222 results on '"Van-Nam Huynh"'
Search Results
2. A Hybrid Use of Soft Systems Methodology for Developing a Framework of Evidence-Based Teaching for Hospitality and Tourism Instructors in Vietnam
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Thanh-Thao Luong, Van-Nam Huynh, and Eunyoung Kim
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Management of Technology and Innovation ,Strategy and Management - Abstract
This paper adopts the hybrid use of
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- 2022
3. 3-Tuple Linguistic Distance-Based Model for a New Product go/no-go Evaluation
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Sirin Suprasongsin, Pisal Yenradee, Van-Nam Huynh, and Suchada Rianmora
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Artificial Intelligence ,Control and Systems Engineering ,Software ,Information Systems - Abstract
There is a need for a probabilistic linguistic term set model for go/no-go product screening problem for new product development to meet a firm’s expectation. This paper develops a novel 3-tuple linguistic distance-based model to evaluate whether an overall respondents perception meets a firm’s expectation (“go”) for new product development. The respondent’s perception is collected by a Kansei-based survey as an interval-linguistic term. Then, an expected distance between the firm’s expectation and the respondent’s perception is computed by a target-based Manhattan distance measure. The expected distance is compared with a threshold to shows that what product attribute meets the firm’s expectation based on customers’ perceptions. A real case study of Thai-tea soy milk packaging design is provided. The proposed model is compared to the existing model to show its effectiveness and applicability. Experimental results show that the proposed model can effectively point out the inferior product attributes, which leads to redesign the product until all product concepts meet the target attributes before launching the product to the market. Thus, it can significantly reduce the risk of failure of the product in a real market. This paper has significant contributions in that it allows respondents to provide their opinions with uncertainty by providing an interval linguistic assessment, handles a bias of the heterogeneity of respondents by determining the weight of respondents, and overcomes limitations of existing models by applying target-oriented linguistic terms.
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- 2022
4. Deep Generative Networks Coupled With Evidential Reasoning for Dynamic User Preferences Using Short Texts
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Duc-Vinh Vo, Trung-Tin Tran, Kiyoaki Shirai, and Van-Nam Huynh
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Computational Theory and Mathematics ,Computer Science Applications ,Information Systems - Published
- 2022
5. A Novel Cluster Prediction Approach Based on Locality-Sensitive Hashing for Fuzzy Clustering of Categorical Data
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Toan Nguyen Mau, Yasushi Inoguchi, and Van-Nam Huynh
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General Computer Science ,General Engineering ,General Materials Science ,Electrical and Electronic Engineering - Published
- 2022
6. A Demand-Driven Model for Reallocating Workers in Assembly Lines
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Randall Mauricio Perez-Wheelock, Wei Ou, Pisal Yenradee, and Van-Nam Huynh
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General Computer Science ,General Engineering ,General Materials Science ,Electrical and Electronic Engineering - Published
- 2022
7. A Multi-Criteria Collaborative Filtering Approach Using Deep Learning and Dempster-Shafer Theory for Hotel Recommendations
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Van-Nam HUYNH, Quang-Hung Le, Toan Nguyen Mau, and Roengchai Tansuchat
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General Computer Science ,General Engineering ,General Materials Science - Published
- 2022
8. Learning Perceptual Position-Aware Shapelets for Time Series Classification
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Xuan-May Le, Minh-Tuan Tran, and Van-Nam Huynh
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- 2023
9. Linguistic Relational Database Systems with a Unified Formalism Representing Different Data Types by Their Neighborhoods
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Cat Ho Nguyen, Van-Nam Huynh, Nhat Minh Nguyen, Phong Dinh Pham, Thong Van Hoang, Ban Van Doan, Bao Nguyen Le, and Như Gia Nguyễn
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- 2023
10. An LSH-based k-representatives clustering method for large categorical data
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Toan Nguyen Mau and Van-Nam Huynh
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Boosting (machine learning) ,Computational complexity theory ,business.industry ,Computer science ,Cognitive Neuroscience ,Nearest neighbor search ,Big data ,Hash function ,computer.software_genre ,Computer Science Applications ,ComputingMethodologies_PATTERNRECOGNITION ,Similarity (network science) ,Artificial Intelligence ,Data mining ,business ,Cluster analysis ,Categorical variable ,computer - Abstract
Clustering categorical data remains a challenging problem in the era of big data, due to the difficulty in measuring dis/similarity meaningfully for categorical data and the high computational complexity of existing clustering algorithms that makes it difficult to be applied in practical use for big data mining applications. In this paper, we propose an integrated approach that incorporates the Locality-Sensitive Hashing (LSH) technique into the k -means-like clustering so as to make it capable of predicting the better initial clusters for boosting clustering effectiveness. To this end, we first utilize a data-driven dissimilarity measure for categorical data to construct a family of binary hash functions that are then used to generate the initial clusters. We also propose to use a nearest neighbor search at each iteration for cluster reassignment of data objects to improve the clustering complexity. These solutions are incorporated into the k -representatives algorithm resulting in the so-called LSH- k -representatives algorithm. Extensive experiments conducted on multiple real-world and synthetic datasets have demonstrated the effectiveness of the proposed method. It is shown that the newly developed algorithm yields comparable or better clustering results in comparison to the existing closely related works, yet it is significantly more efficient by a factor of between 2 × and 32 × .
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- 2021
11. Clustering mixed numerical and categorical data with missing values
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Van-Nam Huynh, Duy-Tai Dinh, and Songsak Sriboonchitta
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Information Systems and Management ,Computer science ,Initialization ,02 engineering and technology ,Measure (mathematics) ,Theoretical Computer Science ,Set (abstract data type) ,Artificial Intelligence ,0202 electrical engineering, electronic engineering, information engineering ,Imputation (statistics) ,Cluster analysis ,Categorical variable ,business.industry ,05 social sciences ,050301 education ,Pattern recognition ,Missing data ,Computer Science Applications ,ComputingMethodologies_PATTERNRECOGNITION ,Control and Systems Engineering ,Scalability ,020201 artificial intelligence & image processing ,Artificial intelligence ,business ,0503 education ,Software - Abstract
This paper proposes a novel framework for clustering mixed numerical and categorical data with missing values. It integrates the imputation and clustering steps into a single process, which results in an algorithm named C lustering M ixed Numerical and Categorical Data with M issing Values (k-CMM). The algorithm consists of three phases. The initialization phase splits the input dataset into two parts based on missing values in objects and attributes types. The imputation phase uses the decision-tree-based method to find the set of correlated data objects. The clustering phase uses the mean and kernel-based methods to form cluster centers at numerical and categorical attributes, respectively. The algorithm also uses the squared Euclidean and information-theoretic-based dissimilarity measure to compute the distances between objects and cluster centers. An extensive experimental evaluation was conducted on real-life datasets to compare the clustering quality of k-CMM with state-of-the-art clustering algorithms. The execution time, memory usage, and scalability of k-CMM for various numbers of clusters or data sizes were also evaluated. Experimental results show that k-CMM can efficiently cluster missing mixed datasets as well as outperform other algorithms when the number of missing values increases in the datasets.
