Concept Of Closure Research Articles

사회적 연결은 득인가 실인가: 사회적 연결의 이점과 비용에 관한 연구 동향과 과제

Network theory has traditionally focused on social ties as its primary subject of study, investigating patterns of linkages and relationships among actors and the ensuing social structures from various perspectives. This paper reviews the extant literature on both the positive and negative effects of social ties and social networks. It transcends the mainstream research tradition that has predominantly emphasized positive impacts, presenting domestic and international studies that explore the constraints and costs engendered by social ties, including the excessive homogenization they can cause. Specifically, the paper delves into Granovetter’s (1973) “strength of weak ties” theory, Burt’s (1992, 1995) structural hole theory, which addresses both the patterns of connections and relationships between actors and the resultant structures, and Coleman's (1990) concept of network closure, which underscores the overall structure of social networks. In doing so, this paper presents core tenets of these theories and critically evaluates the current state of knowledge as presented in leading domestic and international management and sociology journals. Finally, considering the implications of networks and their social ties for organizational research, alongside the ease with which individuals can now join various networks through the rapid development of online and mobile social networking sites, the paper underscores the importance of focusing on the costs and constraints that actors face when navigating numerous social connections. It also highlights the necessity of being wary of confirmation bias caused by suggestion algorithms embedded in online sites and proposes directions for future research.

A Truthmaker-based Epistemic Logic

The aim of this work is to investigate the problem of Logical Omniscience in epistemic logic by means of truthmaker semantics. We will present a semantic framework based on W\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varvec{W}$$\\end{document}-models extended with a partial function, which selects the body of knowledge of the agents, namely the set of verifiers of the agent’s total knowledge. The semantic clause for knowledge follows the intuition that an agent knows some information ϕ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varvec{\\phi }$$\\end{document}, when the propositional content that ϕ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varvec{\\phi }$$\\end{document} is contained in her total knowledge. We will argue that this idea mirrors the philosophical conception of immanent closure by Yablo (2014), giving to our proposal a strong philosophical motivation. We will discuss the philosophical implications of the semantics and we will introduce its axiomatization.

On the Link between Plastic Wake Induced Crack Closure and the Fatigue Threshold

This purpose of this paper is to examine the relationship between crack growth equations based on Elber’s original plastic wake induced crack closure concept and the fatigue threshold as defined by the American Society for Testing and Materials (ASTM) fatigue test standard ASTM E647-15el. It is shown that, for a number of conventionally manufactured metals, the function U(R), where R is the ratio of the minimum to maximum applied remote stress, that is used to relate the stress intensity factor ΔK to the effective stress intensity factor ΔKeff is inversely proportional to the fatigue threshold ΔKth(R). This finding also results in a simple closed form equation that relates the crack opening stress intensity factor Ko(R) to ΔK, Kmax, and the fatigue threshold terms ΔKth(R) and ΔKeff,th. It is also shown that plotting da/dN as function of ΔK/ΔKth(R) would appear to have the potential to help to identify the key fracture mechanics parameters that characterise the effect of test temperature on crack growth. As such, for conventionally manufactured metals, plotting da/dN as function of ΔK/ΔKth(R) would appear to be a useful addition to the tools available to assess the fracture mechanics parameters affecting crack growth.

Integer-valued polynomials on subsets of upper triangular matrix rings

S. Frisch, showed that the integer-valued polynomials on upper triangular matrix ring Int T n ( K ) ( T n ( D ) ) : = { f ∈ T n ( K ) [ x ] | f ( T n ( D ) ) ⊆ T n ( D ) } is a ring, where D is an integral domain with field of fractions K. Let R 1 ⊆ R 2 be commutative rings with identity. In this paper, we study the set Int T n ( R 2 ) ( Ω , T n ( R 1 ) ) : = { f ∈ T n ( R 2 ) [ x ] | f ( Ω ) ⊆ T n ( R 1 ) } for some subsets Ω ⊆ T n ( R 1 ) . We generalize Frisch’s result and show that Int T n ( R 2 ) ( T n ( R 1 ) ) : = Int T n ( R 2 ) ( T n ( R 1 ) , T n ( R 1 ) ) is a ring. We state a lower bound for the Krull dimension of the integer-valued polynomials on upper triangular matrix rings. Finally, we state the concept of Skolem closure of an ideal of the integer-valued polynomials on upper triangular matrix rings and as a consequence, we obtain a classification of maximal ideals of the integer-valued polynomials on upper triangular matrix rings.

