Feasibility of a just-in-time inventory in a job-shop environment

The Oscar Mayer Machine Assembly and Parts Supply Assembly Inventory has been experiencing a great increase in holding value in the past years. No more resources are to be allotted to this inventory and the continued increase in holding value creates a situation of dead capital unable to be used elsewhere and unable to be depreciated. This inventory must be reduced and the feasibility of implementing a just-in-time inventory in order to accomplish this is the focus of the paper. The literature indicates that a full JIT implementation is impossible because of the custom engineering manufacturing environment of the inventory. Other more practical considerations such as inventory bloat and long lead times make staying with the present system just as unacceptable. Based on the parts usage and parts repeatability data and the aggregate inventory data, the recommendation is to accept and implement a partial JIT system including the principles of vendor relations, supplier certification, and employee involvement

Interannual variability in North American grassland biomass/productivity detected by SeaWinds scatterometer backscatter

We analyzed 2000–2004 growing-season SeaWinds Ku-band microwave backscatter and MODIS leaf area index (LAI) data over North America. Large anomalies in mid-growing-season mean backscatter and LAI, relative to 5-year mean values, occurred primarily in the western Great Plains; backscatter and LAI anomalies had similar spatial patterns across this region. Backscatter and LAI time series data for three ∼103 km2 regions in the western Great Plains were strongly correlated (r2 ∼ 0.6–0.8), and variability in mid-growing season values was well-correlated with annual precipitation (October through September). The results indicate that SeaWinds backscatter is sensitive to interannual variability in grassland biomass/productivity, and can provide an assessment that is completely independent of optical/near-infrared remote sensing instruments

A summary of microwave remote sensing investigations planned for BOREAS

The Boreal Ecosystem - Atmosphere Study (BOREAS) is a multidisciplinary field and remote sensing study that will be implemented jointly by the United States and Canada. The goal of BOREAS is to obtain an improved understanding of the interactions between the boreal forest biome and the atmosphere in order to clarify their roles in global change. Specific objectives are to improve the understanding of the processes that govern the exchanges of water, energy, heat, carbon, and trace gases between boreal ecosystems and the atmosphere, and to develop and validate remote sensing algorithms for transferring the understanding of these processes from local to regional scales. Two principal field sites, both within Canada, were selected. The northern site is located near Thompson, Manitoba, and the southern site encompasses Prince Albert National Park in Saskatchewan. The growing season in the northern site tends to be limited by growing-degree days while the southern site is limited by soil moisture and fire frequency. Most of the field work will occur at these two sites during 1993 and 1994 as part of six field campaigns. The first of these campaigns is scheduled for August 1993 and will involve instrument installation and an operational shakedown. Three large scale Intensive Field Campaigns (IFC's) are scheduled for 1994, along with two smaller scale Focused Field Campaigns (FFC's). The first 1994 campaign will be an FFC designed to capture the biome under completely frozen conditions during the winter. The second FFC and the first IFC are scheduled to capture the spring thaw period. Another IFC will take place in the summer during a period of maximum water stress. Finally, the third FFC will be scheduled to capture the collapse into senescence during the fall

Using the space-borne NASA scatterometer (NSCAT) to determine the frozen and thawed seasons

We hypothesize that the strong sensitivity of radar backscatter to surface dielectric properties, and hence to the phase (solid or liquid) of any water near the surface should make space-borne radar observations a powerful tool for large-scale spatial monitoring of the freeze/thaw state of the land surface, and thus ecosystem growing season length. We analyzed the NASA scatterometer (NSCAT) backscatter from September 1996 to June 1997, along with temperature and snow depth observations and ecosystem modeling, for three BOREAS sites in central Canada. Because of its short wavelength (2.14 cm), NSCAT was sensitive to canopy and surface water. NSCAT had 25 km spatial resolution and approximately twice-daily temporal coverage at the BOREAS latitude. At the northern site the NSCAT signal showed strong seasonality, with backscatter around −8 dB in winter and −12 dB in early summer and fall. The NSCAT signal for the southern sites had less seasonality. At all three sites there was a strong decrease in backscatter during spring thaw (4–6 dB). At the southern deciduous site, NSCAT backscatter rose from −11 to −9.2 dB during spring leaf-out. All sites showed 1–2 dB backscatter shifts corresponding to changes in landscape water state coincident with brief midwinter thaws, snowfall, and extreme cold (Tmax\u3c−25°C). Freeze/thaw detection algorithms developed for other radar instruments gave reasonable results for the northern site but were not successful at the two southern sites. We developed a change detection algorithm based on first differences of 5-day smoothed NSCAT backscatter measurements. This algorithm had some success in identifying the arrival of freezing conditions in the autumn and the beginning of thaw in the spring. Changes in surface freeze/thaw state generally coincided with the arrival and departure of the seasonal snow cover and with simulated shifts in the directions of net carbon exchange at each of the study sites

