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Our impressions of this lifeworld are contingent upon our ability to see (in every conflicting meaning of the word). This paper reviews a body of scholars who often share disparate, "incompatible" ontological commitments in effort to examine how their ordering of concepts may reveal a deeper fluidity and permeability between all states of inquiry, creation and investigation into Being and Time. It begins with perspective, examining our subjective presence in the context of the camera apparatus and considers how the mirroring of mechanical instrumentation, namely the rotary shutter and optics of the camera has limited the true function of the cinema to a narrow, representational form. It considers the spiritual implications of the apparatus, exploring, regardless of what is filmed, what the method of inscription from still photos into motion means in regards to consciousness. The paper then investigates what the role of abstraction is in the context of a spiritually minded camera apparatus and attempts to reconcile Deluzian and phenomenological perspectives about film consciousness. All of this is, after all, is in the conceptual support of the four channel video installation Phase Space. The paper does not seek to, or claim to apply readymade philosophical concepts to cinema, rather it explicitly attempts to examine and discuss cinema on its own virtues and investigate how it can express itself as an experimental form of philosophy.

Software designs consist of software components and their relationships. Graphs are abstraction of software designs. Graphs composed of nodes and hyperedges are attractive for depicting software designs. Measurement of abstractions quantify relationships that exist among components. Most conventional metrics are based on counting. In contrast, this work adopts information theory because design decisions are information. The goal of this research is to show that information theory-based metrics proposed by Allen, namely size, complexity, coupling, and cohesion, can be useful in real-world software development projects, compared to the counting-based metrics. The thesis includes three case studies with the use of global variables as the abstraction. It is observed that one can use the counting metrics for the size and coupling measures and the information metrics for the complexity and cohesion measures.

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Projections show that to feed a growing population which is expected to reach 9.1 billion in 2050 would require raising overall food production by some 70 percent by 2050. One of the possible ways to increase agricultural production is through increasing yields by expanding irrigation. This study assesses the potential costs and benefits associated with sustainable groundwater abstraction to provide for irrigation.The feasibility of groundwater abstraction is determined using a combination of three indicators:groundwater recharge, groundwater quality (salinity) and sustainability (no depletion). Global groundwater recharge estimates used, are simulated with the Lund-Potsdam-Jena dynamic global vegetation model with managed lands (LPJmL). The cost of groundwater abstraction is determinedon a spatially explicit scale on global level at a grid resolution of 0.5°. Groundwater abstraction cost is divided into two parts: capital costs and operational costs. The potential benefit of increased water supply for irrigation is given by the water shadow price which is determined by using a Model of Agricultural Production and its Impact on the Environment (MAgPIE). The water shadow price for water is calculated in areas where irrigation water is scarce based on the potential increase in agricultural production through additional water and it reflects the production value of an additional unit of water. The water shadow price is given on a 0.5° grid resolution in US $/m3. Combining the cost of abstraction and the water shadow price, the benefit cost ratio is calculated globally on a spatially explicit scale to determine where investment in groundwater irrigation wouldbe beneficial. Finally, the results are analysed in global, regional and country perspectives. The results show that groundwater abstraction is beneficial for an area of 135 million hectares which is around 8.8% of the total crop area in the year 2005. Europe show the highest potential with an area of ~ 50 million hectares with a majority of the area located in France, Italy, Germany and Poland. Second is North America with an area of ~ 43.5 million hectares located in the Eastern states where the irrigation infrastructure is less developed as compared to the Western states. Sub-Saharan Africa shows a potential of ~ 15.4 million hectares in the Southern and Eastern countries of Zimbabwe, Kenya, Malawi, Tanzania, Ethiopia and some parts of South Africa. South Asia despite extensive groundwater extraction shows only a moderate potential of ~ 9 million hectares, mostly located in India whereas China shows almost no potential. This is due to extensive groundwater depleted areas which were removed from the analysis and low water shadow prices which made abstraction not beneficial. Well installation costs play an important role in developing countries in regions of Sub-Saharan Africa and South Asia, where a reduction in costs would lead to an increase in area by more than 30%. Subsidy analyses shows that substantial increase in crop land areas where a benefit cost ratio >1 takes place in India with subsidised energy prices but this effect is found to be negligible in Mexico. This study is, to the author’s knowledge, the first to assess the benefit cost ratio of groundwater abstraction on a global scale by determining spatially explicit abstraction costs. The results show that a great potential for groundwater abstraction exists in all regions despite problems of groundwater depletion due to disparity in distribution and development of groundwater resources. Energy subsidies and cheap well installation techniques are the two factors that could bring down the abstraction costs which are quite important in developing regions where farm incomes are low. Also, groundwater irrigation potential not only exists in arid areas of Africa and South Asia where irrigation is needed but also in humid areas of Europe and North America where groundwater irrigation can play an important role in building resilience to events of drought. However, it is essential to not to follow the path that has led to groundwater depletion in many parts of the world and develop this potential in a sustainable way through groundwater use regulations, policies and efficient technologies.

