This paper presents an optimization methodology that includes three important components necessary for a systematic approach to naval ship concept design. These are: ▪ An efficient and effective search of design space for non‐dominated designs▪ Well‐defined and quantitative measures of objective attributes▪ An effective format to describe the design space and to present non‐dominated concepts for rational selection by the customer. A Multiple‐Objective Genetic Optimization (MOGO) is used to search design parameter space and identify non‐dominated design concepts based on life cycle cost and mission effectiveness. A non‐dominated frontier and selected generations of feasible designs are used to present results to the customer for selection of preferred alternatives. A naval ship design application is presented.

In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia. At each site, 4 plots of each treatment were planted in a randomized complete block design. The 15 treatments included 5 winter annual grasses [barley (BA), ryegrass (RG), rye (RY), triticale (TR), and wheat (WT)] in monoculture [i.e., no legumes (NO)] or with 1 of 2 winter annual legumes [crimson clover (CC) and hairy vetch (HV)]. After harvesting the winter crops, corn and forage sorghum were planted within the same plots perpendicular to the winter crop plantings. The nutritional composition and the in vitro digestibility of winter and summer crops were determined for fresh and ensiled samples. Growing grasses in mixtures with CC increased forage dry matter (DM) yield (2.84 Mg/ha), but the yield of mixtures with HV (2.47 Mg/ha) was similar to that of grasses grown in monoculture (2.40 Mg/ha). Growing grasses in mixtures with legumes increased the crude protein concentration of the fresh forage from 13.0% to 15.5% for CC and to 17.3% for HV. For neutral detergent fiber (NDF) concentrations, the interaction between grasses and legumes was significant for both fresh and ensiled forages. Growing BA, RY, and TR in mixtures with legumes decreased NDF concentrations, whereas growing RG and WT with legumes did not affect the NDF concentrations of either the fresh or the ensiled forages. Growing grasses in mixtures with legumes decreased the concentration of sugars of fresh forages relative to grasses grown in monoculture. Primarily, this decrease can be attributed to low concentrations of sugars of mixtures with HV (10.5%). Growing grasses in mixtures with legumes reduced the fiber digestibility of both winter crops (75.7% to 72.8% NDF). Growing grasses in mixtures with legumes did not affect estimated DM yield, nutritional composition, or digestibility of the succeeding summer crops. In conclusion, growing grasses in mixtures with legumes as winter forage crops can increase forage estimated DM yields and its nutritional quality in dairy farming sytems.

This paper examines the influence of collision scenario random variables on the extent of predicted damage in ship collisions. Struck and striking ship speed, collision angle, striking ship type and striking ship displacement are treated as independent random variables. Other striking ship characteristics are treated as dependent variables derived from the independent variables based on relationships developed from worldwide ship data. A simplified collision model (SIMCOL) is used to assess the sensitivity of probabilistic damage extent to these variables. SIMCOL applies the scenario variables directly in a time-stepping simultaneous solution of internal (structural) and external (ship) problems vice an uncoupled solution of these problems. During the simultaneous solution SIMCOL also calculates struck ship absorbed energy in the longitudinal and transverse directions. These results are compared to absorbed energy estimated based on uncoupled external dynamics only. The necessity and effectiveness of this approach is examined.Brown, A.J., "Collision Scenarios and Probabilistic Collision Damage", 2nd International Conference on Collision and Grounding,

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Corn silage is a major ingredient of diets for dairy cattle. Environmental factors can affect the yield and composition of corn silage. Drought and heat are two common environmental factors that affect silage yield and quality. Corn silages with low concentrations of dry matter, high concentrations of protein, high concentrations of fiber, and low concentrations of starch indicate that the crop was harvested too early, that abiotic stresses affected the structure of the plant, or a combination of both. Drought stress during vegetative stages does not affect yield and nutritional composition as much as during reproductive stages. High environmental temperatures (>35 °C) can also induce kernel abortion. The effects of abiotic stresses on cell wall composition are less clear. Drought stress would likely increase fiber digestibility, whereas heat stress would decrease fiber digestibility. These statements are somehow contradictory in the sense that drought stress and heat stress likely occur simultaneously. Management practices, such as hybrid selection and planting date, should be considered to avoid silking and early kernel development during season of very high environmental temperatures.