scholarly journals Determining impact level of low material supply into delivery times of web servers

2019 ◽  
pp. 18-25
Author(s):  
Velia Herminia Castillo-Pérez ◽  
Lorena Ivonne Sanchez-Eguiarte
Keyword(s):  
Solid State ◽  
Delivery Time ◽  
Web Servers ◽  
Material Supply ◽  
Delivery Times ◽  
Data Analyses ◽  
Material Cost ◽  
Alternative Product ◽  
Operations Systems

Objective: To determine materials shortage to manufacture web servers, establishing impact level of low supply material into delivery time promised to customers. Methodology, data analyses showed: greatest shortage, suppliers they belong to, how many orders that fail delivery time to customer are due to lack of materials for its manufacture; also how long it takes for each material to arrive, material cost, server’s quantity impacted, profit impact of each server, old orders timing, reasons for each material missed. When analyzing by commercialized server type: customer delivery goals, materials required to manufacture; we found that most orders that do not accomplish delivery time to customers are affected by high value materials shortage; being solid-state drivers (SSD) the greatest shortage. From January 2016 to 2018, material shortage went from 1275 units per month to 2985. The main reason for current shortage is worldwide shortage, as well as disconnection between sales and operations systems. Contribution, communication between operations and sales system was automated; sales department has access to material availability to manufacture products offered to customer, enabling them to communicate accurate delivery times to customer, also to give alternative product to shorter delivery times in material required to manufacture products offered.

scholarly journals 3/2-approximation algorithm for a single machine scheduling problem

2021 ◽  
Vol 17 (3) ◽  
pp. 240-253
Author(s):  
Natalia S. Grigoreva ◽  
Keyword(s):  
Approximation Algorithm ◽  
Optimization Problem ◽  
Single Machine Scheduling ◽  
Release Time ◽  
Scheduling Problem ◽  
Delivery Time ◽  
Scheduling Problems ◽  
Delivery Times ◽  
Jobshop Scheduling ◽  
Single Processor

The problem of minimizing the maximum delivery times while scheduling tasks on a single processor is a classical combinatorial optimization problem. Each task ui must be processed without interruption for t(ui) time units on the machine, which can process at most one task at time. Each task uw; has a release time r(ui), when the task is ready for processing, and a delivery time g(ui). Its delivery begins immediately after processing has been completed. The objective is to minimize the time, by which all jobs are delivered. In the Graham notation this problem is denoted by 1|rj,qi|Cmax, it has many applications and it is NP-hard in a strong sense. The problem is useful in solving owshop and jobshop scheduling problems. The goal of this article is to propose a new 3/2-approximation algorithm, which runs in O(n log n) times for scheduling problem 1|rj.qi|Cmax. An example is provided which shows that the bound of 3/2 is accurate. To compare the effectiveness of proposed algorithms, random generated problems of up to 5000 tasks were tested.

scholarly journals Assessments of heavy lift UAV quadcopter drone to support COVID 19 vaccine cold chain delivery for indigenous people in remote areas in South East Asia

2021 ◽  
Author(s):  
Andrio Adwibowo
Keyword(s):  
East Asia ◽  
Indigenous People ◽  
Storage Temperature ◽  
Vaccine Delivery ◽  
Cold Chain ◽  
South East Asia ◽  
Delivery Time ◽  
Delivery Times ◽  
Heavy Lift ◽  
Operational Time

