Premise Selection and External Provers for HOL4

Learning-assisted automated reasoning has recently gained popularity among the users of Isabelle/HOL, HOL Light, and Mizar. In this paper, we present an add-on to the HOL4 proof assistant and an adaptation of the HOLyHammer system that provides machine learning-based premise selection and automated reasoning also for HOL4. We efficiently record the HOL4 dependencies and extract features from the theorem statements, which form a basis for premise selection. HOLyHammer transforms the HOL4 statements in the various TPTP-ATP proof formats, which are then processed by the ATPs. We discuss the different evaluation settings: ATPs, accessible lemmas, and premise numbers. We measure the performance of HOLyHammer on the HOL4 standard library. The results are combined accordingly and compared with the HOL Light experiments, showing a comparably high quality of predictions. The system directly benefits HOL4 users by automatically finding proofs dependencies that can be reconstructed by Metis

Comparison of Young and Functional Fit Older Adults on Temporal Spatial Gait Parameters

1Paulson, S., 2Gray, M. 1Shippensburg University, Shippensburg, PA; 2University of Arkansas, Fayetteville, AR Gait speed (GS) has been recognized as an integral component of functional independence. Further, step length (SL), cadence (CAD) and the percentage of the gait cycle in spent in stance (%ST) have been associated with risk of falls and mobility disability among older adults. Purpose: This study examined temporal spatial gait variables in young and low and high functionally fit older adults. Methods: Twenty older and 12 younger adults (CON; M±SD = age: 22.3±1.8, height 1.7±0.1 m, mass 66.1±11.8 kg) completed two 20 m habitual walking trials and the fastest time was recorded. Selected gait variables were averaged from the foot strikes across a gait mat. Functional fitness (FF) was assessed using a stair climb test and relative power was used to create the low (LFF; n = 8; M±SD = age: 73.9±6.9, height 1.6±0.2 m, mass 76.6±15.5 kg) and high (HFF; n= 12; M±SD = age: 70.1±4.2, height 1.75±0.1 m, mass 72.1±14.9 kg) functionally fit older adult groups. A one-way ANOVA was used to assess differences between the groups on the dependent variables of gait. Results: The results yielded a statistically significant difference (p \u3c .05) between the groups for GS, SL, and percentage of swing (%SW) and %ST. The LFF group walked significantly slower than both the CON and HFF group but, there was not a difference in speed between the CON and HFF. The LFF group also spent more time in stance, less time in swing, and had a shorter SL than the CON; however, there was not a difference between the LFF and HFF groups on these variables. The HFF group was not different from the CON on GS, SL, %SW or %ST. Conclusions: The findings of this study suggest that as one ages if they maintain a higher level of FF then they do not express the same age-related changes in gait as those with a lower level

Low-speed longitudinal and lateral-directional aerodynamic characteristics of the X-31 configuration

An experimental investigation of a 19 pct. scale model of the X-31 configuration was completed in the Langley 14 x 22 Foot Subsonic Tunnel. This study was performed to determine the static low speed aerodynamic characteristics of the basic configuration over a large range of angle of attack and sideslip and to study the effects of strakes, leading-edge extensions (wing-body strakes), nose booms, speed-brake deployment, and inlet configurations. The ultimate purpose was to optimize the configuration for high angle of attack and maneuvering-flight conditions. The model was tested at angles of attack from -5 to 67 deg and at sideslip angles from -16 to 16 deg for speeds up to 190 knots (dynamic pressure of 120 psf)

Postshutdown cooling requirements of tungsten water-moderated nuclear rocket

Postshutdown cooling requirements of tungsten water moderated nuclear rocket engine

Correlation Between Handgrip Strength and Functional Fitness Among Older Adults

Please refer to the pdf version of the abstract located adjacent to the title

Southwestern Minnesota Farm Business Management Association 2008 Annual Report

Average net farm income was $190,901 in 2008 for the 99 farms included in this annual report of the Southwestern Minnesota Farm Business Management Association. Average earnings decreased by 21$242,267 in 2007 (Figure 1). 2008 ended a steady trend of increasing year-to-year incomes for these farms from 2001 to 2007. Crop farms, with historically high corn and soybean prices, remained very profitable. However, specialized hog farms, which had been very profitable for the past four years, experienced substantial losses. Highlights of association financial results for 2008: Median net farm income was $178,874, slightly lower than the average, indicating that the average was increased by high profits of the most profitable farms. This effect was not as large as previous years, likely because of losses by larger hog operations. • The difference between the most profitable farms and the least profitable continued to increase. The most profitable 20$449,997 while the least profitable lost $-29,476. • Average gross cash income increased by 20$115,999. The average debt-to-asset ratio improved slightly to 39%, down from 40% (Figure 4). • Corn yields were up but soybean yields were down. Corn averaged 172 bushels per acre compared to 162 in 2007. Soybeans yields decreased to 44 bushels from 49 in 2007 (Figure 5). • Both corn and soybean prices received increased by over 50% to $4.51 for corn and$10.83 for soybeans. • The cost to raise an acre of corn (with land rent) increased by 23% while soybean costs increased by 21%. The cost to produce a bushel of corn on cash rented land increased from $2.58 per bushel in 2007 to$2.90 in 2008, while soybean costs per bushel increased from $6.14 to$7.21. • The average specialized hog operation (those with 70% of sales from hogs or pigs) lost over $150,000 in 2008 (Figure 6). All other farm types with enough farms to report averaged net incomes very close to the association average. • Based on rate of return on assets, crop farms (those with 70$1,000,000, were the least profitable based on rate of return on assets. This group earned an average ROA of 7% compared to 14% for farms that grossed between $500,000 and$1,000,000. • With exceptionally high feed prices, no hog or beef enterprise, with the exception of contract growing of hogs (where the contractor provided the feed) covered even direct costs of production. The report provides additional information on profitability, liquidity, and solvency as well as other whole-farm information and detailed information on crop and livestock enterprises. Also reported are whole-farm financial condition and performance by county, sales size class, type of farm, debt-to-asset ratio, and age of operator.Agricultural Finance, Farm Management,

A review of technologies applicable to low-speed flight of high-performance aircraft investigated in the Langley 14- x 22-foot subsonic tunnel

An extensive research program has been underway at the NASA Langley Research Center to define and develop the technologies required for low-speed flight of high-performance aircraft. This 10-year program has placed emphasis on both short takeoff and landing (STOL) and short takeoff and vertical landing (STOVL) operations rather than on regular up and away flight. A series of NASA in-house as well as joint projects have studied various technologies including high lift, vectored thrust, thrust-induced lift, reversed thrust, an alternate method of providing trim and control, and ground effects. These technologies have been investigated on a number of configurations ranging from industry designs for advanced fighter aircraft to generic wing-canard research models. Test conditions have ranged from hover (or static) through transition to wing-borne flight at angles of attack from -5 to 40 deg at representative thrust coefficients