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PHIVOLCS Observatory at Mount Hibok-Hibok.. The Philippine Institute of Volcanology and Seismology (PHIVOLCS, Filipino:; Filipino: Surian ng Pilipinas sa Bulkanolohiya at Sismolohiya [2]) is a Philippine national institution dedicated to provide information on the activities of volcanoes, earthquakes, and tsunamis, as well as other specialized information and services primarily for the ...
The PHIVOLCS earthquake intensity scale (PEIS; Filipino: Panukat ng Pagyanig ng Lindol) [1] is a seismic scale used and developed by the Philippine Institute of Volcanology and Seismology (PHIVOLCS) to measure the intensity of earthquakes. It was developed as upon a specific response to the 1990 Luzon earthquake. PHIVOLCS cites seismic scale ...
The list below showing 27 active volcanoes in the Philippines was based on the PHIVOLCS list with some included from the GVP. The number is not definite and depends on someone's definition of "active" or historical time frame. Descriptions under "eruptions" were based on the GVP website.
Query by Example (QBE) is a database query language for relational databases. It was devised by Moshé M. Zloof at IBM Research during the mid-1970s, in parallel to the development of SQL . [ 1 ] It is the first graphical query language, using visual tables where the user would enter commands, example elements and conditions.
The subduction zones that surround most of the archipelago are the source of many of the larger earthquakes that strike the Philippines. This includes both faulting along the plate interfaces and within the subducting slabs. For the Philippine Trench, examples of those on the plate interface are the 1988 M w 7.3 and the 2023 M7.6 events.
A relational database schema is defined as a tuple S = (D, R, h) where D is the domain of atomic values (see relational model for more on the notions of domain and atomic value), R is a finite set of relation names, and h : R → 2 C. a function that associates a header with each relation name in R. (Note that this is a simplification from the ...
The advantages of using a natural key to uniquely identify records in a relation include less disk space usage, the natural key is an attribute that is related to the business or the real world so in most cases, it is already being stored in the relation which saves disk space as compared to creating a new column for storing the surrogate key.
Fifth normal form (5NF), also known as projection–join normal form (PJ/NF), is a level of database normalization designed to remove redundancy in relational databases recording multi-valued facts by isolating semantically related multiple relationships.