Environmental Studies of Monterey Bay and Central California Coastal Zone. First half-year of operation, July 1970-February 1971

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Enhanced Operation of Electricity Distribution Grids Through Smart Metering PLC Network Monitoring, Analysis and Grid Conditioning

Low Voltage (LV) electricity distribution grid operations can be improved through a combination of new smart metering systems' capabilities based on real time Power Line Communications (PLC) and LV grid topology mapping. This paper presents two novel contributions. The first one is a new methodology developed for smart metering PLC network monitoring and analysis. It can be used to obtain relevant information from the grid, thus adding value to existing smart metering deployments and facilitating utility operational activities. A second contribution describes grid conditioning used to obtain LV feeder and phase identification of all connected smart electric meters. Real time availability of such information may help utilities with grid planning, fault location and a more accurate point of supply management.

Design, operation and economics of a small-scale hatchery for the larval rearing of sugpo, Penaeus monodon Fab.

One of the major problems in the mass production of sugpo is how to obtain a constant supply of fry. Since ultimately it is the private sector which should produce the sugpo fry to fill the needs of the industry, the Barangay Hatchery Project under the Prawn Program of the Aquaculture Department of SEAFDEC has scaled down the hatchery technology from large tanks to a level which can be adopted by the private sector, especially in the villages, with a minimum of financial and technical inputs. This guide to small-scale hatchery operations is expected to generate more enthusiasm among fish farmers interested in venturing into sugpo culture.

1ps passively mode-locked laser operation of Na, Yb : CaF2 crystal

Diode-pumped passively mode-locked laser operation of Yb3+,Na+:CaF2 single crystal has been demonstrated for the first time. By using a SESAM ( semiconductor saturable mirror), simultaneous transform-limited 1-ps passively mode-locked pulses, with the repetition rate of 183MHz, were obtained under the self-Q-switched envelope induced by the laser medium. The average output power of 360mW was attained at 1047nm for 3.34W of absorbed power at 976nm, and the corresponding pulse peak power arrived at 27kW, indicating the promising application of Yb3+,Na+-codoped CaF2 crystals in achieving ultra-short pulses and high pulse peak power. (c) 2005 Optical Society of America.

Procedures to prevent the occurrence of potentially dangerous situations during the operation of the Mackereth 1-metre mini or short sediment corer

During the 1950s and 1960s, F.J.H. Mackereth developed and published plans for a series of pneumatic samplers for lake sediments. Unfortunately, as the equipment was continually evolving during ensuing research, no user manuals, beyond the original publication, had been produced. Over the last few years there have been a few potentially very serious accidents with the 1-metre corer, which has prompted the authors to carry out a risk assessment. This highlighted two weaknesses in the design and its later developments. They can be corrected simply by checking for screw threads that may have been added to the exhaust port on the mini-corer, and by changing the operating procedure. An A4 nine-page user manual is now available from the authors. A small charge ( pound sterling 10 in 1998) will be made to cover handling costs and postage.