Ic Field Research Articles

Ndërhyrjet kirurgjikale në zgavrën e gojës para trajtimit protetik

Introduction: Not all patients have the proper anatomy to provide the adequate support for tissue-supported pros- thesis. In these cases, we suggest pre-prosthetic surgery as the best option which helps to provide a suitable prosthet- ic field. Materials and Methods: The study aims to provide a panoramic overview -illustrated with 2 clinical cases- of pre-prosthetic surgical interventions in 79 patients carried out in the Oral Surgery Service at the University Dental Clinic (KSU) in Tirana, from January 2021 to May 2023. Results: 58% of the patients who underwent preprosthetic surgery were female and 42% were male, with a predomi- nance of the 50-60 years old age group (32%). 45% of these patients had no associated pathologies, with the most fre- quent intervention being alveoloplasty in the mandibular region. Conclusion: Pre-prosthetic surgical interventions in hard tissues ensure an adequate prosthetic field. Accurate diagnosis and selection of a correct surgical treatment plan are prerequisites for successful treatment.

Synthesis of poly (amic ester) with controlled molecular weight for photosensitive polyimide in advanced package

Photosensitive polyimide (PSPI) with excellent lithography patterning and superior comprehensive properties have emerged as a very promising material for the advanced electronic package in IC field. Thereinto, poly (amic ester) (PAE) with highly sensitive groups and suitable molecular weight becomes the most important component in PSPI. Herein, a series of PAEs are synthesized by 4,4-oxydiphthalic anhydride, 4,4′-oxydianiline, and 2-hydroxyethyl methacrylate. The molecular weight of PAE was carefully controlled by using phthalic anhydride as the end-capping agent ranging from 9 000–20 000 g/mol. With the cooperation of photoinitiator and crosslinker, high-performance PSPIs were obtained. The results showed that the PAE with a molecular weight of 15 000 g/mol showed the best performance of lithography with resolution of 10 µm. The further increase of the molecular weight resulted the residues after developing, while lower molecular weight exhibited partially imidization during the pre-baking process, leading to a decrease in the solubility of PAE, as well. Additionally, as-prepared PSPIs also performed excellent thermal, mechanical, and dielectric properties, showing tensile strength of 120 MPa, elongation at break of 8%, glass transition temperature and the temperature of 5% weight loss of 260 °C and 430 °C, respectively. All these results exhibit a great application potential for high performance advanced packaging.

Welcome to the Spring 2023 Issue of IEEE Solid-State Circuits Magazine! [Editor’s Note

The focus of the second issue of the 15th year of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">IEEE Solid-State Circuits Magazine</i> is on highlighting some of the many ICs dedicated to biomedical applications. Biomedical ICs are finding their way into a plethora of healthcare applications. They are expected to offer effective ways of diagnosis, treatment, and management of diseases. Furthermore, in addition to reducing the costs and sizes of medical devices, the field of biomedical ICs is enabling new options for surgical procedures, life-saving medical implants, and vital sign monitoring, to name just a few from an array of seemingly limitless opportunities.

Analysis of the B-stars in field of the solar neighborhood young open cluster IC 2391 using UVES spectra and Gaia DR3

In this paper, we present the stellar parameters of individual B-type stars in the IC 2391 young open cluster, using the Barbier-Chalonge-Divan (BCD) Spectrophotometry System, to obtain stellar fundamental parameters from direct measurements of the Balmer discontinuity. This method is optimally suited for late B-stars to determine stellar fundamental parameters, such as effective temperatures, surface gravities, and spectral types, of the stars in the field of IC 2391. We also determined the projected rotational velocity of the stars by matching them with the theoretical LTE model and located our studied stars over the HR diagram. We used the optical, astrometric, and spectroscopic radial velocity data of Gaia DR3 to obtain fundamental parameters of the open cluster IC 2391. For the first time, we used the radial density profile to determine the radius of the cluster. We found that radius to be equal to 1.43 degrees. From 229 members, we found four B-member stars.

