Evaluation Of Theoretical Models Research Articles

Evaluation method of tight sandstone reservoir saturation based on frequency domain electrical dispersion measurement data

The traditional Archie model, which is primarily applicable to medium-high porosity and permeability sandstones, often fails to accurately characterize the the resistivity-saturation relationship in tight sandstones, and it makes the saturation evaluation face great challenges. In this paper, complex resistivity spectrum measurements across 1 kHz to 10 MHz frequencies are performed on tight sandstone reservoir cores. Then, the percentage frequency effect (PFE) values are calculated from complex resistivity modulus at 1 kHz and interfacial polarization frequency under varied saturation states. Furthermore, a new quantitative saturation evaluation model based on the normalized PFE is developed by referring to the normalization method of the resistivity index in the classic Archie formula. The results demonstrate that a good linear correlation between the PFE of the tight sandstone reservoirs and water saturation, and the new saturation evaluation model effectively eliminates electrical differences between samples due to pore structures. Experimental data from tight sandstones shows that higher accuracy of the predicted water saturation by the new saturation evaluation model against measured values compared to the predicted water saturation by the Archie model, and the normalized PFE used in this model can quantitatively evaluate water saturation of tight sandstone reservoirs instead of the traditional Archie formula. The results provide a theoretical model and experimental reference for saturation evaluation in tight sandstone reservoirs.

Tourism destination sustainability: The systematic literature review

<p>The sustainable development of tourism destinations is a continual and evolving process crucial for long-term value and well-being. However, the existing literature reveals a gap in understanding how to effectively evaluate the sustainable development of tourism objects, with a predominant focus on developed countries. This raises concerns about the applicability of similar strategies in underdeveloped nations. This study employs an analysis of the scientific literature to address the identified research problem. We propose a more inclusive and comprehensive approach to sustainable tourism management, aiming to equalize the distribution of economic, social, and cultural dimensions. Our focus is on developing a theoretical evaluation model that goes beyond conventional frameworks and includes both broad and narrow dimensions. The research uncovers that sustainable development, as presented by various authors, encompasses economic benefits, environmental protection, and social dimension management. We introduce a sustainability management model that surpasses existing systems, offering a holistic perspective. Moreover, we emphasize the significance of voluntary publicity for environmental and socio-cultural activities in enhancing a tourism destination’s image and societal value. Our study contributes a theoretical evaluation model based on global criteria for sustainable tourism. This model not only evaluates the dimensions of coherence broadly but also incorporates specific criteria for a nuanced analysis of the current situation and potential opportunities. The proposed framework aims to guide tourism destinations in achieving economic benefits without compromising the environment and prioritizing the well-being of local communities, thus fostering a more sustainable and equitable development process.<strong></strong></p>

Evaluating the variation characteristics of ecological resilience along expressways in developing countries: the case of the Phnom Penh-Sihanoukville Expressway in Cambodia.

Expressway construction has caused a significant threat to the ecological environment in developing countries, and therefore the variation characteristics of ecological resilience along the expressway in developing countries are of major importance. This empirical study focuses on a typical area within a 2-km range of the Phnom Penh-Sihanoukville Expressway in Cambodia and uses remote sensing and geographic information systems (GIS) technology to analyze the variation characteristics of ecological resilience along the expressway. The results of the study reveal that due to the construction of expressways, the land use types transferred into or out of the land use types increase and furthermore the land use types show a trend of decreasing natural attributes and increasing human attributes. It is found that expressway construction has an observed effect on the transfer rate of the center of gravity of land use type, and the direction of the center of gravity shifts in the direction of expressway construction. The impact of construction on the ecological resilience of the western region with higher vegetation coverage was higher than that of the eastern region with higher urbanization. The research develops a theoretical evaluation model based on land use type of the variation characteristics of ecological resilience along the expressway, which can be used to enable the sustainability of expressway construction and maintain the regional ecological environment.

