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Estimation of the Source Adult Population for Agrotis ipsilon (Lepidoptera: Noctuidae) Appearing in Early Spring in Korea: An Approach with Phenology Modeling (국내에서 이른 봄 출현하는 검거세미밤나방 성충집단의 기원 추정: 페놀로지 모형을 통한 접근)

  • Sori Choi;Jinwoo Heo;Subin Kim;Myeongeun Jwa;Yonggyun Shin;Dong-Soon Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.1
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    • pp.37-47
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    • 2023
  • The black cutworm, Agrotis ipsilon (Hufnagel), is an important crop pest worldwide that feeds more than 80 plant species including cabbage, potato, maize, wheat and bean, and this moth is a typical pest attacking underground parts of crops. It has been known in farm booklets that the larvae of A. ipsilon overwinter in the soil in Korea, but no definitive data exist yet. This study was conducted to evaluate that the specific appearance time of A. ipsilon observed actually in the field could be explained when we assumed that this pest overwinters in a form of larvae or pupae. Degree day-based phenology models were applied for tracking forward or backward to find the predicted developmental stage which developed at a specific stage found in the field. As a result of the analysis, it was confirmed that an initial population could be established in a group that does not overwinter as larvae or pupae in Korea. In other words, the appearance of adults in early March to April could not be explained by the presence of domestic overwintering populations. Populations that overwinter as larvae or pupae in Korea were able to emerge as adults in June to July at the earliest. Therefore, the group of adults appearing in early spring is highly likely to be a population that migrated from outside Korea. Taken together, it was estimated that the colony of A. ipsilon in Korea would be formed by a mixture of a migrant population through long-distance migration and a overwintering population.

A Study on 3D Virtual Restoration and Convergence Utilization of Gas Masks for Digital Reproduction of War Cultural Heritage (전쟁 문화유산 디지털 재현을 위한 방독면 3D 가상 복원 및 융합 활용 연구)

  • Hyoung-Ki Ahn;Seung-Jun Oh;Ho-Yeon Lee;Young-Guy Lee
    • Journal of Internet of Things and Convergence
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    • v.9 no.1
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    • pp.89-95
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    • 2023
  • In January 2007, the Remains Excavation and Investigation Team of the Ministry of National Defense was established, and full-scale excavation of remains was promoted. Currently, the scope of the excavation is being expanded to Baekma Hill within the DMZ, where fierce battles were fought during the Korean War. Now, many remains and remains are being excavated in Baekma hill. Most are in damaged condition. Therefore, in this study, the original form of the excavated remains was restored using 3D scanning and 3D modeling. This digital restoration method can be an alternative to compensate for the disadvantages of the manual method. Currently, various digital restorations using 3D technology are active in the field of cultural heritage. Digitally restored materials can be used as basic data for digital heritage. Based on this, various contents related to excavation of remains and patriots and veterans can be developed. Furthermore, if digital human restoration is made based on the excavated remains, it will be possible to reproduce the appearance of the dead.

Variation of Earth Pressure Acting on Cut-and-Cover Tunnel Lining with Settlement of Backfill (되메움토의 침하에 따른 개착식 터널 라이닝에 작용하는 토압의 변화)

  • Bautista F.E.;Park Lee-Keun;Im Jong-Chul;Lee Young-Nam
    • Journal of the Korean Geotechnical Society
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    • v.22 no.6
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    • pp.27-40
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    • 2006
  • Damage of cut-and-cover tunnel lining can be attributed to physical and mechanical factors. Physical factors include material property, reinforcement corrosion, etc. while mechanical factors include underground water pressure, vehicle loads, etc. This study is limited to the modeling of rigid circular cut and cover tunnel constructed at a depth of $1.0{\sim}1.5D$ in loose sandy ground and subjected to a vibration frequency of 100 Hz. In this study, only damages due to mechanical factors in the form of additional loads were considered. Among the different types of additional, excessive earth pressure acting on the cut-and-cover tunnel lining is considered as one of the major factors that induce deformation and damage of tunnels after the construction is completed. Excessive earth pressure may be attributed to insufficient compaction, consolidation due to self-weight of backfill soil, precipitation and vibration caused by traffic. Laboratory tunnel model tests were performed in order to determine the earth pressure acting on the tunnel lining and to investigate the applicability of existing earth pressure formulas. Based on the difference in the monitored and computed earth pressure, a factor of safety was recommended. Soil deformation mechanism around the tunnel was also presented using the picture analysis method.

