Unless otherwise defined, all technical and scientific terms used herein shall have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are merely intended to describe the specific embodiments but not intended to constitute any limitation on this application. The terms “including” and “having” and any other variations thereof in the specification, the claims and the brief description of drawings of this application are intended to cover but not exclude other content.

The term “embodiment” described herein means that specific features, structures or characteristics in combination with descriptions of the embodiments may be incorporated in at least one embodiment of this application. The term “embodiment” in various positions in the specification does not necessarily refer to a same embodiment, or an independent or alternative embodiment that is exclusive of other embodiments. Persons skilled in the art explicitly and implicitly understand that the embodiments described herein may combine with another embodiments.

The term “and/or” in this specification is only an associative relationship for describing associated objects, indicating that three relationships may exist. For example, A and/or B may indicate three scenarios: A alone; A and B; and B alone. In addition, a character “/” in this specification generally indicates an “or” relationship between contextually associated objects.

In addition, the terms “first”, “second” and the like in the specification and the claims or the above accompanying drawings of this application are used to distinguish between different objects but not describe a specific sequence, and can explicitly or implicitly include one or more features.