Assessment of the history and trends of “The Journal of Intellectual Capital”: a bibliometrics, altmetrics and text mining analysis

PurposeThe Journal of Intellectual Capital (JIC) celebrated its 20th anniversary in 2020. Therefore, the present study aims to provide a general overview of the history and key trends in this journal during 2000–2019.Design/methodology/approachTwo types of citation and textual data during a 20-year journal period were retrieved from the Scopus database. The citation structures and contents were explored based on a combination of bibliometric analysis, altmetric analysis and text mining. The journal themes and trends of their changes were analyzed through citation bursts, mapping and topic modeling. To make a better comparison, the text mining process for the topic modeling of the IC field was performed in addition to the topic modeling of JIC.FindingsBibliometric analysis indicated that JIC has experienced a remarkable growth in terms of the number of publications and citations over the last 20 years. The results indicated that JIC plays a significant role among IC researchers. Additionally, a large number of researchers, institutes and countries have made contributions to this journal and cited its research papers. Altmetric analysis showed that JIC has been shared in different social media such as Twitter, Facebook, Wikipedia, Mendeley, Citeulike, news and blogs. Text mining abstract of JIC articles indicated that “measurement,” “financial performance” and “IC reporting” have the relative prevalence with increasing trends over the past 20 years. In addition, “research trends” and “national and international studies” had a stable trend with low thematic share.Research limitations/implicationsThe findings have important implications for the JIC editorial team in order to make informed decisions about the further development of JIC as well as for IC researchers and practitioners to make more valuable contributions to the journal.Originality/valueUsing bibliometric analysis, altmetric analysis and text mining, this study provided a systematic and comprehensive analysis of JIC. The simultaneous use of these methods provides an interesting, unique and suitable capacity to analyze the journals by considering their various aspects.

Nature Plus Plus Inspired Computing - The Superset of Nature Inspired Computing

The term "Nature Plus Plus Inspired Computing" is coined by us in this article. The abbreviation for this new term is "N++IC." Just like the C++ programming language is a superset of C programming language, Nature Plus Plus Inspired Computing (N++IC) field is a superset of the Nature Inspired Computing (NIC) field. We defined and introduced "Nature Plus Plus Inspired Computing Field" in this work. Several interesting opportunities in N++IC Field are shown for Artificial Intelligence Field Scientists and Students. We show a literature review of the N++IC Field after showing the definition of Nature Inspired Computing (NIC) Field. The primary purpose of publishing this innovative article is to show a new path to NIC Field Scientists so that they can come up with various innovative algorithms from scratch. As the focus of this article is to introduce N++IC to researchers across the globe, we added N++IC Field concepts to the Particle Swarm Optimization algorithm and created the "Children Cycle Riding Algorithm (CCR Algorithm)." Finally, results obtained by CCR Algorithm are shown, followed by Conclusions.

Dos dados ao conhecimento: tendências da produção científica sobre Big Data na Ciência da Informação no Brasil

Objetivo: Este estudo analisa a produção científica acerca da temática do big data na Ciência da Informação no Brasil, a fim de compreender os elementos estruturais dessa produção e como o assunto é discutido no campo da CI, além de suas relações com outras áreas e subáreas do conhecimento.Método: Assume um caráter exploratório, utilizando-se o levantamento bibliográfico como método de coleta dos artigos indexados na base Brapci, entre os anos de 1972 e 2019, além da análise de conteúdo, e da bibliometria como técnica de análise.Resultado: Como resultados, evidencia-se o caráter exploratório e predominantemente teórico desses artigos em detrimento da experimentação e pesquisa de campo. As publicações distribuem-se em 25 periódicos, contudo, 67% dessa produção concentram-se em nove periódicos.Conclusões: O cenário apresentado sinaliza um espaço profícuo para as novas pesquisas da área e um posicionamento estratégico à CI, mas também, uma lacuna a ser preenchida frente a novas exigências de pesquisas que tragam algum impacto social, sendo essa, inclusive, uma das novas dimensões de avaliação dos Programas de Pós-graduação no País, anunciada recentemente pela Capes.