Effects of particle size and loading rate on the tensile failure of asphalt specimens based on a direct tensile test and particle flow code simulation

  • Q. Wang;D.C. Wang;J.W. Fu;Vahab Sarfarazi;Hadi Haeri;C.L. Guo;L.J. Sun;Mohammad Fatehi Marji
    • Structural Engineering and Mechanics
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    • v.86 no.5
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    • pp.607-619
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    • 2023
  • This study, it was tried to evaluate the asphalt behavior under tensile loading conditions through indirect Brazilian and direct tensile tests, experimentally and numerically. This paper is important from two points of view. The first one, a new test method was developed for the determination of the direct tensile strength of asphalt and its difference was obtained from the indirect test method. The second one, the effects of particle size and loading rate have been cleared on the tensile fracture mechanism. The experimental direct tensile strength of the asphalt specimens was measured in the laboratory using the compression-to-tensile load converting (CTLC) device. Some special types of asphalt specimens were prepared in the form of slabs with a central hole. The CTLC device is then equipped with this specimen and placed in the universal testing machine. Then, the direct tensile strength of asphalt specimens with different sizes of ingredients can be measured at different loading rates in the laboratory. The particle flow code (PFC) was used to numerically simulate the direct tensile strength test of asphalt samples. This numerical modeling technique is based on the versatile discrete element method (DEM). Three different particle diameters were chosen and were tested under three different loading rates. The results show that when the loading rate was 0.016 mm/sec, two tensile cracks were initiated from the left and right of the hole and propagated perpendicular to the loading axis till coalescence to the model boundary. When the loading rate was 0.032 mm/sec, two tensile cracks were initiated from the left and right of the hole and propagated perpendicular to the loading axis. The branching occurs in these cracks. This shows that the crack propagation is under quasi-static conditions. When the loading rate was 0.064 mm/sec, mixed tensile and shear cracks were initiated below the loading walls and branching occurred in these cracks. This shows that the crack propagation is under dynamic conditions. The loading rate increases and the tensile strength increases. Because all defects mobilized under a low loading rate and this led to decreasing the tensile strength. The experimental results for the direct tensile strengths of asphalt specimens of different ingredients were in good accordance with their corresponding results approximated by DEM software.

The Effects of Non Verbal Communication of Restaurant Employees on Customer Emotion, Customer Satisfaction, Customer Trust, and Revisit Intention (외식업 직원의 비언어적 커뮤니케이션이 고객감정, 고객만족, 고객신뢰 그리고 재방문의도에 미치는 영향)

  • Kim, Bo-Yeong;Jun, Jae-Hyeon;Han, Sang-Ho
    • The Korean Journal of Franchise Management
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    • v.9 no.3
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    • pp.45-55
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    • 2018
  • Purpose - Non-verbal Communication with customers in restaurant business can play an important role because it affects customer behavior and attitudes as a means to develop and maintain long-term relationships with customers. The purpose of this study is to analyze the effect of non-verbal communication with customers and the effect of the influence on customer satisfaction, trust, and revisit intention. Research design, data, methodology - In order to verify the research models and hypotheses of this study, questions were prepared for each variable and data were collected through questionnaires. The questionnaire survey was conducted from March 27, 2018 to April 17, 2018, for those who agreed with the citizens of the Jeju area who visited the restaurant recently. 50 out of 100 were conducted by internet survey and 50 were surveyed. Thus, a total of 100 responses were used using structural equation modeling with Smartpls 3.0. Results - The results of the study are as follows. First, non-verbal communication has a significant impact on customer emotion. Second customer emotion have a significant impact on customer trust and satisfaction. Third, Customer satisfaction had positive a significant effect on revisit intention. Fourth, Customer trust had positive a significant effect on revisit intention. Conclusions - The implications of this study are following as: The food service company should continuously provide non-verbal communication training to employees so that they can respond to customers with the right attitude and bright smile. In particular, in the case of restaurant franchises, customer response manuals should be created and distributed to the franchisees, and a regular training program for the franchisees should be implemented to provide the same service to the customer. Second, CEOs should have to worry about what kind of experience he or she has left since leaving the store. It is also necessary to constantly look at what customers experience in their stores or in their brands, and what emotions they form through their experiences. Third, the more satisfied or trusted customers are formed through the service of the employee, the more loyal the restaurant business will be, and the more likely it is to make continuous revisit and positive word-of-mouth activities..