The role of temperature‐enhanced fault closure in promoting postinjection pressure diffusion and seismicity in enhanced geothermal systems

AbstractPost shut‐in seismic events in enhanced geothermal systems (EGSs) occur predominantly at the outer rim of the co‐injection seismic cloud. The concept of postinjection fracture and fault closure near the injection well has been proposed and validated as a mechanism for enhancing post shut‐in pressure diffusion that promotes seismic hazard. This phenomenon is primarily attributed to the poro‐elastic closure of fractures resulting from the reduction of wellbore pressure after injection termination. However, the thermal effects in EGSs, mainly including heat transfer and thermal stress, may not be trivial and their role in postinjection fault closure and pressure evolution needs to be explored. In this study, we performed numerical simulations to analyze the relative importance of poro‐elasticity, heat transfer, and thermo‐elasticity in promoting postinjection fault closure and pressure diffusion. The numerical model was first validated against analytical solutions in terms of fluid pressure diffusion and against heated flow‐through experiments in terms of thermal processes. We then quantified and distinguished the contribution of each individual mechanism by comparing four different shut‐in scenarios simulated under different coupled conditions. Our results highlight the importance of poro‐elastic fault closure in promoting postinjection pressure buildup and seismicity, and suggest that heat transfer can further augment the fault closure‐induced pressure increase and thus potentially intensify the postinjection seismic hazard, with minimal contribution from thermo‐elasticity.

The Variscan belts of North-West Africa: An African legacy to the Wilson Cycle concept

The concept of cyclic closure and opening of oceans along the same crustal scar was introduced by J.T. Wilson (1966) based on the example of the Atlantic Ocean and its continental borders. At that time, the only Variscan orogen cited south of Europe along the Atlantic coast of Africa was the Mauritanides of Mauritania. Here we report on the recent achievements in the Mauritanides from Mauritania to Morocco, and on the Moroccan Meseta orogen, which also records the Variscan orogeny. The Southern and Central Mauritanides are a poly-orogenic, Pan-African and Variscan orogen characterized by a thin-skinned tectonic style that mirrors the structure of the southern Appalachians, but with a different tectonic history. The Northern Mauritanides crops out in the Moroccan Oulad Dlim massif, northwest of the Reguibat Rise. This part of the belt compares with the southern part, but additionally exhibits in the west a Silurian-Devonian sector that shows possible affinities with Gondwana-derived Appalachian terranes. The Western Meseta is only affected by Variscan events, which were mild in the westernmost Meseta Coastal Block, while the Eastern Meseta was also affected by Eo-Variscan events. The along-strike change from the Mauritanides to the Meseta orogen is interpreted as a transition from a head-on collision south of the South Meseta transform fault (SMF, precursor of the South Atlas Fault, SAF) to a dextral, transpressional collision north of the SMF. South of the SAF, the Anti-Atlas and the Dhlou-Zemmour expose the foreland foldbelts of the Meseta and northernmost Mauritanides. The Coastal Block was likely displaced from the south-westernmost Anti-Atlas during the Early Carboniferous.The Wilson Cycle concept mostly applied in that the Atlantic Ocean opened where the prior Rheic Ocean had closed. Possible exceptions are the Sehoul Block north of Western Meseta and the Silurian-Devonian Sector of the Oulad Dlim massif, which may have separated from NW-Africa and re-amalgamated to it during the Variscan orogeny. Likewise, a NW-African fragment from the Anti-Atlas may have stranded in offshore Massachusetts in eastern North America. An early Ediacaran-Cambrian Wilson cycle nested in the classic cycle introduced by Wilson (1966) occurred along the margin of NW-Africa, where Cadomian terranes rifted off Africa, and some were transferred to Europe and some accreted back to NW-Africa. This early cycle likely controlled the localization of the subsequent Rheic rift, and that of the Atlantic rift along the Mauritanides after the Variscan collision.