Cognitive processes in pharmacists’ clinical decision-making

BackgroundPharmacists’ clinical decision-making is a core process in pharmaceutical care. However, the practical aspects and effective teaching methods of this process remain largely unexplored. ObjectiveTo examine the cognitive processes involved in pharmacists’ perceptions of how they make clinical decisions in pharmacy practice. MethodsSemi-structured, face-to-face interviews were conducted with pharmacists working in community, outpatient, and hospital care in the Netherlands between August and December 2021. Participants were explicitly asked for examples when asked how they make clinical decisions in practice and how they teach this to others. After transcribing audio-recorded interviews, an inductive thematic analysis was conducted to identify cognitive processes. A theoretical model of clinical decision-making was then used and adapted to structure the identified processes. ResultsIn total, 21 cognitive processes were identified from interviews with 16 pharmacists working in community (n = 5), outpatient (n = 2), and hospital care (n = 9). These cognitive processes were organized into 8 steps of the adapted theoretical model, i.e. problem and demand for care consideration, information collection, clinical reasoning, clinical judgment, shared decision-making, implementation, outcomes evaluation, and reflection. Pharmacists struggled to articulate their clinical decision-making and went back-and-forth in their explanations of this process. All pharmacists emphasized the importance of identifying the problem and described how they collect information through reviewing, gathering, recalling, and investigating. Clinical reasoning entailed various cognitive processes, of which comprehending the problem in the patient's context was deemed challenging at times. Pharmacists seemed least active in evaluating patient outcomes and reflecting on these outcomes. ConclusionsPharmacists use multiple cognitive processes when making clinical decisions in pharmacy practice, and their back-and-forth explanations emphasize its dynamic nature. This study adds to a greater understanding of how pharmacists make clinical decisions and to the development of a theoretical model that describes this process, which can be used in pharmacy practice and education.

Buffeting response analysis – the stack state-space approach

Wind stability and design loads of long-span bridges are assessed applying experimental and theoretical methods. The commonly used approach entails the extraction of fundamental aerodynamic data of key structural elements such as the deck, towers, and cables, either experimentally or numerically, and the application of theoretical models for evaluation of structural responses to turbulent winds. This phenomenon called buffeting is extremely complex and, to date, there is no closed-form theoretical model to reproduce how the wind converts to structural responses and loads which the bridge must resist. The objective of this paper is to explore the base of the problem, namely the transformation of wind gusts to actual loads, and the response estimations. The time domain response approach has been adopted for solution of the generalized equations of motion allowing the exploration of details in the performance of various theoretical interpretations. Starting from the classic quasi-static linear model, theoretical simplifications are removed toward a more complete model of buffeting loads. Non-linear and aerodynamic coupling effects on response predictions are examined specifically aiming at improved buffeting load representations within the framework of the currently available experimental data. A new concept called stack state-space analysis has been introduced for the response solution to wind buffeting. Aerodynamic and structural data of Pierre-Laporte Bridge in Québec City, and the IABSE Working Group 10, long-span bridge validation example, are utilized as representative cases in this study. Avenues for further experimental and numerical validations of the presented new solution approach are suggested toward more accurate predictions of wind response and design loads of long-span bridges.

A theoretical model for performance evaluation of a novel configuration of supersonic ejectors

Few researches have investigated on the improvement of supersonic ejector configuration. This paper presents a theoretical model for evaluating the performance of a novel supersonic ejector configuration that has not been investigated before. Under various geometry parameters and operating conditions, the working performance of ejectors in conventional and novel configurations is investigated. In addition, the performance characteristics of the novel configuration were analyzed, and the Kantrowitz limit was introduced to obtain a reference value for the compression surface radius on a theoretical basis. 24 ejectors with different geometry parameters, including the conventional and novel ejectors, are designed and tested using CFD approach. The results show that the performance of the novel ejectors is better than that of the conventional ejectors within the deterioration point, and the trend of their critical outlet pressure is consistent with the theoretical model. Moreover, the deterioration point is well predicted, and the performance of the novel configuration decreases when the compression surface radius exceeds the deterioration point. Last, the relationship between the flow field and key parameters of the novel configuration was illustrated by analyzing the Mach number contours and pressure distribution of the conventional and novel ejectors.

