Terahertz near-field enhancement in narrow rectangular apertures on metal film.

We report huge field accumulations in rectangular aperture arrays on thin metal film by using shape resonance in THz frequency region. A huge far-field transmission enhancement is observed in samples of various widths ranging from 10 mum to 1.8 mum which correspond to only an order of lambda/100. Theoretical calculations based on vector diffraction theory indicates 230 times near-field enhancement in case of the 1.8 mum wide rectangular aperture. Transmission measurement through the single rectangular aperture shows that the shape resonance, not the periodicity, is mainly responsible for the transmission enhancement and the corresponding field enhancement.

Study on a method to improve simultaneously vital statistics and family planning among maternity cases.

PIP: In order to develop a public health program in Korea that would simultaneously improve the reporting of vital health statistics and spread the use of family planning, simple hygenic delivery kits with accompanying family planning information were distributed to expectant mothers in Kimchun city and the surrounding rural district of Kumnung Gun. There was a population of 70,000 people in the experimental and control areas during 1966-67. Vital statistic reports and family planning use were compared between areas with the delivery plan and control areas without the kit delivery. Since use of the delivery kits cut down the infant mortality rate, the mothers should be more receptive to family planning in this program. The delivery kit program was found to improve vital statistic reporting and reduce infant mortality. Though more urban mothers than rural mothers wanted to use the kits, more rural deliveries than urban deliveries actually employed the program's kit. The assigning of a vital events reporter in each area shortened the delay between the event and the report and even increased death reporting though it was not part of the program. Vital statistic reporting was more improved by this program in rural than in urban areas. Family planning acceptance in the experimental area was more than 2 times than in the control area. Though the length of the study is too short to accurately determine its effect on maternal health and fertility patterns in Korea, the combining of hygenic delivery kits with family planning information does improve maternal and infant health, increases vital statistic reporting, and aids family planning acceptacne.^ieng