Optimizing One-time and Continuous Subgraph Queries using Worst-case Optimal Joins

2021 ◽  
Vol 46 (2) ◽  
pp. 1-45
Author(s):  
Amine Mhedhbi ◽  
Chathura Kankanamge ◽  
Semih Salihoglu
Keyword(s):  
Dynamic Programming ◽  
Continuous Queries ◽  
Query Evaluation ◽  
Query Execution ◽  
Worst Case ◽  
The Core ◽  
Adaptive Technique ◽  
Subgraph Query ◽  
The Cost ◽  
Core Problem

We study the problem of optimizing one-time and continuous subgraph queries using the new worst-case optimal join plans. Worst-case optimal plans evaluate queries by matching one query vertex at a time using multiway intersections. The core problem in optimizing worst-case optimal plans is to pick an ordering of the query vertices to match. We make two main contributions: 1. A cost-based dynamic programming optimizer for one-time queries that (i) picks efficient query vertex orderings for worst-case optimal plans and (ii) generates hybrid plans that mix traditional binary joins with worst-case optimal style multiway intersections. In addition to our optimizer, we describe an adaptive technique that changes the query vertex orderings of the worst-case optimal subplans during query execution for more efficient query evaluation. The plan space of our one-time optimizer contains plans that are not in the plan spaces based on tree decompositions from prior work. 2. A cost-based greedy optimizer for continuous queries that builds on the delta subgraph query framework. Given a set of continuous queries, our optimizer decomposes these queries into multiple delta subgraph queries, picks a plan for each delta query, and generates a single combined plan that evaluates all of the queries. Our combined plans share computations across operators of the plans for the delta queries if the operators perform the same intersections. To increase the amount of computation shared, we describe an additional optimization that shares partial intersections across operators. Our optimizers use a new cost metric for worst-case optimal plans called intersection-cost . When generating hybrid plans, our dynamic programming optimizer for one-time queries combines intersection-cost with the cost of binary joins. We demonstrate the effectiveness of our plans, adaptive technique, and partial intersection sharing optimization through extensive experiments. Our optimizers are integrated into GraphflowDB.

In a word, I’ve been there

2019 ◽  
pp. 246-256
Author(s):  
A. K. Zholkovsky
Keyword(s):  
The State ◽  
Female Characters ◽  
Political Situation ◽  
The Core ◽  
The Relationship ◽  
Core Problem ◽  
Typical Solution

In his article, A. Zholkovsky discusses the contemporary detective mini-series Otlichnitsa [A Straight-A Student], which mentions O. Mandelstam’s poem for children A Galosh [Kalosha]: more than a fleeting mention, this poem prompts the characters and viewers alike to solve the mystery of its authorship. According to the show’s plot, the fact that Mandelstam penned the poem surfaces when one of the female characters confesses her involvement in his arrest. Examining this episode, Zholkovsky seeks structural parallels with the show in V. Aksyonov’s Overstocked Packaging Barrels [Zatovarennaya bochkotara] and even in B. Pasternak’s Doctor Zhivago [Doktor Zhivago]: in each of those, a member of the Soviet intelligentsia who has developed a real fascination with some unique but unattainable object is shocked to realize that the establishment have long enjoyed this exotic object without restrictions. We observe, therefore, a typical solution to the core problem of the Soviet, and more broadly, Russian cultural-political situation: the relationship between the intelligentsia and the state, and the resolution is not a confrontation, but reconciliation.

