Satisfying Business Problems

Successful requirements engineering is about more than just managing requirements. It's also about the relationship to and management of specifications. Typically, traceability structures capture the relationships between requirements, specifications, and domain statements. Traceability is therefore about more than just the relationships between requirements, stakeholders, and designs. At Praxis, we've started to apply these principles to solving business problems as well as systems-engineering problems. As an example we introduce the staff recruitment process in this article     

Satisfying constraint sets through convex envelopes

In this article, we present a general representation for constraint satisfaction problems with disjunctive relations called cluster constraint systems (CCS). For this representation, we develop a novel and simple approach for solving CCSs using convex envelopes. These envelopes can be used to decompose the feasible space of the CCS through convex approximations. We explore interval reasoning as a case study of CCS. Our experimental results demonstrate that such CCS can be effectively and efficiently solved through convex enveloping with very modest branching requirements in comparison to other generic as well as specialized algorithms for interval reasoning. In fact, convex enveloping solves significantly more cases and more efficiently than other methods used in our test bed.     

满足指定节点约束的路由算法

在MPLS或GMPLS网络中,路由算法常常需考虑节点约束条件(即用户可能指定一条端到端路径所必须经过的一些中途节点)。对链路代价值为整数的有向无回路网络,文章提出了一种伪多项式时间算法,用于计算满足指定节点约束的最小代价路径。对一般有向网络,文中给出了一种计算时间及空间上限可调的启发式算法。仿真实验结果表明,所给的启发式算法在网络规模变大时明显优于已知的算法。     

新的群播路由算法

考虑了费用非对称通信网络上的群播路由问题。首先提出了一种满足带宽约束接近最小成本的启发式算法NEW1-GM算法。该算法以FMPH算法(FastMinimumPathCostHeuristicAlgorithm)为基础,可以有效地降低成本。数值实验表明,这种算法是有效的,且所获得解的总费用几乎总是小于或等于由GTM算法所获得的解的总费用。然后,提出了一种满足延迟约束的DFMPH算法(Delay-ConstrainedFastMinimumPathCostHeuristicAlgorithm)。最后,在NEW1-GM算法和DFMPH算法的基础上提出了一种不仅满足延迟和带宽要求且接近最小成本的启发式算法DGM1算法。NEW1-GM算法和DGM1算法的时间复杂度均与GTM算法相同,为O(p3n2)。     

灵敏度约束的自整定最优比例积分控制器

针对一阶延时(FOPDT)模型,考虑到阶跃负载的干扰,以最小化时间乘绝对误差积分或最大积分增益为目标,利用数值优化运算获取比例积分控制器参数.在过程惯性时间与时滞时间之比的大范围内,通过寻优数值拟合出控制器参数调整公式.最后,用双通道继电器闭环测试获取过程信息,建立近似的一阶延时模型来自动整定控制器参数.仿真结果证明了此方法的有效性.     

一种满足数据时新性的WSN运载路由算法

为满足无线传感器网络应用的数据时新性,综合节点传送数据和移动设备辅助传送数据2种方式的优点,提出一种能量高效的运载路由算法。通过计算移动设备的最优接收数据位置,规划移动设备的路径,降低传感器节点的能量消耗,由此提高网络性能。模拟结果表明,该算法能在保证数据时新性的前提下,较大地减少网络能耗。     

Satisfying DO-178C Structural Coverage Objectives

Structural coverage analysis is an important task for the development of safety-critical systems. In particular, structural coverage analysis is one of the objectives specified in RTCA DO-178C for the airborne software verification process. Structural coverage analysis is normally supported by the tools that collect coverage information in the course of test execution. This paper concerns with the problems and methods of structural coverage collecting in order to specify the required functionality of structural coverage collecting tools, which is necessary to provide their compliance with the DO-178C objectives.     

Satisfying solutions for a possibilistic linear program

A branch and bound scheme is described for tackling a linear program under discrete possibilistic data. We grapple also with the continuous case via recent results on inexact and semiinfinite programming. It is shown that solutions yielded by these techniques are satisfying, i.e. possibly and/or necessarily feasible, and optimal to a great extent. Finally, approaches reported here and elsewhere are appraised in the light of their decision-making philosophies, and some directions for further developments indicated.     

