A security card is provided in which an ink region 6 bearing image or textural data is printed onto a substrate 4. With the present invention, the abnormal conditions are diagnosed using the sequential diagnosis technique and the Boolean logic between the abnormal symptoms, making it possible to effectively diagnose the abnormal conditions even under masking effects that may be generated between the abnormal symptoms. Programs may also be recorded on a local media server. The nickel powder and the conductive paste containing the same can control heat shrinkage while inhibiting any rapid oxidation and permit the production of a thin, uniform internal electrode for a multilayer ceramic capacitor without being accompanied by any crack formation and delamination during firing.