Emotional Choices

2018 ◽  
Author(s):  
Robin Markwica
Keyword(s):  
Decision Making ◽  
Choice Behavior ◽  
Choice Theory ◽  
Cuban Missile Crisis ◽  
Coercive Diplomacy ◽  
The Core ◽  
Present Book ◽  
Action Model ◽  
The Cost ◽  
Dynamic Interplay

In coercive diplomacy, states threaten military action to persuade opponents to change their behavior. The goal is to achieve a target’s compliance without incurring the cost in blood and treasure of military intervention. Coercers typically employ this strategy toward weaker actors, but targets often refuse to submit and the parties enter into war. To explain these puzzling failures of coercive diplomacy, existing accounts generally refer to coercers’ perceived lack of resolve or targets’ social norms and identities. What these approaches either neglect or do not examine systematically is the role that emotions play in these encounters. The present book contends that target leaders’ affective experience can shape their decision-making in significant ways. Drawing on research in psychology and sociology, the study introduces an additional, emotion-based action model besides the traditional logics of consequences and appropriateness. This logic of affect, or emotional choice theory, posits that target leaders’ choice behavior is influenced by the dynamic interplay between their norms, identities, and five key emotions, namely fear, anger, hope, pride, and humiliation. The core of the action model consists of a series of propositions that specify the emotional conditions under which target leaders are likely to accept or reject a coercer’s demands. The book applies the logic of affect to Nikita Khrushchev’s decision-making during the Cuban missile crisis in 1962 and Saddam Hussein’s choice behavior in the Gulf conflict in 1990–91, offering a novel explanation for why coercive diplomacy succeeded in one case but not in the other.

scholarly journals Query Rewriting for Incremental Continuous Query Evaluation in HIFUN

Algorithms ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 149
Author(s):  
Petros Zervoudakis ◽  
Haridimos Kondylakis ◽  
Nicolas Spyratos ◽  
Dimitris Plexousakis
Keyword(s):  
Query Optimization ◽  
Query Language ◽  
Computational Cost ◽  
Continuous Queries ◽  
Continuous Query ◽  
Query Rewriting ◽  
Query Evaluation ◽  
Clear Separation ◽  
Complete Dataset ◽  
High Level

HIFUN is a high-level query language for expressing analytic queries of big datasets, offering a clear separation between the conceptual layer, where analytic queries are defined independently of the nature and location of data, and the physical layer, where queries are evaluated. In this paper, we present a methodology based on the HIFUN language, and the corresponding algorithms for the incremental evaluation of continuous queries. In essence, our approach is able to process the most recent data batch by exploiting already computed information, without requiring the evaluation of the query over the complete dataset. We present the generic algorithm which we translated to both SQL and MapReduce using SPARK; it implements various query rewriting methods. We demonstrate the effectiveness of our approach in temrs of query answering efficiency. Finally, we show that by exploiting the formal query rewriting methods of HIFUN, we can further reduce the computational cost, adding another layer of query optimization to our implementation.

scholarly journals A Constrained Markovian Diffusion Model for Controlling the Pollution Accumulation

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1466
Author(s):  
Beatris Adriana Escobedo-Trujillo ◽  
José Daniel López-Barrientos ◽  
Javier Garrido-Meléndez
Keyword(s):  
Dynamic Programming ◽  
Dirichlet Problem ◽  
Stochastic Control ◽  
Finite Time ◽  
Time Horizon ◽  
Closed Loop ◽  
Programming Techniques ◽  
Pollution Accumulation ◽  
Finite Time Horizon ◽  
The Cost

This work presents a study of a finite-time horizon stochastic control problem with restrictions on both the reward and the cost functions. To this end, it uses standard dynamic programming techniques, and an extension of the classic Lagrange multipliers approach. The coefficients considered here are supposed to be unbounded, and the obtained strategies are of non-stationary closed-loop type. The driving thread of the paper is a sequence of examples on a pollution accumulation model, which is used for the purpose of showing three algorithms for the purpose of replicating the results. There, the reader can find a result on the interchangeability of limits in a Dirichlet problem.