Minimizing Temperature Nonuniformity by Optimal Arrangement of Hotspots in Vertically Stacked Three-Dimensional Integrated Circuits

Abstract The semiconductor packaging technologies have seen its growth from multichip module (MCM), system in package (SiP), system on chip (SoC) to the heterogeneous integration of the MCM. Thermal management of multichip vertically integrated systems poses additional constraints and limitations beyond those for single chip modules. Three-dimensional-integrated circuits (3D ICs) technology is a potential approach for next-generation semiconductor packaging technologies. A 3D IC is formed by vertical interconnection of multiple substrates containing active devices which offer reduced die footprint and interconnect length. This paper discusses the optimal arrangement of two hotspots on each layer of a two-die stacked 3D IC. An analytical heat transfer model for prediction of three-dimensional temperature field of a 3D IC based on the solution of governing energy equations has been developed and used for this study. The model is subject to adiabatic boundary conditions at the walls except for the bottom wall which is subject to convective boundary condition. A feed-forward back propagation artificial neural network (ANN) is employed for obtaining the functional relationship between the location of the hotspots and the objectives. Genetic algorithm is employed for solving two nonconflicting objective functions subject to set of constraints. The first objective aims to minimize the maximum temperature on both layers, and the second objective aims to achieve temperature uniformity in the layers. The results of the optimization study are expected to provide recommendations on the design guidelines for arranging hotspots on vertically stacked substrates.

THE ROMAN MILITARY DIPLOMA AS A HISTORICAL DOCUMENT

The purpose of the article is to analyze and characterize the Roman military diploma as a historical document. The research methodology consists in the use of general scientific methods and principles: a comparative and historiographical analysis, systematization of scientific literature, research works and documents; the principle of historicism, systematicity, scientificity and objectivity. The scientific novelty: on the basis of a wide range of the research es for the first time in the Ukrainian historiography the significance of the Roman military diploma as a historical document ha s been characterized; the prospects of the study of diplomata militum as the sources for the study of the Roman influences on the territory of ancient Ukraine have been elucidated . The Conclusions . During m any years the research es in the field of epigraph ics , including the study of military diplomas, became an important component in the reconstruction of the personnel of the Roman auxiliary units – auxilia, the names of these units, and helped reproduce some other aspects of functioning related not only to the military history. This refers to the administrative apparatus of the Empire, in particular, in addition to the then ruling emperor, in the diplomas the names of consuls, the governor of the province and the commanders of these military units are recorded ; you can also trace the stages of their career – cursus honorum. Analyzing these documents, we can determine the status and place of retired servicemen in their residence places after the honorary resignation ( honesta missio ), to trace the stages and nature of the Romanization of the provinces owing to the quantity of diplomas found and the information about the retiree’s family. It ha s been also noted that the Roman military diplomas from the territory of Ukraine can be an important source for studying some aspects of the history of ancient Ukraine. Nowadays, many issues related to the Roman military diplomas remain not analyzed. For instance, the place of publishing of the imperial constitutions (tabula aenae (aerae)), from which the diplomas were copied , has not yet been identified. The place the diplomas were stored has not been identified either. It is unknown why bronze documents were stopped issuing in the ІІІd century and what are the reasons for their appearance on the territory of the Ukrainian lands. Despite all these gaps, many aspects of this issue have already been studied and this gives us the opportunity to look in a new way at the functioning of such a complex part of the Roman state mechanism as the Roman army.

A non-uniform silicon TFET design with dual-material source and compressed drain

Tunnel FET is the well-built candidate in the field of low-power ICs mainly because of its lower subthreshold swing (SS). But its ON current is relatively small and ambipolar current is high. The advantage of having a lower SS does not hold for higher gate voltages, which leads to higher average SS. In this paper, for the first time, a non-uniform channel with double-material source and compressed drain TFET structure is introduced. The simulation results show that the proposed structure has a minimum point SS of 9 mV/decade and an average SS of 22 mV/decade for a wide range of gate voltages. In addition, the ambipolar current, ON current, and OFF current are obtained to be 10−14 A/μm, 10−5 A/μm, and 10−16 A/μm, respectively, which lead to a remarkable value of the ON–OFF current ratio of about 1011. The effects of trap charge at oxide/semiconductor interface for different trap charge distributions have been investigated. Finally, it is observed that as compared to uniform distribution traps, Gaussian distribution traps degrade the characteristics in terms of ON–OFF current ratio and SS.