Divergence in seasonal hydrology across northern Eurasia: Emerging trends and water cycle linkages

Discharge from large Eurasia rivers increased during the 20th century, yet much remains unknown regarding details of this increasing freshwater flux. Here, for the three largest Eurasian basins (the Ob, Yenisei, and Lena) we examine the nature of annual and seasonal discharge trends by investigating the flow changes along with those for precipitation, snow depth, and snow water equivalent. On the basis of a multiperiod trend analysis and examination of station data, we propose two characteristic regimes to explain the long‐term discharge increase from these large Eurasian rivers. Over the early decades from approximately 1936 to 1965, annual precipitation correlates well with annual discharge, and positive discharge trends are concurrent with summer/fall discharge increases. The latter decades were marked by a divergence between winter/spring flows, which increased, amid summer/fall discharge declines. A comparison of cold season precipitation (CSP) and spring discharge trends across subbasins of the Ob, Yenisei, and Lena shows limited agreement with one precipitation data set but good agreement (R2 \u3e 0.90) when a second is used. While natural variability in the Arctic system tends to mask these emerging trends, spatial and temporal changes can generally be characterized by increased solid precipitation, primarily to the north, along with a drier hydrography during the warm season

The Influence of Geometry Variation and Heat Sink Angle on its Thermal Performance

Light-emitting diodes (LEDs) are becoming substantially more popular than traditional lighting methods. LED lights are high power density devices that need thermal management systems to extend their useful life. This paper presents an experimental study on radial aluminum heat sink fabricated by metal additive manufacturing process operating under natural convection conditions. New design considerations such as adapting the middle fin, fin height gradient towards the centre of the heat sink, along with fin perforations and a spiral cut out of the central pillar have been used to improve the thermal performance of the heat sink. For different fin numbers, the effect of the orientation on the natural heat transfer was studied. The performance of three different geometries with 6, 8 and 10 long fins (6LF, 8LF and 10LF) were evaluated under three different heat flux conditions (471.57W/m2, 943.14W/m2 and 1257.52W/m2) for 10 different orientation angles from 0 to 90. It was found that the orientation has a weaker effect on high-density heat sinks than on low ones due to the hindered convective fluid flow by the overlapping of thermal boundary layers. The Rayleigh number was showed to have a significant effect on heat transfer and this effect was the most prominent for the 6LF heat sink. The overall Nusselt number correlations to predict the heat transfer as a function of the Rayleigh number for the 6LF, 8LF and 10LF heat sinks are 0.2748Ra^0.3425, 0.3868Ra^0.2747 and 0.3317Ra^0.2708, respectively

Unmanned Vertical Lift for Medical Equipment Distribution

This report provides a comprehensive methodical design of an autonomous flying vehicle, for the purpose of transporting medical supplies. Current medical supply transportation infrastructure lacks the ability to adequately service the rapidly growing industry, especially in times of crisis. To help solve this issue, this report details the design of an unmanned drone which can carry a fifty-kilogram payload for fifty kilometers, in twenty-eight minutes. The drone is also capable of transporting a fifty-kilogram payload for two hundred kilometers in seventy-five minutes or less, all while flying at an altitude of up to one thousand meters. Since the medical field often involves emergencies, the drone is designed to load and unload the payload quickly. Methods of analysis include the DMAIC approach, which was implored in order to proliferate the design process. TOPSIS analysis and flow simulation were analysis methods used as well. The final design is a VTOL craft, with a rotating wing design which allows the craft to take off and hover like a helicopter, but also fly horizontally like a traditional plane. The final weight of the craft is 198.56 kilograms, excluding the payload. The aircraft is electric and powered via lithium sulfur batteries. The aircraft carries the payload on the underside of the fuselage, via a system of brackets which raise and lower between the landing gear to drop off this payload at its destination autonomously. This design has the potential to completely change the way medical supplies is transported, and in turn increase efficiency in the medical field. While it is still just a design, this craft can be built, refined, and used in the real world with further optimization

The effect of glycogen depletion on responses of interleukin-1β, interleukin-6, and interleukin-10 to maximal exercise

The purpose of this study was to investigate the influence of glycogen stores on the maximal responses of IL-1β, IL-6, and IL-10 to a discontinuous, progressive cycle ergometry test. Eight trained cyclists completed two progressive maximal cycle ergometry tests (5 min stages with 5 min recovery), one normally fed and one following glycogen-depletion (2-h at 60-65% VO2max). Percent changes in circulating IL-1β, IL-6, and IL-10 were measured during exercise and recovery and peak changes were compared. IL-6 showed a trend towards significant interaction effect of exercise time and trial condition (p = 0.054) in both trials, but there were no significant differences among percent changes in IL-1β or IL-10. Glycogenreduction appeared to cause all cytokines to peak earlier, but the trend was not significant