AbstractVaccine delivery is one important aspect need to be strengthened within health systems. One of the main challenges in COVID 19 vaccine delivery is how to cover indigenous population in remote and isolated forests in South East Asia. Another issue in COVID 19 cold chain delivery is requirement for a carrier that can maintain the suitable storage temperature. Related to this condition, COVID 19 vaccine should be delivered using heavy vaccine cooler box and this demand delivery system equipped with heavy lift capacity. In here, this study proposes and assess the potential used of heavy lift UAV quadcopter to expand the COVID 19 vaccine delivery to indigenous people living in village that impeded by rugged terrain. The landscape and terrain analysis show that access to the villages was dominated by 15%-45% slopes and the available access is only 1.5 m width trail. To transport 500 vials with 10 kg carrier along 2 km trail, it requires 2 persons to walk for 1 hour. By using drone, a straight line route with a length of 1.5 km can be developed. There were at least 3 drone types were available commercially to lift 10 kg load and several drones with payload capacity below 10 kg. For carrying 100 vials to village using drones, it is estimated the required delivery time was 1.23-1.38 minutes. Around 1.57-1.66 minute delivery times were required to transport 250 vials. For carrying the maximum and full loads of 500 vials or equals to 10 kg load, a drone requires in average of 3.13 minute delivery times. This required drone delivery time is significantly below the required time by walking that almost 1 hour. Drones were limited by flight operational times. Whereas all required delivery times for each drone assessed in this study were still below the drone operational time. The lowest drone operational time was 16 minutes and this is still higher than the time required for a drone to deliver the vaccine. Considering the effectiveness and anticipating vaccine vaccination, UAV quadcopter drone is a feasible option to support COVID 19 vaccine delivery to reach indigenous people in isolated areas.

scholarly journals Isotopic evidence for volatile replenishment of the Moon during the Late Accretion

2019 ◽  
Vol 6 (6) ◽  
pp. 1247-1254 ◽  
Author(s):  
Yanhao Lin ◽  
Wim van Westrenen
Keyword(s):  
Dynamic Models ◽  
Temporal Evolution ◽  
Carbonaceous Chondrite ◽  
Isotopic Ratios ◽  
Delivery Time ◽  
The Moon ◽  
Lunar Interior ◽  
Delivery Times ◽  
Lunar Samples ◽  
Water Contents

AbstractThe traditional view of a dry, volatile-poor Moon has been challenged by the identification of water and other volatiles in lunar samples, but the volatile budget delivery time(s), source(s) and temporal evolution remain poorly constrained. Here we show that hydrogen and chlorine isotopic ratios in lunar apatite changed significantly during the Late Accretion (LA, 4.1–3.8 billion years ago). During this period, deuterium/hydrogen ratios in the Moon changed from initial carbonaceous-chondrite-like values to values consistent with an influx of ordinary-chondrite-like material and pre-LA elevated δ37Cl values drop towards lower chondrite-like values. Inferred pre-LA lunar interior water contents are significantly lower than pristine values suggesting degassing, followed by an increase during the LA. These trends are consistent with dynamic models of solar-system evolution, suggesting that the Moon's (and Earth's) initial volatiles were replenished ∼0.5 Ga after their formation, with their final budgets reflecting a mixture of sources and delivery times.

A Procedure for Rapid Issue of Red Cells for Emergency Use

2005 ◽  
Vol 129 (4) ◽  
pp. 492-496
Author(s):  
Richard B. Weiskopf ◽  
Mary Webb ◽  
Deena Stangle ◽  
Gunter Klinbergs ◽  
Pearl Toy
Keyword(s):  
Red Blood Cells ◽  
Operating Room ◽  
Blood Cells ◽  
Blood Bank ◽  
Red Cells ◽  
University Hospital ◽  
Delivery Time ◽  
Delivery Times ◽  
The Times ◽  
Time Required

