scholarly journals Designing a Multi-Stage Transport System Serving e-Commerce Activity

2021 ◽  
Vol 13 (11) ◽  
pp. 6154
Author(s):  
Aurelija Burinskienė
Keyword(s):  
Transport System ◽  
Policy Development ◽  
Methodological Approach ◽  
Transport Systems ◽  
Distance Metrics ◽  
Location Selection ◽  
Practical Applications ◽  
Multi Stage ◽  
Warehouse Location ◽  
Business Customers

In this paper, the author designs an e-commerce transport system, which covers the locations of producers’ facilities, distribution warehouses, and the business customers and deliveries among them. The study aims to identify the best locations for warehouses to increase efficiency in multi-stage transport systems. To reach this goal, the author revises distance metrics and suggests a methodological framework useful for warehouse location selection and practical applications. The empirical research is delivered by selecting a warehouse location using the maximal coverage model and mandatory closeness distance condition. After analyzing four warehouses’ alternatives, results are presented by applying various distance metrics. The results show that the selection of the location of the main warehouse depends on the level of returns that are defined by using the Mersenne Twister algorithm, and the distance calculation metrics representing differences in ranking. By the end of the study, the recommendation is given to apply the presented methodological approach for decision-makers seeking to improve service distances where decisions are made using path-based service distance criteria. The increase of efficiency is important from a policy development perspective, as findings of the study could help to reduce transport delivery costs for customers.

Heave Induced Internal Flow Fluctuations in Vertical Transport Systems for Deep Ocean Mining

2014 ◽  
Author(s):  
Stephan D. A. Hannot ◽  
Jort M. van Wijk
Keyword(s):  
Transport System ◽  
Internal Flow ◽  
Deep Ocean ◽  
Vertical Transport ◽  
Transport Systems ◽  
Ship Motions ◽  
Centrifugal Pumps ◽  
Mining System ◽  
Pump System ◽  
Ocean Mining

Deep ocean mining systems will have to operate often in harsh weather conditions with heavy sea states. A typical mining system consists of a Mining Support Vessel (MSV) with a Vertical Transport System (VTS) attached to it. The transport system is a pump pipeline system using centrifugal pumps. The heave motions of the ship are transferred to the pump system due to the riser-ship coupling. Ship motions thus will have a significant influence on the internal flow in the VTS. In this paper, the influence of heave motions on the internal flow in the VTS for a typical mining system for Seafloor Massive Sulfide (SMS) deposits in Papua New Guinea is analyzed. Data on the wave climate in the PNG region is used to compute the ship motions of a coupled MSV-VTS. The ship motions then are translated into forces acting on the internal flow in order to compute fluctuations in the internal flow. In this way, the workability of the mining system with respect to the system’s production can be assessed. Based on a detailed analysis of the internal flow in relation to ship motions, the relevance of a coupled analysis for the design of VTS is made clear. This paper provides a method for performing such analyses.

scholarly journals Trk2 Potassium Transport System in Streptococcus mutans and Its Role in Potassium Homeostasis, Biofilm Formation, and Stress Tolerance

2016 ◽  
Vol 198 (7) ◽  
pp. 1087-1100 ◽  
Author(s):  
Gursonika Binepal ◽  
Kamal Gill ◽  
Paula Crowley ◽  
Martha Cordova ◽  
L. Jeannine Brady ◽  
...  
Keyword(s):  
Stress Tolerance ◽  
Streptococcus Mutans ◽  
Transport System ◽  
Biofilm Formation ◽  
Cellular Response ◽  
Pathogenic Bacteria ◽  
Transport Systems ◽  
Content Type ◽  
Growth And Survival ◽  
Dental Biofilm

ABSTRACTPotassium (K+) is the most abundant cation in the fluids of dental biofilm. The biochemical and biophysical functions of K+and a variety of K+transport systems have been studied for most pathogenic bacteria but not for oral pathogens. In this study, we establish the modes of K+acquisition inStreptococcus mutansand the importance of K+homeostasis for its virulence attributes. TheS. mutansgenome harbors four putative K+transport systems that included two Trk-like transporters (designated Trk1 and Trk2), one glutamate/K+cotransporter (GlnQHMP), and a channel-like K+transport system (Kch). Mutants lacking Trk2 had significantly impaired growth, acidogenicity, aciduricity, and biofilm formation. [K+] less than 5 mM eliminated biofilm formation inS. mutans. The functionality of the Trk2 system was confirmed by complementing anEscherichia coliTK2420 mutant strain, which resulted in significant K+accumulation, improved growth, and survival under stress. Taken together, these results suggest that Trk2 is the main facet of the K+-dependent cellular response ofS. mutansto environment stresses.IMPORTANCEBiofilm formation and stress tolerance are important virulence properties of caries-causingStreptococcus mutans. To limit these properties of this bacterium, it is imperative to understand its survival mechanisms. Potassium is the most abundant cation in dental plaque, the natural environment ofS. mutans. K+is known to function in stress tolerance, and bacteria have specialized mechanisms for its uptake. However, there are no reports to identify or characterize specific K+transporters inS. mutans. We identified the most important system for K+homeostasis and its role in the biofilm formation, stress tolerance, and growth. We also show the requirement of environmental K+for the activity of biofilm-forming enzymes, which explains why such high levels of K+would favor biofilm formation.

