Efficient Algorithm for K-Barrier Coverage Based on Integer Linear Programming

Barrier coverage of wireless sensor networks is an important issue in the detection of intruders who are attempting to cross a region of interest.However,in certain applications,barrier coverage cannot be satisfied after random deployment.In this paper,we study how mobile sensors can be efficiently relocated to achieve k-barrier coverage.In particular,two problems are studied:relocation of sensors with minimum number of mobile sensors and formation of k-barrier coverage with minimum energy cost.These two problems were formulated as 0–1 integer linear programming(ILP).The formulation is computationally intractable because of integrality and complicated constraints.Therefore,we relax the integrality and complicated constraints of the formulation and construct a special model known as RELAX-RSMN with a totally unimodular constraint coefficient matrix to solve the relaxed 0–1 ILP rapidly through linear programming.Theoretical analysis and simulation were performed to verify the effectiveness of our approach.

商用航空发动机构型变更影响的评估方法

民用航空产品技术复杂,产品数据量大,构型变更频繁,其构型变更管理工作面临巨大的挑战。为了限制不受控的、不必要的变更的扩散,构型变更的过程中必须进行变更影响评估来确定最佳变更方案,兼顾降低变更风险和满足产品需求。基于多域矩阵,建立构型变更影响评估模型,通过产品组件将变更选项和产品需求衔接起来,结合相关变更传播预测计算方法,实现了对构型变更影响的评估,并通过商用航空发动机风扇转子及增压级单元体的构型变更验证了该方法的有效性。