Contour Extraction of Cerebrovascular Based on Maximum Optimization Cost

2011 ◽  
Vol 204-210 ◽  
pp. 1415-1418
Author(s):  
De Jiang Zhang ◽  
Na Na Dong ◽  
Xiao Mei Lin
Keyword(s):  
Dynamic Programming ◽  
Blood Vessel ◽  
High Efficiency ◽  
High Accuracy ◽  
Differential Method ◽  
Cost Curve ◽  
Contour Extraction ◽  
Target Image ◽  
The Cost ◽  
Conventional Algorithm

By studying the conventional algorithm of contour extraction, a new method of contour extraction in blood vessel of brain is proposed based on the MOC maximum optimization cost. First of all, the theory computes the gray differential of the image by conventional differential method to build the cost space. Then, by using dynamic programming theory, the maximum optimization cost curve in the space is extracted to serve as the specific cerebrovascular profile. The experiments show that this method ensures high efficiency in extracting cerebrovascular contour and a high accuracy in positioning cerebrovascular contour, and it diminishes the target image ambiguity caused by noise to improve the anti-interference ability of Contour extraction.

PERANCANGAN IDENTITAS VISUAL REBRANDING CITRA PERUSAHAAN CEMARA CERAMICS (DESIGN OF CEMARA CERAMICS VISUAL REBRANDING IDENTITY)

2021 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Anak Agung Ngurah Gede Marhendra ◽  
Agung Eko Budiwaspada ◽  
Sangayu Ketut Laksemi Nilotama
Keyword(s):  
Design Thinking ◽  
Corporate Identity ◽  
Corporate Image ◽  
Visual Design ◽  
Stage Design ◽  
The Core ◽  
Visual Identity ◽  
The Creation ◽  
Strategy Design ◽  
Core Problem

<p>Abstract Design of Cemara Ceramics Visual Rebranding Identity aims to produce a concept strategy and visual rebranding of the Cemara Ceramics company and produce a Cemara Ceramics rebranding visual identity design in order to encourage the creation of a new identity image. The method in this design uses a 5-stage Design Thinking approach, namely Empathize, Define, Ideate, Prototype and Test. The result achieved is the design of the new Cemara Ceramics corporate identity. With the use of the design thinking method in this research, various problems related to the company image of Cemara Ceramics can be found. The core problem obtained is how to design a strategy and concept of visual identity rebranding to encourage the creation of a new corporate image of Cemara Ceramics.</p><p>Keywords: visual rebranding identity, concept strategy, design thinking</p><p>Abstrak Perancangan Identitas Visual Rebranding Citra Perusahaan Cemara Ceramics ini bertujuan untuk menghasilkan strategi konsep dan visual rebranding perusahaan Cemara Ceramics serta menghasilkan rancangan identitas visual rebranding Cemara Ceramics dalam rangka mendorong terciptanya citra identitas yang baru. Metode dalam perancangan ini menggunakan pendekatan 5 tahapan Design Thinking yaitu Empathize, Define, Ideate, Prototype dan Test. Hasil yang dicapai yaitu rancangan corporate identity Cemara Ceramics yang baru. Dengan adanya penggunaan metode design thinking pada penelitian ini dapat menemukan berbagai permasalahan terkait citra perusahaan Cemara Ceramics. Permasalahan inti yang didapat yaitu mengenai bagaimana merancang strategi dan konsep identitas visual rebranding untuk mendorong terciptanya citra baru perusahaan Cemara Ceramics.</p><p>Kata kunci: identitas visual rebranding, strategi konsep dan visual, design thinking</p>

STUDY ON THE PROCESS OF RAPESEED HULLING BY THE IMPACT

2019 ◽  
Author(s):  
А.О. РЕНЗЯЕВ ◽  
О.П. РЕНЗЯЕВ ◽  
С.Н. КРАВЧЕНКО ◽  
Р.В. КРЮК
Keyword(s):  
Rotational Speed ◽  
Calculated Data ◽  
Quality Characteristics ◽  
Complete Separation ◽  
Edible Oil ◽  
Siberian Region ◽  
The Core ◽  
The Cost ◽  
The Impact

