Push-Pull Block Puzzles are Hard

This paper proves that push-pull block puzzles in 3D are PSPACE-complete to solve, and push-pull block puzzles in 2D with thin walls are NP-hard to solve, settling an open question by Zubaran and Ritt. Push-pull block puzzles are a type of recreational motion planning problem, similar to Sokoban, that involve moving a `robot' on a square grid with $1 \times 1$ obstacles. The obstacles cannot be traversed by the robot, but some can be pushed and pulled by the robot into adjacent squares. Thin walls prevent movement between two adjacent squares. This work follows in a long line of algorithms and complexity work on similar problems. The 2D push-pull block puzzle shows up in the video games Pukoban as well as The Legend of Zelda: A Link to the Past, giving another proof of hardness for the latter. This variant of block-pushing puzzles is of particular interest because of its connections to reversibility, since any action (e.g., push or pull) can be inverted by another valid action (e.g., pull or push).Comment: Full version of CIAC 2017 paper. 17 page

Investigation of Variable-Glide Parafoils

This project investigated the loading changes experienced by a Jalbert parafoil during a flare deflection maneuver, and 3-D representations of these stages were generated using CAD software. Wind tunnel testing at various angles of attack resulted in coefficient of lift relationships between the stages. Compared to baseline deflection at a constant angle of attack, the partial deflection had a 0.102 lift coefficient increase, the full deflection 0.477, and the flare 0.120

Determination of the effect of brand and product identification on consumer palatability ratings of ground beef patties

Citation: Wilfong, A. K., McKillip, K. V., Gonzalez, J. M., Houser, T. A., Unruh, J. A., Boyle, E. A. E., & O'Quinn, T. G. (2016). Determination of the effect of brand and product identification on consumer palatability ratings of ground beef patties. Journal of Animal Science, 94(11), 4943-4958. doi:10.2527/jas2016-0894The objective of this study was to determine the effect of brand and product identification on consumer palatability ratings of ground beef patties. Six treatments were used in the study: 90/10 Certified Angus Beef (CAB) ground sirloin, 90/10 ground beef, 80/20 CAB ground chuck, 80/20 ground chuck, 80/20 ground beef, and 73/27 CAB ground beef. Ground beef was processed into 151.2-g patties using a patty former with 2 consecutively formed patties assigned to blind consumer testing and the following 2 assigned to informed testing. Following cooking to 74 degrees C, patties were cut into quarters and served to consumers. Consumers (n = 112) evaluated samples in 2 rounds for tenderness, juiciness, flavor liking, texture liking, and overall liking. Each trait was also rated as either acceptable or unacceptable. In the first round of testing, samples were blind evaluated, with no information about the treatments provided to consumers, but in the second round, product type and brand were disclosed prior to sample evaluation. Additionally, texture profile and shear force analyses were performed on patties from each treatment. Few differences were observed for palatability traits during blind consumer testing; however, during informed testing, 90/10 CAB ground sirloin was rated greatest (P < 0.05) for all palatability traits other than juiciness. Also, 90/10 CAB ground sirloin had increased (P < 0.05; (consumer informed score -consumer blind score)/consumer blind score) ratings for tenderness (17.4%), juiciness (36.5%), flavor liking (23.3%), texture liking (18.2%), and overall liking (24.7%) due to brand disclosure. Increased (P < 0.05) ratings were found for CAB products for multiple traits due to treatment disclosure, whereas the only non-CAB-branded product that received increased (P < 0.05) ratings during informed testing was 90/10 ground beef for tenderness and juiciness. Texture results indicated that decreased fat level increased hardness, cohesiveness, gumminess, and chewiness. These results indicate that when sampling ground beef without brand and product information, few consumers find differences in eating quality among ground beef treatments; however, when consumers are aware of the brand, fat level, and subprimal blend prior to sampling, these factors have a large impact on consumer eating satisfaction

The effect of branding on consumer palatability ratings of beef strip loin steaks

Citation: Wilfong, A. K., McKillip, K. V., Gonzalez, J. M., Houser, T. A., Unruh, J. A., Boyle, E. A. E., & O'Quinn, T. G. (2016). The effect of branding on consumer palatability ratings of beef strip loin steaks. Journal of Animal Science, 94(11), 4930-4942. doi:10.2527/jas2016-0893The objective of this study was to determine the influence of knowing the brand or USDA grade on consumer palatability ratings of beef strip loin steaks. Strip loins were selected to represent 5 USDA grades and brands, USDA Select, Choice, Prime, Certified Angus Beef (CAB; upper 2/3 Choice), and Select, from carcasses of cattle classified as Angus on the basis of phenotype. After 21 d of aging, 2.5-cmthick steaks were cut, consecutively cut steaks were paired for consumer evaluation. Consumer panelists (n = 112) evaluated samples for tenderness, juiciness, flavor liking, and overall liking. Additionally, consumers rated each palatability trait as either acceptable or unacceptable. Samples were fed in 2 rounds on the same day: blind and informed testing. In the first round, blind testing, consumers were served 1 sample from each treatment, with no product information provided. In the second round, consumers were informed of the brand or quality grade prior to sampling. During blind testing, CAB rated similar (P > 0.05) to Choice for all palatability traits; however, CAB rated greater P 0.05) for all traits when tested blind, but Angus Select was rated greater (P 0.05) when brand was disclosed. Brand knowledge increased (P 0.05) in the percentage of Choice and Select samples rated as acceptable for all palatability traits. These data indicate that Prime, CAB, and Angus Select steaks receive an increase in consumer palatability perception, or "brand lift," which does not occur for Choice and Select beef