Data center energy conservation study utilizing loop heat pipes as a chip-level cooling technique and its industrial application

The thermal management and energy consumption for data centers became an increasing challenge due to a significant increase in their number, size and power density in modern information and digitization age. The electricity using by cooling system contributed the important fraction of energy consumption in datacenters, and it is of great significance to carry out the research of new cooling technologies to improve the cooling efficiency of datacenters. This paper initiatively presents the basic energy conservation principle of chip-level cooling technique based on the loop heat pipe (LHP) for natural cooling throughout a year. An energy-saving theoretical evaluation model based on the LHP chip-level cooling method is developed for assessing the energy utilizing efficiency and energy-saving levels in datacenters. Two kinds of real computer servers using two water-cooling LHPs with flat evaporator are introduced. The evaporator volume of a LHP is 54 × 44 × 12 mm3. The tests show that the servers work safely with the inlet water temperature of 40 °C and flow rate of 0.027 m3/h in the condenser of LHP. Lastly, the applications in two industrial data centers based on the LHP chip-level cooling technique are practiced. The annual cooling-PUE of a cloud-computing datacenter in Hohhot city is 1.053, and the annual PUE of a supercomputer-center in Beijing city is 1.15. Their operation data both show that the energy savings of the cooling system and the whole data center could be up to 81 % and 30 % respectively compared to the traditional CRAH cooling technique, which are in accordance with the predicted results of theoretical evaluation model.

PD44 Realistic Review: Theoretical Model For Monitoring And Evaluation (M&E) Of Health Technology Assessment Management

IntroductionRealistic Review (RR) is a methodology for systematic review proposed by Pawson (2002), to guide policy formulation. It is aimed at policy makers and decision makers and seeks to explain how a given intervention succeeds or fails in a certain context, allowing the identification of more suitable alternatives to solve problems. The objective of this study was to develop a theoretical model for Monitoring and Evaluation (M&E) of Health Technology Assessment (HTA) management.MethodsThe realistic review sought to identify aspects that influence HTA contributions. Studies were included if they provided a description of context and description of HTA contributions. Key purpose elements were extracted from selected studies and the contexts of HTA contributions were analyzed. The association between context and types and areas of contributions of HTA in different realities was synthesized. We analyzed thirty-one articles published in international journals in the area of health technology assessment and three articles on assessment policy in Brazil, nominated by experts.ResultsIt was possible to identify situations that generate demands for HTA; favorable and unfavorable contexts and factors for contributions; main functions of networks; main products resulting from the application of evaluations; results and impact predicted by the action of the networks.The logical model starts with conjunctural aspects that generate demands: economic, social and cultural. In a favorable context, the definition of priorities and debates in the negotiation arenas influence research and the policy formulation process. Networks identify evidence and contribute to knowledge management, generating products, results and impacts.ConclusionsThe use of the theoretical model created from the realistic review is a tool that allows the M&E of HTA management.

Performance Analysis and Verification of 14-MeV Fast Neutron Radiography

The ability of 14-MeV fast-neutron radiography (FNR) to inspect bulky objects is evaluated. Both analytical and experimental approaches are used for this purpose. Two important performance parameters—spatial resolution and contrast sensitivity—are theoretically analyzed, especially considering the influence of scatter background and noise. The effect of detection quantum efficiency (DQE) on contrast sensitivity of FNR systems is discussed in this article. To verify the results, film-based neutron radiography experiments were performed using a high-intensity D-T neutron source. Iron samples of varying thickness and containing different detectable structures were used. The visibility and detection capability of the objects were compared with corresponding theoretical results. The results show that the spatial resolution is 0.6 mm and the contrast sensitivity is 2.9 mm for a 3-cm-thick sample. The experiments are in good agreement with theoretical results. This provides a theoretical model for fast-neutron system design and performance evaluation.

Offshore coxswain competency evaluation model for internal on‐board competency monitoring and assessment

AbstractLifeboats are widely installed on offshore facilities to transfer personnel‐on‐board to safe location during an emergency. However, an unacceptably high number of incidents that cause serious or fatal injury to the involved crew still occur during routine maintenance and lifeboat drills. Therefore, a competency evaluation model that is suitable for implementation of on‐board offshore facilities and produces reliable results is essential. This paper proposes a theoretical competency evaluation model to minimize human error and continuously improve the proficiency of offshore lifeboat coxswains in on‐board offshore installations. The offshore coxswain competency evaluation model (OC2EM) is designed in two different sections: Section 1 comprises the base section, and Section 2 comprises the assessment section. OC2EM is assessed with the OPITO Offshore Lifeboat Coxswain Competence Assessment and OPITO Offshore Lifeboat Coxswain Training Standard, which are recognized globally in the oil and gas industry to determine the effectiveness and suitability for implementation. On the basis of the results obtained from the emergency scenarios generated and analysis with the OPITO training and competence standards, OC2EM has proven to be a promising model for implementation in on‐board offshore installations because of its capability to be implemented flexibly depending on the requirement of the particular installation while maintaining realistic results.

