• 제목/요약/키워드: Random sets

검색결과 278건 처리시간 0.032초

Cloud Task Scheduling Based on Proximal Policy Optimization Algorithm for Lowering Energy Consumption of Data Center

  • Yang, Yongquan;He, Cuihua;Yin, Bo;Wei, Zhiqiang;Hong, Bowei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권6호
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    • pp.1877-1891
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    • 2022
  • As a part of cloud computing technology, algorithms for cloud task scheduling place an important influence on the area of cloud computing in data centers. In our earlier work, we proposed DeepEnergyJS, which was designed based on the original version of the policy gradient and reinforcement learning algorithm. We verified its effectiveness through simulation experiments. In this study, we used the Proximal Policy Optimization (PPO) algorithm to update DeepEnergyJS to DeepEnergyJSV2.0. First, we verify the convergence of the PPO algorithm on the dataset of Alibaba Cluster Data V2018. Then we contrast it with reinforcement learning algorithm in terms of convergence rate, converged value, and stability. The results indicate that PPO performed better in training and test data sets compared with reinforcement learning algorithm, as well as other general heuristic algorithms, such as First Fit, Random, and Tetris. DeepEnergyJSV2.0 achieves better energy efficiency than DeepEnergyJS by about 7.814%.

Research on Improving Memory of VR Game based on Visual Thinking

  • Lu, Kai;Cho, Dong Min;Zou, Jia Xing
    • 한국멀티미디어학회논문지
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    • 제25권5호
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    • pp.730-738
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    • 2022
  • Based on visual Thinking theory, VR(virtual reality) game changes the traditional form of memory and maps the content into game elements to realize the immersive spatial memory mode. This paper analyzes the influencing factors of game design and system function construction. This paper proposes a hypothesis: with the help of visual thinking theory, VR game is helpful to improve learners' visual memory, and carries out research. The experiment sets different levels of game through empirical research and case analysis of memory flip game. For example, when judging two random cards. If the pictures are the same, it will be judged as the correct combination; if they are different, the two cards will be restored to the original state. The results are analyzed by descriptive statistical analysis and AMOS data analysis. The results show that game content using the concept of "Memory Palace", which can improve the accuracy of memory. We conclude that the use of spatial localization characteristics in flip games combining visual thinking can improve users' memory by helping users memorize and organize information in a Virtual environment, which means VR games have strong feasibility and effectiveness in improving memory.

Markov Chain Monte Carlo simulation based Bayesian updating of model parameters and their uncertainties

  • Sengupta, Partha;Chakraborty, Subrata
    • Structural Engineering and Mechanics
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    • 제81권1호
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    • pp.103-115
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    • 2022
  • The prediction error variances for frequencies are usually considered as unknown in the Bayesian system identification process. However, the error variances for mode shapes are taken as known to reduce the dimension of an identification problem. The present study attempts to explore the effectiveness of Bayesian approach of model parameters updating using Markov Chain Monte Carlo (MCMC) technique considering the prediction error variances for both the frequencies and mode shapes. To remove the ergodicity of Markov Chain, the posterior distribution is obtained by Gaussian Random walk over the proposal distribution. The prior distributions of prediction error variances of modal evidences are implemented through inverse gamma distribution to assess the effectiveness of estimation of posterior values of model parameters. The issue of incomplete data that makes the problem ill-conditioned and the associated singularity problem is prudently dealt in by adopting a regularization technique. The proposed approach is demonstrated numerically by considering an eight-storey frame model with both complete and incomplete modal data sets. Further, to study the effectiveness of the proposed approach, a comparative study with regard to accuracy and computational efficacy of the proposed approach is made with the Sequential Monte Carlo approach of model parameter updating.