Early-career researchers in integrated care: speed networking

Background: Social capital is defined by Putnam and others (Krueter & Lezin 2002) as enabling people to act together to reach shared objectives through membership in networks of informal shared norms and values. With regards to early researchers in integrated care, providing access to meeting other people within the field and to networks in the field can lead to an increase in social capital or in a practical sense career, research, and collaboration opportunities. Aims and Objectives: The aims of this interactive activity are for participants to: - meet other early career researchers in integrated care - meet professionals in the field - discover who to get to know further - discover who works on the same theme/sector - practice using elevator pitch and bio - practice networking (getting to know people and quickly assessing whether to further contact) Format (timing, speakers, discussion, group work, etc): Total time for this activity 90 minutes. (set up 5 minutes; explanation 10 minutes; final discussion 15 minutes) [Time for this activity is dependant on the number of participants] Build 2 groups (1 and 2), each in one row, facing each other (perhaps across tables) Timer: each group has 1 minute to offer information about themselves, first group 1, timer, then group 2. At end of 2 minutes, bell rings, group 1 moves 1 seat to the right. Group 2 remains where they are. Some helpful tips: - Speak loudly and clearly – the room will be full of the noise of networking - Background and research interests - Research history - Goals, needs, wishes - Stay until the end - Bring business cards - If someone is struggling to say or to ask something – help out and ask questions. - Be genuinely interested in everybody - Take time to see if you can help with any connections or advice - At the end: Think about who you want to talk to again and how you can further the new relationship Target audience: The participants are ERIC members, other young professionals 0-5 years in the field of IC, or early career researchers (masters, PhDs or post-doctoral students) in IC. Senior members of IFIC, professionals in the field of IC, participants of ICIC19 who are present and are interested in meeting ERIC members. Learnings/Take away: - Participants will practice using their elevator pitches and bios. - Participants will practice socializing with others in their field. - Participants will meet others with same interests in the IC field for future support and collaborations. - Participants of ERIC will feel more personally part of the network. - Participants will increase their social capital

Competitiveness of Family SMEs in the Supply Chain

Abstract Objective: The goal of the article is to study the problem of identification of the correlation between the goals and development strategies of network structures (organizations) and the goals and strategies of SMEs, realization of their harmonization and synergy effect generation as well as adaptation of typical strategies to the conditions of functioning of small and medium-sized family businesses within network structures. Methodology: Theoretical (critical analysis of sources, data systematization, statistical analysis, comparative analysis, hypothesis formulation, etc.) and empirical (survey method, observation, critical analysis, hypothesis verification, etc.) research methods are used in the article. In order to study the prospects of and readiness of small enterprises for cooperation within network structures an express questionnaire online survey of the representatives of small companies in different sectors of Lviv and Lviv region (Ukraine) was conducted. The sample included 134 respondents. Findings: Calculation and statistical analysis of empirical material collected within the survey has not confirmed the assumption made by the authors about presupposed that the overwhelming majority of the representatives of small and micro enterprises would be open to (ready for) cooperation in the supply chains, ready for close interaction in the field of IC, business process integration with the supply network or chain participants/partners, etc. Only 7.6% are ready to be active participants of network structures, 84.6% are not yet clear about that, while 7.8% object to such cooperation. Less than 40% are ready to integrate their ICs with the ICs of network participants, and the same is the number of those who are not yet clear about that. The largest number of negative answers was given to the question about the readiness to share competences, expertise with network participants – 38.5% and 30.7% are not clear about that. Commodity (service) certification procedure is the direction where the representatives of SMEs showed the strongest readiness for cooperation (69.2%) Value Added: The article suggests a model of the mechanism of strategic development of small and medium-sized family businesses in the supply chain. This model involves, primarily, combination of strategies specific to the micro level and integrated systems, and secondly, delineation of typifying of strategic decisions in such areas as the basic strategies of competitive behaviour, strategies of supply chain development, strategies of supply system planning, relationship institutionalization strategies and specialization strategies. Recommendations: Modern supply networks and chains must possess a considerable elasticity potential that will enable them to successful adjust to the turbulent environment. Such elasticity potential should be developed via involvement of small and medium-sized enterprises with a relatively narrow specialization. Such process must take place in the context of well-grounded decisions of out/insourcing in the distribution system and towards construction of network structures in the strategic dimension. Involvement of small and medium-sized enterprises will contribute to increased elasticity of network structures’ means.