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- 2021
12. The Impact of Knowledge Management Activities on Employee Performance in Vietnamese Banks
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Nu Dieu Khue Ngo, Jader Zelaya, and Van Nam Huynh
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- 2022
13. Towards a Human-like Chatbot using Deep Adversarial Learning
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Quoc-Dai Luong Tran, Anh-Cuong Le, and Van-Nam Huynh
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- 2022
14. An evaluation model for task complexity in production lines
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Song Thanh Quynh Le and Van Nam Huynh
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Strategy and Management ,General Business, Management and Accounting - Abstract
PurposeTask complexity is one of the significant factors that influences and is used for forecasting employee performance and determining labor cost. However, the complexity level of tasks is unstructured, dynamic and complicated to perform. This paper develops a new method for evaluating the complexity level of tasks in the production process to support production managers to control their manufacturing systems in terms of flexibility, reliability to production planning and labor cost.Design/methodology/approachThe complexity level of tasks will be analyzed based on the structuralist concept. Using the structure of task, the factors that significantly affect the task complexity in an assembly line will be defined, and the complexity level of the task will be evaluated by measuring the number of task components. Using the proportional 2-tuples linguistic values, the difference between the complexity levels of tasks can be compared and described clearly.FindingsBased on the structure of the task, three contributory factors including input factors, process-operation factors and output factors that significantly affect the task complexity in an assembly line are identified in the present study. The complexity level of the task is quantified through analyzing the details of the three factors according to two criteria and six sub-criteria within the textile case study.Originality/valueThe proposed approach provides a new insight about the factors that have an effect on the complexity of tasks in production and remedies some of limitations of previous methods. The combination of experts' experience and scientific knowledge will improve the accuracy in determining the complexity level of tasks.
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- 2022
15. Integrated preference argumentation and applications in consumer behaviour analyses
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Hung Nguyen Duy and Van-Nam Huynh
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Artificial Intelligence ,Applied Mathematics ,Software ,Theoretical Computer Science - Published
- 2023
16. An integrated framework of learning and evidential reasoning for user profiling using short texts
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Van-Nam Huynh, Jessada Karnjana, and Duc-Vinh Vo
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Information retrieval ,User profile ,Word embedding ,Computer science ,User modeling ,Evidential reasoning approach ,020206 networking & telecommunications ,02 engineering and technology ,Recommender system ,Hardware and Architecture ,Signal Processing ,0202 electrical engineering, electronic engineering, information engineering ,Profiling (information science) ,020201 artificial intelligence & image processing ,Cluster analysis ,Pignistic probability ,Software ,Information Systems - Abstract
Inferring user profiles based on texts created by users on social networks has a variety of applications in recommender systems such as job offering, item recommendation, and targeted advertisement. The problem becomes more challenging when working with short texts like tweets on Twitter, or posts on Facebook. This work aims at proposing an integrated framework based on Dempster–Shafer theory of evidence, word embedding, and k -means clustering for user profiling problem, which is capable of not only working well with short texts but also dealing with uncertainty inherently in user texts. The proposed framework is essentially composed of three phases: (1) Learning abstract concepts at multiple levels of abstraction from user corpora; (2) Evidential inference and combination for user modeling; and (3) User profile extraction. Particularly, in the first phase, a word embedding technique is used to convert preprocessed texts into vectors which capture semantics of words in user corpus, and then k -means clustering is utilized for learning abstract concepts at multiple levels of abstraction, each of which reflects appropriate semantics of user profiles. In the second phase, by considering each document in user corpus as an evidential source that carries some partial information for inferring user profiles, we first infer a mass function associated with each user document by maximum a posterior estimation, and then apply Dempster’s rule of combination for fusing all documents’ mass functions into an overall one for the user corpus. Finally, in the third phase, we apply the so-called pignistic probability principle to extract top- n keywords from user’s overall mass function to define the user profile. Thanks to the ability of combining pieces of information from many documents, the proposed framework is flexible enough to be scaled when input data coming from not only multiple modes but different sources on web environments. Besides, the resulting profiles are interpretable, visualizable, and compatible in practical applications. The effectiveness of the proposed framework is validated by experimental studies conducted on datasets crawled from Twitter and Facebook.
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- 2021
17. A multi-objective optimization model for shelter location-allocation in response to humanitarian relief logistics
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Panchalee Praneetpholkrang, Sarunya Kanjanawattana, and Van-Nam Huynh
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Service (systems architecture) ,Operations research ,Computer science ,Total cost ,Transportation ,HF5761-5780 ,Management Science and Operations Research ,Multi-objective optimization ,Management of Technology and Innovation ,Goal programming ,0502 economics and business ,Business and International Management ,Fixed cost ,Constraint (mathematics) ,050210 logistics & transportation ,Multi-criteria ,Shipment of goods. Delivery of goods ,05 social sciences ,Pareto efficiency ,Disaster management ,Discrete facility location ,Goal Programming ,Emergency logistics ,Location-allocation ,Epsilon Constraint method ,050203 business & management - Abstract
Decision-making for shelter location-allocation influences the success of disaster response and affects the security of victims. This paper proposes a multi-objective optimization model for determining shelter location-allocation in response to humanitarian relief logistics. Three objective functions are formulated to improve both efficiency and effectiveness. The first objective is to minimize total costs, including fixed costs for opening the shelters, transportation costs, and service costs. The second objective is to minimize the total time for evacuating victims from all affected areas to allocated shelters. The third objective is to minimize the number of shelters required to provide thorough service to victims. The Epsilon Constraint method (EC) and Goal Programming (GP) are employed for solving the proposed model. The applicability of the proposed model is validated through a case study of flooding in Surat Thani, Thailand. The Pareto efficiency obtained from solving the proposed model is compared with current shelter location-allocation plans determined by the government sector. The comparisons reveal that the results obtained from solving the proposed model outperform current shelter location-allocation plans. Furthermore, the results of this study could provide an advantage to decision-makers considering appropriate strategies for disaster response.
