Overview Evaluation of WEF Resources Case Study No. 1 - Taniguchi et. al (2015) analyzed security measures based on the amount of resource, self-production, and diversity of sources of each resource. Diversity for all the three resources is also analyzed using surface water and groundwater for water sources; hydro power, geothermal power, solar, and biomass for energy; and cereals, vegetable, fruit, meat, and fish for food. They find a high diversity of sources of water in the US and the Philippines