Research on Quantitative Evaluation Methods and Influencing Factors of Natural Gas Reservoir Development

Current methods of evaluating the effects of gas reservoir exploitation primarily focus on evaluating production statistics of a well or field, and they often have a certain subjectivity. In order to further analyze key indexes that affect a gas reservoir during production, this paper considered the characteristic parameters of different types of gas reservoirs and established an index system of evaluating a gas reservoir “exploitation effect” from the three aspects of gas reservoir characteristics, rock characteristics, and economic benefits. There are numerous factors affecting the exploitation effect of a gas reservoir. The relationships between different factors are complicated, and the evaluation result of each factor can also be vague. A fuzzy optimization theoretical model for gas reservoir evaluation and optimization was established on the basis of a quantitative study on the evaluation parameters in fuzzy mathematics. In order to clearly understand the influence of each factor on the gas reservoir exploitation effect, numerical simulation was used to perform a multifactor numerical simulation study of the quantitative sensitivity to determine the sequence of different influencing factors in terms of influencing the gas reservoir exploitation effect. This study provides a quantitative scientific basis for the evaluation of gas reservoir exploitation effect.

Analytical model of a T-core coil above a multi-layer conductor with hidden hole using the TREE method for nondestructive evaluation

PurposeIn eddy current nondestructive testing, a probe with a ferrite core such as an E-core coil is usually used to detect and locate defects such as cracks and corrosion in conductive material. However, the E-core coil has some disadvantages, such as large volume and difficulty in the process of winding the coils. This paper aims to present a novel T-core probe and its analytical model used for evaluating hidden holes in a multi- layer conductor.Design/methodology/approachBy using a cylindrical coordinate system, the solution domain is truncated in the radial direction. The magnetic vector potential of each region excited by a filamentary coil is derived, and the expansion coefficients of the solutions are obtained by matching the boundary and interface conditions between the regions. By using the truncated region eigenfunction expansion method, the final expression in closed form for the impedance of the multi-turn coil is worked out, and the impedance calculation is performed in Mathematica. For frequencies ranging from 100 Hz to 100 kHz, both the impedance changes of the T-core coil above the multi-layer conductor without a hidden hole and in the absence of the layered conductor were calculated, and the influence of a hidden hole in the multi-layer conducting structure on the impedance change was investigated.FindingsThe correctness of the analytical model of the T-core coil was verified by the finite element method and experiments. The proposed T-core coil has higher sensitivity than an air-core coil, and similar sensitivity and smaller size than an E-core coil.Originality/valueA new T-core coil probe and its accurate theoretical model for defect evaluation of conductor were presented; probe and analytical model can be used in probe design, detection process simulation or can be directly used in defect evaluation of multi-layer conductor.

Performance evaluation of Masteel's logistics shipping service based on AHP-fuzzy comprehensive evaluation method

The main purpose of this paper is to evaluate the service quality of China United Shipping Logistics of Maanshan Iron and steel company. Based on the relevant theoretical evaluation model and the actual situation of China United Shipping Company of Maanshan Iron and Steel Co., Ltd., the specific dimension index is established to realize the combination of qualitative analysis and quantitative analysis. We mainly use AHP to calculate the weight after obtaining the evaluation index through online survey, network data survey and enterprise internal personnel consulting survey. Finally, we use fuzzy comprehensive evaluation method to evaluate the service level data of this enterprise and draw a conclusion.