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- 2021
18. Role of project management on Sustainable Supply Chain development through Industry 4.0 technologies and Circular Economy during the COVID-19 pandemic: A multiple case study of Thai metals industry
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Vichathorn Piyathanavong, Van-Nam Huynh, Jessada Karnjana, and Sun Olapiriyakul
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Management of Technology and Innovation ,Strategy and Management ,Management Science and Operations Research ,Industrial and Manufacturing Engineering - Published
- 2022
19. Revealed preference in argumentation: Algorithms and applications
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Van-Nam Huynh and Nguyen Duy Hung
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Computer science ,Preference revelation ,Applied Mathematics ,02 engineering and technology ,Unobservable ,Preference ,Theoretical Computer Science ,Argumentation theory ,Artificial Intelligence ,Argument ,020204 information systems ,Revealed preference ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Set (psychology) ,Preference relation ,Algorithm ,Software - Abstract
Argumentative agents in AI are inspired by how humans reason by exchange of arguments. Given the same set of arguments possibly attacking one another (Dung's AA framework) these agents are bound to accept the same subset of those arguments (aka extension) unless they reason by different argumentation semantics. However humans may not be so predictable, and in this paper we assume that this is because any real agent's reasoning is inevitably influenced by her own preferences over the arguments. Though such preferences are usually unobservable, their effects on the agent's reasoning cannot be washed out. Hence by reconstructing her reasoning process, we might uncover her hidden preferences, which then allow us to predict what else the agent must accept. Concretely we formalize and develop algorithms for such problems as uncovering the hidden argument preference relation of an agent from her expressed opinion, by which we mean a subset of arguments or attacks she accepted from a given AA framework; and uncovering the collective preferences of a group from a dataset of individual opinions. A major challenge we addressed in this endeavor is to deal with “answer sets” of argument preference relations which are generally exponential or even infinite. So we start by developing a compact representation for such answer sets called preference states. Preference revelation tasks are then structured as derivations of preference states from data, and reasoning prediction tasks are reduced to manipulations of derived preference states without enumerating the underlying (possibly infinite) answer sets. We also apply the presented results to two non-trivial problems: learning preferences over rules in structured argumentation with priorities – an open problem so far; and analyzing public polls in apparently deeper ways than existing social argumentation frameworks allow.
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- 2021
20. Preface: recent advances in knowledge modelling and decision making with uncertainties
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Van-Nam Huynh and Hong-Bin Yan
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Computer science ,Management science ,Theory of computation ,General Decision Sciences ,Management Science and Operations Research ,Knowledge modelling - Published
- 2021
21. Catalytic upgrading and enhancing the combustion characteristic of pyrolysis oil
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Tho Dinh Son Van, Van Nam Huynh, Nguyen Thoai Dang, and Thanh Tam Truong
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Renewable Energy, Sustainability and the Environment ,020209 energy ,Evaporation ,02 engineering and technology ,Combustion ,Catalysis ,chemistry.chemical_compound ,020401 chemical engineering ,chemistry ,Chemical engineering ,Pyrolysis oil ,Furan ,0202 electrical engineering, electronic engineering, information engineering ,Phenol ,Heat of combustion ,0204 chemical engineering ,Bagasse - Abstract
Bagasse’s pyrolysis oil has low calorific value, high water content, and acidity. The main components of the pyrolysis oil are acids/esters, alcohols, aldehydes/ketones, furan compounds, phenol com...
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- 2021
22. A Hybrid Reinforcement Learning-Based Model for the Vehicle Routing Problem in Transportation Logistics
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Teerayut Horanont, Thananut Phiboonbanakit, Van-Nam Huynh, and Thepchai Supnithi
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reinforcement learning ,General Computer Science ,Operations research ,Computer science ,logistics ,General Engineering ,TK1-9971 ,Freight ,Vehicle routing problem ,Transportation logistics ,Reinforcement learning ,vehicle routing problem ,General Materials Science ,Electrical engineering. Electronics. Nuclear engineering ,intelligent transportation ,policy - Abstract
Currently, the number of deliveries handled by transportation logistics is rapidly increasing because of the significant growth of the e-commerce industry, resulting in the need for improved functional vehicle routing measures for logistic companies. The effective management of vehicle routing helps companies reduce operational costs and increases its competitiveness. The vehicle routing problem (VRP) seeks to identify optimal routes for a fleet of vehicles to deliver goods to customers while simultaneously considering changing requirements and uncertainties in the transportation environment. Due to its combinatorial nature and complexity, conventional optimization approaches may not be practical to solve VRP. In this paper, a new optimization model based on reinforcement learning (RL) and a complementary tree-based regression method is proposed. In our proposed model, when the RL agent performs vehicle routing optimization, its state and action are fed into the tree-based regression model to assess whether the current route is feasible according to the given environment, and the response received is used by the RL agent to adjust actions for optimizing the vehicle routing task. The procedure repeats iteratively until the maximum iteration is reached, then the optimal vehicle route is returned and can be utilized to assist in decision making. Multiple logistics agency case studies are conducted to demonstrate the application and practicality of the proposed model. The experimental results indicate that the proposed technique significantly improves profit gains up to 37.63% for logistics agencies compared with the conventional approaches.
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- 2021
23. An efficient approach for privacy preserving decentralized deep learning models based on secure multi-party computation
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Van-Nam Huynh, Anh-Tu Tran, Jessada Karnjana, and The-Dung Luong
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0209 industrial biotechnology ,business.industry ,Computer science ,Cognitive Neuroscience ,Distributed computing ,Deep learning ,Cryptography ,02 engineering and technology ,Computer Science Applications ,020901 industrial engineering & automation ,Artificial Intelligence ,0202 electrical engineering, electronic engineering, information engineering ,Secure multi-party computation ,Differential privacy ,020201 artificial intelligence & image processing ,Artificial intelligence ,business ,Protocol (object-oriented programming) - Abstract
This paper aims to develop a new efficient framework named Secure Decentralized Training Framework (SDTF) for Privacy Preserving Deep Learning models. The main feature of the proposed framework is its capable of working on a decentralized network setting that does not need a trusted third-party server while simultaneously ensuring the privacy of local data with a low cost of communication bandwidth. Particularly, we first propose a so-called Efficient Secure Sum Protocol (ESSP) that enables a large group of parties to jointly calculate a sum of private inputs. ESSP can work not only with integer number but also with floating point number without any data conversion. We then propose a Secure Model Sharing Protocol that enables a group of parties securely train and share the local models to be aggregated into a global model. Secure Model Sharing Protocol exploits randomization techniques and ESSP to protect local models from any honest-but-curious party even n - 2 of n parties colluding. Eventually, these protocols are employed for collaborative training decentralized deep learning models. We conduct theoretical evaluation of privacy and communication cost as well as empirical experiments on balance class image datasets (MNIST) and an unbalance class text dataset (UCI SMS Spam). These experiments demonstrate the proposed approach can obtain high accuracy (i.e. 97% baseline accuracy in only 10 training rounds with MNIST, 100 training rounds with SMS Spam) and robust to the heterogeneity decentralized network, with non-IID and unbalance data distributions. We also show a reduction in required rounds of training to achieve the accuracy baseline by 5 × as compared to Downpour SGD. It is shown that the proposed approach can achieve both the privacy at the level of cryptographic approaches and efficiency at the level of randomization techniques, while it also retains higher model’s utility than differential privacy approaches.
