1,513 research outputs found
Influential Article Review - Optimisation Methods of Shipments (SOS)
This paper examines logistics. We present insights from a highly influential paper. Here are the highlights from this paper: This research paper is to announce a new policy to all systems which are sensitive to time. In tramp cargo transportation, as an example, the current policy is to select for each ship the cargo mix which contributes more to a gross-profit objective, assuming deterministic cargo transport demand. Since tramp cargo transportation is sensitive to time, where time varies considerably from one alternative ship voyage to another. The new policy considers this objective less profitable than gross-profit-per-day objective, assuming both deterministic and stochastic cargo transport demand. To introduce this new policy, SOS, a suite of decision support systems, is developed to optimise tramp shipping using a stochastic gross-profit-per-day objective. For operational purposes, SOS selects the most profitable cargo mix. This mix is selected because of the higher gross profit it is expected to yield and the less number of days it takes to generate such profit. For long-term planning purposes, SOS uses the optimal gross profit of each ship voyage, created by the system, to allocate fleet units to cargo trade areas, specifying their frequency of calls to maximise fleet annual gross profit. A useful application of this fleet allocation is that the allocated frequency of calls may be considered as representing the demand on services of utilities of ports, canals, and straits, and may be used to assess the competitiveness of these utilities. Utility and logistics planner, via sensitivity and what-if analysis, can determine whether calling at a utility of a trade area is sensitive to changes made to utility dues and staying time, cargo quantities and freight rates, cargo handling rates and charges, and ship speed and fuel consumption. For appraising purposes, SOS includes new ships in the allocation process, in competition with old ones, to find the share each new ship adds to total gross profit each year. SOS then applies the Net Present Value formula to gross profit of each new ship, along with other cash flow and cost of investment. SOS similar systems may be tailored for other means of cargo transport; namely cargo airplanes, trains, and trucks. The impact of SOS on any logistics and supply chain system is that it maintains the shortest possible transportation time owners of transport units can afford. Case studies are brought to demonstrate research findings. For our overseas readers, we then present the insights from this paper in Spanish, French, Portuguese, and German
Fertilizer Facts
This publication provides information on plant nutrients and their effect on plant growth. Fertilizer terms and definitions, sources and forms of common commercial fertilizers, calculating fertilizer rates and cost, and nutrient loss are also explained
Fertilizing Pasture and Hayland
Guide to fertilizing pasture and hayland discusses fertilization for forage production, established grass-legume mixtures, new seedings, and seed production
CONTINUOUS WEIGHTED JUMPING: EFFECTS ON VERTICAL JUMP HEIGHT
High intensity, near maximal exercise is a conditioning activity which can cause neural hyper-stimulation and lead to acute enhanced power production known as post-activation potentiation (PAP). Investigations need to be conducted to better understand the duration and intensity of the conditioning activity and subsequent effects on the fatigue-potentiation relationship. Purpose: To investigate the effect of 30 seconds of continuous vertical jumping while wearing a vest loaded with 30% of body weight on power output as measured with a maximal vertical jump (VJ). Methods: 14 volunteers (8 weight trained males [23.0+2.9 yrs, 79.8+13.8 kg, 179.9+8.6 cm] and 6 weight trained females [23.0+2.9 yrs, 69.9+13.3 kg, 171.6+7.0 cm]) participated in the study. Pre-testing consisted of each participant performing 3 VJs. The highest VJ was recorded as baseline. A weighted vest was then loaded equaling 30% of the individual's body weight; while wearing the weighted vest, participants performed 30 seconds of continuous VJs. Immediately after jumping participants were seated in a chair for 3 minutes; at 3 minutes, they performed a maximal VJ without the weighted vest in the same manner as done during pre-testing. Two additional VJs were repeated at 4 and 5 minutes post weighted jumping. A mixed design ANOVA with repeated measures was performed. Results: Results showed main effects for each of the independent variables tested, gender and jump. The posttest values at all 3 intervals for both males and females were significantly different from the pretest scores (F [3, 36] = 21.74, p < 0.05). Post hoc analysis indicated that the pretest VJ scores (M = 280.1±18.6 cm) decreased significantly at the 3 minute interval (M = 278.1±18.3 cm), followed by a significant increase in height at the 4 minute interval (M = 281.1±18.7 cm), and another increase at the 5 minute interval (M = 283.0±19.2 cm). Males jumped significantly higher than the females across all trials (p<0.05), however there was no significant difference between male and female VJ gain scores between pre-PAP VJ and 3, 4 and 5 minute post weighted exercise VJ. Conclusion: Results suggest that 30 seconds of weighted VJs causes fatigue which decreases VJ at 3 minutes post exercise. However, a PAP effect was seen at 4 and 5 minutes post weighted exercise significantly increasing VJ above pre testing. From a practical perspective, coaches must be aware of the complex nature of the fatigue-potentiation relationship when attempting to elicit a PAP effect in the individual athlete.  Article visualizations
