Enumeration Method Research Articles

The Moderating Role of Supply Chain Agility on the Relationship Between Strategic Flexibility and Organizational Market Performance in Nigerian Pharmaceutical Industry

The pharmaceutical industry is key to the survival of the human race, but equally becoming increasingly susceptible to global disruptions. In Nigeria, records have shown that the industry is plagued with several problems, inclusive of low employee productivity, poor market share, low innovation performance, poor and marginal sales growth and low profitability, which are likely a result of a lack of strategic flexibility in the face of increasing environment turbulence and intense competition. Despite efforts from researchers, the moderating role of supply chain agility has been largely overlooked in the literature. Therefore, this study examines the moderating role of supply chain agility on the relationship between strategic flexibility (resource flexibility, coordination flexibility, proactive flexibility, reactive flexibility and futurity) and organisational performance. A survey research design was used to collect data from 642 management and senior staff employees of six pharmaceutical companies listed on the Nigerian Exchange Group. A total enumeration method was adopted for the study, with a well-structured adapted questionnaire, having Cronbach’s alpha reliability coefficients ranging from 0.725 to 0.945. Partial Least Squares Structural Equation Modeling (PLS-SEM) was chosen to achieve the research goal. The PLS-SEM analysis revealed that strategic flexibility positively affects organizational performance (β = -0.093, p> 0.050, Q2 = 0.644). However, supply chain agility negatively moderates this effect, indicating that while agility is beneficial independently, it can counteract the positive impact of strategic flexibility when combined. The study recommended that the management of pharmaceutical companies in Nigeria should pay serious attention to strategic flexibility as an organizational capability that can enhance performance in the face of increasing uncertainties in and unpredictability nature of the business environment.

Study of Optimal Cutting Paths for Steel Plates Based on Enumeration and Nonlinear Programming

With the development of society and economy, mould processing enterprises have an increasingly strong need to reduce costs and increase economic efficiency. Improving the efficiency of the cutting process is one of the key links to achieve this goal, and the planning of the cutting path occupies a major position in it. Under the condition that the actual cutting distance is fixed, the shortest air distance becomes the goal pursued by enterprises. In this paper, the optimal cutting path problem for steel plates is studied, and the optimal paths under different cutting tasks are found by enumeration method and nonlinear planning model.

The Impact of Forensic Accountant Characteristics on Reducing Tax Evasion from the Perspective of External Auditors Working in Audit Firms and Companies in the Republic of Yemen: A Field Study

The study aimed to identify and measure the impact of forensic accountant characteristics on reducing tax evasion from the perspective of external auditors working in audit firms and companies in the Republic of Yemen. To achieve the study's objectives, an electronic questionnaire was used as a data collection tool from a population of 384 external auditors in audit firms and companies using a complete enumeration method. The number of retrieved questionnaires was 329, and the number of questionnaires valid for analysis was 260. The data were analyzed using the SPSS, where multiple regression analysis was used to test the hypotheses. The results of the field study showed a positive impact of forensic accountant characteristics (skills and qualifications) on reducing tax evasion. Skills had a high positive impact on reducing tax evasion, followed by qualifications, especially those holding a CFA certificate. The results also showed no impact of forensic accountant characteristics (experience and behaviors) on reducing tax evasion according to the study population's opinion. The study revealed that the most related dimensions to reducing tax evasion, according to the study population's perspective, are the justifications for tax evasion, followed by tax evasion opportunities, tax evasion capabilities, and then tax evasion pressures. The study recommends the need to establish a specialized professional association concerned with organizing the forensic accounting profession in the Republic of Yemen, adopting the forensic accounting subject within accounting curricula, and activating field training for those performing the duties of forensic accountants.