Direct Employee Involvement Quality (DEIQ)

This paper focuses on one aspect of human resource management (HRM) that is important for innovative employee behaviour: direct employee involvement quality (DEIQ). However, research has also shown that employee involvement is often in serious need of improvement. This paper presents evidence from three manufacturing companies in the Netherlands. Semi‐structured interviews were conducted with low‐ and medium‐educated blue‐collar workers, top managers (HRM, production and R&D) and direct supervisors. Using a qualitative approach, we were able to acquire insight into the ‘black‐box’ of well‐known pre‐conditions and contribute by identifying additional dimensions. The research supports various pre‐conditions critical for successful DEIQ including the critical role of the HR function and adequate preparation of direct supervisors. Furthermore, an under‐explored issue is highlighted: the employment relationship.     

Satisfying user preferences in optimised ridesharing services:

Applied Intelligence - Ridesharing services offer on-demand transportation solutions while improving the utilization of the available capacity of the vehicles on the road. Profit, travel time, and...     

一种可靠性驱动的云工作流调度遗传算法

为了解决云环境中工作流调度的可靠性问题,提出了一种基于可靠性驱动信誉度模型的工作流调度遗传算法RDR-GA。算法以工作流执行跨度makespan与可靠性最优化为目标,设计了一种基于时间依赖的可靠性驱动信誉度模型,通过该模型可以有效评估资源可靠性。同时,为了寻找遗传最优解,算法设计了新的遗传进化和评估机制,包括：1)以进化算子对调度解中的任务-资源映射进行遗传进化;2)以两阶段MAX-MIN策略评估并决定调度解的任务执行序列。仿真实验结果表明,满足可靠性驱动的信誉度算法不仅能够以更精确的信誉度改善工作流应用执行可靠性,而且能够以比同类遗传算法更快的收敛速度得到进化更优解。     

一种满足覆盖约束的WSN可靠路由协议

针对无线传感器网络中节点的能耗和部署问题,提出一种满足覆盖约束的有限可靠路由协议。由工作节点和冗余节点构成节点集,将节点剩余能量值作为节点轮换的参考指标,定义节点工作的有限状态机,并引入一种混合可靠性机制,能在避免产生覆盖漏洞的同时,将丢包率控制在允许范围内。仿真结果表明,该协议能延长网络寿命,降低网络整体能耗。     

满足嵌入式实时数据库系统的可预见能力

可预见能力是嵌入式实时数据库系统必须具备的特性，目前还未发现有关的研究报道，我们研制的嵌入式实时数据库系统主要从四个方面提高系统的可预见能力，存取扩展数据，使系统内部控制可见，便于透明地处理系统纠偏；基于功能替代的实时事务模型，它支持方案多选，具有丰富的可预见描述能力，支持事件驱动的主动触发机制，能对系统的瞬时发生作出应急反应，多层次的实时事务调度，能大大提高实时事务对动态实时环境的的应变能力和系统的成功率。     

满足因果约束的多速率单值广义预测控制

针对输入更新频率和输出采样频率均不相同的多速率采样系统,提出一种多速率广义预测控制算法．通过采用在系统周期内根据不同的采样时刻构造扩展模型序列的方法,有效地解决了由于多速率采样而引起的因果约束问题．在此基础上,对算法的闭环稳定性进行了分析,仿真结果证明了算法的有效性．     

满足重构概率约束的更少贝努利观测

在压缩感知(Compressed sensing, CS)中,一些方法统计地提供了给定观测数量下的信号重构概率. 然而,在重构概率有约束的情况下,现有方法不能找到满足约束的观测. 本文以压缩感知中常用的贝努利观测集为研究对象, 基于贝努利观测的特征和序列压缩感知理论获得了满足重构概率约束的观测. 另外,由于所提方法能从获取的过多观测中移除部分冗余观测, 观测结果包含更少的观测数据. 所提方法有三个优点:满足重构概率约束、 包含更少的观测数据以及具有全局收敛的属性. 理论分析和实验结果验证了所提方法的有效性.