scholarly journals A LEXICOGRAPHIC OPTIMIZATION APPROACH FOR BERTH SCHEDULE RECOVERY PROBLEM IN CONTAINER TERMINALS

Transport ◽  
2016 ◽  
Vol 31 (1) ◽  
pp. 76-83 ◽  
Author(s):  
Qian Zhang ◽  
Qingcheng Zeng ◽  
Hualong Yang
Keyword(s):  
Container Terminals ◽  
Optimization Approach ◽  
Technical Problems ◽  
Trade Off ◽  
Practical Applications ◽  
Lexicographic Optimization ◽  
Multi Stage ◽  
Schedule Recovery ◽  
Equipment Failures ◽  
Recovery Problem

In container terminals, the planned berth schedules often have to be revised because of disruptions caused by severe weather, equipment failures, technical problems and other unforeseen events. In this paper, the problem of berth schedule recovery is addressed to reduce the influences caused by disruptions. A multi-objective, multi-stage model is developed considering the characteristics of different customers and the trade-off of all parties involved. An approach based on the lexicographic optimization is designed to solve the model. Numerical experiments are provided to illustrate the validity of the proposed Model A and algorithms. Results indicate that the designed Model A and algorithm can tackle the berth plan recovery problem efficiently because the beneficial trade-off among all parties involved are considered. In addition, it is more flexible and feasible with the aspect of practical applications considering that the objective order can be adjusted by decision makers.

scholarly journals Regarding some aspects of economic feasibility for the transport integrated use in favor of environmental security

2018 ◽  
Vol 170 ◽  
pp. 05001 ◽  
Author(s):  
Ruben Kazaryan
Keyword(s):  
National Security ◽  
Transport System ◽  
Developed Countries ◽  
Climatic Conditions ◽  
Environmental Security ◽  
Economic Feasibility ◽  
Transport Systems ◽  
Domestic Water ◽  
European Area ◽  
High Dynamics

The transport system in Russia and the transport support issues of national security differ completely from the Occident and other developed countries due to geostrategic and natural climatic conditions of our country. The integrated transport system, where in a sufficiently coherent manner used are the roads and railways, domestic water and air ways, pipeline transport, is more developed in the European area of the country. However there is no assessment of economic feasibility for the integrated transport lines. Firstly, assessment criteria for the transport support efficiency in favor of environmental security; secondly, mathematical economic models of various transport types integrated use in favor of environmental security; thirdly, economic feasibility methods for transport integrated use in favor of environmental security, that unavoidably leads to unreasonable transport operations using the existing rail and water ways at little distances, and increases their base cost by several times versus the transport by road. High dynamics of transport support for economic, demographic and environmental security within a market economy require the development of approach for the transport integrated use in favor of Russia national security. This article describes some practical recommendations for transport systems control bodies.

scholarly journals Determining the Extent of Territorial Transport Services When Using Rail Transport

2019 ◽  
Vol 10 (2) ◽  
pp. 61-69
Author(s):  
Milan Dedík ◽  
Jozef Gašparík ◽  
Nikolina Brnjac
Keyword(s):  
Transport System ◽  
Rail Transport ◽  
Transport Systems ◽  
Transport Service ◽  
Factors Affecting ◽  
Transport Services ◽  
Complex Process ◽  
The Subject ◽  
Efficient Transport ◽  
Transport Potential

Abstract Planning the extent of transport services within a selected territory is a topical issue especially in the context of developing integrated transport systems. The objective of this research study is to design a sustainable system of public passenger transport that would be an alternative to expanding individual transport. The implementation of a quality and efficient transport service is a relatively complex process, since, currently, there are no generally applicable principles for its design. This manuscript presents general results of research aimed at solving the problem of transport service within a selected territory issue with a focus on rail transport as an efficient transport system representing a backbone of a transport system. The subject of the investigation is to compile a set of factors affecting the design of the transport concept. The output of the manuscript consists in a proposal of a generally applicable procedure including a calculation of transport potential and characteristics of the inputs. Subsequently, based on the resulting values, it will be possible to determine the extent of the transport services provided by rail transport in any territory, which will contribute to a more efficient and high quality theoretical graph of train running.