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- 2021
24. A Mass-Based Approach for Local Outlier Detection
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Anh Hoang, Van-Nam Huynh, Duc-Vinh Vo, and Toan Nguyen Mau
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General Computer Science ,Computer science ,knowledge discovery ,mass-based dissimilarity ,Context (language use) ,02 engineering and technology ,unsupervised learning ,computer.software_genre ,Measure (mathematics) ,Data modeling ,Set (abstract data type) ,Outlier detection ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,Point (geometry) ,Context model ,020208 electrical & electronic engineering ,General Engineering ,ComputingMethodologies_PATTERNRECOGNITION ,Outlier ,020201 artificial intelligence & image processing ,Anomaly detection ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Data mining ,lcsh:TK1-9971 ,computer - Abstract
This paper proposes a new outlier detection approach that measures the degree of outlierness for each instance in a given dataset. The proposed model utilizes a mass-based dissimilarity measure to address the weaknesses of neighbor-based outlier models while detecting local outliers in the dataset within a variety of data point densities. In particular, it first applies a hierarchical partitioning technique to generate a set of tree-like nested structure partitions for the input dataset, and then a mass-based dissimilarity measure is defined to quantify the dissimilarity between two data instances given the generated hierarchical partition structure. After that, for each data instance, a context set is obtained by gathering the neighbors around it with the $k$ lowest mass dissimilarities, and based on those context sets, a mass-based local outlier score model is introduced to compute the outlierness for each individual instance. The proposed approach fundamentally changes the perspective of the outlier model by using the mass-based measurement instead of the distance-based functions used in most neighbor-based methods. A comprehensive experiment conducted on both synthetic and real-world datasets demonstrates that the proposed approach is not only competitive with the existing state-of-the-art outlier detection models but is also an efficient and effective alternative for local outlier detection methods.
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- 2021
25. Integrating Community Context Information Into a Reliably Weighted Collaborative Filtering System Using Soft Ratings
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Van-Nam Huynh, Van-Doan Nguyen, and Songsak Sriboonchitta
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Social network ,Computer science ,business.industry ,02 engineering and technology ,Recommender system ,Machine learning ,computer.software_genre ,Computer Science Applications ,Human-Computer Interaction ,Community context ,Control and Systems Engineering ,Complete information ,020204 information systems ,Recommender systems ,0202 electrical engineering, electronic engineering, information engineering ,Collaborative filtering ,Dempster-Shafer theory (DST) ,020201 artificial intelligence & image processing ,Data mining ,Artificial intelligence ,Electrical and Electronic Engineering ,Uncertain reasoning ,business ,computer ,Software - Abstract
In this paper, we aim at developing a new collaborative filtering recommender system using soft ratings, which is capable of dealing with both imperfect information about user preferences and the sparsity problem. On the one hand, Dempster-Shafer theory is employed for handling the imperfect information due to its advantage in providing not only a flexible framework for modeling uncertain, imprecise, and incomplete information, but also powerful operations for fusion of information from multiple sources. On the other hand, in dealing with the sparsity problem, community context information that is extracted from the social network containing all users is used for predicting unprovided ratings. As predicted ratings are not a hundred percent accurate, while the provided ratings are actually evaluated by users, we also develop a new method for calculating user-user similarities, in which provided ratings are considered to be more significant than predicted ones. In the experiments, the developed recommender system is tested on two different data sets; and the experiment results indicate that this system is more effective than CoFiDS, a typical recommender system offering soft ratings.
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- 2020
26. k-PbC: an improved cluster center initialization for categorical data clustering
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Duy-Tai Dinh and Van-Nam Huynh
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Measure (data warehouse) ,Computer science ,Initialization ,02 engineering and technology ,computer.software_genre ,Data set ,Set (abstract data type) ,ComputingMethodologies_PATTERNRECOGNITION ,Artificial Intelligence ,Kernel (statistics) ,0202 electrical engineering, electronic engineering, information engineering ,Cluster (physics) ,020201 artificial intelligence & image processing ,Data mining ,Cluster analysis ,Categorical variable ,computer - Abstract
The performance of a partitional clustering algorithm is influenced by the initial random choice of cluster centers. Different runs of the clustering algorithm on the same data set often yield different results. This paper addresses that challenge by proposing an algorithm named k-PbC, which takes advantage of non-random initialization from the view of pattern mining to improve clustering quality. Specifically, k-PbC first performs a maximal frequent itemset mining approach to find a set of initial clusters. It then uses a kernel-based method to form cluster centers and an information-theoretic based dissimilarity measure to estimate the distance between cluster centers and data objects. An extensive experimental study was performed on various real categorical data sets to draw a comparison between k-PbC and state-of-the-art categorical clustering algorithms in terms of clustering quality. Comparative results have revealed that the proposed initialization method can enhance clustering results and k-PbC outperforms compared algorithms for both internal and external validation metrics.
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- 2020
27. Mining top-k frequent patterns from uncertain databases
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Ngoc Thanh Nguyen, Bay Vo, Sung Wook Baik, Tuong Le, and Van-Nam Huynh
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Database ,Artificial Intelligence ,Computer science ,Scalability ,Rank (computer programming) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,02 engineering and technology ,computer.software_genre ,computer ,Task (project management) - Abstract
Mining uncertain frequent patterns (UFPs) from uncertain databases was recently introduced, and there are various approaches to solve this problem in the last decade. However, systems are often faced with the problem of too many UFPs being discovered by the traditional approaches to this issue, and thus will spend a lot of time and resources to rank and find the most promising patterns. Therefore, this paper introduces a task named mining top-k UFPs from uncertain databases. We then propose an efficient method named TUFP (mining Top-k UFPs) to carry this out. Effective threshold raising strategies are introduced to help the proposed algorithm reduce the number of generated candidates to enhance the performance in terms of the runtime as well as memory usage. Finally, several experiments on the number of generated candidates, mining time, memory usage and scalability of TUFP and two state-of-the-art approaches (CUFP-mine and LUNA) were conducted. The performance studies show that TUFP is efficient in terms of mining time, memory usage and scalability for mining top-k UFPs.
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- 2020
28. On Sampling Techniques for Corporate Credit Scoring
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Hung Ba Nguyen and Van-Nam Huynh
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021103 operations research ,Ensemble forecasting ,business.industry ,Computer science ,0211 other engineering and technologies ,02 engineering and technology ,Machine learning ,computer.software_genre ,Human-Computer Interaction ,ComputingMethodologies_PATTERNRECOGNITION ,Artificial Intelligence ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Performance measurement ,Computer Vision and Pattern Recognition ,Artificial intelligence ,business ,computer - Abstract
The imbalanced dataset is a crucial problem found in many real-world applications. Classifiers trained on these datasets tend to overfit toward the majority class, and this problem severely affects classifier accuracy. This ultimately triggers a large cost to cover the error in terms of misclassifying the minority class especially in credit-granting decision when the minority class is the bad loan applications. By comparing the industry standard with well-known machine learning and ensemble models under imbalance treatment approaches, this study shows the potential performance of these models towards the industry standard in credit scoring. More importantly, diverse performance measurements reveal different weaknesses in various aspects of a scoring model. Employing class balancing strategies can mitigate classifier errors, and both homogeneous and heterogeneous ensemble approaches yield the best significant improvement on credit scoring.