Note on Generalized Neighborhoods Structures in Fuzzy Bitopological Spaces

This article's main aim is to study the concepts of the generalized neighborhood and generalized quasi-neighborhood in fuzzy bitopological spaces. It also introduces fundamental theorems for determining the relationships between them. Additionally, some significant examples were examined to demonstrate the significance of the interconnections, some theorems were also introduced to study some main properties of neighborhood structures. Finally, we also studied the concepts of closure, interior, and each of their critical theories and properties by generalized neighborhood systems in fuzzy bitopological spaces.

Swine Model of Biofilm Infection and Invisible Wounds.

Biofilm infection is a major contributor to wound chronicity. The establishment of clinically relevant experimental wound biofilm infection requires the involvement of the host immune system. Iterative changes in the host and pathogen during the formation of such clinically relevant biofilm can only occur in vivo. The swine wound model is recognized for its advantages as a powerful pre-clinical model. There are several reported approaches for studying wound biofilms. In vitro and ex vivo systems are deficient in terms of the host immune response. Short-term in vivo studies involve acute responses and, thus, do not allow for biofilm maturation, as is known to occur clinically. The first long-term swine wound biofilm study was reported in 2014. The study recognized that biofilm-infected wounds may close as determined by planimetry, but the skin barrier function of the affected site may fail to be restored. Later, this observation was validated clinically. The concept of functional wound closure was thus born. Wounds closed but deficient in skin barrier function may be viewed as invisible wounds. In this work, we seek to report the methodological details necessary to reproduce the long-term swine model of biofilm-infected severe burn injury, which is clinically relevant and has translational value. This protocol provides detailed guidance on establishing an 8 week wound biofilm infection using P. aeruginosa (PA01). Eight full-thickness burn wounds were created symmetrically on the dorsum of domestic white pigs, which were inoculated with (PA01) at day 3 post-burn; subsequently, noninvasive assessments of the wound healing were conducted at different time points using laser speckle imaging (LSI), high-resolution ultrasound (HUSD), and transepidermal water loss (TEWL). The inoculated burn wounds were covered with a four-layer dressing. Biofilms, as established and confirmed structurally by SEM at day 7 post-inoculation, compromised the functional wound closure. Such an adverse outcome is subject to reversal in response to appropriate interventions.

On 50 years of fatigue crack closure dispute

AbstractIn this article, we examine the 50 years of observations and interpretations into the subject of fatigue crack closure in lab air and aqueous solutions: disputes and implications. Over this period, several closure concepts have been invoked to explain why the crack propagation threshold ΔKth should reduce with load ratio R. Among these, three types are the most popular and these are closure induced by crack (i) plasticity (PICC), (ii) oxides (OICC), and (iii) roughness (RICC). Therefore, these three and their role in shielding the fatigue crack tip are critically examined. This analysis finds that the reduction in ΔKth with increasing R‐ratio in lab air and aqueous solutions is weakly linked to decreasing crack closure behind the crack tip but strongly related to the access of the environment to the crack tip region and its influence on fatigue damage at and ahead of the crack tip. Supporting evidence for this interpretation comes from the lack of ΔKth dependence on R in a good vacuum (with partial pressure of 10−5 Pa or less). In chemical environments, our viewpoint is supported by a critical analysis of corrosion processes that found that there is insufficient time for most metallic species to form ions, hydrolyze, and transform into hard phases at the crack tip before closure. Therefore, when closure occurs at the crack tip, most of the oxidized metallic species will exist as aquo‐complexes, gel, or colloids that have insufficient shear strength to wedge crack faces during unloading.

