A semiconductor memory device and a method for generating a reference voltage needed for operating the same are disclosed. A brand association platform determines one or more attributes for one or more branded objects associated with at least one user, at least one device associated with the at least one user, or a combination thereof. Through the structure of the present invention it becomes possible to prevent a deterioration in transmission quality in the case that the number of WDM channels is changed. The joint portion is disposed under the seat portion and connected with the seat portion.