• Title/Summary/Keyword: Network selection

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Determination Method of TTL for Improving Energy Efficiency of Wormhole Attack Defense Mechanism in WSN (무선 센서 네트워크에서 웜홀 공격 방어기법의 에너지 효율향상을 위한 TTL 결정 기법)

  • Lee, Sun-Ho;Cho, Tae-Ho
    • Journal of the Korea Society for Simulation
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    • v.18 no.4
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    • pp.149-155
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    • 2009
  • Attacks in wireless sensor networks (WSN), are similar to the attacks in ad-hoc networks because there are deployed on a wireless environment. However existing security mechanism cannot apply to WSN, because it has limited resource and hostile environment. One of the typical attack in WSN is setting up wrong route that using wormhole. To overcome this threat, Ji-Hoon Yun et al. proposed WODEM (WOrmhole attack DEfense Mechanism) which can detect and counter with wormhole. In this scheme, it can detect and counter with wormhole attacks by comparing hop count and initial TTL (Time To Live) which is pre-defined. The selection of a initial TTL is important since it can provide a tradeoff between detection ability ratio and energy consumption. In this paper, we proposed a fuzzy rule-based system for TTL determination that can conserve energy, while it provides sufficient detection ratio in wormhole attack.

Research on Urban Air Mobility Operations Optimization Research Trends (도심항공교통(Urban Air Mobility) 운영 최적화 연구 동향에 관한 연구)

  • Jibok Chung
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.701-706
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    • 2023
  • The Korean government and industry have presented a roadmap for the commercialization of UAM services and are promoting it in earnest. In order to introduce full-scale UAM services, there are various issues to be solved, such as the development of high-performance aircraft, the design of network bases and corridors, the optimization of operation management, and the establishment of related laws and systems. In this study, in terms of optimizing operation management, we will examine research trends by field, focusing on Korea, and derive research topics that need to be solved in the future. Korean researchers have suggested that research is centered on UAM service usage fees, usage intentions and acceptance models, and vertiport location selection, but operational optimization studies such as service order acceptance, aircraft repositioning, and battery charging and maintenance scheduling are needed in the future.

A Study on the Effective Selection of Tunnel Reinforcement Methods using Decision Tree Technique (의사결정트리 기법을 이용한 터널 보조공법 선정방안 연구)

  • Kim, Jong-Gyu;Sagong, Myung;Lee, Jun S.;Lee, Yong-Joo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4C
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    • pp.255-264
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    • 2006
  • The auxiliary reinforcement method is normally applied to prevent a possible collapse of the tunnel face where the ground condition is not favorable or geologic information is not sufficient. Recently, several engineering approaches have been made to choose the effective reinforcement methods using expert system such as neural network and fuzzy theory field, among others. Even if the expert system has offered many decision aid tools to properly select the reinforcement method, the quantitative assessment items are not easy to estimate and this is why the data mining technique, widely used in the field of social science, medical treatment, banking and agriculture, is introduced in this study. Using decision tree together with PDA, the decision aids for reinforcement method based on field construction data are created to derive the field rules and future study will be concentrated on the application of the proposed methods in a variety of underground development cases.

Selection of Key Management Targets for Claim Causes through Relational Analysis on the Causes of Change Order Claims

  • Min, Kwang-Ho;Ko, Gun-Ho;Jin, Chengquan;Hyun, Chang-Taek;Han, Sang-Won
    • International conference on construction engineering and project management
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    • 2017.10a
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    • pp.281-290
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    • 2017
  • As various stakeholders are involved in construction projects, disputes between the parties are more likely to occur, which is a very important issue for the participants in the projects. Claims in construction projects, however, are very complex and thus difficult to manage. In particular, as the cause of a claim in the preceding stage that has not been resolved in a timely manner has an effect on the cause of a claim in the following stage, it is difficult to find a point of compromise regarding a claim caused by the relationship between the causes that occur in the preceding and following stages. In this regard, this study sought to examine the rules for the generation of change order claims, which occur most frequently among the construction claims, and thus to select the key management targets through the analysis of the relationship between the causes of claims arising in the preceding and following stages for the efficient management of claims. It is expected that the use of rules for the generation of change order claims as well as of representative and similar cases will help the construction practitioners in judging claims, considering the relationships among the causes of the claims. Meanwhile, in this study, association analysis was conducted regarding the causes of the occurrence of change order claims in a design-build delivery method, and therefore, it is necessary to verify the effectiveness of the method when applied to other delivery methods.