A new link prediction method to alleviate the cold-start problem based on extending common neighbor and degree centrality

The cold-start problem occurs when a new user with limited information joins the network, and it becomes challenging to predict new links in future networks. Several studies have proposed link prediction methods based on common neighbors by exploring topology information using the Triadic Closure concept. However, the common neighbor failed to predict future relations because the new user with cold-start problems was isolated and had no common neighbors. This study proposes a common neighbor enhanced by the proposed gravity of node pairs inspired by Newton’s law of gravity called Degree of Gravity for Link Prediction (DGLP). The DGLP considers degree centrality, common neighbors, and distance between candidate node pairs generated by topological information in a single-layer network. The proposed DGLP was evaluated using sixteen datasets and nine benchmark methods. The evaluation results showed that DGLP could increase Area Under the Curve (AUC) values by 7.15%, and the average AUC value reached 0.819 for experiments with 10-fold cross-validation. In addition, the calculated ratio of successfully predicted and node pairs with the cold-start problem achieved 99.94%. The prediction ratio is calculated to ensure that DGLP alleviates the cold-start problem and outperforms benchmark methods.

Experimental investigation of crack opening loads in an aircraft load spectrum

The concept of plasticity-induced fatigue crack closure is indispensable in explaining many fatigue crack growth phenomena; and it is now widely applied in advanced fatigue life evaluation procedures. This concept has been extensively investigated experimentally over the past sixty years using different methods. However, most of these investigations are related to constant amplitude loading or simple load cases such as single or multiple overloads or block loading. In contrast, there are currently no experimental studies investigating crack closure under variable amplitude loading or load spectra, which are more realistic scenarios. This can be attributed to the many difficulties associated with the evaluation of crack opening loads for large numbers of fatigue cycles, including sensor sensitivity, signal noise, data limits, etc. Recently, the authors proposed an advanced piezoelectric sensor for cycle-by-cycle crack opening load measurements, which addresses the above limitations. In this work, the piezoelectric sensor is utilised to investigate crack closure under a typical transport aircraft load spectrum. In particular, it is demonstrated that crack opening load levels can change significantly from cycle-to-cycle, and these levels are typically larger than for constant amplitude loading at the same R-ratio. The relative density plot of crack opening load levels reveals three distinct regions, which can be associated with certain load sequences. The outcomes of this research are important for the development and validation of spectrum compression algorithms as well as advanced fatigue life evaluation procedures.

Toward understanding the emergence of life: A dual function of the system of nucleotides in the metabolically closed autopoietic organization

General structure of metabolism includes the reproduction of catalysts that govern metabolism. In this structure, the system becomes autopoietic in the sense of Maturana and Varela, and it is closed to efficient causation as defined by Robert Rosen. The autopoietic maintenance and operation of the catalysts takes place via the set of free nucleotides while the synthesis of catalysts occurs via the information encoded by the set of nucleotides arranged in polymers of RNA and DNA. Both energy charge and genetic information use the components of the same pool of nucleoside triphosphates, which is equilibrated by thermodynamic buffering enzymes such as nucleoside diphosphate kinase and adenylate kinase. This occurs in a way that the system becomes internally stable and metabolically closed, which initially could be realized at the level of ribozymes catalyzing basic metabolic reactions as well as own reproduction. The function of ATP, GTP, UTP, and CTP is dual, as these species participate both in the general metabolism as free nucleotides and in the transfer of genetic information via covalent polymerization to nucleic acids. The changes in their pools directly impact both bioenergetic pathways and nucleic acid turnover. Here we outline the concept of metabolic closure of biosystems grounded in the dual function of nucleotide coenzymes that serve both as energetic and informational molecules and through this duality generate the autopoietic performance and the ability for codepoietic evolutionary transformations of living systems starting from the emergence of prebiotic systems.