How Come SPICE Is a Verb?: The Natural Course of a Diverse Engineering Tool

The recipient of 2019 IEEE Donald O. Pederson Award in Solid-State Circuits is Dr. Laurence W. Nagel, for the development and demonstration of SPICE as a tool to design and optimize electronic circuits. I think it is fair to say that, in three major ways, no single computer program has had more impact on field of ICs than Simulation Program with Integrated Circuit Emphasis (SPICE) tool (marketing may try to argue that Microsoft PowerPoint has done more to generate revenue, but don't believe them because they always exaggerate).

How to evaluate a Nationwide Whole System Change in Health Care towards Integrated Care for people with Chronic Conditions? Part I: the co-construction of an evaluation framework

Background : The Belgian government program “Integrated Care for better health” www.integreo.be aims at a Nationwide Whole System Change in health and social care. This implies change in its structures, finances, processes and paradigms towards more Integrated Care IC. It concerns geographically defined pilot projects that should cover in ‘full implementation” more than 3.670.000 people, about one third of the total Belgian Population. Pilot projects are both large-scale implementation projects and test cases. Each pilot aims at changing the organization of their loco-regional area network covering up to 150.000 inhabitants towards more IC. Changes are directed at 14 components, structured at three levels: 1 the patient level e.g. case management; 2 the inter-professional collaboration level e.g. shared medical file; and 3 the inter-organizational collaboration at loco-regional level e.g. quality culture The ultimate goal is to improve the ‘Triple Aim’ quality of care, equity and the work life of healthcare providers ‘TA2+’. A scientific team was appointed to : design and implement an evaluation framework alongside the pilot-projects-in-development. function as a support mechanism to the pilot projects in assisting and accompanying them with their self-evaluation process. function as a support mechanism for the government agencies who induced and guide the change management program. Existing research on achieving sustainable change of loco-regional networks towards more IC and Triple Aim within a nation-wide program is scarce. Moreover, existing research is highly context specific. This need to be taken into account in the generalization process. Aim : To reflect with the target audience on the necessity of changing research paradigms towards theory driven appraisals when engaging into Whole System Change evaluation in healthcare. Format : Interactive workshop with both ‘teasing’ questions to the target audience and presentation of our lessons learned Speakers: Geert Goderis, Jean Macq, Nathan Charlier, Elien Colman. Target Audience : Researchers and professionals active in the field of IC and system change. Learnings : - System change towards IC cannot be conceived as a delineated intervention, but as a complex strategy or even a policy to innovate and implement long-lasting change. This complexity often manifests as shifting and unpredictable contexts, deep differences among perspectives, and even conflict among stakeholders. - Scientific evaluation is necessary and imposes a paradigm change for the involved scientists. ‘Laboratory like’ methodologies type ‘Randomized Controlled Trials’ are unfit and must be replaced by theory driven approaches, describing the processes and contextual factors leading to desired outcomes. - The evaluation should transcend the question ‘what works?’ towards questions on how, why, for whom and in what circumstances the program brings the desired outcomes, in order to allow upscaling of the program to a system change covering entire Belgian territory. - Scientists engage in a co-creative process producing new knowledge, in partnership with all other involved stakeholders like e.g. health professionals and government agents. This co-creation process disables the possibility to plan a fixed endpoint: the design is tribute to multiple issues that evolve over time. Meanwhile, the whole program serves as a leverage to create breakthroughs in these issues.