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- 2020
29. An Efficient Method for Mining Closed Potential High-Utility Itemsets
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Nguyen Hung Bui, Bay Vo, Tzung-Pei Hong, Loan T. T. Nguyen, Van-Nam Huynh, and Trinh D. D. Nguyen
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0209 industrial biotechnology ,General Computer Science ,Computer science ,knowledge discovery ,General Engineering ,Process (computing) ,Probabilistic logic ,InformationSystems_DATABASEMANAGEMENT ,02 engineering and technology ,data mining ,computer.software_genre ,020901 industrial engineering & automation ,0202 electrical engineering, electronic engineering, information engineering ,Key (cryptography) ,high-utility itemset ,020201 artificial intelligence & image processing ,General Materials Science ,Data mining ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,closed high-utility itemset ,Representation (mathematics) ,Uncertain database ,computer ,lcsh:TK1-9971 - Abstract
High-utility itemset mining (HUIM) has become a key phase of the pattern mining process, which has wide applications, related to both quantities and profits of items. Many algorithms have been proposed to mine high-utility itemsets (HUIs). Since these algorithms often return a large number of discovered patterns, a more compact and lossless representation has been proposed. The recently proposed closed high utility itemset mining (CHUIM) algorithms were designed to work with certain types of databases (e.g., those without probabilities). In fact, real-world databases might contain items or itemsets associated with probability values. To effectively mine frequent patterns from uncertain databases, several techniques have been developed, but there does not exist any method for mining CHUIs from this type of databases. This work presents a novel and efficient method without generating candidates, named CPHUI-List, to mine closed potential high-utility itemsets (CPHUIs) from uncertain databases. The proposed algorithm is DFS-based and utilizes the downward closure property of high transaction-weighted probabilistic mining to prune non-CPHUIs. It can be seen from the experiment evaluations that the proposed algorithm has better execution time and memory usage than the CHUI-Miner.
- Published
- 2020
30. A Risk Analysis Based on a Two-Stage Model of Fuzzy AHP-DEA for Multimodal Freight Transportation Systems
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Veeris Ammarapala, Van-Nam Huynh, Nantaporn Ratisoontorn, and Kwanjira Kaewfak
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Risk analysis ,0209 industrial biotechnology ,General Computer Science ,Process (engineering) ,Computer science ,risk analysis ,0211 other engineering and technologies ,Multimodal freight transportation ,02 engineering and technology ,020901 industrial engineering & automation ,DEA ,Risk analysis (business) ,Systematic risk ,Data envelopment analysis ,General Materials Science ,021103 operations research ,logistics ,General Engineering ,risk assessment ,Multiple-criteria decision analysis ,Weighting ,optimal route ,Risk analysis (engineering) ,Traffic congestion ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,lcsh:TK1-9971 - Abstract
Multimodal transportation has become a main focus of logistics systems due to environmental concerns, road safety issues, and traffic congestion. Consequently, research and policy interests in multimodal freight transportation problems are increasing. However, there are major challenges in the development of multimodal transportation associated with inherent risks and numerous uncertainties. Since risks are potential threats that directly impact logistics and transportation systems, comprehensive risk analysis should be carried out. Risk analysis is a critical process of identifying and analyzing significant issues to help industry mitigate those risks. However, identifying and prioritizing risks is more complex because of the ambiguity of the relevant data. This study proposes the integration of the fuzzy analytic hierarchy process (FAHP) and data envelopment analysis (DEA) for identifying and assessing quantitative risks. The proposed FAHP-DEA methodology uses the FAHP method to determine the weights of each risk criterion. The DEA method is employed to evaluate the linguistic variables and generate the risk scores. The simple additive weighting (SAW) method is used to aggregate risk scores under different risk criteria into an overall risk score. A case study of the coal industry demonstrates that the proposed risk analysis model is practical and allows users to more accurately prioritize risks while selecting an optimal multimodal transportation route. The process raises user's attention to the high-priority risks and is useful for industries in optimizing a multimodal transportation route under risk decision criteria.
- Published
- 2020
31. GSIC: A New Interpretable System for Knowledge Exploration and Classification
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Damminda Alahakoon, Su Nguyen, Thanh-Phu Nguyen, and Van-Nam Huynh
- Subjects
General Computer Science ,Computer science ,knowledge discovery ,02 engineering and technology ,Machine learning ,computer.software_genre ,Data modeling ,020204 information systems ,Health care ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,Representation (mathematics) ,Interpretability ,business.industry ,General Engineering ,interpretable machine learning ,Classification ,Range (mathematics) ,Binary classification ,Task analysis ,020201 artificial intelligence & image processing ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Artificial intelligence ,business ,lcsh:TK1-9971 ,computer - Abstract
Machine learning and data mining techniques have been developed rapidly in recent times. In tasks such as classification, machine learning techniques have been shown to equal to and even surpass human performance. However, high performance models are usually complex, opaque and have low interpretability thus making it difficult to explain the underlying behaviors of those models that lead to the final outcomes. In many domains such as medicine and healthcare, interpretability is one of the most important factors when considering the adoption of those models. In this paper, we propose a two-stage binary classification system applicable for healthcare (or general) data that benefits from a high level of interpretability and can at the same time achieve the results comparable to commonly used classification techniques. The motivation behind the proposed system is the lack of effective classification methods for handling data generated by various distributions (such as healthcare or banking data) that can harmonize both performance and interpretability perspectives. In this work, we tackle the problem by applying divide and conquer strategy on a new disentangled representation of the underlying data. The merit of our system is evaluated by a classification experiment with a wide range of real data and popular transparent and black-box models. Furthermore, a use case in data of sepsis patients staying in the ICU (Intensive Care Unit) is depicted to prove the interpretability of the proposed model.
- Published
- 2020
32. HEURISTICS FOR NOISE-SAFE JOB-ROTATION PROBLEMS CONSIDERING LEARNING-FORGETTING AND BOREDOM-INDUCED JOB DISSATISFACTION EFFECTS
- Author
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Pavinee Rerkjirattikal, Thepchai Supnithi, Sun Olapiriyakul, Stefano Starita, Van-Nam Huynh, and Tisana Wanwarn
- Subjects
0209 industrial biotechnology ,Environmental Engineering ,Forgetting ,Operations research ,Computer science ,02 engineering and technology ,Boredom ,Management, Monitoring, Policy and Law ,Pollution ,020901 industrial engineering & automation ,Genetic algorithm ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,020201 artificial intelligence & image processing ,Job satisfaction ,Job rotation ,medicine.symptom ,Greedy algorithm ,Heuristics ,Productivity - Abstract
In mitigating occupational hazards, there is often a need to use administrative controls such as job rotation over a prolonged period until the hazards can be eliminated or mitigated to safe levels. This research develops a noise-safe job-rotation optimization model that accounts for learning, forgetting, and boredom effects. Our analysis focuses on the case of human-paced and labor-intensive operations, considering the trade-off between safety and productivity. A case of multi-skilled workers that have heterogeneous skill levels with varying problem sizes is used to demonstrate the model s capabilities. A genetic algorithm and a randomized greedy algorithm are developed and shown to be effective in solving large-scale safe job rotation problems. Our results also show how the boredom and forgetting effects create productivity delays when job rotation is used.