Organizational Justice, Job Satisfaction and Islamic Spirituality among Malaysian SME Employees

  • MANAF, Abdul Halim Bin Abdul;SULAIMAN, Mohamed;SARIF, Suhaimi Mhd;OTHMAN, Abdul Kadir
    • The Journal of Asian Finance, Economics and Business
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    • 제9권1호
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    • pp.259-271
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    • 2022
  • The role of Islamic spirituality in the relationship between organizational justice (OJ) and job satisfaction is investigated in this study (JS). The three components of OJ in this study are distributive, procedural, and interactional justice. Islamic spirituality (IS) is founded on piety values, and IS was used as a moderating factor in this study to alter the link between OJ and JS among Malaysian employees of small and medium enterprises (SMEs). Four hundred sets of the questionnaire were issued using a simple random selection procedure, yielding 276 completed responses, suggesting a 69 percent response rate. Multiple Linear Regression Analysis (MLRA) was used to test the proposed relationships. The findings of the study demonstrate that the three OJ aspects have a considerable impact on employee JS, indicating the significance of these elements in ensuring that employees are satisfied with their jobs. IS, on the other hand, had no effect on the link between the OJ dimensions and JS. This research has added to the existing body of knowledge by giving further empirical evidence on the impact of OJ aspects on employee JS in SMEs, notably in Malaysia.

Identification of Contaminant Injection in Water Distribution Network

  • Marlim, Malvin Samuel;Kang, Doosun
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2020년도 학술발표회
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    • pp.114-114
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    • 2020
  • Water contamination in a water distribution network (WDN) is harmful since it directly induces the consumer's health problem and suspends water service in a wide area. Actions need to be taken rapidly to countermeasure a contamination event. A contaminant source ident ification (CSI) is an important initial step to mitigate the harmful event. Here, a CSI approach focused on determining the contaminant intrusion possible location and time (PLoT) is introduced. One of the methods to discover the PLoT is an inverse calculation to connect all the paths leading to the report specification of a sensor. A filtering procedure is then applied to narrow down the PLoT using the results from individual sensors. First, we spatially reduce the suspect intrusion points by locating the highly suspicious nodes that have similar intrusion time. Then, we narrow the possible intrusion time by matching the suspicious intrusion time to the reported information. Finally, a likelihood-score is estimated for each suspect. Another important aspect that needs to be considered in CSI is that there are inherent uncertainties, such as the variations in user demand and inaccuracy of sensor data. The uncertainties can lead to overlooking the real intrusion point and time. To reflect the uncertainties in the CSI process, the Monte-Carlo Simulation (MCS) is conducted to explore the ranges of PLoT. By analyzing all the accumulated scores through the random sets, a spread of contaminant intrusion PLoT can then be identified in the network.

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Using Machine Learning Techniques for Accurate Attack Detection in Intrusion Detection Systems using Cyber Threat Intelligence Feeds

  • Ehtsham Irshad;Abdul Basit Siddiqui
    • International Journal of Computer Science & Network Security
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    • 제24권4호
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    • pp.179-191
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    • 2024
  • With the advancement of modern technology, cyber-attacks are always rising. Specialized defense systems are needed to protect organizations against these threats. Malicious behavior in the network is discovered using security tools like intrusion detection systems (IDS), firewall, antimalware systems, security information and event management (SIEM). It aids in defending businesses from attacks. Delivering advance threat feeds for precise attack detection in intrusion detection systems is the role of cyber-threat intelligence (CTI) in the study is being presented. In this proposed work CTI feeds are utilized in the detection of assaults accurately in intrusion detection system. The ultimate objective is to identify the attacker behind the attack. Several data sets had been analyzed for attack detection. With the proposed study the ability to identify network attacks has improved by using machine learning algorithms. The proposed model provides 98% accuracy, 97% precision, and 96% recall respectively.

