much help in solving problems...This article brings forward a new conception of dynamic sunk cost, and then constructs a systematic model that could be used in analyzing equipment renewal opportunity. This model will do much help in solving problems refer to optimizing equipment renewal opportunity in right way.展开更多
针对14.2 mm X70管线钢,采用超快冷工艺方法,研究了节约型成分设计条件下,轧后冷却制度对14.2 mm X70管线钢显微组织及力学性能的影响。研究表明,在降低Nb 20%~30%情况下,利用轧后超快冷能够获得理想的X70显微组织及力学性能,并获得了14...针对14.2 mm X70管线钢,采用超快冷工艺方法,研究了节约型成分设计条件下,轧后冷却制度对14.2 mm X70管线钢显微组织及力学性能的影响。研究表明,在降低Nb 20%~30%情况下,利用轧后超快冷能够获得理想的X70显微组织及力学性能,并获得了14.2 mm X70合理的减量化轧制工艺。工业化大批量生产实践表明,超快冷下减量化14.2 mm X70管线钢力学性能良好稳定,很好地满足了生产需求。展开更多
文摘We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a container. Such a forwarder can shorten the loading and untoading times and improve operational efficiency. We examined two operation systems with an arm roll forwarder and a forwarder. In the first system the loading was done with a grapple-loader. In the second system the loading was done with a processor. The loading times of an arm roll forwarder were significantly tess than those of a forwarder. Because the optimal cycle times (excluding the waiting times for an arm roll for- warder) were significantly reduced, the costs of using an arm roll for- warder are lower, although the loading capacity was small and the hourly operation cost was high. The maximum operational efficiencies varied depending on forwarding distances. The second operation system with an arm roll forwarder exhibited the best operational efficiency within a 1,580-m forwarding distance, and beyond that distance it exhibited the highest operational efficiency when a forwarder was used. Similarly, the cost of operation of the system with an arm roll forwarder was the lowest within a 1,130-m forwarding distance, and beyond that distance the cost was the lowest when using the forwarder. Therefore, the arm roll for- warder is effective within a certain forwarding distance.
文摘This article brings forward a new conception of dynamic sunk cost, and then constructs a systematic model that could be used in analyzing equipment renewal opportunity. This model will do much help in solving problems refer to optimizing equipment renewal opportunity in right way.
文摘针对14.2 mm X70管线钢,采用超快冷工艺方法,研究了节约型成分设计条件下,轧后冷却制度对14.2 mm X70管线钢显微组织及力学性能的影响。研究表明,在降低Nb 20%~30%情况下,利用轧后超快冷能够获得理想的X70显微组织及力学性能,并获得了14.2 mm X70合理的减量化轧制工艺。工业化大批量生产实践表明,超快冷下减量化14.2 mm X70管线钢力学性能良好稳定,很好地满足了生产需求。