Commonly proposed ocean wave energy converters (OWEC) use inefficient and maintenance demanding intermediate hydraulic and pneumatic systems. We propose a novel rotary direct-drive OWEC that eliminates these intermediate stages. The new device employs a contactless force transmission system (CFTS) comprising a “piston” and a “cylinder” and a ball screw to...
With the development of high performance power electronic and semiconductor technologies, Adjustable Speed Drive (ASD) systems are increasingly applied in residential, commercial and industrial applications. Due to the advantages at higher power ratings, the three-level Neutral-Point-Clamped (NPC) Voltage Source Inverter (VSI) is being employed in industrial and traction applications, static...
Power quality has become an important concern to both electric utilities and
end users due to the increased use of non-linear loads in modem power systems
over the past decade. Nonlinear loads inject harmonics into the power system and
thus may lead to poor power quality and lower power factor....
This dissertation presents a dual-path 2-0 MASH (Multi-stAge-noise -SHaping) ADC with two verified digital corrections of DAC mismatch error and quantization noise leakage. By using these two techniques, the requirements for the analog circuits are greatly relaxed. The dual-path structure generates two outputs, one only composed of conversion errors, the...
The study of the infra-specific ranks (i.e., subspecies and variety) can be considered
the study of the process of speciation. Astragalus lentiginosus Douglas ex Hooker
(Fabaceae) is the most taxon rich species in the U.S. flora currently including 40
taxonomic varieties. These varieties were described using traditional taxonomic
methods primarily...
Despite recent efforts to improve site safety, construction still accounts for a disproportionate injury and illness rate. According to the 2007 injury and illness data released by the National Safety Council, the construction industry has a fatality and disabling injury rate that is approximately three times higher than the all-industry...
Taiwan has undergone significant social change, particularly in the last forty years, due to economic and industrial growth. Career development intervention is increasingly urgent in helping students face upcoming challenges. This study investigates the implementation and perceived helpfulness of career development interventions in Taiwanese comprehensive high schools. A total of...
Substance abuse is a prevalent occurrence among adolescents. A review of the
literature revealed that adolescent substance abuse has a strong connection to their
academic performance. School counselors address adolescents' academic and
personal/social needs by providing services through prevention education, responsive
services, and collaboration with community members. Yet, there is...
Suicide is currently the third leading cause of death for adolescents ages 15- 24. While much attention has been given to this topic, no research has examined what specific information is being taught to pre-service school counselors. The purpose of this descriptive study was to evaluate the pre-service suicide prevention...
This thesis proposes a novel fully digital technique for the estimation and correction of the DAC error in multi-bit delta sigma ADCs. The structure of the DAC error is indicated through a simple model for unit-element based DACs. The impact of the DAC error on the performance of ADC is...