scholarly journals Relative thermodynamic stability of the [C,N,O] linkages as an indication of the most abundant structures in the ISM

2020 ◽  
Vol 639 ◽  
pp. A16
Author(s):  
I. Fourré ◽  
O. Matz ◽  
Y. Ellinger ◽  
J.-C. Guillemin
Keyword(s):  
Density Functional ◽  
Energy Scale ◽  
Negative Ion ◽  
Future Research ◽  
Stable Isomer ◽  
Energy Principle ◽  
Order Of Magnitude ◽  
The Stability ◽  
High Level

Context. Most of the compounds detected in the interstellar medium (ISM) that possess isomers correspond to the thermodynamically most stable isomer of a given chemical formula. Using the minimun energy principle (MEP) as a pragmatic tool is particularly efficient for less than six atoms, but for larger systems combinatorial analysis gives an intractable numbers of isomers. Aims. To make the MEP more applicable, we look for a chemical sieve to filter the thermodynamic data needed to determine which isomers of complex organic molecules (COMs) have higher chances of being present in the ISM. To do so, we investigate whether the nature of the [C,N,O] elementary fragment can be determinant for the stabilization of COMs, taking C2H3NO as a case study. Methods. We employed standard quantum chemistry methods to determine the ordering of fragments and derivatives on the energy scale. Density functional theory treatments were systematically performed, together with high-level coupled cluster calculations to refine relative energies. Results. For C2H3NO we find methylisocyanate CH3NCO, which is a compound that was very recently detected in the ISM, to be the most stable isomer in a corpus of 40 isomers of lowest energy. In neutral form we find the stability ordering of NCO > ONC; the same is true for the negative ion. Attachments of R=H, CH3, C2H5, HC2, H2CCH, and C6H5 and metals Al and Mg to the nitrogen atom of the NCO fragment provide the most stable isomers. The energy differences between the successive isomers on the energy scale R-NCO, R-OCN, R-CNO, and R-ONC are of the same order of magnitude for all carbonaceous R. Conclusions. Combining the criterion of most stable linkage with the MEP concept should greatly reduce the window of potential targets to be searched for in the ISM. Compounds containing the NCO linkage should be preferential targets of future research.

Supplier Development at LG Electronics

2020 ◽  
Author(s):  
Hyojin Kim ◽  
Daesik Hur ◽  
Tobias Schoenherr
Keyword(s):  
Management Practice ◽  
Digital Technologies ◽  
Supply Management ◽  
Future Research ◽  
Supplier Development ◽  
Environmentally Conscious ◽  
Competitive Capabilities ◽  
The Stability ◽  
Buyer Firm

Supplier development has been a critical supply management practice since the 1990s. In many instances, it has even become imperative for buyer firms to support and prepare their supply bases for uncertain economic and market environments, socially and environmentally conscious customers, advances in digital technologies, and increasing competition. Yet, research that approaches supplier development with the objective to advance all these dimensions in an integrated fashion is scarce. This study fills this void by exploring how a buyer firm may address these emerging challenges in its supply base. Specifically, an in-depth case study of LG Electronics explores how the firm designs and operates multidimensional supplier development activities to foster the stability and sustainability of its supply base while enhancing its core suppliers’ competitive capabilities. This chapter illustrates how supplier development can be taken to the next level, presents implications for managerial practice, and outlines promising future research avenues.

scholarly journals Identifying Digital Transformation Paths in the Business Model of SMEs during the COVID-19 Pandemic

2020 ◽  
Vol 6 (4) ◽  
pp. 104
Author(s):  
Anjar Priyono ◽  
Abdul Moin ◽  
Vera Nur Aini Oktaviani Putri
Keyword(s):  
Business Model ◽  
Digital Literacy ◽  
Environmental Changes ◽  
Small And Medium Enterprises ◽  
Sampling Technique ◽  
Future Research ◽  
Multiple Case ◽  
High Level ◽  
Medium Enterprises