- Published
- 2020
33. A Novel Hybridization of ARIMA, ANN, and K-Means for Time Series Forecasting
- Author
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Warut Pannakkong, Van-Hai Pham, and Van-Nam Huynh
- Abstract
This article aims to propose a novel hybrid forecasting model involving autoregressive integrated moving average (ARIMA), artificial neural networks (ANNs) and k-means clustering. The single models and k-means clustering are used to build the hybrid forecasting models in different levels of complexity (i.e. ARIMA; hybrid model of ARIMA and ANNs; and hybrid model of k-means, ARIMA, and ANN). To obtain the final forecasting value, the forecasted values of these three models are combined with the weights generated from the discount mean square forecast error (DMSFE) method. The proposed model is applied to three well-known data sets: Wolf's sunspot, Canadian lynx and the exchange rate (British pound to US dollar) to evaluate the prediction capability in three measures (i.e. MSE, MAE, and MAPE). In addition, the prediction performance of the proposed model is compared to ARIMA; ANNs; Khashei and Bijari's model; and the hybrid model of k-means, ARIMA, and ANN. The obtained results show that the proposed model gives the best performance in MSE, MAE, and MAPE for all three data sets.
- Published
- 2022
34. A Data-Driven Weighting Method Based on DEA Model for Evaluating Innovation Capability in Banking
- Author
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Nu Dieu Khue Ngo and Van-Nam Huynh
- Published
- 2022
35. A Topic Modeling Approach for Exploring Attraction of Dark Souls Series Reviews on Steam
- Author
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Yang Yu, Ba Hung Nguyen, Duy Tai Dinh, Fangyu Yu, Tsutomu Fujinami, and Van Nam Huynh
- Abstract
Millions of players are active on gaming service platforms such as Twitch and Steam every month, but few researchers pay attention to their comments and experience. Among many types of games, hardcore games attract game enthusiasts with highly great difficulty. Hardcore games require players to invest much time to learn, so they have the highest engagement in the game genre. The Dark Souls series has always been a landmark masterpiece in hardcore games. It attracts many hardcore players with its challenging, subversive narrative, rich gameplay, and builds. The analysis of the success of the Dark Souls series is meaningful and inspiring for game developers. Many studies have analyzed the impact of Dark Souls games on player behaviors from a psychological and cultural perspective in current Game Research. However, few studies have investigated the attraction of the Dark Souls series from the players' perspective. Therefore, this research uses a topic model on massive review data of the Dark Soul series on Steam to reveal players' concerns. It aims to explore the charm of the Dark Souls series. The Dark Souls trilogy of three games produced by From Software and are available on Steam. Steam is the most significant worldwide digital distribution platform that offers comprehensive service, including installing and automatically updating games and community features such as friends lists and groups, cloud storage, and in-game voice and chat functionality. Since both Dark Souls (DS1) and Dark Souls 3 (DS3) was highly rated in this franchise, this study focuses on the masterpiece of the trilogy: Dark Souls. In the experiment, we collected a new review dataset of the Dark Souls series from Steam, including approximately 100,000 DS3 and 23,000 DS1 reviews up to October 2021. Then we used the Latent Dirichlet Allocation (LDA) model to categorize reviews from both datasets. Consequently, we uncovered 15 and 14 topics from DS1 and DS3, respectively. Among them, we used 13 topics that appear in both games to find out topics with high frequencies and positive ratings. The results indicate that most game players are concerned with five common topics: "experience", "combat", "character", "item", and "difficulty”, which are related to in-game items and boss fight design. Specifically, these topics appear in both games with a frequency and positive rating of over 10%. We also found stratification on "device" significantly lower than other topics, reflecting the developer's less optimizing game control when DS series were ported. Generally, the analysis results from this research provide high interpretability that can further support other studies in this field.
- Published
- 2022
36. Evidence-Based Data Mining Method to Reveal Similarities between Materials Based on Physical Mechanisms
- Author
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Minh-Quyet Ha, Duong-Nguyen Nguyen, Hiori Kino, Yasunobu Ando, Takashi Miyake, Thierry Denœux, Van-Nam Huynh, and Hieu-Chi Dam
- Published
- 2022
37. Job-Satisfaction Enhancement in Nurse Scheduling: A Case of Hospital Emergency Department in Thailand
- Author
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Pavinee Rerkjirattikal, Raveekiat Singhaphandu, Van-Nam Huynh, and Sun Olapiriyakul
- Published
- 2022
38. A Hybrid Model of VMD-EMD-FFT, Similar Days Selection Method, Stepwise Regression, and Artificial Neural Network for Daily Electricity Peak Load Forecasting
- Author
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Lalitpat Aswanuwath, Warut Pannakkong, Jirachai Buddhakulsomsiri, Jessada Karnjana, and Van-Nam Huynh
- Subjects
VMD ,EDM ,Control and Optimization ,Renewable Energy, Sustainability and the Environment ,hybrid model ,Energy Engineering and Power Technology ,similar days method ,Building and Construction ,FFT ,stepwise regression ,daily peak load forecasting ,Electrical and Electronic Engineering ,Engineering (miscellaneous) ,artificial neural network ,Energy (miscellaneous) - Abstract
Daily electricity peak load forecasting is important for electricity generation capacity planning. Accurate forecasting leads to saving on excessive electricity generating capacity, while maintaining the stability of the power system. The main challenging tasks in this research field include improving forecasting accuracy and reducing computational time. This paper proposes a hybrid model involving variational mode decomposition (VMD), empirical mode decomposition (EMD), fast Fourier transform (FFT), stepwise regression, similar days selection (SD) method, and artificial neural network (ANN) for daily electricity peak load forecasting. Stepwise regression and similar days selection method are used for input variable selection. VMD and FFT are applied for data decomposition and seasonality capturing, while EMD is employed for determining an appropriate decomposition level for VMD. The hybrid model is constructed to effectively forecast special holidays, which have different patterns from other normal weekdays and weekends. The performance of the hybrid model is tested with real electricity peak load data provided by the Electricity Generating Authority of Thailand, the leading power utility state enterprise under the Ministry of Energy. Experimental results show that the hybrid model gives the best performance while saving computation time by solving the problems in input variable selection, data decomposition, and imbalance data of normal and special days in the training process.