Minimal solutions of fuzzy relation equations via maximal independent elements

Fuzzy relation equations (FRE) are a useful formalism with a broad number of applications in different computer science areas. Testing if a solution exists and, if so, computing the unique greatest solution is straightforward. In contrast, the computation of minimal solutions is more complex. In particular, even in FRE with a very simple structure, the number of minimal solutions can increase exponentially. However, minimal solutions are immensely useful since, under mild conditions, they (together with the greatest solution) allow one to describe the entire space of solutions to an FRE. The main result of this work is a new method for enumerating the set of minimal solutions. It works by establishing a relationship between coverings of FRE and maximal independent elements of (hyper-)boxes. We can thus make efficient enumeration methods for maximal independent elements of (hyper-)boxes applicable also to our setting of FRE, where the operator considered in the composition of fuzzy relations only needs to preserve suprema of arbitrary subsets and infima of non-empty subsets. More specifically, we thus show that the enumeration of the minimal solutions of an FRE can be done with incremental quasi-polynomial delay.

Enhancing antimicrobial efficacy against Pseudomonas aeruginosa biofilm through carbon dot-mediated photodynamic inactivation

Pseudomonas aeruginosa biofilms shield the bacteria from antibiotics and the body’s defenses, often leading to chronic infections that are challenging to treat. This study aimed to assess the impact of sub-lethal doses of antimicrobial photodynamic inactivation (sAPDI) utilizing carbon dots (CDs) derived from gentamicin and imipenem on biofilm formation and the expression of genes (pelA and pslA) associated with P. aeruginosa biofilm formation.The anti-biofilm effects of sAPDI were evaluated by exposing P. aeruginosa to sub-minimum biofilm inhibitory concentrations (sub-MBIC) of CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN, combined with sub-lethal UVA light irradiation. Biofilm formation ability was assessed by crystal violet (CV) assay and enumeration method. Additionally, the impact of sAPDI on the expression of pelF and pslA genes was evaluated using real-time quantitative polymerase chain reaction (RT-qPCR).Compared to the control group, the sAPDI treatment with CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN resulted in a significant reduction in biofilm activity of P. aeruginosa ATCC 27853 (P < 0.0001). The CV assay method demonstrated reductions in optical density of 83.70%, 81.08%, 89.33%, and 75.71%, while the CFU counting method showed reductions of 4.03, 3.76, 4.39, and 3.21 Log10 CFU/mL. qRT-PCR analysis revealed decreased expression of the pelA and pslA genes in P. aeruginosa ATCC 27853 following sAPDI treatment compared to the control group (P < 0.05).The results indicate that sAPDI using CDs derived from gentamicin and imipenem can decrease the biofilm formation of P. aeruginosa and the expression of the pelA and pslA genes associated with its biofilm formation.

A census of cubic fourfolds over 𝔽₂

We compute a complete set of isomorphism classes of cubic fourfolds over F 2 \mathbb {F}_2 . Using this, we are able to compile statistics about various invariants of cubic fourfolds, including their counts of points, lines, and planes; all zeta functions of the smooth cubic fourfolds over F 2 \mathbb {F}_2 ; and their Newton polygons. One particular outcome is the number of smooth cubic fourfolds over F 2 \mathbb {F}_2 , which we fit into the asymptotic framework of discriminant complements. Another motivation is the realization problem for zeta functions of K 3 K3 surfaces. We present a refinement to the standard method of orbit enumeration that leverages filtrations and gives a significant speedup. In the case of cubic fourfolds, the relevant filtration is determined by Waring representation and the method brings the problem into the computationally tractable range.

Multi-objective topology optimization of macro structure and microtubule network structure for self-healing material

Abstract Self-healing materials possess the capability to promptly repair minor damages occurring during service, thereby effectively preventing safety accidents. This paper investigates a multi-objective topology optimization method for the macro structure and microtubule network of self-healing materials around pure epoxy resin materials, aiming to enhance the damage healing capability of the microtubule network while meeting the mechanical performance requirements of the macro structure. By introducing the design variables of macro structure and microtubule network, the corresponding topological description functions are established respectively. And study applies logical operations and post-processing techniques to generate an embedded microtubule network structure description. The objective functions include the flexibility of the macro structure, the along-travel head loss, and the total length of the microtubule network, with material volume serving as a constraint. In order to determine the head loss of the three-dimensional microtubule network structure, a Hardy-Cross method based on flow initialization and loop search is proposed. Multi-objective topology optimization is designed based on moving morphable components algorithm, enumeration method and Pareto principle. Develop iterative termination conditions by assessing the disparity between Pareto solution sets in each generation, thereby ensuring algorithm convergence. The numerical example of the Messerschmitt–Bölkow–Blohm (MBB) beamyields a flexibility of 0.059 without a carrier and 0.0728 with a carrier the macrostructural flexibility without a carrier is 81.0% compared to with a carrier, and the macrostructural profiles and the overall flexibility of the MBB beams with/without a carrier are close to each other. This method serves as a reference for optimizing large-scale self-healing structures.

