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91.
92.
Peter Brandt 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2007,1(9):393-398
Um Auskunft über die wirtschaftliche Bedeutung von Kaffee, Tee und Kakao zu geben, werden in diesem Mini-Review u.a. aktuelle
Angaben zur weltweiten Produktion dieser drei „Exoten“ gemacht (Menge und Herkunftsl?nder), die jeweiligen Import-Anteile
der Produktionsl?nder nach Deutschland (bzw. in die EU) benannt, der Pro-Kopf-Verbrauch an Kaffee, Tee oder Kakao in Deutschland
mit dem anderer Staaten verglichen und – sofern m?glich – Einblick gegeben in die Entwicklung von weltweitem Angebot und Nachfrage
und die damit verbundene Preisentwicklung in den vergangenen Jahren. 相似文献
93.
94.
95.
We consider a system defined as the product of a finite set of periodic systems on cyclic groups. It is of interest to determine if certain subgroups and unions of subgroups of the state set are reachable from a specified initial state, and in particular to determine the computational complexity of verifying such reachability. These questions are motivated by certain problems that arise in the modelling and control of discrete event systems and certain forms of periodic scheduling. Our main result is that deciding whether or not the union of a certain set of subgroups is reachable or not is NP-complete. 相似文献
96.
Nickel molybdate catalysts used in several different upgrading reactions of coal-derived materials from low-rank Australian coals have been regenerated and their activity assessed using a number of physical and chemical techniques. Regeneration of spent coked catalysts for 20 hours in air at 450°C was sufficient to restore chemical hydrogenation activity to catalyst used for pre-asphaltene, asphaltene and oil upgrading, provided poisoning of the catalyst surface by other impurities, principally chlorine-containing molecules, had not occurred. 相似文献
97.
Currently, two motivators are effecting change in power systems education. First, the industry's transition to a more competitive environment is requiring changes in the content and pedagogy of power systems education. Second, engineering education as a whole is seeking to modify its curriculum to reflect a better balance between science and education in order to better meet the needs of industry. These curricular changes are largely a result of revised Accreditation Board for Engineering and Technology (ABET) accreditation requirements. In response to these changes, new curriculum and analysis tools were developed for a power systems capstone design course. The project integrates market economics and socio-political considerations with transient stability analysis and transmission planning. A power systems analysis package and an economic analysis tool were developed for use with this project. Student evaluations of the course in which the project was implemented indicate that the curriculum successfully addresses a broad range of ABET accreditation criteria. 相似文献
98.
Experimental studies on phase equilibria in the multicomponent system PbO-ZnO-CaO-SiO2-FeO-Fe2O3 in air have been conducted to characterize the phase relations of a complex slag system used in commercial lead oxidation
smelting. The liquidus in the pseudo-ternary section ZnO-“Fe2O3”-(PbO + CaO + SiO2) with the CaO/SiO2 weight ratio of 0.35 and the PbO/(CaO + SiO2) weight ratio of 5.0 has been constructed using results of over 100 high-temperature equilibration and quenching experiments
followed by electron probe X-ray microanalysis. The liquidus in this pseudoternary section contains primary phase fields of
spinel (zinc ferrite) Zn
x
Fe3−x
O4+y
, zincite Zn
u
Fe1−u
O, melilite Pb
v
Ca2−v
Zn
w
Fe1−w
Si2O7, hematite Fe2O3, magneto-plumbite PbFe10O16, and dicalcium silicate Ca2−t
Pb
t
SiO4. The laboratory results are compared with the slags obtained from an industrial reactor. 相似文献
99.
100.
Peter P. Mykytyn Jr. 《AI & Society》1989,3(2):133-141
Expert systems have been concerned with applications dealing with medical diagnosis, mineral exploration, and computer configuration, with some efforts relatively successful in achieving results at least as good as human experts. Today, much is being written about these systems and managerial decision-making activities in organizations and the positive impact that they can have in these situations. However, it appears that expert systems could become somewhat of a panacea for some organizational ailments as research, development, and marketing of them continues at a fast pace. What may be forgotten in this technological thrust is the individual decision maker and his/her unique style of decision making which could affect acceptance and use of these systems. Another important consideration is the attitude people have toward computers and computer systems, which along with decision-making styles could certainly affect expert system effectiveness and ultimate success in organizations. This paper provides a discussion of potential problems that could occur regarding individual decision making and attitudes and their relationships to these systems. 相似文献