Исследованы прочностные и физико-механические свойства оболочки рапса с точки зрения ее разрушения и удаления. Установлено, что наиболее рациональным является двухстадийный способ обрушивания: 1-я стадия – на вальцовых мельницах, 2-я – на центробежной обрушивающей машине. Определены параметры центробежной обрушивающей машины для обеспечения минимальной необходимой линейной скорости 10,81 м/с: угол наклона отбойной пластины (90 ± 2)°, частота вращения барабана (2400 ± 150) об/мин. Установлено, что правильно подобранные условия и угол, под которым происходит удар, позволяют значительно снизить количество не до конца обрушенного семени и содержание расколотого ядра. При этом при свободном ударе об отбойную пластину под углом, отличным от 88–91°, или подаче недостаточно равномерного потока семян значительно увеличивается содержание необрушенных семян. На разрушение 1 кг семян необходимо затратить 58,45 Дж. Таким образом, по расчетным данным, для семян рапса диаметром 1,5 мм частота вращения барабана должна находиться в диапазоне от 2221 до 2565 об/мин при ударе семени под углом 90°. Диаметр семян рапса, выращиваемого в Сибирском регионе, составляет от 0,8 до 1,8 мм. Установлено, что подсушивание семян рапса в течение 30–40 с при температуре 100°С позволяет увеличить эффективность разрушения оболочки до полного ее отделения от ядра рапса. Представленные результаты позволяют повысить качество очистки семян рапса от оболочки и улучшить качественные характеристики получаемого масла, облегчить последующие технологические процессы получения пищевого масла, снизить затраты на рафинацию и дезодорацию на 2%. The strength and physico-mechanical properties of the shell of rapeseed in terms of its destruction and removal are investigated. It is established that the most rational is a two-stage method of seed hulling: the 1st stage – on roller mills, the 2nd – on a centrifugal hulling machine. The parameters of the centrifugal hulling machine to provide the minimum required linear speed of 10,81 m/s are defined: the angle of inclination of the turnback plate (90 ± 2)°, the rotational speed of drum (2400 ± 150) RPM. It is established that the correctly selected conditions and the angle at which the impact occurs, can significantly reduce the amount is not completely hulling seed and the substance of the split nucleus. At the same time, with a free impact on the turnback plate at an angle different from 88–91°, or the supply of an insufficiently uniform flow of seeds, the content is not completely hulling seed increases significantly. On hulling of 1 kg of seeds it is necessary to spend 58,45 J. Thus, according to the calculated data, for rape seeds with a diameter of 1,5 mm, the rotational speed of drum should be in the range from 2221 to 2565 RPM when the seed is struck at an angle of 90°. The diameter of rapeseed grown in the Siberian region ranges from 0,8 to 1,8 mm. It was found that drying of rapeseed for 30–40 s at a temperature of 100°C, can increase the efficiency of destruction of the shell to its complete separation from the core of rapeseed. The presented results make it possible to improve the quality of cleaning of rape seeds from the shell and improve the quality characteristics of the obtained oil, facilitate the subsequent technological processes of obtaining edible oil, reduce the cost of refining and deodorization by 2%.

scholarly journals Mind mapping as a tool of teaching English vocabulary at transport university

2021 ◽  
Vol 295 ◽  
pp. 05021
Author(s):  
Oksana Marunevich ◽  
Elmira Shefieva ◽  
Olga Bessarabova
Keyword(s):  
Educational Process ◽  
Control Group ◽  
Teaching English ◽  
Mind Mapping ◽  
New Words ◽  
The Core ◽  
Mind Maps ◽  
The Given ◽  
Core Problem ◽  
Experimental Group

The core problem of teaching English as a second language at transport university is students’ poor knowledge of vocabulary. Current solutions to the given problem such as providing word explanations and repetitive practices are ineffective. We strongly believe that the mindmapping technique proposed by Tony Buzan as a note-taking method is a novel, yet an extremely potent tool that aids students in enlarging their professional word stock by associating new vocabulary to their existing knowledge using colors, images, symbols, etc. As might have been expected, the findings of our study point towards the idea that the strong visual appeal of mind maps created by easy-to-use software boosted the educational process and helped students of the experimental group memorize more new words in contrast to students of the control group.