Multiple Roads Travelled: A Career Panel on Integrated Care for the Next Generation of Researchers and Practitioners

Background: The Early-career Researchers in Integrated Care ERIC recognizes that interdisciplinary knowledge exchange, collaboration, mentorship and fostering connections are key ingredients of success in the field of integrated care IC. The network was developed to support researchers who are relatively new to the field but are passionate about improving quality of care, patient/caregiver experiences and outcomes through care integration. Aims and Objectives: Participants will have the opportunity to hear from a mixed panel of members from the field of IC, who will discuss their experiences navigating the field at different career stages and disciplines. This will include: 1 senior policy maker, 2 senior researchers, 1 post-doctoral fellow. The objective of the panel discussion is to give the audience a glimpse in to the different approaches, tools and skills senior researchers in the past have used to either: 1- achieve career milestones in IC; or 2- overcome major research or policy challenges Format/Outline: Panel discussion with interactive audience participation The workshop will be recorded via video and posted on the ERIC webpage for other members to access in the future. As well, highlights will be captured by rapporteur, and delivered as a sharable resource/output. Total time: 60-90 minutes 15 minutes: Brief overview of ERIC, overall goals of the network 20 minutes: Introduction and overview of the panel members scope of work and research 45 minutes: The hosts will ask each of the panel members to share with the audience key discussion points such as: 1- How did you end up in the field of IC/what was the turning point/did you always know you would be in IC research or policy? 2- Looking back at your early career, what did you do/wish you did more of to prepare you for the current landscape of IC? 3- For the senior panelist: In your experience, can you share an example of a major policy or research challenge related to IC in that was difficult to overcome? What was helpful in overcoming it? 4- For the senior panelists: When looking at applicants or promising candidates, what are 3 characteristics you look for in a junior researcher or young professional? 5- For all panelists: How do you envision the current generation of early-career researchers and practitioners making an impact in the future direction of the IC field? 20 minutes: Open floor for the audience to ask panelists questions Audience: The audience may include young professionals usually 0-5 years in the field, or early career researchers masters, PhDs or post-doctoral students, working or interested in advancing IC in their local context. Learnings/Take away: This career panel discussion provides capacity for early-career researchers to prospectively think about the direction and scope of their research as it relates to IC. The open panel discussion also encourages them to potentially seek mentorship from more senior leaders in the field and to learn from their best practices moving forward.

Editorial board interlocking in knowledge management and intellectual capital research field

Due to the importance of academic journals, it is critical to understand how they can create influence on research fields. An alternative way to understand how scholarly journals create influence in academic fields is to analyze the editorial board interlockings (EBI) and how they may generate networks within academic fields. EBI is the term used to describe the general circumstance where the same scholar is a member of multiple editorial boards, which creates a social network dimension within and between academic journals. The aim of this paper is to examine EBI phenomenon within knowledge management and intellectual capital fields (KM–IC). Assuming that EBI creates a social structure within scholarly journals, this paper investigates how KM–IC journals are connected through EBI, which journals are the most influential within KM–IC field and identify if KM–IC scholarly journal network breaks into subgroups. Social network analysis was the method applied using data from KM–IC ranking. Results identified the scholarly journal network, the high influence journals, and the cohesive subgroups within KM–IC field.

New insights into the interstellar medium of the dwarf galaxy IC 10: connection between magnetic fields, the radio–infrared correlation and star formation

We present the highest sensitivity and angular resolution study at 0.32 GHz of the dwarf irregular galaxy IC\,10, observed using the Giant Metrewave Radio Telescope, probing $\sim45$ pc spatial scales. We find the galaxy-averaged radio continuum spectrum to be relatively flat, with a spectral index $\alpha = -0.34\pm0.01$ ($S_\nu \propto \nu^\alpha$), mainly due to a high contribution from free--free emission. At 0.32 GHz, some of the H{\sc ii} regions show evidence of free--free absorption as they become optically thick below $\sim0.41$ GHz with corresponding free electron densities of $\sim11-22~\rm cm^{-3}$. After removing the free--free emission, we studied the radio--infrared relations on 55, 110 and 165 pc spatial scales. We find that on all scales the non-thermal emission at 0.32 and 6.2 GHz correlates better with far-infrared (FIR) emission at $70\,\mu$m than mid-infrared emission at $24\,\mu$m. The dispersion of the radio--FIR relation arises due to variations in both magnetic field and dust temperature, and decreases systematically with increasing spatial scale. The effect of cosmic ray transport is negligible as cosmic ray electrons were only injected $\lesssim5$ Myr ago. The average magnetic field strength ($B$) of $12~\mu$G in the disc is comparable to that of large star-forming galaxies. The local magnetic field is strongly correlated with local star formation rate ($\mathrm{SFR}$) as $B \propto \mathrm{SFR}^{0.35\pm0.03}$, indicating a star-burst driven fluctuation dynamo to be efficient ($\sim10$ per cent) in amplifying the field in IC\,10. The high spatial resolution observations presented here suggest that the high efficiency of magnetic field amplification and strong coupling with SFR likely sets up the radio--FIR correlation in cosmologically young galaxies.

