Open- versus closed-section

Figure 7-29 Open- versus Closed-Section Stiffeners...

The relative efficiency of the two stiffeners is compared principally on the basis of the torsional resistance. The reason for the lower efficiency rating of the sandwich-blade stiffener is its low torsional resistance (and the bending stiffness is not high) and for the high efficiency of the hat stiffener is its high torsional resistance because of the basic open-versus closed-section stiffener issue. Stiffener torsional resistance affects the buckling load of a stiffened panel or shell as shown by Card and Jones [7-3]. 

Direct your Web browser to http //chemistry.brookscole.com/skoogfac/. From the Chapter Resources menu, choose Web Works. Locate the Chapter 36 section, and find the links for microwave digestion systems. Look up information on open-vessel microwave digestion systems versus closed-vessel systems. Summarize the advantages and disadvantages of these two approaches. 

Figure 2. Total sulfur content (wt.% in rock) versus total organic carbon content (TOC) for the marl section above the laminite (squares) and in the upper (open circles) and lower laminite sections (closed circles).

Further, it is observed experimentally that electron-pair bonds are frequently associated with anisotropic, i.e. directed, atomic orbitals. This gives rise to open structures. However, the electrostatic (Madelung) energy associated with ionic crystals favors close packing Therefore largely ionic crystals favor more close-packed, two-sublattice structures such as rock salt versus zinc blende. In the case of two-sublattice structures induced by d electrons, electron-pair bonds are generally prohibited by the metallic or ionic outer s and p electrons that favor close packing. Nevertheless, it will be found in Chapter III, Section II that, if transition element cations are small relative to the anion interstice and simultaneously have Rti RCf electron-pair bonds may be formed below a critical temperature. 

Requirements for controls are based on definition of closed or open system. Under these definitions there isno direct correlation between, for example, using a publicphone line and an open system. Compliance with closed versus open standards is determined by how access rights to the data or documents are established and controlled by the owner(s) of this information. A system is defined as closed if access to the system containing the records or data is under the control of person(s) responsible for the content of the records or data in the system. A system is defined as open if access to the system is not under the control of the person(s) responsible for the content of the records therein. For example, dial-in retrieval over a public phone is closed where the records being accessed are under the control of the persons responsible for their content, whereas storage of records on a third party system is open because access to the records themselves is under the control of the third party. Sections 11.10 and 11.30 of the Final Rule list, respectively, the control measures required for establishing a closed or open system. 

The review and overview of the following sections allow a better appreciation of the common and different properties of the free versus the confined hydrogen atom, including closed versus open boundary confinements, as well as the specific characteristics associated with each conoidal boundary. 

Fig. 5.4 Fuel conversion (open symbols) and thermal power output (closed symbols) versus inlet velocity. Thermal power output is computed for a channel of 1 mm cross-section...

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