scholarly journals Å balansere mellom barnevernets prinsipper

2020 ◽  
pp. 49-65
Author(s):  
Grethe Netland
Keyword(s):  
Child Protection ◽  
Reflective Equilibrium ◽  
Best Interest ◽  
Moral Intuitions ◽  
The Core ◽  
Child Protection Service ◽  
Biological Principle ◽  
The Cost

The focus of this chapter is the potential conflicts between the values that are basic in the work of Norwegian child protection service. Such values are expressed in principles that serve as guidelines for judgement and decisions in the field. ‘The best interest of the child’ principle is held to be grounding. The ‘mildest intervention’ principle and the ‘biological’ principle are normally held to be at the core of how the best interest of the child is to be understood. Important in child protection work, is to interpret the principles, weigh them, and consider what implications they should have in specific cases. I argue that if, for some reason, one principle is ascribed too much weigh on the cost of others, the solution for the child might not be in its best interest. I highlight the importance of not only weighing the principles against each other, but also creating a coherent balance between the principles, people’s moral intuitions and the actual practices of the service. To this end, I suggest that John Rawls’s model called reflective equilibrium might be workable.

scholarly journals Modifikasi Algoritma Genetika untuk Penyelesaian Permasalahan Penjadwalan Pelajaran Sekolah

2014 ◽  
Vol 10 (1) ◽  
pp. 111
Author(s):  
Rahman Erama ◽  
Retantyo Wardoyo
Keyword(s):  
Genetic Algorithm ◽  
Genetic Algorithms ◽  
Effective Algorithm ◽  
Scheduling Problems ◽  
The Core ◽  
Alternative Algorithm ◽  
Crossover Phase ◽  
School Scheduling ◽  
Core Problem ◽  
Standard Genetic Algorithm

AbstrakModifikasi Algoritma Genetika pada penelitian ini dilakukan berdasarkan temuan-temuan para peneliti sebelumnya tentang kelemahan Algoritma Genetika. Temuan-temuan yang dimakasud terkait proses crossover sebagai salah satu tahapan terpenting dalam Algoritma Genetika dinilai tidak menjamin solusi yang lebih baik oleh beberapa peneliti. Berdasarkan temuan-temuan oleh beberapa peneliti sebelumnya, maka penelitian ini akan mencoba memodifikasi Algoritma Genetika dengan mengeliminasi proses crossover yang menjadi inti permasalahan dari beberapa peneliti tersebut. Eliminasi proses crossover ini diharapkan melahirkan algoritma yang lebih efektif sebagai alternative untuk penyelesaian permasalahan khususnya penjadwalan pelajaran sekolah.Tujuan dari penelitian ini adalah Memodifikasi Algoritma Genetika menjadi algoritma alternatif untuk menyelesaikan permasalahan penjadwalan sekolah, sehingga diharapkan terciptanya algoritma alternatif ini bisa menjadi tambahan referensi bagi para peneliti untuk menyelesaikan permasalahan penjadwalan lainnya.Algoritma hasil modifikasi yang mengeliminasi tahapan crossover pada algoritma genetika ini mampu memberikan performa 3,06% lebih baik dibandingkan algoritma genetika sederhana dalam menyelesaikan permasalahan penjadwalan sekolah. Kata kunci—algoritma genetika, penjadwalan sekolah, eliminasi crossover  AbstractModified Genetic Algorithm in this study was based on the findings of previous researchers about the weakness of Genetic Algorithms. crossover as one of the most important stages in the Genetic Algorithms considered not guarantee a better solution by several researchers. Based on the findings by previous researchers, this research will try to modify the genetic algorithm by eliminating crossover2 which is the core problem of several researchers. Elimination crossover is expected to create a more effective algorithm as an alternative to the settlement issue in particular scheduling school.This study is intended to modify the genetic algorithm into an algorithm that is more effective as an alternative to solve the problems of school scheduling. So expect the creation of this alternative algorithm could be an additional resource for researchers to solve other scheduling problems.Modified algorithm that eliminates the crossover phase of the genetic algorithm is able to provide 2,30% better performance than standard genetic algorithm in solving scheduling problems school. Keywords—Genetic Algorithm, timetabling school, eliminate crossover

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