Social media-driven customer engagement and movie performance: Theory and empirical evidence

Can social media-driven customer engagement help movie producers to increase movie sales? Movie producers use social media to boost customer engagement; however, our understanding of whether there is a relationship between pre-consumption customer engagement and movie sales is limited. This research explores what drives the success of movies on the opening-weekend. We examine the relationship between pre-consumption customer engagement driven by social media (i.e., personal and interactive engagement) and movie performance (i.e., opening-weekend box office revenues). Driven by the debate about the potential capacity of social media-driven customer engagement to improve movie performance and the limited understanding of the association of pre-consumption customer engagement and movie performance, this research suggests that social media-enabled customer engagement (i.e., personal and interactive engagement) has the potential to improve movie performance, and these two types of engagement can interact to make this effect stronger. We analyze these relationships drawing from the uses and gratifications theory and the social media affordances perspective that motivate customers to interact in social media. The theoretical model evaluation was tested on a unique and original dataset composed of 966 movies released in the U.K. and Spain. The empirical analysis suggests that personal and interactive engagement are positively related to movie performance, and the positive effects of personal and interactive engagement on movie performance are mutually reinforcing. This research contributes to Information Systems (IS) research by theorizing and empirically showing how customer engagement driven by social media creates business value by improving movie performance.

Four-dimensional imaging with virtual reality to quantitatively explore jigsaw puzzle-like morphogenesis of Arabidopsis cotyledon pavement cells.

In most dicotyledonous plants, leaf pavement cells exhibit complex jigsaw puzzle-like cell morphogenesis during leaf expansion. Although detailed molecular biological information and mathematical modeling of this jigsaw puzzle-like cell morphogenesis are now available, a full understanding of this process remains elusive. Recent reports have highlighted the importance of three-dimensional (3D) structures (i.e., anticlinal and periclinal cell wall) in understanding the mechanical models that describe this morphogenetic process. We believe that it is important to acquire 3D shapes of pavement cells over time, i.e., acquire and analyze four-dimensional (4D) information when studying the relationship between mechanical modeling and simulations and the actual cell shape. In this report, we have developed a framework to capture and analyze 4D morphological information of Arabidopsis thaliana cotyledon pavement cells by using both direct water immersion observations and computational image analyses, including segmentation, surface modeling, virtual reality and morphometry. The 4D cell models allowed us to perform time-lapse 3D morphometrical analysis, providing detailed quantitative information about changes in cell growth rate and shape, with cellular complexity observed to increase during cell growth. The framework should enable analysis of various phenotypes (e.g., mutants) in greater detail, especially in the 3D deformation of the cotyledon surface, and evaluation of theoretical models that describe pavement cell morphogenesis using computational simulations. Additionally, our accurate and high-throughput acquisition of growing cell structures should be suitable for use in generating in silico model cell structures.

Selection of Resettlement Site in Reservoir Construction Using Pythagorean Fuzzy MULTIMOORA Multi-criteria Decision-making Method

Jiao, H.B., 2020. Selection of resettlement site in reservoir construction using Pythagorean fuzzy MULTIMOORA multi-criteria decision- making method. In: Bai, X. and Zhou, H. (eds.), Advances in Water Resources, Environmental Protection, and Sustainable Development. Journal of Coastal Research, Special Issue No. 115, pp. 502-505. Coconut Creek (Florida), ISSN 0749-0208.The resettlement is an important part of reservoir construction and the selection of resettlement site is directly related to the success or failure of resettlement work. Existing research don't show enough power to handle the complexity and uncertainty in selection of resettlement site in reservoir (RSR) problem. This study aims to create a theoretical evaluation model using decision making method for RSR selection. Firstly, the factors affecting RSR selection decision-making was constructed. Secondly, based on Pythagorean fuzzy sets, this study constructed Pythagorean fuzzy ratio system, Pythagorean fuzzy reference point approach and Pythagorean fuzzy full multiplicative form. Thirdly, Pythagorean fuzzy MULTIMOORA decision-making method through integrating Pythagorean fuzzy information and MULTIMOORA method was established. Finally, a case study on RSR selecting was presented.