Cycle-by-cycle crack closure measurements and fatigue crack growth in CT specimen made of 7075-T7351 aluminium

In this study, an advanced piezoelectric strain sensor is applied to measure the crack opening loads of a compact tension specimen with a fatigue crack under variable amplitude block loading. The crack opening loads are subsequently utilised to modify the stress intensity factor range by taking into account the proportion of each load cycle for which the fatigue crack remained closed. This effective stress intensity factor is applied to collapse the growth rate curve, which initially displays a strong dependence on stress ratio, into a single master curve where the only variable governing crack extension is the effective stress intensity factor. The findings of this study provide strong evidence for the crack closure concept, which is important for the development of algorithms which can compress/truncate large spectrums. These algorithms rely on a detailed understanding of how much the crack is open or closed during each load cycle. Furthermore, the results indicate that the piezoelectric sensor could be used to study crack closure under realistic spectrum loading conditions, which will be the subject of future investigations.

Subnormality and Theory of L-subgroups

The main focus in this work is to establish that L-group theory, which uses the language of functions instead of formal set theoretic language, is capable of capturing most of the refined ideas and concepts of classical group theory. We demonstrate this by extending the notion of subnormality to the L-setting and investigating its properties. We develop a mechanism to tackle the join problem of subnormal L-subgroups. The conjugate L-subgroup as is defined in our previous paper [4] has been used to formulate the concept of normal closure and normal closure series of an L-subgroup which, in turn, is used to define subnormal L-subgroups. Further, the concept of subnormal series has been introduced in L-setting and utilized to establish the subnor-mality of L-subgroups. Also, several results pertaining to the notion of subnormality have been established. Lastly, the level subset characterization of a subnormal L-subgroup is provided after developing a necessary mechanism. Finally, we establish that every subgroup of a nilpotent L-group is subnormal. In fact, it has been exhibited through this work that L-group theory presents a modernized approach to study classical group theory.

Application of an advanced piezoelectric strain sensor for crack closure measurement

It is well known that fatigue crack growth in airframe structures is governed by sequence effects in aircraft load spectrums, which typically include millions of load cycles of varying amplitude. In predicting the fatigue life of airframe structures, one advanced method used to account for these effects considers the concept of crack closure. This concept requires the measurement or prediction of the load required to open the crack tip, otherwise known as the crack opening load. However, traditional methods used to directly measure the level of crack closure for each cycle tend to be prohibitive for large load sequences. This is mainly due to sensor limitations and large scatter using traditional measurement techniques. The current study proposes a new piezoelectric strain sensor for detection of the crack opening load to addresses these issues. In this work, a comparison is conducted using three sensors on a compact fatigue test specimen: an extensometer (clip gauge), a conventional back face strain gauge, and the piezoelectric strain sensor. It is shown that the piezoelectric strain sensor exhibits far superior performance in measuring the crack opening load relative to the back face strain gauge and the extensometer. At minimum, for all cases considered the piezoelectric strain sensor displayed 100% or better reduction in measurement scatter than the next best sensing method considered. In some cases where the stress ratio is high and the crack length is small, the improvement seen using the piezoelectric strain sensor approached 200%. Crack tip opening loads were detected in almost all cycles across a wide range of crack sizes and load ratios; while the efficiency of the traditional sensors reduced significantly for relatively short cracks and high load ratios. The outcomes of this work will help to better understand the load sequence effects on crack growth rates, improve fatigue life predictive methods and develop effective procedures of truncation/compression of load spectrums for accelerated testing of aircraft components.

