One-way nesting

Appendix A One-Way Nested Global Regional Model Based on CHASER and WRF/Chem... 

We are now also developing a one-way nested global-regional air quality forecasting (AQF) model system with full chemistry based on the CHASER (Sudo et al. 2002a) and WRF/Chem (Grell et al. 2005). Here, description and evaluation of model system are briefly given. 

The air quality directive of the European commission demands maps on concentrations and exceedances in different detail. For this purpose numerical models can be used. Some model systems are already adjusted to deliver the corresponding maps. For instance, the model system M-SYS consists of three mesoscale and one microscale model areas and applies one-way-nesting for meteorology and chemistry (Trukenmiiller et al. 2004). 

In Norway, the non-hydrostatic MM5 model (Grell et al., 1994 [234]) is nested with the HIRLAM NWP model (Berge et al., 2002 [58]). The latter model is operated on a 10 km horizontal resolution for North-Western Europe. A domain with a resolution of 3 km has been set up for the region around the city of Oslo in which MM5 is one-way nested with HIRLAM. A two-way nesting takes place between the 3 km resolution... 

One way to handle a curved calibration line is to fit the line to a power series. A cubic equation (y = a + bx + cx + dx ) is usually sufficient to fit a case such as Figure 21-1. (In any event, since there are only six known points, you couldn t use a polynomial with more than five adjustable parameters.) You can use either LI NEST or the Solver to obtain the coefficients of the power series. Figure 21-2 shows a spreadsheet in which LI NEST is used to find the regression coefficients for the equation Rdg = a + bx ppm + c x (ppm) + dx (ppm) ... 

One way to test an ordered mixture is to pass the blend through a nest of sieves and assay each particle size fraction. The lesser the variation in potency across the cuts, the better the ordered mix. Note that this test is highly dependent upon how much energy goes into the sieving process. Shaking the sieves by hand would be expected to produce different results than using an ultrasonic method. 

In general the IF-THEN-ELSE conditional statement form is used, combined with the inequality and/or possibilities as found in the HELP. This can involve a switching from one equation to another within this statement. Another way is to use flags or constants that take values of 0 or 1 and are multiplied by terms in the equations to achieve the desired results. The programs RUN and RELUY contain such programming. As shown in RUN, nesting of multiple IF statements is possible ... 

We remark that, in this formulation, we have collected into a single set of one-electron operators all the interaction operators we have defined in the preceding section, and, in parallel, we have put in the qk set both the apparent charges related to the electrons and nuclei of M. This is an apparent simplification as all the operators are indeed present. It is interesting here to note that this nesting of the electrostatic problem in the QM framework is performed in a similar way in all continuum QM solvation codes. 

The structures of boranes can be grouped into several classifications. If the structure contains a complete polyhedron of boron atoms, it is referred to as a closo borane (closo comes from a Greek word meaning closed ). If the structure has one boron atom missing from a comer of the polyhedron, the structure is referred to as a nido borane (nido comes from a Latin word for nest ). In this type of structure, a polyhedron having n comers has (n - 1) comers that are occupied by boron atoms. A borane in which two comers are unoccupied is referred to as an arachno structure (arachno comes from a Greek word for web ). Other types of boranes have structures that are classified in different ways, but they are less numerous and will not be described. 

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