- Published
- 2023
39. Evidence-based data mining method to reveal similarities between materials based on physical mechanisms
- Author
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Minh-Quyet Ha, Duong-Nguyen Nguyen, Viet-Cuong Nguyen, Hiori Kino, Yasunobu Ando, Takashi Miyake, Thierry Denœux, Van-Nam Huynh, and Hieu-Chi Dam
- Subjects
General Physics and Astronomy - Abstract
Measuring the similarity between materials is essential for estimating their properties and revealing the associated physical mechanisms. However, current methods for measuring the similarity between materials rely on theoretically derived descriptors and parameters fitted from experimental or computational data, which are often insufficient and biased. Furthermore, outliers and data generated by multiple mechanisms are usually included in the dataset, making the data-driven approach challenging and mathematically complicated. To overcome such issues, we apply the Dempster–Shafer theory to develop an evidential regression-based similarity measurement (eRSM) method, which can rationally transform data into evidence. It then combines such evidence to conclude the similarities between materials, considering their physical properties. To evaluate the eRSM, we used two material datasets, including 3[Formula: see text] transition metal–4[Formula: see text] rare-earth binary and quaternary high-entropy alloys with target properties, Curie temperature, and magnetization. Based on the information obtained on the similarities between the materials, a clustering technique is applied to learn the cluster structures of the materials that facilitate the interpretation of the mechanism. The unsupervised learning experiments demonstrate that the obtained similarities are applicable to detect anomalies and appropriately identify groups of materials whose properties correlate differently with their compositions. Furthermore, significant improvements in the accuracies of the predictions for the Curie temperature and magnetization of the quaternary alloys are obtained by introducing the similarities, with the reduction in mean absolute errors of 36% and 18%, respectively. The results show that the eRSM can adequately measure the similarities and dissimilarities between materials in these datasets with respect to mechanisms of the target properties.
- Published
- 2023
40. Esports Game Updates and Player Perception: Data Analysis of PUBG Steam Reviews
- Author
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Yang Yu, Ba-Hung Nguyen, Fangyu Yu, and Van-Nam Huynh
- Published
- 2021
41. Kernel-Based k-Representatives Algorithm for Fuzzy Clustering of Categorical Data
- Author
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Van-Nam Huynh and Toan Nguyen Mau
- Subjects
ComputingMethodologies_PATTERNRECOGNITION ,Fuzzy clustering ,Computer science ,Kernel (statistics) ,Fuzzy control system ,Data mining ,Cluster analysis ,computer.software_genre ,Categorical variable ,Fuzzy logic ,computer ,Group object ,Silhouette - Abstract
Fuzzy cluster analysis plays an essential role in addressing unclear boundaries between clusters in data and aims to group objects into fuzzy clusters based on their similarities. In this paper, we propose a new method for fuzzy clustering of data with categorical attributes. Specifically, we first introduce a method for kernel-based representation of cluster centers in which the underlying distribution of categorical values within a cluster center is estimated as a weighted sum of the uniform distribution and their frequency distribution. We then extend the k-centers clustering method by applying this newly proposed method of cluster center presentation for fuzzy clustering of categorical data. The effectiveness and efficiency of the proposed method are demonstrated by conducting experiments on 16 realworld datasets and comparing the results with those of existing methods. In addition, our research can be regarded as the first attempt to apply a fuzzy silhouette scoring method that includes internal coherence and external separation of fuzzy clusters into clustering of categorical data.
- Published
- 2021
42. Unsupervised hybrid anomaly detection model for logistics fleet management systems
- Author
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Thepchai Supnithi, Teerayut Horanont, Thananut Phiboonbanakit, and Van-Nam Huynh
- Subjects
Clustering high-dimensional data ,050210 logistics & transportation ,business.industry ,Process (engineering) ,Computer science ,Mechanical Engineering ,05 social sciences ,Transportation ,010501 environmental sciences ,Machine learning ,computer.software_genre ,01 natural sciences ,Overcurrent ,Set (abstract data type) ,Dimensional reduction ,0502 economics and business ,Unsupervised learning ,Anomaly detection ,Artificial intelligence ,business ,Law ,computer ,0105 earth and related environmental sciences ,General Environmental Science ,Fleet management - Abstract
Unsupervised anomaly detection in high-dimensional data is crucial for both machine learning research and industrial applications. Over the past few years, the logistics agencies’ operation efficiency decreased due to the lack of understanding how best to handle potential client requests, while current anomaly detection approaches might be inefficient in distinguishing normal and abnormal behaviours from the high-dimensional data. Although previous studies continue to improve detection models, they suffer from the inability to preserve vital information while performing a dimensional reduction process. In this study, the authors aim to improve anomaly detection by proposing an ensemble method that is built and trained on two hybrid models. Eventually, after two trained hybrid models were introduced, an ensemble probability rule was applied to combine their prediction results for performing final decision-making of anomaly detection. To demonstrate the practical use of our proposed model, we have set up a case study with a logistics agency and the experiment shows that the proposed model improved accuracy by 0.88 over current models.
- Published
- 2019
43. A weight-consistent model for fuzzy supplier selection and order allocation problem
- Author
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Pisal Yenradee, Van-Nam Huynh, and Sirin Suprasongsin
- Subjects
Decision support system ,Mathematical optimization ,021103 operations research ,Computer science ,0211 other engineering and technologies ,General Decision Sciences ,02 engineering and technology ,Management Science and Operations Research ,Multiple-criteria decision analysis ,Minimax ,Fuzzy logic ,Constraint (information theory) ,Theory of computation ,Multiple criteria ,Selection (genetic algorithm) - Abstract
Decision support for Supplier Selection and Order Allocation (SSOA) is an important application area of multiple criteria decision making (MCDM) problems. In Amid et al. (Int J Prod Econ 131(1):139–145, 2011) proposed and developed a weighted maximin model to ensure the weight-consistent solution for SSOA in an MCDM problem under an uncertain environment. Essentially, this model is based on a weight-consistent constraint and a maximin aggregation operator. This paper reanalyzes the weighted maximin model in terms of the weight-consistent constraint, and then proposes a general weight-consistent model for SSOA in MCDM problems under uncertainty. In this paper, two existing models are reviewed and compared with the proposed model. Three datasets with different ranges of fuzzy demand and full factorial patterns of criteria weights are used to test the performances of the related models. The results showed that the proposed model always generates a weight-consistent Pareto-optimal solution in all cases, while the other existing models do not.
- Published
- 2019
44. An uncertain target-oriented QFD approach to service design based on service standardization with an application to bank window service
- Author
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Hong-Bin Yan, Tieju Ma, Van-Nam Huynh, and Xiang-Sheng Meng
- Subjects
Service (business) ,Operations research ,Standardization ,business.industry ,Computer science ,Service design ,Interpretation (philosophy) ,Probabilistic logic ,Window (computing) ,business ,Industrial and Manufacturing Engineering ,Quality function deployment - Abstract
This article proposes an uncertain target-oriented QFD approach to service standardization-based service design with an application to bank window service, based on a probabilistic interpretation o...