The objective of this study was to analyze how small and medium enterprises (SMEs) cope with environmental changes due to the COVID-19 pandemic by pursuing the business model transformation with the support of digital technologies. To achieve the objective, this study used a multiple case study design with qualitative analysis to examine the data obtained from interviews, observation, and field visits. Seven manufacturing SMEs from Indonesia were selected using a theoretical sampling technique, with the purpose of achieving some degree of variation to allow us to undertake replication logic. Our analysis demonstrates that SMEs adopt a different degree of digital transformations, which can be summarized into three paths, depending on the firms’ contextual factors. First, SMEs with a high level of digital maturity who respond to the challenges by accelerating the transition toward digitalized firms; second, SMEs experiencing liquidity issues but a low level of digital maturity who decide to digitalize the sales function only; and, third, the SMEs that have very limited digital literacy but are supported by a high level of social capital. This last group of firms solves the challenges by finding partners who possess excellent digital capabilities. The qualitative case study method allows us to conduct in-depth and detailed analysis, but has thin generalizability. To address this limitation, future research can use a survey covering various industries to test the proposed theory that has resulted from this study, so that the generalizability can be assured.

Quantum chemistry in the 21st century (Special topic article)

2000 ◽  
Vol 72 (8) ◽  
pp. 1405-1423 ◽  
Author(s):  
Christopher J. Barden ◽  
Henry F. Schaefer
Keyword(s):  
Quantum Chemistry ◽  
Density Functional ◽  
Special Topic ◽  
Future Research ◽  
New Era ◽  
Incremental Development ◽  
Quantum Chemical Methods ◽  
Theoretical Predictions ◽  
Ready Availability ◽  
High Level

Quantum chemistry is the field in which solutions to the Schrödinger equation are used to predict the properties of molecules and solve chemical problems. This paper considers possible future research directions in light of the discipline's past successes. After decades of incremental development—accompanied by a healthy dose of skepticism from the experimental community—the ready availability of fast computers has ushered in a "golden age" of quantum chemistry. In this new era of acceptance, theoretical predictions often precede experiment in small molecule chemistry, and quantum chemical methods play an ever greater role in biochemical and other larger systems. Quantum chemists increasingly divide their efforts along three fronts: high-level (spectroscopic) accuracy for small molecules, characterized by such techniques as Brueckner methods, r12 formalisms, and multireference calculations; parameterization- or extrapolation-based intermediate-level schemes (such as Gaussian-N theory) for medium molecules; and lower-level (chemical) accuracy for large molecules, characterized by density functional theory and linear scaling techniques. These tools, and quantum chemistry as a whole, are examined here from a historical perspective and with a view toward their future applications.

Exploring coordination practices in digital–physical product development

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Stine Hendler
Keyword(s):  
Product Development ◽  
Future Research ◽  
Content Type ◽  
Physical Product ◽  
Problems And Solutions ◽  
Process Output ◽  
The Stability ◽  
Research Initiatives ◽  
Embedded Case Study

PurposeThe paper explores coordination practices in digital–physical product development and their consequences for companies traditionally relying on physical product development.Design/methodology/approachUsing an embedded case study design, the paper reports four action research initiatives addressing the digital–physical coordination challenges encountered by a leading B2C company.FindingsEffective coordination of digital–physical product development, firstly, involves standardization of process, output and skills to accommodate the stability needed for efficient physical product development and manufacturing. Secondly, it involves agile coordination events, such as Scrum ceremonies and PI planning, to facilitate the mutual adjustment needed to allow agility and the differences between digital and physical product development to be continuously and successfully negotiated.Research limitations/implicationsThe paper illustrates a research model with case evidence and suggests tentative theory in the form of propositions. Future research should explore coordination problems and solutions in different digital–physical project types and contexts.Practical implicationsCoordination practices for digital–physical product development are presented and analyzed, providing inspiration for companies.Originality/valueThe paper is the first to explore coordination practices within the emerging field of digital–physical product development.