Palatability of Ground Beef Increases When Brand Is Disclosed in Consumer Testing

Of the beef products on the market, ground beef is one of the least expensive and most universal. Ground beef represents the largest volume of protein served in the foodservice industry, at 64%, and is the most popular beef item for consumers when preparing meals in their home (NCBA, 2012). To date, little research has evaluated ground beef palatability despite representing a large sector of the beef market. All ground beef is not the same to consumers. Ground beef from branded beef programs, higher lean points, and primal-specific blends are traditionally sold at retail for higher prices. Branding is used to indicate an increased quality level associated with the product, and encourages consumers to pay a premium in order to receive a superior product (Grunert et al., 2004). Certain branding strategies can influence consumers’ purchasing decisions even if they have not previously tasted the product (Levin and Gaeth, 1988). There is no conclusive evidence of how ground beef palatability changes with fat levels, although some studies have indicated products with higher fat levels are perceived to be more juicy (Myers et al., 2012). It is common for meat product studies to evaluate palatability differences in products through blind testing; however, consumers do not purchase and consume meat without being exposed to information about the product. Therefore, the objective of this study was to determine the effect of brand and product identification on consumer palatability ratings of ground beef patties

The Effect of Enhancement on Trained Panel Beef Palatability Scores Is Dependent Upon USDA Quality Grade

Quality grades are used to determine beef value. The U.S. Department of Agriculture grading system categorizes beef into levels of eating satisfaction with the highest being Prime and decreases until reaching the Canner quality grade. Currently the premium of Prime graded carcasses over Select is $16.73 (USDA, 2015). Traditionally, USDA Select cuts are known to have lower palatability ratings for juiciness, tenderness, and overall liking. Select steaks also fail to meet consumer eating expectations more than 33% of the time (Corbin, 2015). This failure rate represents a large cost for the industry. Product enhancement utilizing a water, salt, and phosphate solution is commonly used in the pork and poultry industries to increase product eating satisfaction. This technology offers an opportunity for the beef industry to improve palatability as well. Previous research has shown enhancing beef results in a higher juiciness, tenderness, and overall liking ratings by consumers and trained panelists (Pietrasik and Janz, 2009). Previous research has shown enhancing Select cuts results in products that rate similar to Prime (Woolley, 2015). To date, it is unknown if enhancement of higher quality beef (Choice and Prime) results in the same increase in palatability observed in lower quality cuts. Therefore, the objective of this study was to determine the effect of enhancement on trained panel beef palatability scores of strip loins of three quality grades when cooked to three degrees of doneness

Pressed Juice Percentage Can Accurately Sort Beef into Categories of Predicted Juiciness

There are three main factors that contribute to meat palatability: tenderness, juiciness, and flavor (Bratzler, 1971). These three individual factors all play a role in the overall palatability perceived by a consumer. If a product fails for juiciness, there is a greater chance that it will fail in overall acceptability (Emerson et. al, 2013). In the past, research has established a method of segregating steaks based on tenderness acceptability. Researchers have been able to institute thresholds to be able to accurately explain at what shear force a steak will be rated tender by consumers. Similar methods have not been evaluated for juiciness until very recently when Woolley (2014) developed a method to objectively quantify beef juiciness. The method that was created included calculating the percentage of moisture loss from each sample after being compressed. From this work, thresholds for juiciness acceptability were established using loigistic regression; however, additional research is needed to verify these established thresholds. Therefore, the objective of this study was to determine the accuracy of previously established threshold values by testing consumer juiciness ratings for beef steaks in relation to objective juiciness measures

Does Knowing Brand or USDA Grade of Beef Strip Steaks Affect Palatability for Consumers?

In consumers’ eyes, not all beef is considered equal. In addition to USDA quality grades, close to 150 branded beef programs are approved for the segregation and marketing of beef products (USDA, 2015). This large number of product categories allows consumers to have a choice in the products they purchase. Blind sensory panel testing of beef, where consumers are not shown the brand or information about a product, has been used for many years. While important to determine palatability characteristics of beef when evaluated blind, consumers do not select, purchase, and consume beef without additional product information. Evidence suggests that branding and product labeling has an influence on consumers’ decisions before having firsthand experience of the product (Levin and Gaeth, 1988). Branding products allows pieces of information to be used to form quality expectations (Steenkamp and vanTrijp, 1996) and can encourage consumers to pay a premium for the increased quality associated with a brand (Grunert et al., 2004). Moreover, previous research suggests that consumers perceive a product differently when brand information is disclosed (Allison and Uhl, 1964). Numerous studies have evaluated the economic impact of beef branding; however, no research has focused on the effect of branding on consumer perception of beef eating quality. Therefore, our objective was to determine how consumer palatability ratings of beef strip loin steaks are affected when products are identified with a brand or USDA grade