Numerical simulation to determine the fracture aperture in a typical basin of China

Fracture aperture is the main source of uncertainty in reservoir fracture modeling; this uncertainty is due to the difficulty of accurately quantifying underground fracture aperture and the limited understanding of the main factors controlling fracture aperture and the mechanical deformation process. The theoretical evaluation model of underground fracture aperture is a key aspect of fracture characterization and modeling of tight sandstone reservoirs. Based on the self-similarity theory of rock fractures and considering the 3D morphology of a fracture surface, a finite element geomechanical model of a fracture surface is established. A combination of physical experiments and numerical simulations is used to determine the fracture apertures in underground reservoir conditions. Furthermore, a theoretical model of fracture aperture is proposed under the constraints of the in situ stress, rock mechanics parameters, fracture occurrence, fracture scale, fracture filling characteristics and fracture surface characteristics. According to the vertical distribution model of in situ stress, the theoretical average fracture aperture in rock at different depths is determined. With increasing burial depth, the fracture aperture decreases. When the horizontal stress difference is greater than 10 MPa, the effect of the in situ stress difference on the average fracture aperture decreases. Among the three fracture filling patterns considered, the average effective aperture of fractures with uniform filling is the largest. When the fracture spacing is less than 2 m, the fracture aperture increases with increasing fracture spacing; when the fracture spacing is greater than 2 m, the fracture aperture is basically unaffected by the fracture spacing.

THE RESIDENCE PLOT SELECTION MODEL FOR FAMILY HOUSE IN VILNIUS BY NEUTROSOPHIC WASPAS METHOD

Good quality dwelling and the environment are related to the values of citizens’ existence. It can be highlighted as important questions in creating a sustainable living environment. The research and analysis carried out so far include global planning of the plot of a particular country or city according to economic aspects. Meanwhile, our model, which covers the key social aspects of choosing a residential house, will fill this gap. We propose an original problem formulated which includes the planning of the plot of a particular city according to economic, environmental and social aspects. Our work aims to investigate the criteria for the selection of single-family houses and to develop a theoretical evaluation model based on decision-making methods. The presented study deals with the problem of selecting a one-family house plot using the Weighted Aggregate Sum Product Assessment Methods (WASPAS) and the Step-Wise Weight Assessment Ratio Analysis Method (SWARA). During the research, parameters related to plot selection were evaluated: infrastructure, distance, cost, privacy, security and aesthetic view.

Simplified Theoretical Model for Temperature Evaluation in Tissue–Implant–Bone Systems during Ultrasound Diathermy

Deep heating procedures are helpful in treating joint contractures that frequently occur with fractures and joint diseases involving surgical implants and artificial joint prostheses. This study uses a one-dimensional composite medium model consisting of parallel slabs as a simplified approach to shed light on the influences of implants during ultrasound diathermy. Analytical solutions for the one-dimensional transient heat generation and conduction problem were derived using the orthogonal expansion technique and a Green’s function approach. The analytical solutions provided deep insight into the temperature profile by therapeutic ultrasound heating in the composite system. The effects of the implant material type, tissue thickness, and ultrasound operation frequency on temperature distribution were studied for clinical application. In addition, sensitivity analyses were carried out to investigate the influences of material properties on the temperature distribution during ultrasound diathermy. Based on the derived analytical solutions, the numerical simulations indicate that materials with high density, high specific heat, and low thermal conductivity may be optimal implant materials. Among available implant materials, a tantalum implant, which can achieve a lower temperature rise within the tissue (hydrogel) and bone layers during ultrasound diathermy, is a better choice thanks to its thermodynamics.

Integrated theoretical model for performance evaluation of flat-sheet membrane-based absorptive dehumidification module using lithium chloride-water solution

This paper presents an integrated theoretical model to evaluate the performance of a flat-sheet membrane-based absorptive dehumidification module with different flow arrangements (i.e., cocurrent, countercurrent, and cross-flow configurations) using an aqueous lithium chloride desiccant. The model results showed good consistency with experimental data, with a maximum relative error of approximately 7%. The performance of the flat-sheet dehumidification module was evaluated for various air and solution channel heights ranging from 1 to 5 mm at a constant Reynolds number in both channels, in terms of sensible, latent, and total effectivenesses. The sensible effectiveness increased with a decrease in the air channel height and an increase in the solution channel height; in particular, the effect of the solution channel height was more pronounced in the cocurrent flow configuration. In addition, the latent effectiveness increased with a decrease in both channel heights. Thus, there was a trade-off between the effects of the solution channel height on the sensible and latent effectivenesses; consequently, the effect of the solution channel height on the total effectiveness was mitigated. The total effectiveness was observed to decrease in the order of countercurrent, cross-, and cocurrent flow configurations; here, its value in the countercurrent flow configuration was approximately 0.788 when both channel heights were 1 mm.