scholarly journals Optimizing Sample Design for Approximate Query Processing

2013 ◽  
Vol 3 (4) ◽  
pp. 1-21
Author(s):  
Philipp Rösch ◽  
Wolfgang Lehner

The rapid increase of data volumes makes sampling a crucial component of modern data management systems. Although there is a large body of work on database sampling, the problem of automatically determine the optimal sample for a given query remained (almost) unaddressed. To tackle this problem the authors propose a sample advisor based on a novel cost model. Primarily designed for advising samples of a few queries specified by an expert, the authors additionally propose two extensions of the sample advisor. The first extension enhances the applicability by utilizing recorded workload information and taking memory bounds into account. The second extension increases the effectiveness by merging samples in case of overlapping pieces of sample advice. For both extensions, the authors present exact and heuristic solutions. Within their evaluation, the authors analyze the properties of the cost model and demonstrate the effectiveness and the efficiency of the heuristic solutions with a variety of experiments.

2020 ◽  
pp. 77-90
Author(s):  
V.D. Gerami ◽  
I.G. Shidlovskii

The article presents a special modification of the EOQ formula and its application to the accounting of the cargo capacity factor for the relevant procedures for optimizing deliveries when renting storage facilities. The specified development will allow managers to take into account the following process specifics in the format of a simulated supply chain when managing inventory. First of all, it will allow considering the most important factor of cargo capacity when optimizing stocks. Moreover, this formula will make it possible to find the optimal strategy for the supply of goods if, also, it is necessary to take into account the combined effect of several factors necessary for practice, which will undoubtedly affect decision-making procedures. Here we are talking about the need for additional consideration of the following essential attributes of the simulated cash flow of the supply chain: 1) time value of money; 2) deferral of payment of the cost of the order; 3) pre-agreed allowable delays in the receipt of revenue from goods sold. Developed analysis and optimization procedures have been implemented to models of this type that are interesting and important for a business. This — inventory management systems, the format of which is related to the special concept of efficient supply. We are talking about models where the presence of the specified delays for the outgoing cash flows allows you to pay for the order and the corresponding costs of the supply chain from the corresponding revenue on the re-order interval. Accordingly, the necessary and sufficient conditions are established based on which managers will be able to identify models of the specified type. The purpose of the article is to draw the attention of managers to real opportunities to improve the efficiency of inventory management systems by taking into account these factors for a simulated supply chain.


2019 ◽  
Vol 14 (3) ◽  
pp. 160-172 ◽  
Author(s):  
Aynaz Nourani ◽  
Haleh Ayatollahi ◽  
Masoud Solaymani Dodaran

Background:Data management is an important, complex and multidimensional process in clinical trials. The execution of this process is very difficult and expensive without the use of information technology. A clinical data management system is software that is vastly used for managing the data generated in clinical trials. The objective of this study was to review the technical features of clinical trial data management systems.Methods:Related articles were identified by searching databases, such as Web of Science, Scopus, Science Direct, ProQuest, Ovid and PubMed. All of the research papers related to clinical data management systems which were published between 2007 and 2017 (n=19) were included in the study.Results:Most of the clinical data management systems were web-based systems developed based on the needs of a specific clinical trial in the shortest possible time. The SQL Server and MySQL databases were used in the development of the systems. These systems did not fully support the process of clinical data management. In addition, most of the systems lacked flexibility and extensibility for system development.Conclusion:It seems that most of the systems used in the research centers were weak in terms of supporting the process of data management and managing clinical trial's workflow. Therefore, more attention should be paid to design a more complete, usable, and high quality data management system for clinical trials. More studies are suggested to identify the features of the successful systems used in clinical trials.


2019 ◽  
Vol 14 (1) ◽  
pp. 10-23 ◽  
Author(s):  
Aynaz Nourani ◽  
Haleh Ayatollahi ◽  
Masoud Solaymani Dodaran

Background:A clinical data management system is a software supporting the data management process in clinical trials. In this system, the effective support of clinical data management dimensions leads to the increased accuracy of results and prevention of diversion in clinical trials. The aim of this review article was to investigate the dimensions of data management in clinical data management systems.Methods:This study was conducted in 2017. The used databases included Web of Science, Scopus, Science Direct, ProQuest, Ovid Medline and PubMed. The search was conducted over a period of 10 years from 2007 to 2017. The initial number of studies was 101 reaching 19 in the final stage. The final studies were described and compared in terms of the year, country and dimensions of the clinical data management process in clinical trials.Results:The research findings indicated that none of the systems completely supported the data management dimensions in clinical trials. Although these systems were developed for supporting the clinical data management process, they were similar to electronic data capture systems in many cases. The most significant dimensions of data management in such systems were data collection or entry, report, validation, and security maintenance.Conclusion:Seemingly, not sufficient attention has been paid to automate all dimensions of the clinical data management process in clinical trials. However, these systems could take positive steps towards changing the manual processes of clinical data management to electronic processes.


