Kaffe在龙芯2E上的移植

为了在龙芯2E处理器上建立稳定的Java运行环境,丰富龙芯平台的上层软件库,以Kaffe这款开源Java虚拟机为移植对象,分析了其运行机制,确定了其代码结构中平台相关的3个主要模块:SysCallMethod、Trampoline和JTT,并结合龙芯2E处理器的特点,给出了相关模块的修改方案.最后用第三方的测试标准对移植后的虚拟机进行了测试,表明了移植的有效性.

Kaffe虚拟机在龙芯2E上的移植研究

Java虚拟机作为Java运行环境的核心，已成为现代计算机平台不可缺少的组成部分。Java虚拟机和平台间的兼容性直接决定了上层Java程序的运行的稳定性。龙芯2E是由中科院计算机研究所自主研发的高性能微处理器。由于采用MIPS指令集，现有Java虚拟机对龙芯的支持并不理想，这极大地限制了龙芯平台的上层应用。 针对这一问题，本文对现有虚拟机进行了分析，选择了移植性较强的Kaffe虚拟机作为移植对象，力求在龙芯2E上建立一个稳定的Java运行环境。以此为目的，本文整理了龙芯2E相关的内容，包括龙芯2E的指令集特点，龙芯下参数传递的方式，龙芯下函数栈的组织等等；研究了Java虚拟机规范中，一般Java虚拟机的体系结构；分析了Kaffe虚拟机的代码结构，确定了移植需要修改的三个主要模块：本地代码调用接口，Trampoline技术和JIT3引擎；给出了移植方案。其中，JIT3引擎作为整个虚拟机的核心，是整个移植工作的重点。本文对其编译过程，寄存器分配策略，Java栈的组织方式，以及标签，常量池等平台相关机制进行了深入的分析。在此基础上，修改了Java栈向本地栈的映射方式，实现了标签机制中平台相关部分的代码，重新描述了寄存器信息并重新实现了本地汇编指令。 针对Java虚拟机调试困难的问题，本文总结了龙芯平台下Kaffe虚拟机的调试方法。在调试过程中发现了Kaffe原有代码中的编码错误，并给出了修改方案。 最后采用第三方的评测工具对移植后的虚拟机进行测试，验证了移植的有效性。

EOQ, JIT and fixed costs in the Ready-mixed concrete industry

The successful implementation of just-in-time (JIT) purchasing policy in many industries has prompted many companies that still use the economic order quantity (EOQ) purchasing policy to ponder if they should switch to the JIT purchasing policy. Despite existing studies that directly compare the costs between the EOQ and JIT purchasing systems, this decision is, however, still difficult to be made, especially when price discount has to be considered. JIT purchasing may not always be successful even though plants that adopted JIT operations have experienced or can take advantage of physical space reduction. Hence, the objective of this study is to expand on a classical EOQ with a price discount model to derive the EOQ–JIT cost indifference point. The objective was tested and achieved through a survey and case study conducted in the ready-mixed concrete industry in Singapore.

A model for comparative analysis of inventory costs of JIT and EOQ purchasing in the ready mixed concrete industry

A model for comparing the inventory costs of purchasing under the economic order quantity (EOQ) system and the just-in-time (JIT) order purchasing system in existing literature concluded that JIT purchasing was virtually always the preferable inventory ordering system especially at high level of annual demand. By expanding the classical EOQ model, this paper shows that it is possible for the EOQ system to be more cost effective than the JIT system once the inventory demand approaches the EOQ-JIT cost indifference point. The case study conducted in the ready-mixed concrete industry in Singapore supported this proposition.

Emvâl-i gayr-i menkule kavanin-i muvakkatası : 1 Teşrinisani 1335 tarihine kadar kaffe-yi tadilât ve müzeyyelâtı muhtevîdir.

Özege, M.S. Eski harflerle,

Mahakim-i nizamiye harç tarifesi : 1 Mayıs 1336 tarihine kadar kaffe-yi tadilât ve müzeyyelâtı muhtevîdir.

Turkish in Arabic script.

Der kaffe und seine stellvertreter.

Mode of access: Internet.