Mating Assay: Plating Below a Cell Density Threshold is Required for Unbiased Estimation of Plasmid Conjugation Frequency of RP4 Transfer Between E. coli Strains

Mating assays are common laboratory experiments for measuring the conjugation frequency, i.e. efficiency at which a plasmid transfers from a population of donor cells to a population of recipient cells. Selective plating remains a widely used quantification method to enumerate transconjugants at the end of such assays. However, conjugation frequencies may be inaccurately estimated because plasmid transfer can occur on transconjugant-selective plates rather than only during the intended mating duration. We investigated the influence of cell density on this phenomenon. We conducted mating experiments with IncPα plasmid RP4 harbored in Escherichia coli at a fixed cell density and mating conditions, inoculated a serial dilution of the mating mixture on transconjugant-selective plates or in transconjugant-selective broth, and compared the results to a model of cell-to-cell distance distribution. Our findings suggest that irrespective of the mating mode (liquid vs solid), the enumeration of transconjugants becomes significantly biased if the plated cell density exceeds 28 Colony Forming Unit (CFU)/mm2 (or 1.68•105 CFU/standard 9 cm Petri dish). This threshold is determined with a 95% confidence interval of ± 4 CFU/mm2 (± 2.46•104 CFU/standard 9 cm Petri dish). Liquid mating assays were more sensitive to this bias because the conjugation frequency of RP4 is several orders of magnitude lower in suspension compared to surface mating. Therefore, if selective plating is used, we recommend to plate at this density threshold and that negative controls are performed where donors and recipients are briefly mixed before plating at the same dilutions as for the actual mating assay. As an alternative, a liquid enumeration method can be utilized to increase the signal-to-noise ratio and allow for more accurate enumeration of transconjugants.

Improving capacity configuration and load scheduling for an integrated multi-sourced cogeneration system

The integration of renewable energy sources and fossil fuel e.g. coal in a heat and power cogeneration system has been proven to be an effective way to reduce CO2 emissions. An integrated multi-sourced cogeneration (IMC) system consisting of wind, solar photovoltaic (PV), and coal-fired combined heat and power (CHP) plant on the energy supply side, is studied in this paper. A bi-level collaborative optimization model for capacity configuration and load scheduling of the wind-PV-coal IMC system is developed. In the upper level, the capacity of wind farm and PV farm are optimized with the enumeration method, while the load scheduling under typical annual conditions is optimized with adaptive particle swarm optimization algorithm in the lower level. The results show that the optimal capacities of wind and PV are 120 MW and 280 MW for the IMC system, respectively. The annual and typical day load scheduling with optimal wind and PV capacities are analyzed. The result of the load scheduling shows that heating and power load distribution unevenly between the two CHP units contributes to reducing total standard coal consumption, which saves 34.96 t in a typical day during the heating season. This study can provide a reference for the capacity configuration and operation scheduling of the IMC system.