RAMP를 이용한 황정과 위유의 유전적 분석 (Genetic Analysis of Polygonati Rhizoma and Polygonati odorati Rhizoma using Random Amplified Microsatellite Polymorphism)

  • 안선민;육진아;김영화;채병찬;김홍준;김기훈;강권규;고병섭;이미영
    • 한국약용작물학회지
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    • 제14권3호
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    • pp.125-129
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    • 2006
  • 형태학적으로 구분이 어려운 황정과 위유의 범위를 구분하기 위해 황정에 속하는 층층갈고리둥굴레, 다화황정, 진황정 등 3종과 위유에 속하는 8종의 둥굴레 동속 식물 등 11종 23 개체 시료로 RAMP분석한 결과를 요약하면 다음과 같다. 1. 황정그룹과 위유그룹은 NTSYS를 통한 유연관계 분석에서 55%의 유연관계를 나타냈으며, 층층갈고리둥굴레와 층층둥굴레는 81.75%로 분석에 사용된 둥글레 동속 식물 중 가장 높은 유연관계를 나타냈다. 2. 둥굴레 동속식물에 해당하는 층층둥글레는 황정의 약재인 층층갈고리둥굴레와 외부형태학적으로, 그리고 다형성패턴결과가 매우 유사하므로 황정의 약재에 속하는 것으로 사료된다. 3. 진황정은 위유와 외부형태적으로 유사하며, 유연관계분석에서도 위유의 그룹에 속하므로 위유의 약재에 대한 구분을 새롭게 할 필요성이 있다.

이분형 자료의 분류문제에서 불균형을 다루기 위한 표본재추출 방법 비교 (Comparison of resampling methods for dealing with imbalanced data in binary classification problem)

  • 박근우;정인경
    • 응용통계연구
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    • 제32권3호
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    • pp.349-374
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    • 2019
  • 이분형 자료의 분류에서 자료의 불균형 정도가 심한 경우 분류 결과가 좋지 않을 수 있다. 이런 문제 해결을 위해 학습 자료를 변형시키는 등의 연구가 활발히 진행되고 있다. 본 연구에서는 이러한 이분형 자료의 분류문제에서 불균형을 다루기 위한 방법들 중 표본재추출 방법들을 비교하였다. 이를 통해 자료에서 희소계급의 탐지를 보다 효과적으로 하는 방법을 찾고자 하였다. 모의실험을 통하여 여러 오버샘플링, 언더샘플링, 오버샘플링과 언더샘플링 혼합방법의 총 20가지를 비교하였다. 분류문제에서 대표적으로 쓰이는 로지스틱 회귀분석, support vector machine, 랜덤포레스트 모형을 분류기로 사용하였다. 모의실험 결과, 정확도가 0.5 이상이면서 민감도가 높았던 표본재추출 방법은 random under sampling (RUS)였다. 그 다음으로 민감도가 높았던 방법은 오버샘플링 ADASYN (adaptive synthetic sampling approach)이었다. 이를 통해 RUS 방법이 희소계급값을 찾기 위한 방안으로는 적합했다는 것을 알 수 있었다. 몇 가지 실제 자료에 적용한 결과도 모의실험의 결과와 비슷한 양상을 보였다.

다중모형조합기법을 이용한 상품추천시스템 (Product Recommender Systems using Multi-Model Ensemble Techniques)