V-042 MOVING THE CONCEPT ASSOCIATED TO LAPAROSCOPIC INTRACORPOREAL RECTUS APONEUROPLASTY (LIRA) TO LATERAL HERNIA

Abstract Aims Lateral hernias(LH) are rare and there are difficulties associated to minimally invasive approach, LIRA-technique has been described as an alternative to simple closure of the defect. Despite this, the indications of the concept associated to this technique are beginning to expand to other complex locations. Aims of this video is to show the surgical steps for LH where the concept associated to LIRA is followed to repair this type of hernias. Material & Methods 56-year-old female patient without previous surgical history. Clinical examination and CT-scan showed a LH(L2) 6.4 cm in width(W2) and a length of 6.6 cm. Results We started by opening the peritoneum and fascia, exposing the fibers of the internal oblique and the posterior rectus sheath near the border of the defect. Then, the peritoneum and the fascia transversalis, and medially the posterior aponeurosis of the rectus muscle, are opened. Also, it is important to create a lateral peritoneum flap, using a hybrid procedure that involves a partially extraperitoneal and transabdominal (TAPE), then loop-suture are used for closing the defect. Finally, the mesh is placed intraperitoneally and partially extraperitoneal. Conclusions Best surgical technique for LH is still not clear. The anatomical location of these hernias is challenging, recurrence and bulging are also frequent. Since the introduction of the concept of primary closure of the hernia defect, the surgical repair of hernias in different locations has changed, although the idea of expanding the indication of LIRA could be related to better results in term of recurrences, bulging and pain.

Three Ideas

This two-page comic explores the nexus I found between Scott McCloud’s concepts of closure and iconicity. These concepts have had an immense impact on both my scholarship and my creative work, and my short comic links how they create a more complicated understanding of both sympathy and empathy in a hybridized form. I always found the gutter a compelling site of inquiry, as it metaphorically represents both the collaborative space McCloud propounds and also an epistemological crisis—the gutter is a space of not-knowing, and so is only knowable through a projection which may not bear any relation to the intention of the artist and writer. Furthermore, with whom we are prompted to—and choose—to identify with often prompts a moral crisis. We are as likely to see our reflection in the face of a murderer as a saint in comics, and McCloud’s discussion of iconicity suggests that this creates a more morally complex universe in comics than initially appears.

On proximity focal congested sets in i – topological proximity spaces

In this research, we gave new types of sets on the i – topological proximity space, which depend on both focal nested sets and focal closure concept. We have used names Pf - congested, Pf - uncongested, CPC - congested, Pf C - congested and CPf - congested set of these new concepts. The relations between them and their transport will also be highlighted by a special type of functions.

The Ordeal of a Sixth-Century Josef K: Boethius’ De Consolatione Philosophiae as a Modernist Drama

In recent scholarship, several views have been propounded on the argumentative inconsistencies in Boethius’ De consolatione Philosophiae and the inconclusiveness of its ending. In this article, it is argued that modern scholars still, perhaps unconsciously, adhere to aristotelian concepts of unity, coherence, and closure, which may not be helpful in assessing what Boethius is really trying to say. When analysed from a perspective usually associated with modernist literature, it becomes clear that Boethius’ swan song is neither a deconstruction of “pagan” philosophy nor an implicit plea for Christian spirituality but a an existential drama in which religion and philosophy do not provide any consolation.

A sparse optimal closure for a reduced-order model of wall-bounded turbulence

In the present study, a set of physics-informed and data-driven approaches are examined towards the development of an accurate reduced-order model for a turbulent plane Couette flow. Based on the utilisation of the proper orthogonal decomposition (POD), a particular focus is given to the development of a reduced-order model where the number of POD modes are not large enough to cover the full dynamics of the given turbulent state, the situation directly relevant to the reduced-order modelling for turbulent flows. Starting from the conventional Galerkin projection approach ignoring the truncation error, three approaches enhanced by both physics and data are examined: (1) sparse regression of the POD-Galerkin dynamics; (2) Galerkin projection with an empirical eddy-viscosity model; (3) Galerkin projection with an optimal eddy viscosity obtained from a newly proposed sparse regression – an idea applying the sparse identification of nonlinear dynamics framework to an eddy-viscosity model. The sparse regression of the POD-Galerkin dynamics does not perform well, as the number of POD modes for the given chaotic dynamics appears to be too small. While the unsatisfactory performance of the Galerkin projection model with an empirical eddy viscosity is observed, the newly proposed approach, which combines the concept of an optimal eddy-viscosity closure with a sparse regression, more accurately approximates the chaotic dynamics than the other reduced-order models considered. This is demonstrated with the mean and time scales of the POD mode amplitudes as well as the first- and second-order turbulence statistics.