Micro‐ and nano‐plastic loads in fish and macroinvertebrates in a tropical river

Abstract This study examines microplastic contamination in river macroinvertebrates and fish within a rapidly urbanising tropical catchment, and provides data on the quantity of microplastics ingested by various taxonomic and functional feeding groups. We employed both a widely used low‐resolution visual inspection method, capable of identifying microplastics ranging from 0.1 to 5 mm, and a novel automated method specifically designed to identify smaller plastics in the nano size range, from 0.004 to 0.1 mm. Analysis using the low‐resolution method indicated that a significant portion of fish (95%) and macroinvertebrates (44%) contained larger microplastics. The composition of microplastic within the animals differed from that in river water and on the river bed: microplastics in the water and on the bed were predominantly fibres (98% and 92% respectively), whereas the animals exhibited a more even mix of fibres (c. 35%), fragments (c. 43%), and film (c. 22%). Microplastic loads in aquatic organisms correlated with feeding group and body size, although patterns were not always consistent. Larger individuals generally contained more microplastic, especially among macroinvertebrates, but this trend was not observed uniformly among fish species. Additionally, differences in body loads among macroinvertebrate taxa and feeding groups varied depending on whether loads were expressed per individual or per unit weight. Use of the high‐resolution enumeration method revealed a substantially higher microplastic count compared to the low‐resolution method, highlighting the potential underestimation of contamination levels by the latter. The study underscores the non‐random uptake of microplastics by aquatic biota, influenced by feeding mode, and stresses the necessity of high‐resolution sample processing for accurate quantification of contamination levels and risk assessment for smaller organisms.

Modeling risk potential fields for mandatory lane changes in intelligent connected vehicle environment

In the environment of Intelligent Connected Vehicles (ICVs), the ICV system is capable of gathering, processing, and transmitting the majority of traffic information to each vehicle, thereby empowering drivers to make more informed and secure decisions. Nevertheless, ICVs are still incapable of completely avoiding traffic conflicts and accidents. Consequently, developing a risk assessment model for ICVs is crucial for their deployment. To investigate the dynamic patterns of lane-changing vehicle risks within ICV environments, this study developed a quantitative relationship model based on the Artificial Potential Field (APF) theory. The model correlates the Total Potential Field (TPF) of mandatory lane-changing (MLC) vehicle with the longitudinal/transverse gravitational potential field (LGPF/TGPF) and the longitudinal/transverse repulsion potential field (LRPF/TRPF). Subsequently, three sets of Human Machine Interface (HMI) systems were developed to delineate distinct ICV environments: baseline, warning group, and guidance group. The baseline furnishes fundamental data, the warning group supplements preceding vehicle icons and real-time headway information, whereas the guidance group additionally augments speed and voice guidance functionalities. Following this, a simulated driving experiment involving 43 participants was carried out to simulate MLC scenarios in highway merging sections. Using enumeration and gradient descent methods, the quantitative relationship between different types of risk fields was determined. The findings indicated that the ICV environment significantly impacts the mean values of LGPF, TGPF, LRPF (Leading Vehicle, LV), and TRPF, while insignificantly affecting the mean value of LRPF (Following Vehicle, FV). Nevertheless, a notable discrepancy in the mean value of LRPF (FV) was observed between the warning and guidance groups. Comparative results with lane positions demonstrate that the proposed TPF accurately depicts vehicle lane-changing behaviors. Comparative results with classical risk indicators indicate that TPF more accurately depicts the actual driving risks and variation trends faced by vehicles in different MLC processes. The research findings will be pivotal in improving real-time control and guidance strategies for vehicles in highway merging sections under ICV environments.

Column generation for the collaborative multi-stop truckload shipping problem in daily regional distribution

Multi-stop truckload shipping offers less-than-truckload shippers a promising way to reduce their freight costs by consolidating freights en route, which is similar to ridesharing in the mobility industry. One significant challenge in practical implementation is designing attractive multi-stop routes that to shippers while conforming to carriers' requirements. It is crucial to develop an efficient optimisation algorithm to automate bundling decisions. However, this routeing problem is complicated by a nonlinear inseparable cost structure and new routeing decisions in the first pickup and last delivery points. We introduce a new variant of pickup and delivery model and propose a column generation algorithm to efficiently solve real-world multi-stop routeing problems. The algorithm utilises a new specialised labelling procedure that exclusively generates labels for pickup sequences and establishes new dominance rules. Theoretical results on the label dominance, algorithm complexity, and optimality gap are also established. We conduct a real-world case study, comparing our methodology against the enumeration method and a heuristic method documented in the literature. The computational results demonstrate the high efficiency of our method and reveal important insights for practitioners.

