Filter-bank based multi-carrier systems have recently attracted lots of interest as a promising approach for the next generation wireless communication systems. Due to high complexity and long symbol duration, however, these systems need to evolve in a new multi-carrier technique, universal-filtered multi-carrier (UFMC). In conventional UFMC systems, a fixed size of resource block (RB) reduces the flexibility of spectrum utilization and leads to high computational complexity. This problem highlights the need for RB size control that will efficiently allocate frequency resource to satisfy users' resource demand. In this paper, we propose a generalized UFMC system for uplink scenario. First, we analyze the impact of RB size on the UFMC spectrum utilization and complexity. Then, we observe the effect of filter length on symbol error rate (SER). Based on this observation, the proposed UFMC system controls RB size and filter length according to users' demand. Finally, we demonstrate that the proposed system tremendously improves throughput per sub-carrier without SER performance degradation.