• 대한핵의학회:학술대회논문집
• /
• 2004.11a
• /
• pp.396.2-396.2
• /
• 2004

• 대한핵의학회:학술대회논문집
• /
• 2004.11a
• /
• pp.409.2-409.2
• /
• 2004

• 대한핵의학회:학술대회논문집
• /
• 2003.11a
• /
• pp.23.1-23.1
• /
• 2003

• Bulletin of the Korean Mathematical Society
• /
• v.51 no.2
• /
• pp.501-510
• /
• 2014

We characterize hypergeneralized k-projectors (i.e., $A^k=A^{\dag}$). Also, some representation for the Moore-Penrose inverse of a linear combination of hypergeneralized k-projectors is found and the invertibility for some linear combinations of commuting hypergeneralized k-projectors is considered.

• Bulletin of the Korean Mathematical Society
• /
• v.51 no.3
• /
• pp.765-771
• /
• 2014

Necessary and sufficient conditions for the existence of the group inverse of an anti-triangular block matrix in Banach algebras are presented. Using these results, we give the formulae for the generalized Drazin inverse of a block matrix.

• 대한핵의학회:학술대회논문집
• /
• 2001.11a
• /
• pp.27.2-27.2
• /
• 2001

• Journal of the Korean Mathematical Society
• /
• v.43 no.3
• /
• pp.677-690
• /
• 2006

We show that a group of three closure properties including the selectively Pytkeev property coincide on $C_k$(X) for a locally compact X. We also introduce a new game characterization of these properties for such spaces.

• Convergence Security Journal
• /
• v.4 no.3
• /
• pp.83-90
• /
• 2004

Preventive measures and control over cyber terrorism in Korea is a complex problem. Today laws should meet requirements made by modern technologies development, Law enforcement, special services and judicial system cooperation, their efforts coordination and their material security are priority directions, None of the country is able to prevent cyber terror independently and international cooperation in this field is vital. Taking the above into consideration, we propose and inisit that National Intelligence Service(NIS) should share cyber terror data with Police Agency and have top police authority over the cyber terror.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10b
• /
• pp.30-35
• /
• 1993

Simple recurrence relations for calculating completion times of various storage polices (unlimited, intermediate storages(FIS), finite intermediate storages(FIS), no intermediate storage(NIS), zero wait(ZW) for serial multi-product multi-unit processes are suggested. Not only processing times but also transfer times, set-up (clean-up) times of units and set-up times of storages are considered. Optimal scheduling strategies with zero transfer times and zero set-up times had been developed as a mixed integer linear programniing(MILP) formulation for several intermediate storage policies. In this paper those with non-zero transfer times, non-zero set-up times of units and set-up times of storages are newly proposed as a mixed integer nonlinear programming(MINLP) formulation for various storage polices (UIS, NIS, FIS, and ZW). Several examples are tested to evaluate the robustness of this strategy and reasonable computation times.

• Structural Engineering and Mechanics
• /
• v.52 no.6
• /
• pp.1193-1208
• /
• 2014

A simulation of failures on responsible elements is only one form of the extreme structural behavior analysis. By understanding the dynamic behavior in incidental situations, it is possible to make a special structural design from the point of the largest axial force, stress and redundancy. The numerical realization of one such simulation analysis was performed using FEM in this paper. The boundary parameters of transient analysis, such as overall structural damping coefficient, load accelerations, time of load fall and internal forces in the responsible structural elements, were determined on the basis of the dynamic experimental parameters. The structure eigenfrequencies were determined in modal analysis. In the study, the basic incidental models were set. The models were identified by many years of monitoring incidental situations and the most frequent human errors in work with heavy structures. The combined load models of structure are defined in the paper since the incidents simply arise as consequences of cumulative errors and failures. A feature of a combined model is that the single incident causes the next incident (consecutive timing) as well as that other simple dynamic actions are simultaneous. The structure was observed in three typical load positions taken from the crane passport (range-load). The obtained dynamic responses indicate the degree of structural sensitivity depending on the character of incident. The dynamic coefficient KD was adopted as a parameter for the evaluation of structural sensitivity.