Elf: computer automation and error correction for a microwave network analyzer

A microwave measurement system has been developed that combines a personal computer (PC) and an conventional vector network analyzer to yield a full complex-error-corrected automatic network analyzer. The system consists of a Hewlett-Packard HP 8410C network analyzer, an HP 8350B sweep oscillator, and an IBM PC. A program called Elf runs on the PC, performing calibration and measurement algorithms and providing a flexible, menu-oriented user interface. The system, when calibrated, achieves a worst-case measurement error vector of magnitude ≤ 0.02 for transmission and reflection coefficient measurements over the 2-12.4-GHz frequency range and has a measurement speed of three frequency points/s. Elf provides an inexpensive method for upgrading the HP 8410 to achieve the high accuracy of an automatic network analyzer

The SEC's "Fair Value" Standard for Mutual Fund Investment in Restricted Shares and Other Illiquid Securities

Mutual funds generally do not invest in venture capital, private equity, or restricted shares of public companies. Consequently, individuals who desire to invest in such securities are unable to do so through diversified mutual funds. In this paper, we identify public policies and regulations that discourage mutual fund involvement in the markets for illiquid equity. We also present evidence that changes in SEC policy caused mutual funds to retreat from investing in illiquid equity. Under the Investment Company Act of l940, the SEC requires mutual fund boards to determine and report the “fair value” of their investments in restricted shares and other illiquid equity claims. The SEC interprets fair value to mean value in current sale. Under the Investment Company Act, fair value reporting is a “certification” standard that presumes investors rely on the value representations of the fund board and its auditors. We consider whether alternatives to certification and current sale valuation could reduce barriers to mutual fund investment, without exposing individuals who invest in mutual funds to excessive risk or potential manipulation. To assess the effects of public policies, we analyze recent efforts of the SEC to apply the fair-value standard and examine court decisions arising from subsequent litigation. We also analyze the financial economics literature concerning discounts for illiquidity and the implications for valuing restricted shares. The paper concludes with a discussion of policy alternatives, including allowing funds to rely more on “transparency” in lieu of certification and allowing funds more latitude in determining and reporting the values of their illiquid securities.

Puff, an Interactive Microwave Computer Aided Design Program for Personal Computers

We will demonstrate a CAD program designed for the lay out and analysis of microstrip circuits. The program runs on the IBM PC or AT. Circuit elements are selected from a parts list and drawn on the screen using the cursor keys. The analysis may then be performed, directly from the screen drawing. Puff has been used by microwave students in classes at the California Institute of Technology and the University of California at Los Angeles

Health Transfers: An Application of Health-Health Analysis to Assess Food Safety Regulations

The authors apply a Health-Health Analysis to risks associated with harvesting Gulf oysters to evaluate that approach to managing health and safety risks

Diagnosis and treatment of an excess vertical dimension malocclusion

The orthodontic clinician must use a careful differential diagnosis protocol for each patient who seeks his or her care. The diagnosis must analyze all three components of a malocclusion—facial, dental, and skeletal. Each component must be carefully studied and understood so that (1) the proper questions are asked and (2) the correct diagnostic decisions are made so that an effective treatment plan can be developed. Once the treatment plan is finalized, proper forces at appropriate treatment intervals must be utilized. If these concepts are used, most vertically compromised patients can be successfully treated with conventional orthodontics

The study of the drying of Buna S.

A study of the drying of Buna-S in crumb form (designated as GR-S) is presented in which investigations of vacuum and air drying are made. The drying characteristics are presented and the effect of drying on the quality is evaluated. Vacuum drying is investigated using a shelf and a rotary type unit. The individual effects of temperature, vacuum, thickness of crumb layer, and size of crumb particles are studied. Data are correlated by means of drying rate curves. Comparisons of the effects of the variables are made using these curves. Air drying is studied by the use of a shelf unit with air blowing across the crumb. Air drying also is investigated with air directed through the bed of crumb. The variables studied are: temperature, humidity, air velocity, thickness of crumb layer, size of crumb, and shrinkage of the crumb during drying. The results are presented as drying rate curves and comparisons are made showing the effect of variables. A study of the temperature of the rubber during drying is presented showing the trend as the moisture content changes. The quality of the dried rubber is determined by means of an evaluation of the gel content. The gel content is defined as the per cent of the rubber insoluble in benzene. The results of several studies of the effect of temperature on the formation of gel are presented

Reducing pond seepage (1997)

Excessive seepage from farm ponds is a serious problem in several areas of Missouri. Seepage can be caused by many conditions, such as highly permeable soils, continuous sand or gravel seams, highly permeable bedrock and residual rock layer, and in a few areas, sinkhole collapses in the pond pool area. This publication focuses primarily on seepage that results from permeable soils

A Risk Analysis of Carbon Sequestration in Claypan Soil with Conservation Tillage Systems and Nitrogen Fertilizers for Grain Sorghum and Soybean

Replaced with revised version of paper 02/15/06.carbon sequestration, carbon credits, nitrogen, risk, tillage, Crop Production/Industries, Risk and Uncertainty, Q12,