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Convolutional neural networks for automated tooth numbering on panoramic radiographs: A scoping review

  • Ramadhan Hardani Putra;Eha Renwi Astuti;Aga Satria Nurrachman;Dina Karimah Putri;Ahmad Badruddin Ghazali;Tjio Andrinanti Pradini;Dhinda Tiara Prabaningtyas
    • Imaging Science in Dentistry
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    • v.53 no.4
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    • pp.271-281
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    • 2023
  • Purpose: The objective of this scoping review was to investigate the applicability and performance of various convolutional neural network (CNN) models in tooth numbering on panoramic radiographs, achieved through classification, detection, and segmentation tasks. Materials and Methods: An online search was performed of the PubMed, Science Direct, and Scopus databases. Based on the selection process, 12 studies were included in this review. Results: Eleven studies utilized a CNN model for detection tasks, 5 for classification tasks, and 3 for segmentation tasks in the context of tooth numbering on panoramic radiographs. Most of these studies revealed high performance of various CNN models in automating tooth numbering. However, several studies also highlighted limitations of CNNs, such as the presence of false positives and false negatives in identifying decayed teeth, teeth with crown prosthetics, teeth adjacent to edentulous areas, dental implants, root remnants, wisdom teeth, and root canal-treated teeth. These limitations can be overcome by ensuring both the quality and quantity of datasets, as well as optimizing the CNN architecture. Conclusion: CNNs have demonstrated high performance in automated tooth numbering on panoramic radiographs. Future development of CNN-based models for this purpose should also consider different stages of dentition, such as the primary and mixed dentition stages, as well as the presence of various tooth conditions. Ultimately, an optimized CNN architecture can serve as the foundation for an automated tooth numbering system and for further artificial intelligence research on panoramic radiographs for a variety of purposes.

Immunotherapy for Non-small Cell Lung Cancer: Current Landscape and Future Perspectives

  • Sun Min Lim;Min Hee Hong;Hye Ryun Kim
    • IMMUNE NETWORK
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    • v.20 no.1
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    • pp.10.1-10.14
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    • 2020
  • Immune checkpoint inhibitors (ICIs) have shown remarkable benefit in the treatment of patients with non-small-cell lung cancer (NSCLC) and have emerged as an effective treatment option even in the first-line setting. ICIs can block inhibitory pathways that restrain the immune response against cancer, restoring and sustaining antitumor immunity. Currently, there are 4 PD-1/PD-L1 blocking agents available in clinics, and immunotherapy-based regimen alone or in combination with chemotherapy is now preferred option. Combination trials assessing combination of ICIs with chemotherapy, targeted therapy and other immunotherapy are ongoing. Controversies remain regarding the use of ICIs in targetable oncogene-addicted subpopulations, but their initial treatment recommendations remained unchanged, with specific tyrosine kinase inhibitors as the choice. For the majority of patients without targetable driver oncogenes, deciding between therapeutic options can be difficult due to lack of direct cross-comparison studies. There are continuous efforts to find predictive biomarkers to find those who respond better to ICIs. PD-L1 protein expressions by immunohistochemistry and tumor mutational burden have emerged as most well-validated biomarkers in multiple clinical trials. However, there still is a need to improve patient selection, and to establish the most effective concurrent or sequential combination therapies in different NSCLC clinical settings. In this review, we will introduce currently used ICIs in NSCLC and analyze most recent trials, and finally discuss how, when and for whom ICIs can be used to provide promising avenues for lung cancer treatment.

Genetic diversity and phylogenetic relationship of Angus herds in Hungary and analyses of their production traits

  • Judit Marton;Ferenc Szabo;Attila Zsolnai;Istvan Anton
    • Animal Bioscience
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    • v.37 no.2
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    • pp.184-192
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    • 2024
  • Objective: This study aims to investigate the genetic structure and characteristics of the Angus cattle population in Hungary. The survey was performed with the assistance of the Hungarian Hereford, Angus, Galloway Association (HHAGA). Methods: Genetic parameters of 1,369 animals from 16 Angus herds were analyzed using the genotyping results of 12 microsatellite markers with the aid of PowerMarker, Genalex, GDA-NT2021, and STRUCTURE software. Genotyping of DNA was performed using an automated genetic analyzer. Based on pairwise identity by state values of animals, the Python networkx 2.3 library was used for network analysis of the breed and to identify the central animals. Results: The observed numbers of alleles on the 12 loci under investigation ranged from 11 to 18. The average effective number of alleles was 3.201. The overall expected heterozygosity was 0.659 and the observed heterozygosity was 0.710. Four groups were detected among the 16 Angus herds. The breeders' information validated the grouping results and facilitated the comparison of birth weight, age at first calving, number of calves born and productive lifespan data between the four groups, revealing significant differences. We identified the central animals/herd of the Angus population in Hungary. The match of our group descriptions with the phenotypic data provided by the breeders further underscores the value of cooperation between breeders and researchers. Conclusion: The observation that significant differences in the measured traits occurred among the identified groups paves the way to further enhancement of breeding efficiency. Our findings have the potential to aid the development of new breeding strategies and help breeders keep the Angus populations in Hungary under genetic supervision. Based on our results the efficient use of an upcoming genomic selection can, in some cases, significantly improve birth weight, age at first calving, number of calves born and the productive lifespan of animals.

