Dynamic programming algorithm for economic lot-sizing problem with bounded inventory and out-sourcing

This paper addresses a single item dynamic lot-sizing model with inventory capacity and out-sourcing. The goal is to minimize the total costs of production, setup, inventory holding and out-sourcing. Two versions of an out-sourcing model with time-varying costs are considered: stock out case and conservation case. Zero Inventory Order property has been found and some new properties are obtained in an optimal solution. Dynamic programming algorithms are developed to solve the problem in strongly polynomial time respectively. Furthermore, some numerical results demonstrate that the approach proposed is efficient and applicable.

Transforming Ideas to Explore University

With the rapid progress of informatization, the university infonnatization faces the system innovation. The paper mainly discusses the new management model and operation mode of IT department in digital campus time, as example of the campus card in University of Electronic Science and Technology of China_ The work mode of information center is transformed from cost center to profit center, and the operation mode transform from outsource service to in-sourcing.

Differences in source kitchens for lacustrine in-source and out-of-source hydrocarbon accumulations

Because of the differences of hydrocarbon accumulation between in-source and out-of-source oil pools, the demand for source kitchen is different. Based on the establishment of source-to-reservoir correlation in the known conventional accumulations, and the characteristics of shale oil source kitchens as well, this paper discusses the differences of source kitchens for the formation of both conventional and shale oils. The formation of conventional oil pools is a process of hydrocarbons enriching from disperse state under the action of buoyancy, which enables most of the oil pools to be formed outside the source kitchens. The source rock does not necessarily have high abundance of organic matter, but has to have high efficiency and enough amount of hydrocarbon expulsion. The TOC threshold of source rocks for conventional oil accumulations is 0.5%, with the best TOC window ranging from 1% to 3%. The oil pools formed inside the source kitchens, mainly shale oil, are the retention of oil and gas in the source rock and there is no large-scale hydrocarbon migration and enrichment process happened, which requires better quality and bigger scale of source rocks. The threshold of TOC for medium to high maturity of shale oil is 2%, with the best range falling in 3%–5%. Medium to low mature shale oil resource has a TOC threshold of 6%, and the higher the better in particular. The most favorable kerogen for both high and low-mature shale oils is oil-prone type of I–II1. Carrying out source rock quality and classification evaluation and looking for large-scale and high-quality source rock enrichment areas are a scientific issue that must be paid attention to when exploration activity changes from out-of-source regions to in-source kitchen areas. The purpose is to provide theoretical guidance for the upcoming shale oil enrichment area selection, economic discovery and objective evaluation of resource potential.