Abstract Context.—A College of American Pathologists Q-Probe revealed that the median turnaround times for emergency requests for red blood cells from the operating room were 30 minutes to release of cells from the blood bank and 34 minutes to delivery to the operating room. These times may not be adequate to permit the red cells to provide sufficiently rapid delivery of oxygen in massively bleeding patients. Objective.—To improve the time from emergency request for red cells to delivery to the operating room. Design.—A new emergency issue program was implemented for only the operating rooms; emergency issue to all other hospital locations remained unchanged. Six units of group O Rh-negative red blood cells (RBCs) are maintained in the blood bank in a separate basket with transfusion forms containing the unit numbers and expiration dates and a bag with one blood tubing segment from each unit. The times to issue and to delivery to the operating room suite were compared with time to issue of 2 group O Rh-negative RBCs for other hospital locations using the older system during the same time period and with the time to issue of 2 units to all other hospital locations during the preceding 2 years. Setting.—A university hospital. Main Outcome Measures.—Time between emergency request for red cells and delivery to the operating room. Results.—The time between blood bank notification and arrival in the operating room of the 6 units of RBCs was significantly shorter than the time required to just issue (not including delivery time) 2 units of RBCs to other hospital locations. With the new procedure, 82% of units issued reached the operating room within 2 minutes of request, 91% arrived within 3 minutes, and 100% arrived within 4 minutes. These percentages are significantly higher than those for only issue of blood (without delivery) using the older issuing procedure for all hospital locations during the previous 2 years (37%, 49%, and 66%, respectively; P = .007, .009, and .02, respectively) and for other locations during the same 7-month period (29%, 46%, and 73%, respectively; P = .004, .01, and .09, respectively). Time (mean [95% confidence interval]) from blood bank notification to delivery of RBCs to the operating room suite (2.1 [1.6–2.6] minutes, of which approximately 50–60 seconds is attributable to delivery time) was less than issue times (not including delivery times) using the older issuing procedure for other hospital locations during the same period (4.1 [3.1–5.0] minutes; P = .007). Conclusions.—An emergency issue procedure can be used to issue several units of RBCs within 1 minute and have them delivered to the operating room within 2 minutes while maintaining sufficient controls and providing required information to satisfy patient and blood bank requirements.

Fast or free shipping options in online and Omni-channel retail? The mediating role of uncertainty on satisfaction and purchase intentions

2017 ◽  
Vol 28 (4) ◽  
pp. 1099-1122 ◽  
Author(s):  
Siqi Ma
Keyword(s):  
Customer Satisfaction ◽  
Service Quality ◽  
Purchase Intentions ◽  
Delivery Time ◽  
Content Type ◽  
Mediating Role ◽  
Logistics Service ◽  
Delivery Times ◽  
Free Shipping ◽  
Logistics Service Quality

Purpose The purpose of this paper is to investigate the effect of a dimension of logistics service quality (delivery time) interacting with shipping charges and purchase importance on customer satisfaction and purchase intentions in an e-commerce context. Uncertainty in terms of perceived ambiguity and perceived riskiness is shown to be the theoretical mechanism that plays a mediating role in the relationships between delivery time and customer satisfaction, as well as between delivery time and purchase intentions. Design/methodology/approach This study used a scenario-based role playing experiment. Three variables are manipulated in the design of the study – delivery time, shipping charges, and purchase importance. Participant responses (n=360) were collected through Amazon Mechanical Turk with perceptual measures. Findings Results indicated that increased delivery time significantly increased customers’ perceived ambiguity and perceived riskiness which reduced satisfaction as well as negatively impacted purchase intentions. Further, free shipping reduced customers’ perceived ambiguity when delivery time was lengthy, but strengthened the perception of ambiguity when the delivery time was short. Originality/value This paper sheds light on how a dimension of logistics service quality (delivery time) interacts with shipping charges and purchase importance to impact customer satisfaction and purchase intentions. It introduces uncertainty in the form of perceived ambiguity and perceived riskiness, to the logistics service literature as the mechanism that can explain how delivery time interacting with shipping charges and purchase importance impact customer satisfaction and purchase intentions. The implications for online retailers are that they should display separate shipping charges for shorter delivery times but for longer delivery times they should display a total price for the product which includes the shipping cost. Also when the purchase is important to the customer, they should offer shorter shipping time choices if they want to increase customer satisfaction.

scholarly journals Chemical Warfare Agent Simulants in Gamble’s Fluid: Is the Fluid Toxic? Can It Be Made Safer by Inclusion of Solid Nanocrystalline Metal Oxides?

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Dennis Karote ◽  
Brandon Walker ◽  
Huaien Dai ◽  
Ramaswamy Krishnamoorthi ◽  
Janis Voo ◽  
...  
Keyword(s):  
Solid State ◽  
Metal Oxides ◽  
Degradation Product ◽  
Chemical Warfare Agent ◽  
Degradation Pathway ◽  
Chemical Warfare ◽  
Nanocrystalline Metal ◽  
Condensation Products ◽  
Data Analyses ◽  
Hydrolysis Of