- Published
- 2019
45. A novel non-parametric method for time series classification based on k-Nearest Neighbors and Dynamic Time Warping Barycenter Averaging
- Author
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Van-Nam Huynh, Hien T. Nguyen, Tuan Minh Tran, and Xuan-May Thi Le
- Subjects
Time series classification ,0209 industrial biotechnology ,Dynamic time warping ,Series (mathematics) ,Computer science ,Nonparametric statistics ,Centroid ,02 engineering and technology ,k-nearest neighbors algorithm ,020901 industrial engineering & automation ,Artificial Intelligence ,Control and Systems Engineering ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Electrical and Electronic Engineering ,Algorithm - Abstract
Time series classification is one of the most important issues in time series data mining. This problem has attracted more and more attention of researchers in recent years. Among proposed methods in literature, 1-Nearest Neighbor (1-NN), its variants and improvements have been widely considered as hard to be beaten on classification of time series. In this paper, we propose a novel non-parametric method to classify time series. The proposed method, namely Weighted Local Dynamic Time Warping Barycenter Averaging k -Nearest Neighbors (WLDBAk-NN), is an improvement of Local Mean-based k -Nearest Neighbors (LMk-NN) algorithm. It improves LM k -NN in that it replaces the local mean vectors by local Dynamic Time Warping Barycenter (DBA) vectors calculated using our method, namely Weighted DBA (WDBA). By experiments, we show that (i) WLDBAk-NN outperforms the Weighted Local Mean-based k -Nearest Neighbors (WLMk-NN) algorithm, and (ii) both WLMk-NN and WLDBAk-NN outperform 1-NN, LMk-NN, k -Nearest Centroid Neighbors (k-NCN), and LMk-NCN in 85 time series datasets of UCR Time Series Classification Archive. The experimental results also show that new local mean vectors used in WLMk-NN and WLDBAk-NN significantly contribute to the improvement of the performance of time series classification.
- Published
- 2019
46. How collaborative routines improve dynamic innovation capability and performance in tourism industry? A path-dependent learning model
- Author
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Akkaranan Pongsathornwiwat, Kalaya Udomvitid, Chawalit Jeenanunta, and Van-Nam Huynh
- Subjects
Knowledge Search ,Knowledge management ,Computer science ,business.industry ,05 social sciences ,Geography, Planning and Development ,Knowledge sharing ,Absorptive capacity ,Tourism, Leisure and Hospitality Management ,0502 economics and business ,050211 marketing ,Performance improvement ,business ,050212 sport, leisure & tourism ,Tourism ,Path dependent - Abstract
Current results of direct relationships between collaboration and innovation capability on performance in tourism contexts are inconsistent. This research is to uncover roles of collaborative routi...
- Published
- 2019
47. Evidence-based recommender system and experimental validation for high-entropy alloys
- Author
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Hieu-Chi Dam, Takahiro Nagata, Van-Nam Huynh, Nguyen-Duong Nguyen, Minh-Quyet Ha, Viet-Cuong Nguyen, Hiori Kino, Thierry Denœux, Takashi Miyake, and Toyohiro Chikyow
- Subjects
Computer science ,High entropy alloys ,Experimental validation ,Data mining ,Recommender system ,computer.software_genre ,computer - Abstract
We present a data-driven approach to explore high-entropy alloys (HEAs). To overcome the challenges with numerous element-combination candidates, selecting appropriate descriptors, and the limitations and biased of existing data, we apply the evidence theory to develop a descriptor-free evidence-based recommender system (ERS) for recommending HEAs. The proposed system measures the similarities between element combinations and utilizes it to recommend potential HEAs. To evaluate the ERS, we compare its HEA-recommendation capability with those of matrix-factorization- and supervised-learning-based recommender systems on four widely known data sets, including binary and ternary alloys. The results of experiments using k-fold cross-validation on the data sets show that the ERS outperforms all competitors. Furthermore, the ERS shows excellent extrapolation capabilities in experiments of recommending quaternary and quinary HEAs. We experimentally validate the most strongly recommended Fe-Co-based magnetic HEA, viz. FeCoMnNi, and confirm that it shows a body-centered cubic structure and is stable at high temperatures.
- Published
- 2021
48. Multi-objective Optimization of Freight Route Choices in Multimodal Transportation
- Author
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Kwanjira Kaewfak, Veeris Ammarapala, and Van-Nam Huynh
- Subjects
Zero-one goal programing ,General Computer Science ,Operations research ,Analytic hierarchy process ,Computer science ,Route selection ,QA75.5-76.95 ,Multi-objective optimization ,Computational Mathematics ,Electronic computers. Computer science ,Multimodal freight transportation system ,Risk assessment - Abstract
Route selection strategy has become the main aspect in the multimodal transportation system. The transport cost and time as well as the inherent risks must be considered when determining a corrective design plan. The selection of a multimodal transportation network route is a complex multi-objective decision problem. Therefore, considering the impact factors such as the transport cost, time, and comprehensive risk assessment model were further created. This paper develops a decision support model using an analytic hierarchy process (AHP) and zero-one goal programing (ZOGP) to determine an optimal multimodal transportation route. AHP is employed to determine weights of each factor, which rely on expert judgments. The significant weights of criteria obtained from AHP can be integrated in the objective function of ZOGP which is used to generate the optimal route. The empirical case study of coal manufacturing is conducted to demonstrate the proposed model. This methodology can provide a guidance for effectively determining the multimodal transportation routes to improve performance of logistics systems.
- Published
- 2021
49. Topics in Financial Filings and Bankruptcy Prediction with Distributed Representations of Textual Data
- Author
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Van-Nam Huynh, Ba-Hung Nguyen, and Shirai Kiyoaki
- Subjects
Finance ,Topic model ,Bankruptcy ,business.industry ,Simple (abstract algebra) ,Computer science ,Bankruptcy prediction ,Embedding ,business ,Classifier (UML) ,Distributed representation - Abstract
We uncover latent topics embedded in the management discussion and analysis (MD&A) of financial reports from the listed companies in the US, and we examine the evolution of topics found by a dynamic topic modelling method - Dynamic Embedding Topic Model. Using more than 203k reports with 40M sentences ranging from 1997 to 2017, we find 30 interpretable topics. The evolution of topics follows economics cycles and major industrial events. We validate the significance of these latent topics by the state-of-the-art performance of a simple bankruptcy ensemble classifier trained on both novel features - topical distributed representation of the MD&A, and accounting features.
- Published
- 2021
50. Analyzing the Relationship Between Service Innovation and Customer Value Co-creation Intention: The Case of Mobile Banking
- Author
-
Nu Dieu Khue Ngo, Youji Kohda, and Van-Nam Huynh
- Subjects
Uncertainty avoidance ,Service (business) ,Mobile banking ,Knowledge management ,business.industry ,Information sharing ,Hofstede's cultural dimensions theory ,Business ,Service innovation ,Exploratory factor analysis ,Likert scale - Abstract
Customer value co-creation plays an important role in creating desired values that can better satisfy customer needs. However, there are few studies on the relationship between service innovation and customer value co-creation. This study aims to investigate the influence of mobile banking service innovation (concept, technology, and process) on customer value co-creation intention (information sharing and feedback), and how such effects are moderated by cultural values (power distance, collectivism, masculinity, and uncertainty avoidance). Data was collected via questionnaires sent to customers using the mobile banking service of banks in Vietnam. The participants were requested to response to each question using a five-point Likert scale. The data was then analyzed by exploratory factor analysis, reliability analysis, and hierarchical regression analysis. The findings could enable appropriate strategies to facilitate customer value co-creation to be identified.
- Published
- 2021
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