Apply evolved grey-prediction scheme to structural building dynamic analysis

  • Z.Y. Chen;Yahui Meng;Ruei-Yuan Wang;Timothy Chen
    • Structural Engineering and Mechanics
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    • v.90 no.1
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    • pp.19-26
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    • 2024
  • In recent years, an increasing number of experimental studies have shown that the practical application of mature active control systems requires consideration of robustness criteria in the design process, including the reduction of tracking errors, operational resistance to external disturbances, and measurement noise, as well as robustness and stability. Good uncertainty prediction is thus proposed to solve problems caused by poor parameter selection and to remove the effects of dynamic coupling between degrees of freedom (DOF) in nonlinear systems. To overcome the stability problem, this study develops an advanced adaptive predictive fuzzy controller, which not only solves the programming problem of determining system stability but also uses the law of linear matrix inequality (LMI) to modify the fuzzy problem. The following parameters are used to manipulate the fuzzy controller of the robotic system to improve its control performance. The simulations for system uncertainty in the controller design emphasized the use of acceleration feedback for practical reasons. The simulation results also show that the proposed H∞ controller has excellent performance and reliability, and the effectiveness of the LMI-based method is also recognized. Therefore, this dynamic control method is suitable for seismic protection of civil buildings. The objectives of this document are access to adequate, safe, and affordable housing and basic services, promotion of inclusive and sustainable urbanization, implementation of sustainable disaster-resilient construction, sustainable planning, and sustainable management of human settlements. Simulation results of linear and non-linear structures demonstrate the ability of this method to identify structures and their changes due to damage. Therefore, with the continuous development of artificial intelligence and fuzzy theory, it seems that this goal will be achieved in the near future.

Exploring the phenomenon of veganphobia in vegan food and vegan fashion (비건 음식과 비건 패션에서 나타난 비건포비아 현상에 대한 탐구)

  • Yeong-Hyeon Choi;Sangyung Lee
    • The Research Journal of the Costume Culture
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    • v.32 no.3
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    • pp.381-397
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    • 2024
  • This study investigates the negative perceptions (veganphobia) held by consumers toward vegan diets and fashion and aims to foster a genuine acceptance of ethical veganism in consumption. The textual data web-crawled Korean online posts, including news articles, blogs, forums, and tweets, containing keywords such as "contradiction," "dilemma," "conflict," "issues," "vegan food" and "vegan fashion" from 2013 to 2021. Data analysis was conducted through text mining, network analysis, and clustering analysis using Python and NodeXL programs. The analysis revealed distinct negative perceptions regarding vegan food. Key issues included the perception of hypocrisy among vegetarians, associations with specific political leanings, conflicts between environmental and animal rights, and contradictions between views on companion animals and livestock. Regarding the vegan fashion industry, the eco-friendliness of material selection and design processes were seen as the pivotal factors shaping negative attitudes. Furthermore, the study identified a shared negative perception regarding vegan food and vegan fashion. This negativity was characterized by confusion and conflicts between animal and environmental rights, biased perceptions linked to specific political affiliations, perceived self-righteousness among vegetarians, and general discomfort toward them. These factors collectively contributed to a broader negative perception of vegan consumption. In conclusion, this study is significant in understanding the complex perceptions and attitudes that con- sumers hold toward vegan food and fashion. The insights gained from this research can aid in the design of more effective campaign strategies aimed at promoting vegan consumerism, ultimately contributing to a more widespread acceptance of ethical veganism in society.

Traffic Forecasting Model Selection of Artificial Neural Network Using Akaike's Information Criterion (AIC(AKaike's Information Criterion)을 이용한 교통량 예측 모형)

  • Kang, Weon-Eui;Baik, Nam-Cheol;Yoon, Hye-Kyung
    • Journal of Korean Society of Transportation
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    • v.22 no.7 s.78
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    • pp.155-159
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    • 2004
  • Recently, there are many trials about Artificial neural networks : ANNs structure and studying method of researches for forecasting traffic volume. ANNs have a powerful capabilities of recognizing pattern with a flexible non-linear model. However, ANNs have some overfitting problems in dealing with a lot of parameters because of its non-linear problems. This research deals with the application of a variety of model selection criterion for cancellation of the overfitting problems. Especially, this aims at analyzing which the selecting model cancels the overfitting problems and guarantees the transferability from time measure. Results in this study are as follow. First, the model which is selecting in sample does not guarantees the best capabilities of out-of-sample. So to speak, the best model in sample is no relationship with the capabilities of out-of-sample like many existing researches. Second, in stability of model selecting criterion, AIC3, AICC, BIC are available but AIC4 has a large variation comparing with the best model. In time-series analysis and forecasting, we need more quantitable data analysis and another time-series analysis because uncertainty of a model can have an effect on correlation between in-sample and out-of-sample.