An English-Chinese Broadcasting Dictionary

A thesis presented to the Graduate School at Morehead State University in partial fulfillment of the requirements for the Masters Degree by Liu, Thin-By Leo on November 27, 1980

Interface-state-induced degradation of GIDL current in n-MOSFETsunder hot-carrier stress

The dependence of increase in post-stress gate-induced-drain-leakage (GIDL) current in n-MOSFET's on creation of interface states (ΔDit) during hot-carrier stress with VG = 0.5 VD was investigated. An interface-trap-assisted tunneling conduction mechanism is proposed to account for the increase. The stress method of VG = 0.5 VD can generate a lot of interface traps near the valence band in thermal oxide samples, which is considerably suppressed in nitrided oxide samples. From the linear relationship between increase in post-stress GIDL current and created interface-state density during hot-carrier stress, ΔDit values can be estimated.published_or_final_versio

Influences of processing technique on electrical characteristics of TVS used in communication systems

An improved technique is proposed in fabricating a semiconductor surge protection device which is used in high-speed wideband information transmission systems. In order to increase the surge handling capability of the device, a double p-type diffusion is used. Specifically, in the diffusion step of gallium, SiO2 is used as a mask to obtain a very small base width and to avoid the reduction of carrier lifetime. It is found that this is a very useful way to reduce the on-state voltage drop and therefore the energy dissipation of the device.published_or_final_versio

Randomized trial on fluorides and sealants for fissure caries prevention

To investigate the effectiveness of topical fluorides in preventing fissure caries, we conducted a randomized controlled trial with parallel groups. In total, 501 children (1,539 molars, 3,078 sites), mean age 9.1 years, who had at least one sound permanent first molar with deep fissures or fissures with signs of early caries were recruited. They were randomly allocated among four groups: (1) resin sealant, single placement; (2) 5% NaF varnish, semi-annual application; (3) 38% silver diamine fluoride (SDF) solution, annual application; and (4) placebo control. Follow-up examinations were conducted every 6 months by a masked examiner. After 24 months, 485 children (97%) were examined. Proportions of pit/fissure sites with dentin caries in the sealant, NaF, SDF, and control groups were 1.6%, 2.4%, 2.2%, and 4.6%, respectively. A multi-level logistic regression analysis accounting for the effects of data clustering and confounding factors showed that fissures in any of the three treatment groups had significantly lower risks of carious cavity development into dentin than did controls (p < 0.05). We concluded that placement of resin sealant, semi-annual application of NaF varnish, and annual application of SDF solution are all effective in preventing pit and fissure caries in permanent molars (ClinicalTrials.gov number CT01446107).postprin

Randomized Clinical Trial on Preventing Root Caries among Community-Dwelling Elders

Dental root caries is a common disease among elders. More efforts on preventing this disease are needed. Silver diammine fluoride (SDF) is known to prevent dental caries in primary teeth. However, clinical evidence of its efficacy in preventing root surface caries is limited. This clinical trial aimed to compare the effectiveness of SDF in preventing root caries among elders in a water fluoridated area. A total of 323 elders who had at least 5 teeth with exposed root surfaces and who had self-care ability were randomly allocated into 3 intervention groups: group 1 (placebo control), annual application of tonic water; group 2, annual application of SDF solution; group 3, annual application of SDF solution, immediately followed by potassium iodide (KI) solution. Oral hygiene instructions and fluoride toothpaste were provided to all subjects. Status of dental root surface was assessed every 6 mo by the same independent examiner. After 30 mo, 257 (79.6%) elders were reviewed. The mean numbers of root surface with new caries experience in the control, SDF, and SDF/KI groups were 1.1, 0.4, and 0.5, respectively (analysis of variance, P 0.05). Moreover, elders who had higher visible plaque index scores at 30-mo examination (analysis of covariance, P < 0.001) and those who had higher baseline DMFT scores (analysis of covariance, P = 0.005) developed more new root caries. It is concluded that annual application of SDF or SDF/KI solution is effective in preventing root caries among community-dwelling elders in a fluoridated area (ClinicalTrials.gov NCT02360124).postprin

Effects of chemical composition on humidity sensitivity of Al/BaTiO3/Si structure

Argon-ion-beam sputtering technique has been applied to deposit barium titanate (BaTiO3) films on silicon wafers at room temperature under vacuum, and then Al/BaTiO3/Si structures were fabricated. Results show that the current and capacitance of these devices are sensitive to the change of relative humidity at room temperature, and saturation absorption (response) time as well as humidity sensitivity of the devices depend on the chemical composition of the BaTiO3 films. For higher annealing temperature and longer annealing time, the oxygen composition increases while fixed charge density decreases. These changes result in lower humidity sensitivity and longer response time.© 1995 American Institute of Physics.published_or_final_versio

Rigorous electromagnetic analysis of a microcylindrical axilens with long focal depth and high transverse resolution

We first present nonparaxial designs for a microcylindrical axilens with different long focal depths and rigorously analyze electromagnetic field distributions of the axilens using integral equations and the boundary-element method. Numerical results show that the designed axilenses indeed have the special feature of attaining a long focal depth while keeping high transverse resolution for numerical apertures of 2.4, 2.0, and 1.0. The ratio between the extended focal depth of the designed axilens and the focal depth of the conventional focal lens is 1.41, the corresponding maximal extended focal depth of the axilens can reach 28 μm, and the spot size of the focal beam is ∼10 μm over the focal range. © 2001 Optical Society of America.published_or_final_versio