  • 이연정;김경재
    • 지능정보연구
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    • 제19권2호
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    • pp.39-54
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    • 2013
  • 전자상거래의 폭발적 증가는 소비자에게 더 유리한 많은 구매 선택의 기회를 제공한다. 이러한 상황에서 자신의 구매의사결정에 대한 확신이 부족한 소비자들은 의사결정 절차를 간소화하고 효과적인 의사결정을 위해 추천을 받아들인다. 온라인 상점의 상품추천시스템은 일대일 마케팅의 대표적 실현수단으로써의 가치를 인정받고 있다. 그러나 사용자의 기호를 제대로 반영하지 못하는 추천시스템은 사용자의 실망과 시간낭비를 발생시킨다. 본 연구에서는 정확한 사용자의 기호 반영을 통한 추천기법의 정교화를 위해 데이터마이닝과 다중모형조합기법을 이용한 상품추천시스템 모형을 제안하고자 한다. 본 연구에서 제안하는 모형은 크게 두 개의 단계로 이루어져 있으며, 첫 번째 단계에서는 상품군 별 우량고객 선정 규칙을 도출하기 위해서 로지스틱 회귀분석 모형, 의사결정나무 모형, 인공신경망 모형을 구축한 후 다중모형조합기법인 Bagging과 Bumping의 개념을 이용하여 세 가지 모형의 결과를 조합한다. 두 번째 단계에서는 상품군 별 연관관계에 관한 규칙을 추출하기 위하여 장바구니분석을 활용한다. 상기의 두 단계를 통하여 상품군 별로 구매가능성이 높은 우량고객을 선정하여 그 고객에게 관심을 가질만한 같은 상품군 또는 다른 상품군 내의 다른 상품을 추천하게 된다. 제안하는 상품추천시스템은 실제 운영 중인 온라인 상점인 'I아트샵'의 데이터를 이용하여 프로토타입을 구축하였고 실제 소비자에 대한 적용가능성을 확인하였다. 제안하는 모형의 유용성을 검증하기 위하여 제안 상품추천시스템의 추천과 임의 추천을 통한 추천의 결과를 사용자에게 제시하고 제안된 추천에 대한 만족도를 조사한 후 대응표본 T검정을 수행하였으며, 그 결과 사용자의 만족도를 유의하게 향상시키는 것으로 나타났다.

STANDARDISATION OF NIR INSTRUMENTS, INFLUENCE OF THE CALIBRATION METHODS AND THE SIZE OF THE CLONING SET

  • Dardenne, Pierre;Cowe, Ian-A.;Berzaghi, Paolo;Flinn, Peter-C.;Lagerholm, Martin;Shenk, John-S.;Westerhaus, Mark-O.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1121-1121
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    • 2001
  • A previous study (Berzaghi et al., 2001) evaluated the performance of 3 calibration methods, modified partial least squares (MPLS), local PLS (LOCAL) and artificial neural networks (ANN) on the prediction of the chemical composition of forages, using a large NIR database. The study used forage samples (n=25,977) from Australia, Europe (Belgium, Germany, Italy and Sweden) and North America (Canada and U.S.A) with reference values for moisture, crude protein and neutral detergent fibre content. The spectra of the samples were collected using 10 different Foss NIR Systems instruments, only some of which had been standardized to one master instrument. The aim of the present study was to evaluate the behaviour of these different calibration methods when predicting the same samples measured on different instruments. Twenty-two sealed samples of different kind of forages were measured in duplicate on seven instruments (one master and six slaves). Three sets of near infrared spectra (1100 to 2500nm) were created. The first set consisted of the spectra in their original form (unstandardized); the second set was created using a single sample standardization (Clone1); the third was created using a multiple sample procedure (Clone6). WinISI software (Infrasoft International Inc., Port Mathilda, PA, USA) was used to perform both types of standardization, Clone1 is just a photometric offset between a “master” instrument and the “slave” instrument. Clone6 modifies both the X-axis through a wavelength adjustment and the Y-axis through a simple regression wavelength by wavelength. The Clone1 procedure used one sample spectrally close to the centre of the population. The six samples used in Clone 6 were selected to cover the range of spectral variation in the sample set. The remaining fifteen samples were used to evaluate the performances of the different models. The predicted values for dry matter, protein and neutral detergent fibre from the master Instrument were considered as “reference Y values” when computing the statistics RMSEP, SEPC, R, Bias, Slope, mean GH (global Mahalanobis distance) and mean NH (neighbourhood Mahalanobis distance) for the 6 slave instruments. From the results we conclude that i) all the calibration techniques gave satisfactory results after standardization. Without standardization the predicted data from the slaves would have required slope and bias correction to produce acceptable statistics. ii) Standardization reduced the errors for all calibration methods and parameters tested, reducing not only systematic biases but also random errors. iii) Standardization removed slope effects that were significantly different from 1.0 in most of the cases. iv) Clone1 and Clone6 gave similar results except for NDF where Clone6 gave better RMSEP values than Clone1. v) GH and NH were reduced by half even with very large data sets including unstandardized spectra.

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