Occupational Stress Management of Truck Drivers and its Effect on Road Safety: Evidence from Petroleum Tanker Drivers in Lagos State, Nigeria

The feeling of apathy among truck drivers regarding managing their health and work stress is endangering lives and properties on Lagos roads. The study examined occupational stress management of truck drivers and on road safety. The study adopted the descriptive survey research designusing a complete enumeration method (Census).Copies of the questionnaire were distributed to fifty truck drivers who are executive members of the union in the state. The questionnaire was designed on a four-point Likert scale and the study used Pearson Product Moment Correlation and Multiple regression in analyzing the collected data. The findings revealed that there is astrong relationship between fatigue and road safety and a weak relationship between inattention and road safety. The findings further revealed that fatigue and inattention account for 47.8% of road safety issues experienced by truck drivers in Lagos State. The study concluded that the indicators identified for the independent variable are good measures of the occupational stress construct. However, the study recommended among others that employers of truck drivers and their unions should enlighten them and create more awareness of the need for them to pay more attention to their health to ensure the safety of lives and properties on Lagos roads.

Method comparison between hematopoietic progenitor cell and CD34+ cell counts in hematopoietic stem cell collection.

The reference method for hematopoietic stem cell enumeration is flow cytometric CD34+ cell analysis. We evaluated using the hematopoietic progenitor cell (HPC) count on the Sysmex hematology analyzer to safely replace some flow cytometric measurements performed in peripheral blood samples to guide apheresis timing. We compared HPC and CD34+ cell counts in 133 preharvest peripheral blood samples and 124 apheresis products. Pre-apheresis HPC counts ≥24 × 106/L in healthy donors and ≥36 × 106/L in lymphoma patients predicted adequate mobilization with 100% specificity and positive predictive value, saving 79% and 63% of flow cytometry analyses, respectively. Due to a positive bias (mean bias 50.26; 95% CI 36.24-64.29), a higher threshold was needed in multiple myeloma patients (HPC 132 × 106/L), saving only 24% of flow cytometry analyses. When the HPC count is above the corresponding threshold, apheresis could be safely initiated without waiting for the flow cytometry result, thereby reducing time-to-decision. Lower HPC values, however, require confirmation by flow cytometry.

Evaluation of a flow cytometry-based method for determination of T-lymphocyte subtypes for quality assessment of cell therapy products

Chimeric antigen receptor-T (CAR-T) cell therapy is currently the best-known type of immune effector cells therapy. For CAR T-cell therapy, the determination of CD3+ T cells is necessary for the quality control of fresh leukapheresis product as starting material. The aim was to validate analytical method for quantification of percentage and absolute count of T lymphocyte subtypes (CD3+, CD4+ and CD8+ cells) in fresh apheresis products using single-platform method on flow cytometer BD FACS Canto II. Validation study included determination of precision, trueness (bias), assessment of linearity, carryover, comparison of results obtained with two different protocols on flow cytometer for CD3+ cells determination and stability study. For between-run precision coefficients of variation (CVs) were <20%, as well as bias for all T-lymphocyte subtypes. For within-run precision, CVs were <10%, except for low CD8+ cell (percentage 10.51% and viable absolute count 12.37%). Comparison of results obtained with two different protocols for CD3+ cells determination shows no statistically significant difference. Statistically significant differences between results of the analysis of CD4+ cells in fresh samples and results obtained after storage at 4 °C (p = .004) and at room temperature (p = .018) were found. In conclusion, method for enumeration of T-lymphocyte subtypes can be used in routine work on BD FACS Canto II instrument for quality assessment of fresh cell products collected by leukapheresis procedure.

Challenging Complexity with Simplicity: Rethinking the Role of Single-Step Models in Computer-Aided Synthesis Planning.

Computer-assisted synthesis planning has become increasingly important in drug discovery. While deep-learning models have shown remarkable progress in achieving high accuracies for single-step retrosynthetic predictions, their performances in retrosynthetic route planning need to be checked. This study compares the intricate single-step models with a straightforward template enumeration approach for retrosynthetic route planning on a real-world drug molecule data set. Despite the superior single-step accuracy of advanced models, the template enumeration method with a heuristic-based retrosynthesis knowledge score was found to surpass them in efficiency in searching the reaction space, achieving a higher or comparable solve rate within the same time frame. This counterintuitive result underscores the importance of efficiency and retrosynthesis knowledge in retrosynthesis route planning and suggests that future research should incorporate a simple template enumeration as a benchmark. It also suggests that this simple yet effective strategy should be considered alongside more complex models to better cater to the practical needs of computer-assisted synthesis planning in drug discovery.

