Systems elements external

The criteria for classifying responses as important or unimportant are seldom based solely on the system itself, but rather are usually based on elements external to the system. For example, in the wine-making process, is percent alcohol an important or... 

A module just described is a fixed module in which the membrane elements are stationary. A radical departure from the conventional mode of R.O. systems operations is the rotary system wherein externally wound membrane elements clustered around a central shaft are rotated in a stationary pressure vessel filled with pressurized feed stock. Here the separated permeate is replaced by an equivalent volume of fresh feed stock under a constant head. The basic rotary concept is depicted in Fig. 3. 

R.O. systems utilizing externally wound tubular membrane element in modular assemblies have been used in the desalination of brackish and sea waters, the treatment and/or concentration of industrial waste waters, the separation/concentration of fluid food, pharmaceuticals and chemical solutions, and the manufacture of water purifiers for domestic use. Generally, externally wound tubular membrane systems have been found to be highly suitable for ultrafiltration applications in the processing Industry and in water pollution control applications. 

Application of the system view to a real-world problem like CE requires that system borders are determined. Examples of systems to be analysed are the man-ufacmring process [29], the R D process [30] or the collaboration process between companies [31]. Determining system borders and the relevant system elements, such as the people that need to be involved, starts with the selection of the focus process, like a design process, a collaboration process, an invention process, a marketing process, a pmchasing process, etc., which determines the system borders and the environment of this system. The enviromnent can be the enviromnent within the organisation as well as the external context in which the organisation operates. The context depends on which process has been chosen for in-depth study, the so-called process of focus. 

Inherent (i.e. intrinsic) safety feature" is a specialized term used in this case to describe the fact that the reactor itself reacts to certain malfunctions without the actuation of active systems or external controlling interventions in such a way that no inadmissible or even dangerous situations can be reached. These reactions are governed by the laws of nature, i.e. they always function regardless of the condition of active systems. This means that they cannot malfunction or fail. The technical and nuclear physical design of the HTR-Module is such that the maximum fuel element temperature always stabilizes itself below 1600°C even in the case of assumed failure of all active shutdown and decay heat removal systems. 

Event Tree Analysis (ETA) is used where appropriate to model all the possible outcomes of a hazard taking account of the mitigations (usually external to the system element in question) that could be used to break an accident sequence ould a hazard occur. Working from left to right, each branch of the Event Tree represents a mitigation to which probabilities can be applied in order to express the relative likelihood of success (S) or failure (F) of the mitigation. 

Relationships are defined among system components and can be both internal among system elements (identified in Table 1.1) and external with the system s environment. The level of control exerted on the system (i.e., at the strategic, tactical, and operational levels) also defines relationships. 

The attributes of the system elements define its state. If the behavior of the elements cannot be predicted exactly, it is useful to take random observations from the probability distributions and to average the performance of the objective. We say that a system is in equilibrium or in the steady state if the probability of being in some state does not vary in time. There are still actions in the system, that is, the system can still move from one state to another, but the probabilities of its moving from one state to another are fixed. These fixed probabilities are limiting probabilities that are realized after a long period of time, and they are independent of the state in which the system started. A system is called stable if it returns to the steady state after an external shock in the system. If the system is not in the steady state, it is in a transient state [15]. 

In order to maintain equilibrium with the element, a system of external nodal forces F is applied which will reduce the virtual work (dW) to zero. In the... 

CCFs and common mode failures (CMFs) are similar in nature in that they are both involved with the simultaneous loss of redundant equipment to a single shared cause. However, they differ by the type of the single shared causal event that causes the redundant items to fail simultaneously. A CCF is caused by an external event, whereas the CMF is caused by an identical failure internal to each item. CMFs normally fail in the same functional mode. Quite often, CMFs are (erroneously) referred to as CCFs. Although it is reasonable to include CMFs under the CCF umbrella, CCFs are much larger in scope and coverage. Figure 2.10 shows this conceptual difference between CCF and CMF. Note that the boxes represent redundant system elements, and the redundancy is effectively shunted by the CMFs and CCFs. Redundancy is the key for identifying CCFs and CMFs. 

Functional and physical interfaces would include mechanical, electrical, thermal, data, control, procedural, and other interactions. Interfaces may also be considered from an internaPexternal perspective. Internal interfaces are those that address elements inside the boundaries established for the system addressed. External interfaces, on the other hand, are those which involve entity relationships outside the established boundaries. In system development, interfaces are generally identified and controlled through the use of interface requirements. 

Dynamic complexity arises in systems that are either significantly influenced by humans or where humans are actually system elements, or, most commonly, both [5]. However, it is convenient to think of dynamic complexity as arising either externally or internally, because the former is more prevalent during the design of a project, whereas the latter is related to the ability of the system to respond to a changing environment during its operation, a subject that is treated under the heading of adaptive systems [6]. 

For reliability, surface area of pressure boundaries should be minimized. This is to include the recuperator and gas cooler. Arrangement and orientation may help protect the system against external impacts, such as from micrometeoroids. (See Section 7 Reliability) As arrangement efforts progressed, one consideration for placement of components would have been shielding of the more vulnerable components by more robust elements and orientation of components so that the more vulnerable surfaces face away from higher particle flux directions. 

Another design, shown ia Figure 5, functions similarly but all components are iaside the furnace. An internal fan moves air (or a protective atmosphere) down past the heating elements located between the sidewalls and baffle, under the hearth, up past the work and back iato the fan suction. Depending on the specific application, the flow direction may be reversed if a propeUer-type fan is used. This design eliminates floorspace requirements and eliminates added heat losses of the external system but requires careful design to prevent radiant heat transfer to the work. 

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