Studies on effect of various surfactants on stable dispersion of graphene nano particles in simarouba biodiesel

Discovery of graphene has inspired researchers a range of potential applications. Conventional fluids with nanoparticle of size 1-100nm dispersed in them are called Nanofluids. Nanofluids are found to possess increased physical and thermal properties like thermal diffusivity, viscosity, thermal conductivity and convective heat transfer coefficient. These properties can be explored in the field of IC engines as additives in improving the engine performance and reducing the harmful emissions like NOx, CO, UBHC etc. In this work, a comparative study of two anionic dispersants Sodium Dodecyl Sulfate (SDS) and Sodium Dodecyl Benzene Sulfonate (SDBS) as dispersants for stable dispersion of graphene in Simarouba biodiesel with 20%blend in diesel (SME20) was made. Nanofluids samples of graphene at 20ppm and different mass fraction of SDBS & SDS were prepared. Dispersion of graphene was achieved by ultrasonication and magnetic stirring. Dispersion was characterized with Ultra Violet Visible (UV-Vis) spectroscopy. The UV-Vis absorption spectra revealed the presence of Graphene with characteristic λmax at around 250 nm. Experimental result showed that with increase in concentration of dispersant, the value of absorbance also increased. There is a linear relation between stability of dispersion and UV absorbency. An optimum graphene- to-surfactant ratio was determined. Surfactant concentration above or below this ratio was shown to decreases the stability of dispersion. For a mass fraction of 1:4, Graphene to SBDS ratio, the absolute value of UV absorbency was highest. Dispersion stability of SDBS was better than SDS at all concentration levels.

Identification of Large-Scale Structure Fluctuations in IC Engines using POD-Based Conditional Averaging

Cycle-to-Cycle Variations (CCV) in IC engines is a well-known phenomenon and the definition and quantification is well-established for global quantities such as the mean pressure. On the other hand, the definition of CCV for local quantities, e.g. the velocity or the mixture distribution, is less straightforward. This paper proposes a new method to identify and calculate cyclic variations of the flow field in IC engines emphasizing the different contributions from large-scale energetic (coherent) structures, identified by a combination of Proper Orthogonal Decomposition (POD) and conditional averaging, and small-scale fluctuations. Suitable subsets required for the conditional averaging are derived from combinations of the the POD coefficients of the second and third mode. Within each subset, the velocity is averaged and these averages are compared to the ensemble-averaged velocity field, which is based on all cycles. The resulting difference of the subset-average and the global-average is identified as a cyclic fluctuation of the coherent structures. Then, within each subset, remaining fluctuations are obtained from the difference between the instantaneous fields and the corresponding subset average. The proposed methodology is tested for two data sets obtained from scale resolving engine simulations. For the first test case, the numerical database consists of 208 independent samples of a simplified engine geometry. For the second case, 120 cycles for the well-established Transparent Combustion Chamber (TCC) benchmark engine are considered. For both applications, the suitability of the method to identify the two contributions to CCV is discussed and the results are directly linked to the observed flow field structures.

Role of Viscosity Ratio in Liquid-Liquid Jets under Radial Electric Field

The effect of viscosity ratio (λ, defined as viscosity of surrounding medium/viscosity of fluid jet) on st ability of axisymmetric (m=0) and asymmetric (m=1) modes of perturbation on a liquid-liquid jet in presence of radial electr ic field (E 0 ), is studied using linear stability analysis. The viscos ity ratio is shown to have a damping effect on both the modes of perturba tion. However the effect was found more pronounced for the m=1 mode as compared to m=1 mode. Investigating the effect of b oth E 0 and λ simultaneously, an operating diagram is generated, which clearly shows the regions of dominance of the two modes for a range of electric field and viscosity ratio values.