yes / This paper critically analyzes the fiction-view of scientific modeling, which exploits presumed analogies between literary fiction and model building in science. The basic idea is that in both fiction and scientific modeling fictional worlds are created. The paper argues that the fiction-view comes closest to certain scientific thought experiments, especially those involving demons in science and to literary movements like naturalism. But the paper concludes that the dissimilarities prevail over the similarities. The fiction-view fails to do justice to the plurality of model types used in science; it fails to realize that a function like idealization only makes sense in science because models, unlike works of fiction, can be de-idealized; it fails to distinguish sufficiently between the make-believe (fictional) worlds created in fiction and the hypothetical (as-if) worlds envisaged in models. Representation characterized in the fiction-view as a license to draw inferences does not sufficiently distinguish between inferences in fiction from inferences in scientific modeling. To highlight the contrast the paper proposes to explicate representation in terms of satisfaction of constraints

Thesis advisor: Peter X. Zhang / Thesis advisor: James P. Morken / Radical reactions have attracted continuous research interest in recent year considering their diverse reactivities. Hydrogen-atom abstraction (HAA), as one type of the most well-explored radical reactions, has been identified as one of powerful tools for C–H functionalization. Reactions involving 1,4-HAA, which is typically a challenging process both entropically and enthalpically, are rather scarce, while 1,5-HAA have been well demonstrated for variety of synthetic applications. Guided by the concept of metalloradical catalysis (MRC), 1,4-HAA was for the first time utilized as the key step to achieve asymmetric construction of chiral ring structures: cyclobutanones, azetidines and tetrahydropyridines. The design of different D2-symmetric chiral amidoporphyrin as the supporting ligand is the key to all these transformations. The reactions can be conducted under mild conditions, affording corresponding ring structure in good yields with excellent selectivity. Furthermore, The combined computational and experimental studies have shed light on the mechanistic details of these new asymmetric radical intramolecular C–H alkylation processes, which are fundamentally different from existing catalytic systems involving metallocarbenes for concerted C–H insertion. We envision that these asymmetric radical processes via Co(II)-based MRC could become an alternative method for important chiral ring structures synthesis and potentially provide new opportunities for complex molecule construction. / Thesis (PhD) — Boston College, 2022. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Conventional testing has become inadequate to satisfy rigorous reliability requirements of embedded software that is playing an increasingly important role in many safety critical applications. Automatic formal verification is a viable avenue for ensuring the reliability of such software. Recently, more and more formal verification techniques have begun modeling a non-Boolean data variable as a bit-vector with bounded width (i.e. a vector of multiple bits like 32- or 64- bits) to implement bit-precise verification. One major challenge in the scalable application of such bit-precise verification on real-world embedded software is that the state space for verification can be intractably large. In this dissertation, several abstraction techniques are explored to deal with this scalability challenge in the bit-precise verification of embedded software. First, we propose a tight integration of program slicing, which is an important static program analysis technique, with bounded model checking (BMC). While many software verification tools apply program slicing as a separate preprocessing step, we integrate slicing operations into our model construction and reduction process and enhance them with compilation optimization techniques to compute accurate program slices. We also apply a proof-based abstraction-refinement framework to further remove those program segments irrelevant to the property being verified. Next, we present a method of using symbolic simulation for scalable formal verification. The simulation involves distinguishing X as symbolic values to abstract concrete variables' values. Also, the method embeds this symbolic simulation in a counterexample-guided abstraction-refinement framework to automatically construct and verify an abstract model, which has a smaller state space than that of the original concrete program. This dissertation also presents our efforts on using two common testability metrics — controllability metric (CM) and observability metric (OM) — as the high-level structural guidance for scalable bit-precise verification. A new abstraction approach is proposed based on the concept of under- and over-approximation to efficiently solve bit-vector formulas generated from embedded software verification instances. These instances include both complicated arithmetic computations and intensive control structures. Our approach applies CM and OM to assist the abstraction refinement procedure in two ways: (1) it uses CM and OM to guide the construction of a simple under-approximate model, which includes only a subset of execution paths in a verification instance, so that a counterexample that refutes the instance can be obtained with reduced effort, and (2) in order to reduce the cost of using proof-based refinement alone, it uses OM heuristics to guide the restoration of additional verification-relevant formula constraints with low computational cost for refinement. Experiments show a significant reduction of the solving time compared to state-of-the-art solvers for the bit-vector arithmetic. This dissertation finally proposes an efficient algorithm to discover non-uniform encoding widths of individual variables in the verification model, which may be smaller than their original modeling width but sufficient for the verification. Our algorithm distinguishes itself from existing approaches in that it is path-oriented; it takes advantage of CM and OM values to guide the computation of the initial, non-uniform encoding widths, and the effective adjustment of these widths along different paths, until the property is verified. It can restrict the search from those paths that are deemed less favorable or have been searched in previous steps, thus simplifying the problem. Experiments demonstrate that our algorithm can significantly speed up the verification especially in searching for a counterexample that violates the property under verification. / Ph. D.