Modelling the Hydrolysis of Iron-Sulfur Clusters

2019 ◽  
Author(s):  
Murilo H. Teixeira ◽  
Felipe Curtolo ◽  
Sofia R. G. Camilo ◽  
Martin J. Field ◽  
Peng Zheng ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Density Functional ◽  
Catalytic Efficiency ◽  
Implicit Solvent ◽  
Hybrid Functional ◽  
Iron Sulfur ◽  
The Stability ◽  
Dynamics Simulations ◽  
High Level ◽  
Hydrolysis Of

<div>Iron-sulfur (FeS) clusters are essential metal cofactors involved in a wide variety of biological functions. Their catalytic efficiency, biosynthesis and regulation depend on FeS stability in aqueous solution. Here, molecular modelling is used to investigate the hydrolysis of an oxidized (ferric) mononuclear FeS cluster by bare dissociation and water substitution mechanisms in neutral and acidic solution. First, approximate electronic structure descriptions of FeS reactions by density functional theory are validated against high-level wave-function CCSD(T) calculations. Solvation contributions are evaluated by an all-atom model with hybrid quantum chemical/molecular mechanical (QM/MM) potentials and enhanced sampling molecular dynamics simulations. The free energy profile obtained for FeS cluster hydrolysis indicates the hybrid functional M06 together with an implicit solvent correction capture the most important aspects of FeS cluster reactivity in aqueous solution. Then, 20 reaction channels leading to two consecutive Fe--S bond ruptures were explored with this calibrated model. For all protonation states, nucleophilic substitution with concerted bond breaking and forming to iron is the preferred mechanism, both kinetic and thermodynamically. In neutral solution, proton transfer from water to the sulfur leaving group is also concerted. Dissociative reactions show higher barriers and will not be relevant for FeS reactivity when exposed to solvent. These hydrolysis mechanisms may help to explain the stability and catalytic mechanisms of FeS clusters of multiple sizes and proteins</div><div><br></div>

scholarly journals High-Level Synthesis: Productivity, Performance, and Software Constraints

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Yun Liang ◽  
Kyle Rupnow ◽  
Yinan Li ◽  
Dongbo Min ◽  
Minh N. Do ◽  
...  
Keyword(s):  
Stereo Matching ◽  
Feature Matching ◽  
General Purpose ◽  
High Level Synthesis ◽  
Future Directions ◽  
Hardware Implementations ◽  
Rtl Design ◽  
Order Of Magnitude ◽  
High Level

FPGAs are an attractive platform for applications with high computation demand and low energy consumption requirements. However, design effort for FPGA implementations remains high—often an order of magnitude larger than design effort using high-level languages. Instead of this time-consuming process, high-level synthesis (HLS) tools generate hardware implementations from algorithm descriptions in languages such as C/C++ and SystemC. Such tools reduce design effort: high-level descriptions are more compact and less error prone. HLS tools promise hardware development abstracted from software designer knowledge of the implementation platform. In this paper, we present an unbiased study of the performance, usability and productivity of HLS using AutoPilot (a state-of-the-art HLS tool). In particular, we first evaluate AutoPilot using the popular embedded benchmark kernels. Then, to evaluate the suitability of HLS on real-world applications, we perform a case study of stereo matching, an active area of computer vision research that uses techniques also common for image denoising, image retrieval, feature matching, and face recognition. Based on our study, we provide insights on current limitations of mapping general-purpose software to hardware using HLS and some future directions for HLS tool development. We also offer several guidelines for hardware-friendly software design. For popular embedded benchmark kernels, the designs produced by HLS achieve 4X to 126X speedup over the software version. The stereo matching algorithms achieve between 3.5X and 67.9X speedup over software (but still less than manual RTL design) with a fivefold reduction in design effort versus manual RTL design.

Evaluation of the Influence of External Environmental Factors on Logistics Activities: Case Study of Ukrainian Retail Trade Enterprises

2019 ◽  
Vol 9 (7) ◽  
pp. 1593
Author(s):  
Tatyana V. SHTAL ◽  
Anastasiya UVAROVA ◽  
Iuliia I. OSTAPENKO
Keyword(s):  
Environmental Factors ◽  
Consumer Demand ◽  
External Environment ◽  
Retail Trade ◽  
External Factors ◽  
Future Research ◽  
Retail Market ◽  
Logistics Services ◽  
High Level

The article examines the influence of the external environment on the logistics activities of retail trade enterprises of Ukraine. External factors of logistics activities of retail trade enterprises, substantiated indexes of their evaluation were determined. The volume and composition of consumer demand, the development of the market of logistics services, efficiency of logistics activities and the state of competition in the retail market were analysed. Diagnosed the decrease in the efficiency of logistics activities of retail trade enterprises and the high level of its dependence on the factors of environment. The prospect of future research in this direction was formulated.

