Turn-over time

Does the inventory management system optimize inventory turns over time and assure stock rotation ... 

Without very careful design, the fryer tends to hold a higher volume of oil than a conventional fryer of equal capacity. This increases the oil turn over time, causing more rapid oil degradation. 

Rodhe, H. (1978). Budgets and turn-over times of afmospheric sulfur compounds. Atmos. Environ. 12, 671-680. 

The response time is Vk. However, the turn-over time To is hAJk(Mo - Ml) and thus different from the response time. The turnover time depends on the steady state content Mq. If Mq is just a little bit larger than the threshold value, Tq will be very large. 

The Earth s atmosphere is a reservoir of several gases. The gas molecules in this reservoir are continuously exchanged because of the interaction of different sources and sinks. The average time spent in the atmosphere by the molecules of a given gas is called average residence time, or simply residence time. The atmospheric cycle of a material can also be characterized by the turn-over time (t) which can be, in the case of equilibrium (F=R), defined as follows ... 

Sulfate reduction rates in marine shelf sediments commonly lie in the range of 1-100 nmol cm May (Jorgensen 1982). Since the sulfate concentration in the pore water is around 28 mM or 20 pmol cm the turn-over time of the sulfate pool is in the order of 1-50 years. A purely chemical experiment would thus require a month to several years of incubation. This clearly illustrates why a radiotracer technique is required to measure the rate within several hours. In sediment cores from the open eastern equatorial Pacific obtained by the Ocean Drilling Program it has been possible to push the detectability of this radiotracer method to its physical limit by measuring sulfate reduction rates of <0.001 nmol cm d in 9 million year old sediments at 300 m below the seafloor (Parkes et al. 2005). 

Table 7.2 Calculated turn-over times and times of redox cycling before burial in coastal and slope sediments. The dynamic of redox cycling becomes evident by envisaging a complete oxidation - reduction cycle on a 2 - 6 months time scale.

Location Fe/Mn Turn-over time [d] Times cycied before buriai... 

Hgipron, K. M, (197.3). Epidermal "turn-over time A reexami-naiion, Br. J, Dermatol 86, 14-19. 

Depending on the system to model, specific sources and dimensions of uncertainty are more or less relevant. Typically, the quality dimension is less relevant in the SCM context because its measures are difficult to be incorporated in quantitative models. In contrast, quantitative measures are crucial in planning SC operations. Temporal aspects become especially relevant in the logistical context, e.g. when capacities of transport resources are to be planned and estimations about turn-over times are necessary. 

It is now generally accepted that much useful design information can be obtained in the laboratory so long as the fundamental differences between the laboratory and industrial plant scales of operation are fully appreciated. The two hydrodynamic conditions are quite different. For example, liquor paths and turn-over times are much shorter in the smaller vessels. The suspension circuit may only be a few centimetres in a laboratory vessel, whereas it may be 10 m or more in a full-scale plant. If the solution desupersaturates rapidly, very... 

The technique, however, has some limitationa The inner diameter (i.d.) of the feed tube from the sampling site must be >1 mm, because tubes with smaller i.d. have increased flow resistances. Longer residence times of water in the feed tube should be avoided to prevent microbial growth and sample alteration. Thus, if the manifold of Fig. 26-3 is employed, the length of the feed tube should not exceed 40 m with an i.d. of 1 mm. The residence time will then be 5.23 min. which is well below the known microbial turn-over times of amino acids. 

This time is often referred to as the eddy turn-over time of turbirlence. It is interpreted as the time taken by a particle to perform a full rotation within the eddy. 

Macromixing, produced by turbulence, involves different space and time scales. We have already discussed in Chapter 8 the large scale of turbulence, characterized by the integral scale It and the turbulent velocity Wnns. With that is associated the time scale (equation [8.12]) which is referred to as the eddy turn-over time of turbulence as it gives an order of magnitude of the revolution time of an eddy at the large scale of turbulence ... 

Because of the emphasis on modeling accident causation, data collection systems based on the system-induced error approach are likely to modify their data collection strategies over time. Thus, as evidence accumulates that the existing causal categories are inadequate to accoimt for the accidents and near misses that are reported, the data collection philosophy will be modified, and a new accident causation model developed. This, in turn, will be modified on the basis of subsequent evidence. 

The overall rate constant for conversion of the E S complex to products E + P is called the turnover number because it represents the number of substrate molecules the enzyme turns over into product per unit time. A value of about 103 per second is typical. 

For the hydrogen electron, the square of the wave function, tp is directly proportional to the probability of finding the electron at a particular point If ip2 at point A is twice as large as at point B, then we are twice as likely to find the electron at A as at B. Putting it another way, over time the electron will turn up at A twice as often as at B. 

SxxK (3-lactamases are uncoupled SxxK acyl transferases that work as (3-lactam antibiotic hydrolases. They represent a mechanism of defence of great efficiency. On good (3-lactam substrates, their catalytic centres can turn over 1000 times per second. 

One further difference between the tissues should be noted briefly—that of turnover—which holds implications for the nature of the isotopic signal recorded and its interpretation. Bone is constantly resorbed and reformed during life, i.e., it turns over , whereas enamel and dentine do not, although secondary dentine can be later accreted. Enamel and dentine form during a discrete period in the individual s life. This means that carbon isotope dietary signals in bone, for both collagen and apatite, reflect diet integrated over years, whereas those in enamel and dentine increments reflect diet at time of formation. 

Dynamic Changes to Process Conditions. Because of the dynamic nature of chemical processes, conditions change over time as a result of changes in production rates, quality targets, feed compositions, and equipment conditions. This in turn changes how certain process information may be interpreted. Thus, adaptive interpretation ability is often required. 

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