scholarly journals The Glucuronic Acid Utilization Gene Cluster from Bacillus stearothermophilus T-6

1999 ◽  
Vol 181 (12) ◽  
pp. 3695-3704 ◽  
Author(s):  
Smadar Shulami ◽  
Orit Gat ◽  
Abraham L. Sonenshein ◽  
Yuval Shoham
Keyword(s):  
Gene Cluster ◽  
Transport System ◽  
Bacillus Stearothermophilus ◽  
Glucuronic Acid ◽  
Genomic Library ◽  
Regulatory Gene ◽  
Sugar Transport ◽  
Transcriptional Unit ◽  
Transport Systems ◽  
Potential Operator

ABSTRACT A λ-EMBL3 genomic library of Bacillus stearothermophilus T-6 was screened for hemicellulolytic activities, and five independent clones exhibiting β-xylosidase activity were isolated. The clones overlap each other and together represent a 23.5-kb chromosomal segment. The segment contains a cluster of xylan utilization genes, which are organized in at least three transcriptional units. These include the gene for the extracellular xylanase, xylanase T-6; part of an operon coding for an intracellular xylanase and a β-xylosidase; and a putative 15.5-kb-long transcriptional unit, consisting of 12 genes involved in the utilization of α-d-glucuronic acid (GlcUA). The first four genes in the potential GlcUA operon (orf1, -2, -3, and -4) code for a putative sugar transport system with characteristic components of the binding-protein-dependent transport systems. The most likely natural substrate for this transport system is aldotetraouronic acid [2-O-α-(4-O-methyl-α-d-glucuronosyl)-xylotriose] (MeGlcUAXyl3). The following two genes code for an intracellular α-glucuronidase (aguA) and a β-xylosidase (xynB). Five more genes (kdgK,kdgA, uxaC, uxuA, anduxuB) encode proteins that are homologous to enzymes involved in galacturonate and glucuronate catabolism. The gene cluster also includes a potential regulatory gene, uxuR, the product of which resembles repressors of the GntR family. The apparent transcriptional start point of the cluster was determined by primer extension analysis and is located 349 bp from the initial ATG codon. The potential operator site is a perfect 12-bp inverted repeat located downstream from the promoter between nucleotides +170 and +181. Gel retardation assays indicated that UxuR binds specifically to this sequence and that this binding is efficiently prevented in vitro by MeGlcUAXyl3, the most likely molecular inducer.

scholarly journals Comparison of Direct Inoculation and Copan Transport Systems for Isolation of Neisseria gonorrhoeaefrom Endocervical Specimens

1999 ◽  
Vol 37 (11) ◽  
pp. 3583-3585 ◽  
Author(s):  
C. C. Olsen ◽  
J. R. Schwebke ◽  
W. H. Benjamin ◽  
A. Beverly ◽  
K. B. Waites
Keyword(s):  
Transport System ◽  
Low Cost ◽  
Transmitted Disease ◽  
Ease Of Use ◽  
Transport Systems ◽  
Sexually Transmitted ◽  
Sexually Transmitted Disease Clinic ◽  
Direct Inoculation ◽  
Short Time ◽  
Culture Positive

Two commercial swab transport systems, Copan Amies gel agar with and without charcoal (Copan Diagnostics, Corona, Calif.), were compared to direct inoculation onto modified Thayer-Martin medium for detection of Neisseria gonorrhoeae in 1,490 endocervical specimens obtained from women attending a sexually transmitted disease clinic. Copan swabs were held in the transport system for 24 h at room temperature prior to inoculation onto modified Thayer-Martin medium. All cultures were incubated at 35°C in 5% CO2, and bacteria were identified on the basis of Gram stain, oxidase, and biochemical reactions. Copan Amies gel agar transport system without charcoal detected 77 of 81 (95%) direct inoculation culture-positive specimens, and Copan Amies gel agar transport system with charcoal detected 53 of 56 (95%) directly inoculated culture-positive specimens. Copan Amies gel agar without charcoal inoculated after 6 h supported growth of 56 (98%) positive cultures out of only 55 directly inoculated culture-positive specimens. This study demonstrates that Copan swabs represent a reasonable alternative, providing convenience, low cost, and ease of use while still maintaining a satisfactory recovery rate of N. gonorrhoeae from clinical specimens, if specimens can be inoculated onto selective media within a relatively short time period not involving overnight shipment.

scholarly journals Archaeal Binding Protein-Dependent ABC Transporter: Molecular and Biochemical Analysis of the Trehalose/Maltose Transport System of the Hyperthermophilic Archaeon Thermococcus litoralis