Соотношения для оценки ошибок установки углового положения в матричных имитаторах радиоэлектронной обстановки

Simplified formulas have been obtained to estimate the error in setting the angular position of the apparent center of radiation in a matrix simulator. The approximation of the error function is used for this purpose. It is shown that the well-known formula for calculating the error in simula¬ting radar reflections from point targets, when used to find the statistical characteristics of noise coordinates of distributed targets, requires simplifications. In this case, the error function can be divided into four sections, within which its approximation by polynomials of the first or second degree is allowed. At the same time, the error function has an oblique symmetry, which makes it possible to analyze only two sections, and to extend the results to four. The numerical enumeration method is used as a way to find an optimal division into sections. For the typical shapes of the main lobe of the directional pattern of the radar antenna, the coefficients of the approximating polynomials were obtained by the Nelder–Meade simplex method. It is shown that the use of approximation makes it possible to obtain analytical expressions for the moments of error in setting the angular position of the apparent radiation center. In particular, the relations for finding the mathematical expectation of an error are given.

MICA Legionella, an innovative and rapid method for enumeration of Legionella pneumophila in French sanitary water

A new innovative method, MICA Legionella, allows for the automatic enumeration of Legionella pneumophila in domestic water samples in 2 days, with a detection limit of 2 CFU per test portion. Here we show that it gives equivalent results to those obtained by the French standard method NF T90–431 in 7 to 15 days.

Multi-objective optimization of parts construction direction by scaling-enumeration method in L-PBF process

PurposePart building orientation (PBO) is an important factor affecting the quality of laser powder bed fusion (L-PBF), which can affect the surface quality and manufacturing cost. The purpose of this paper is to propose a PBO optimization method to optimize the surface roughness and molding time of parts at the same time on the premise of small calculation scale and arbitrary resolution.Design/methodology/approachEfficient and accurate evaluation is an important index of PBO optimization method. In this paper, a PBO optimization method based on scaling enumeration method is proposed, and the surface roughness and molding time of L-PBF parts are modeled as the objective evaluation function of PBO optimization process. To realize multi-objective optimization, an expert system is established, and the fuzzy multiple-attribute group decision-making theory is used to provide weights for each objective evaluation function.FindingsResearch shows that the scaling-enumeration method can optimize the surface roughness and molding time at the same time and get the best PBO. Compared with the traditional method, the surface roughness and molding time are reduced by 1.1% and 0.58%, respectively, and the operation scale of the scaling-enumeration method is reduced by 99% compared with the traditional method. PBO with arbitrary angular resolution can be achieved.Originality/valueThis paper presents a new method to optimize the forming direction of L-PBF parts. This method has small operation scale and accurate results, so it is meaningful for industrial application.

Optimal Design of the Modular Joint Drive Train for Enhancing Cobot Load Capacity and Dynamic Performance

Automation advancements prompts the extensive integration of collaborative robot (cobot) across a range of industries. Compared to the commonly used design approach of increasing the payload-to-weight ratio of cobot to enhance load capacity, equal attention should be paid to the dynamic response characteristics of cobot during the design process to make the cobot more flexible. In this paper, a new method for designing the drive train parameters of cobot is proposed. Firstly, based on the analysis of factors influencing the load capacity and dynamic response characteristics, design criteria for both aspects are established for cobot with all optimization design criteria normalized within the design domain. Secondly, with the cobot in the horizontal pose, the motor design scheme is discretized and it takes the joint motor diameter and gearbox speed ratio as optimization design variables. Finally, all the discrete values of the optimization objectives are obtained through the enumeration method and the Pareto front is used to select the optimal solution through multi-objective optimization. Base on the cobot design method proposed in this paper, a six-axis cobot is designed and compared with the commercial cobot. The result shows that the load capacity of the designed cobot in this paper reaches 8.4 kg, surpassing the 5 kg load capacity commercial cobot which is used as a benchmark. The minimum resonance frequency of the joints is 42.70 Hz.