The reactions of chemical warfare agent simulants, 2-chloroethyl ethyl sulfide (2-CEES) and di-i-propyl fluoro phosphate (DFP), in fluids have been investigated. Data analyses confirm the major degradation pathway to be hydrolysis of 2-CEES to 2-hydroxyethyl ethyl sulfide, along with minor self-condensation products. Among the three fluids examined, 2-CEES degradation was the fastest in Gamble’s fluid during a 96 h period. Upon addition of Exceptional Hazard Attenuation Materials (EHAMs) to 2-CEES containing Gamble’s fluid, degradation was generally improved during the first 24 h period. The 96 h outcome was similar for fluid samples with or without EHAM 2 and EHAM 4. EHAM 1-added fluid contained only one degradation product, 2-nitroethyl ethyl sulfide. DFP degradation was the slowest in Gamble’s fluid, but was enhanced by the addition of EHAMs. FTIR and solid state31P NMR confirm the destructive adsorption of 2-CEES and DFP by the EHAMs. The results collectively demonstrate that 2-CEES and DFP decompose to various extents in Gamble’s fluid over a 96 h period but the fluid still contains a considerable amount of intact simulant. EHAM 1 appears to be promising for 2-CEES and DFP mitigation while EHAM 2 and EHAM 4 work well for early on concentration reduction of 2-CEES and DFP.

scholarly journals Branch Less, Cut More and Schedule Jobs with Release and Delivery Times on Uniform Machines

Mathematics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 633
Author(s):  
Nodari Vakhania ◽  
Frank Werner
Keyword(s):  
Parallel Machines ◽  
Polynomial Time Algorithm ◽  
Time Algorithm ◽  
Delivery Time ◽  
Processing Times ◽  
Delivery Times ◽  
Uniform Machines ◽  
Complexity Status ◽  
Algorithmic Framework ◽  
Job Delivery

We consider the problem of scheduling n jobs with identical processing times and given release as well as delivery times on m uniform machines. The goal is to minimize the makespan, i.e., the maximum full completion time of any job. This problem is well-known to have an open complexity status even if the number of jobs is fixed. We present a polynomial-time algorithm for the problem which is based on the earlier introduced algorithmic framework blesscmore (“branch less and cut more”). We extend the analysis of the so-called behavior alternatives developed earlier for the version of the problem with identical parallel machines and show how the earlier used technique for identical machines can be extended to the uniform machine environment if a special condition on the job parameters is imposed. The time complexity of the proposed algorithm is O(γm2nlogn), where γ can be either n or the maximum job delivery time qmax. This complexity can even be reduced further by using a smaller number κ<n in the estimation describing the number of jobs of particular types. However, this number κ becomes only known when the algorithm has terminated.

scholarly journals A Novel Dynamic and Fuzzy Value Stream Mapping (DFVSM): System Dynamics and Fuzzy Logic Integration

2021 ◽  
Vol 41 (2) ◽  
pp. e84539
Author(s):  
Roberto Baeza Serrato
Keyword(s):  
Fuzzy Logic ◽  
System Dynamics ◽  
Lead Time ◽  
Real Data ◽  
Value Stream Mapping ◽  
Delivery Time ◽  
Value Stream ◽  
Delivery Times ◽  
Efficiency And Effectiveness ◽  
Time Planning

Value stream mapping (VSM) is a method to identify waste and activities that do not add value. One of its main disadvantages is that the parameters used in the process and material flows are deterministic. The motivation of this research is to improve the reliability of the estimation of the lead time in VSM, transitioning from a static model to a dynamic model that incorporates uncertainty and imprecision in the data, as well as to develop a novel dynamic and fuzzy value stream mapping (DFVSM) based on integrating system dynamics and fuzzy logic. One of the main contributions of this research is to develop a fuzzy system in the same system dynamics interface that incorporates uncertainty and vagueness to the efficiency and effectiveness percentage variable (OEE%) to increase the reliability of the delivery time planning. The stages of DFVSM are explicitly described and applied to real data for a textile company in southern Guanajuato. A sensitivity analysis of the proposed model was integrated which identifies the critical factors for the delivery of the order, and achievable times were proposed for the delivery times of the supplier and the client, thus reducing the expected delivery time by 28%. One of the relevant conclusions of this work is that, to plan the lead time of an order, the uncertainty of the main parameters such as supplier and customer shipping times be considered to satisfy the customer.

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