1998 ◽  
Vol 180 (3) ◽  
pp. 680-689 ◽  
Author(s):  
Reinhold Horlacher ◽  
Karina B. Xavier ◽  
Helena Santos ◽  
Jocelyne DiRuggiero ◽  
Marina Kossmann ◽  
...  
Keyword(s):  
Transport System ◽  
Signal Sequence ◽  
Binding Protein ◽  
Inducible Promoter ◽  
Transport Systems ◽  
Thermococcus Litoralis ◽  
Hyperthermophilic Archaeon ◽  
E Coli ◽  
Transmembrane Segments ◽  
Maltose Transport

ABSTRACT We report the cloning and sequencing of a gene cluster encoding a maltose/trehalose transport system of the hyperthermophilic archaeonThermococcus litoralis that is homologous to themalEFG cluster encoding the Escherichia colimaltose transport system. The deduced amino acid sequence of themalE product, the trehalose/maltose-binding protein (TMBP), shows at its N terminus a signal sequence typical for bacterial secreted proteins containing a glyceride lipid modification at the N-terminal cysteine. The T. litoralis malE gene was expressed in E. coli under control of an inducible promoter with and without its natural signal sequence. In addition, in one construct the endogenous signal sequence was replaced by the E. coli MalE signal sequence. The secreted, soluble recombinant protein was analyzed for its binding activity towards trehalose and maltose. The protein bound both sugars at 85°C with aKd of 0.16 μM. Antibodies raised against the recombinant soluble TMBP recognized the detergent-soluble TMBP isolated from T. litoralis membranes as well as the products from all other DNA constructs expressed in E. coli. Transmembrane segments 1 and 2 as well as the N-terminal portion of the large periplasmic loop of the E. coli MalF protein are missing in the T. litoralis MalF. MalG is homologous throughout the entire sequence, including the six transmembrane segments. The conserved EAA loop is present in both proteins. The strong homology found between the components of this archaeal transport system and the bacterial systems is evidence for the evolutionary conservation of the binding protein-dependent ABC transport systems in these two phylogenetic branches.

scholarly journals ROLE OF TRAM TRANSIT IN FORMATION OF MAGNITOGORSK TRANSPORTATION SYSTEM (1930–1955)

2020 ◽  
Vol 17 (5) ◽  
pp. 316-325
Author(s):  
M. N. Potemkina ◽  
M. V. Gryaznov ◽  
T. G. Pashkovskaya ◽  
E. A. Timofeev
Keyword(s):  
Soviet Union ◽  
Transport System ◽  
Urban Transport ◽  
Political Life ◽  
Information Support ◽  
Transport Systems ◽  
Electric Transport ◽  
Route Network ◽  
Time Period

The article provides information about the state of Magnitogorsk electric transport during its formation. This is one of the steps to preserving the history of emergence and development of tram traffic, an attempt to outline its fundamental role in formation of the transport system, as well as in socio-economic and political life of Magnitogorsk, one of the first so called social cities of the Soviet Union. The article is structured into sections relating to expansion of the tram route network, state and development of tram fleet. The considered time period captures the years of the Great Patriotic War and is limited to the beginning of the «thaw» in the domestic political life of the Soviet state. Through systematization of documentary evidence, the fundamental role of tram traffic in formation of the transport system of Magnitogorsk for the studied time period is determined. This should contribute to development of information support for research on the historical patterns of formation of urban transport systems in the period of industrialization.This issue offers the first part of the article.

scholarly journals Women’s entrepreneurship policy: a 13 nation cross-country comparison

2017 ◽  
Vol 9 (3) ◽  
pp. 206-228 ◽  
Author(s):  
Colette Henry ◽  
Barbara Orser ◽  
Susan Coleman ◽  
Lene Foss
Keyword(s):  
Policy Development ◽  
Methodological Approach ◽  
Future Research ◽  
Entrepreneurship Policy ◽  
Policy Makers ◽  
Content Type ◽  
Policy Practice ◽  
Women’S Entrepreneurship ◽  
The Status ◽  
Women's Entrepreneurship

Purpose Government attention to women’s entrepreneurship has increased in the past two decades; however, there are few cross-cultural studies to inform policy development. This paper aims to draw on gender and institutional theory to report on the status of female-focused small and medium-sized enterprises/entrepreneurship policies and to ask how – and to what extent – do women’s entrepreneurship policies differ among countries? Design/methodology/approach A common methodological approach is used to identify gaps in the policy-practice nexus. Findings The study highlights countries where policy is weak but practice is strong, and vice versa. Research limitations/implications The study’s data were restricted to policy documents and observations of practices and initiatives on the ground. Practical implications The findings have implications for policy makers in respect of support for women’s entrepreneurship. Recommendations for future research are advanced. Originality/value The paper contributes to extant knowledge and understanding about entrepreneurship policy, specifically in relation to women’s entrepreneurship. It is also one of the few studies to use a common methodological approach to explore and compare women’s entrepreneurship policies in 13 countries.

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