Renewal and Personal Mastery in Knowledge-Based Organisations

2011 ◽  
pp. 160-179
Author(s):  
Päivi Lohikoski
Keyword(s):  
Intellectual Capital ◽  
Future Research ◽  
Personal Mastery ◽  
Knowledge Based ◽  
Employee Wellbeing ◽  
Structural Capital ◽  
Ict System ◽  
Research Questions ◽  
High Level

Being knowledge management crucial to companies, it seems reasonable to understand an organisation intellectual capital. The three leading components of intellectual capital (human capital, structural capital and relational capital), are intrinsically bounded to the organisational ICT system, organisational structure, and to workers personal mastery. Nonetheless, in order to evolve organisational intellectual capital it is required a high level of personal mastery, which is clearly bounded to human resources. Therefore, this chapter aims to promote a theoretical and empirical discussion in order to understand the diverse dimensions between renewal, personal mastery, and employee wellbeing within a knowledge-based organisation (Finnish ICT-company). For that, the chapter is divided into six major sections: the research questions; theoretical framework and main concepts; the case study organisation and research methods applied; findings; discussion; and future research.

Modelling the Hydrolysis of Iron-Sulfur Clusters

2019 ◽  
Author(s):  
Murilo H. Teixeira ◽  
Felipe Curtolo ◽  
Sofia R. G. Camilo ◽  
Martin J. Field ◽  
Peng Zheng ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Density Functional ◽  
Catalytic Efficiency ◽  
Implicit Solvent ◽  
Hybrid Functional ◽  
Iron Sulfur ◽  
The Stability ◽  
Dynamics Simulations ◽  
High Level ◽  
Hydrolysis Of

<div>Iron-sulfur (FeS) clusters are essential metal cofactors involved in a wide variety of biological functions. Their catalytic efficiency, biosynthesis and regulation depend on FeS stability in aqueous solution. Here, molecular modelling is used to investigate the hydrolysis of an oxidized (ferric) mononuclear FeS cluster by bare dissociation and water substitution mechanisms in neutral and acidic solution. First, approximate electronic structure descriptions of FeS reactions by density functional theory are validated against high-level wave-function CCSD(T) calculations. Solvation contributions are evaluated by an all-atom model with hybrid quantum chemical/molecular mechanical (QM/MM) potentials and enhanced sampling molecular dynamics simulations. The free energy profile obtained for FeS cluster hydrolysis indicates the hybrid functional M06 together with an implicit solvent correction capture the most important aspects of FeS cluster reactivity in aqueous solution. Then, 20 reaction channels leading to two consecutive Fe--S bond ruptures were explored with this calibrated model. For all protonation states, nucleophilic substitution with concerted bond breaking and forming to iron is the preferred mechanism, both kinetic and thermodynamically. In neutral solution, proton transfer from water to the sulfur leaving group is also concerted. Dissociative reactions show higher barriers and will not be relevant for FeS reactivity when exposed to solvent. These hydrolysis mechanisms may help to explain the stability and catalytic mechanisms of FeS clusters of multiple sizes and proteins</div><div><br></div>

Structure-forming units of amino acid maleates. Case study ofL-valinium hydrogen maleate

2016 ◽  
Vol 72 (1) ◽  
pp. 160-163 ◽  
Author(s):  
Denis Rychkov ◽  
Sergey Arkhipov ◽  
Elena Boldyreva
Keyword(s):  
Amino Acid ◽  
Density Functional ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Bulk Powder ◽  
Ft Ir ◽  
The Stability ◽  
Almost All

A new salt of L-valinium hydrogen maleate was used as an example to study structure-forming units in amino acid maleates. This compound was crystallized, its structure solved from single-crystal X-ray diffraction data, and the phase purity of the bulk powder sample confirmed by X-ray powder diffraction and FT–IR spectra. The stability of the new salt was analyzed using density functional theory andPIXELcalculations with focus on theC22(12) structure-forming crystallographic motif. This motif was of particular interest as it is common for almost all maleates. The exceptionally high ability of maleic acid to form salts with various amino acids was rationalized.

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