深层天然气藏开发决策风险性经济评价方法研究

随着我国环境保护、优化能源结构和可持续发展战略的实施，天然气的开发、利用在国民经济中的作用越来越突出。本文首次采用量本利分析和概率统计法对大庆长坦以东昌德深层天然气藏开发风险性进行了科学评估，方法新颖，评估结果可信度高，为政府和企业提供了量化的决策依据。     

低渗透油藏深部调剖工艺技术与质量控制

低渗透油田注水开发已逐渐成为石油开采的重要组成部分,如何控制含水上升,减缓产量递减,增加采收率,提高开发效果,是油田开发工作者最关注的问题。注水井调剖技术作为控水稳油的重要手段之一,在低渗透油田开发过程中逐渐得到了推广应用,通过对其过程控制,提高作业质量,保证措施效果。从措施选井选层入手,针对该项工艺技术关键及要点,分析质量控制的方法,论述调剖作业通过对地层深部的封堵,改变注入水流向,有效驱替剩余油,提高低渗透油田注水开发采收率。     

复合支护技术在深水平破碎岩层中的应用

深部破碎巷道具有非线性大变形特征,单一的支护方式难以控制。矿井在进入深部开采后,软岩巷道围岩出现显著变形,围岩破碎严重,对巷道围岩稳定性的控制变得极其困难。针对平煤四矿三水平上部变电所岩性较为破碎的特点,通过理论分析和对以往成功经验的借签,提出了采用锚网喷+锚索+U型钢支架+喷浆的支护技术,加强了深部破碎岩巷的支护,较好地解决了围岩松软破碎、高变形巷道的支护难题,为其它类似条件下巷道围岩控制提供了参考。     

Students' experiences of learning in a third-year management accounting class: Evidence from New Zealand

An extensive body of literature in higher education (for example, Marton and Säljö, 1984; Prosser and Trigwell, 1999) explores learning from the perspectives of students. Säljö (1979) formed the basis of Sharma's (1997) first study exploring accountancy students' conceptions of learning. Using an open-ended questionnaire administered to third-year management accounting students, this paper investigates accountancy students' conceptions of learning, and extends Sharma's (1997) study by examining the relationship between conceptions of and approaches to learning, and more specifically students' contextual experiences of learning in lectures and tutorials. Findings indicate that, while some students seek understanding as an outcome of their learning, the majority perceive learning quantitatively in terms of knowledge acquisition, reproduction and application. A new classification of the locus of responsibility for learning as perceived by students suggests that a more distributed concept of responsibility might result in enhanced learning outcomes.     

The Case for Accounting Education Research

Pressures on the unit of resources within higher education are noted and the possible implications for assessment practice considered. There is a tension between low-cost and high-quality assessments, yet assessment appears to drive the students' agenda and requires careful thought if the programme design is to lead to high-quality learning outcomes. A theoretical framework is presented with the purpose of developing an assessment strategy which will enhance the quality of learning by the student. A case study of an introductory accounting module is described and issues of teaching, learning and assessment are explored. A message of hope is signalled; it may be possible to foster deep learning through assessments which engage the student actively with the subject, despite the apparent constraints acting upon academics.     

Introducing a Learning Portfolio in an Undergraduate Financial Accounting Course

This paper evaluates changes made to the internal assessment component of a third year financial accounting course at a university in New Zealand. A learning portfolio was designed to supplement existing coursework. The aim was to engender in students a deep rather than a surface approach to learning. As a record of the students' learning, the learning portfolio was an attempt to produce an innovative development in the assessment of what was a traditionally taught financial accounting course. Within their learning portfolios, students were required to complete a number of tasks, each aimed at improving critical thinking skills and creativity. Students were also required to maintain a personal or reflective section aimed at personalising and deepening the quality of their learning.     

美国混合合并反垄断法规制研究

关于混合合并的问题,美国在不同历史时期的态度是不同的,甚至是互相矛盾的。因此,美国的混合合并经历了合法—非法—基本上合法的一个过程。在这个过程中,尤其是美国视混合合并为非法的时期内,通过一系列的具体案件,美国混合合并理论得到了蓬勃发展。我国应当借鉴美国的经验,在反垄断法的实施过程中来具体分析混合合并行为,从而促进我国反垄断法的发展。     

对岩巷大断面如何实现快速掘进的研究

现阶段,我国煤炭开采主要都是地下开采,具有很大的巷道掘进和井巷支护工程量,所以采煤速度直接受到掘进速度的影响。因为巷道掘进工程中技术要求高质量,其严谨性对技术要求更甚,使得掘进的进度即受到设备科技含量的影响,又因为其过程相当严谨,技术要求特别过硬,也很深地拖慢工程进度。据此,牢牢掌握国际领先的采煤技术水平和高效合理的管理制度,推进巷道掘进速度尤其是工效和质量的提高,是助推采掘关系平稳较快提升,煤炭工业可持续发展并强有力提高的上上之策。     

Oligopoly and Merger: A Simple Classroom Game

Professor Miller describes a game which has been used in intermediate price theory courses as well as in introductory classes. Two versions are presented—a duopoly and a six-firm market, both with undifferentiated product and a known market demand schedule. Students are also asked to make a monopoly of the six firms by forming a trust or holding company. Miller contends that the game is more stimulating than lectures aud suspects that it will result in longer retention.     

改进的YOLOv3-Tiny网络在风机叶片损伤检测中的应用

为了解决YOLOv3-Tiny对无人机采集的风机叶片图像损伤检测精度不高的问题,提出一种基于深度学习的风机叶片图像损伤检测方法。首先提出一种跨越式特征联合网络结构,由卷积层和拼接层构成,将不同深度的特征信息进行融合再学习,提取目标多层级特征信息;其次引入Inception模块结构,其中4个平行通道的多个卷积核对输入的特征图进行组合和压缩,在减少网络的学习参数的同时更好地表征图像特征信息,提高小目标的检测精度。实验表明,改进后算法的检测精度提高了2.69%,在自制的数据集中mAP可以达到88.58%,并且模型的参数缩小了4倍。因此,改进的方法比传统的YOLOv3-Tiny网络具有更好的检测效果。研究结果可为基于图像的损伤检测和风机叶片损伤智能识别提供参考。