Comparison of Forward and Reverse Wingate Anaerobic Tests: A Brief Technical Note
BACKGROUND: The Wingate anaerobic test (WAT) is traditionally performed in the forward pedaling direction on a cycle ergometer. However, reverse (backward) pedaling during a WAT test may be a novel way to convey meaningful information related to performance and rehabilitation. This study compared peak power measurements between 30-second forward pedaling WAT (FWAT) with a 30-second reverse pedaling WAT (RWAT). METHODS: 10 male and 10 female participants (age 27.6 ± 7.31 yrs, mass 74.9 ± 21.3 kg and height 172.6 ± 10.9 cm) volunteered to participate. Participants performed one FWAT and one RWAT at 7.5% of body mass on a specially modified Monark cycle ergometer. Tests were separated 2 days of rest. Peak power output (PPO), mean power output (MPO), relative PPO (RPPO), relative MPO (RMPO), fatigue index (%FI), and rating of perceived exertion (RPE) were measured. RESULTS: The FWAT power measurements were all significantly greater (p \u3c 0.05) than RWAT power measurements except MPO (p \u3e 0.05); and that RPE was significantly greater (p \u3c 0.05) in FWAT than RWAT. Specifically, FWAT vs. RWAT (M ± SD) are as follows: PPO watts (w) = 731.7 ± 237.1 vs. 529.6 ± 192.2; RPPO w/kg = 10.2 ± 2.3 vs. 7.2 ± 1.6; MPO w = 510.2 ± 162.1 vs. 415.1 ± 146.2; RMPO w/kg = 7.3 ± 1.5 vs. 5.8 ± 1.3; %FI = 49.2 ± 8.7 vs. 37.4 ± 13.7; and RPE = 19.4 ± 1.1 vs. 15.8 ± 1.5. Gender did not impact the relative differences in these relationships. CONCLUSION: Practitioners and clinicians may use this information to begin to understand the power and perceived exertion relationships of forward versus reverse pedaling during a WAT; exercise prescription for rehabilitation and performance may benefit
Electroweak bubbles and sphalerons
We consider non-perturbative solutions of the Weinberg-Salam model at finite
temperature. We employ an effective temperature-dependent potential yielding a
first order phase transition. In the region of the phase transition, there
exist two kinds of static, spherically symmetric solutions: sphalerons and
bubbles. We analyze these solutions as functions of temperature. We consider
the most general spherically symmetric fluctuations about the two solutions and
construct the discrete modes in the region of the phase transition. Sphalerons
and bubbles both possess a single unstable mode. We present simple
approximation formulae for these levels.Comment: 14 pages, plain tex, 9 figures appended as postscript files at the
end of the paper. THU-93/0
COVID-19: Beyond Washing Your Hands and Social Distancing
A pandemic due to the outbreak of the COVID-19 virus was declared as of March 2020. The authors provide perspective towards preventing and/or mitigating the impact of contracting the virus known as COVID-19. The authors posit straightforward strategies that an individual could implement that may decrease the likelihood of developing COVID-19, help lessen the severity of the symptoms related to the COVID-19 and potentially mitigate the transmission of the virus. The authors consider their comments as food for thought and not as professional medical advice. If you believe you have contracted the COVID-19 virus seek the advice of your healthcare provider
Grip Strength and Functional Measures in the Mature Adult: Brief Report II
Grip strength has been shown to be closely linked to body strength in mature aged adults. However what may be of greater importance is the relationship between grip strength and functional movements in aging adults. Purpose: This study examined the relationship between grip strength and functional body movements in mature aged adults. Methods: Female (n=12, age=71.2±3.8 years, mass=66.3±9.2 kg) and male (n=16, age=72.9±4.7 years, mass=85.5±9.4 kg) participants completed functional body movements including: vertical jump (VJ), medicine ball (MB) throws (1.5, 3.0, & 5.0 Kgs), and a stair climb (SC) test. Likewise, all participants performed maximal hand grip (MG) with the Jamar hand grip dynamometer. Pearson correlation coefficients (PCC) were then calculated to determine the relationship between dominant hand MG and the functional body movement scores. Results: PCC’s were as follows: MG-VJ (r=0.62), MG-MB1.5 (r=0.86), MG-MB3.0 (r=0.87), MG-MB5.0 (r=0.91), and MG-SCP (r=0.79). All PCC’s were statistically significant at P\u3c0.01. Conclusions: Within the parameters of this study, MG strength is strongly reflective of functional body movements that require upper and lower body power output. In this regard, assessing grip strength may be beneficial to clinicians interested in assessing functional body movements in aging adults
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