Author(s):  
Viktoriya Yu. Ukhanova

In the pig breeding, a large share of the production cost is accounted for by the cost of electricity and heat. Reducing energy costs is one of the important tasks of the industry. It is important to identify and study modern technologies and equipment for pig farming due to the constant increase in electricity tariffs, significant energy costs for creating and maintaining a microclimate. (Research purpose) The research purpose is in an analysis of modern available technologies and equipment for agricultural production, including pig farming, allowing to reduce the cost of production. (Materials and methods) Authors used a method for determining the standard indicators of energy consumption of energy resources in the pig industry, based on the calculation and analytical method. The article presents an analyze of automated microclimate management systems in pig breeding complexes, taking into account the individual characteristics of farms produced by OWEN. (Results and discussion) Automated microclimate management systems can improve the productivity of pig farms; reduce the cost of electrical and thermal energy, reduce the number of diseases of animal from hypothermia, high humidity or temperature in the room, feed consumption; monitor the chemical composition of the air. The article considers three options for creating a microclimate in rooms with animals, taking into account the individual characteristics of enterprises. (Conclusions) The profitability of pig production depend on the level of technical equipment of farms, automation, and the use of energy-saving technologies and equipment. The use of innovations in agricultural production makes it possible to increase labor productivity up to three times, and savings due to reduced feed costs can reach several million rubles a year.


2019 ◽  
Vol 944 (2) ◽  
pp. 46-56
Author(s):  
S.A. Yamashkin ◽  
A.A. Yamashkin ◽  
O.A. Zarubin

The article is devoted to a detailed analysis of the problem of designing graphic geoportal interfaces. The authors formulated the basic points for solving problems in this field, having given the rationale and detailed description of each of them. The emphasis is made on the flexible arrangement of the design and development of interfaces, aiming at the future realities, at the human centricity of the interface design process, at the need for cross-platform adaptive web interfaces, at the preference to use proprietary and third-party software modules over the implementation of spatial data management systems. Lists of basic functional and quality requirements for graphical interfaces of geoportals are given. The geoportal “Natural and cultural heritage of Mordovia” is presented as an illustrative example of the various implementation of graphical user web interfaces. An experimental assessment of the effectiveness of measures to improve geoportal graphical interfaces is given. It is shown that properly over-thought interfaces of geoportal systems can contribute to solving various kinds of problems in many fields.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Fulgence Niyibitegeka ◽  
Arthorn Riewpaiboon ◽  
Sitaporn Youngkong ◽  
Montarat Thavorncharoensap

Abstract Background In 2016, diarrhea killed around 7 children aged under 5 years per 1000 live births in Burundi. The objective of this study was to estimate the economic burden associated with diarrhea in Burundi and to examine factors affecting the cost to provide economic evidence useful for the policymaking about clinical management of diarrhea. Methods The study was designed as a prospective cost-of-illness study using an incidence-based approach from the societal perspective. The study included patients aged under 5 years with acute non-bloody diarrhea who visited Buyenzi health center and Prince Regent Charles hospital from November to December 2019. Data were collected through interviews with patients’ caregivers and review of patients’ medical and financial records. Multiple linear regression was performed to identify factors affecting cost, and a cost model was used to generate predictions of various clinical and care management costs. All costs were converted into international dollars for the year 2019. Results One hundred thirty-eight patients with an average age of 14.45 months were included in this study. Twenty-one percent of the total patients included were admitted. The average total cost per episode of diarrhea was Int$109.01. Outpatient visit and hospitalization costs per episode of diarrhea were Int$59.87 and Int$292, respectively. The costs were significantly affected by the health facility type, patient type, health insurance scheme, complications with dehydration, and duration of the episode before consultation. Our model indicates that the prevention of one case of dehydration results in savings of Int$16.81, accounting for approximately 11 times of the primary treatment cost of one case of diarrhea in the community-based management program for diarrhea in Burundi. Conclusion Diarrhea is associated with a substantial economic burden to society. Evidence from this study provides useful information to support health interventions aimed at prevention of diarrhea and dehydration related to diarrhea in Burundi. Appropriate and timely care provided to patients with diarrhea in their communities and primary health centers can significantly reduce the economic burden of diarrhea. Implementing a health policy to provide inexpensive treatment to prevent dehydration can save significant amount of health expenditure.


Sign in / Sign up

Export Citation Format

Share Document