Dynamic Load Allowance of Highway Bridges by Numerical Dynamic Analysis for LRFD Calibration (LRFD 보정을 위한 동적해석에 의한 도로교의 동적하중허용계수)

  • Chung, Tae Ju;Shin, Dong-Ku;Park, Young-Suk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3A
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    • pp.305-313
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    • 2008
  • A reliability based calibration of dynamic load allowance (DLA) of highway bridge is performed by numerical dynamic analysis of various types of bridges taking into account of the road surface roughness and bridge-vehicle interaction. A total of 10 simply supported bridges with three girder types in the form of prestressed concrete girder, steel plate girder, and steel box girder is analyzed. The cross sections recommended in "The Standardized Design of Highway Bridge Superstructure" by the Korean Ministry of Construction are used for the prestressed concrete girder bridges and steel plate girder bridges while the box girder bridges are designed by the LRFD method. Ten sets of road surface roughness for each bridge are generated from power spectral density (PSD) function by assuming the roadway as "Average Road". A three dimensionally modeled 5-axle tractor-trailer with its gross weight the same as that of DB-24 design truck is used in the dynamic analysis. For the finite element modeling of superstructure, beam elements for the main girder, shell elements for concrete deck, and rigid links between main girder and concrete deck are used. The statistical mean and coefficient of variation of DLA are obtained from a total of 100 DLA results for 10 different bridges with each having 10 sets of road surface roughness. Applying the DLA statistics obtained, the DLA is finally calibrated in a reliability based LRFD format by using the formula developed in the calibration of OHBDC code.

Modeling the Effect of Consideration Set-Based Reference Price: Empirical Bayes & Latent Class Approach (고려상품군을 반영한 준거가격효과의 모형화: Empirical Bayes & Latent Class Approach)

  • Chang, Kwangpil
    • Asia Marketing Journal
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    • v.8 no.1
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    • pp.1-17
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    • 2006
  • A couple of previous studies have warned against the use of homogeneous choice models in assessing the effect of reference price since unaccounted for response heterogeneity may result in spurious reference price effects(Chang, Siddarth and Weinberg 1999; Bell and Lattin 2000). According to Meyer and Kahn(1991), not accounting for consideration set heterogeneity may also bias the effect parameters in the choice model. Therefore, failure to account for these two sources of bias, in fact, have cast doubt on the empirical support for reference price effects in general. In view of aforementioned potential sources of bias, the author investigates the robustness of loss aversion effect in the reference-dependent model after accounting for heterogeneity in response as well as consideration set. The proposed model defines individual household's consideration set based on the posterior distribution of preference obtained from the Empirical Bayes approach. In addition, the same posterior distribution is used to form household-specific reference prices. Response heterogeneity correction is carried out via the Latent Class approach. The proposed model outperforms the Reference-Dependent model that includes the reference price measure most often employed in the previous studies. This implies that as a way of simplifying decision task, consumers restrict their consideration set to a subset of available brands not only in making a brand choice but also in forming reference prices.

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Comparative analysis of the digital circuit designing ability of ChatGPT (ChatGPT을 활용한 디지털회로 설계 능력에 대한 비교 분석)

  • Kihun Nam
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.967-971
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    • 2023
  • Recently, a variety of AI-based platform services are available, and one of them is ChatGPT that processes a large quantity of data in the natural language and generates an answer after self-learning. ChatGPT can perform various tasks including software programming in the IT sector. Particularly, it may help generate a simple program and correct errors using C Language, which is a major programming language. Accordingly, it is expected that ChatGPT is capable of effectively using Verilog HDL, which is a hardware language created in C Language. Verilog HDL synthesis, however, is to generate imperative sentences in a logical circuit form and thus it needs to be verified whether the products are executed properly. In this paper, we aim to select small-scale logical circuits for ease of experimentation and to verify the results of circuits generated by ChatGPT and human-designed circuits. As to experimental environments, Xilinx ISE 14.7 was used for module modeling, and the xc3s1000 FPGA chip was used for module embodiment. Comparative analysis was performed on the use area and processing time of FPGA to compare the performance of ChatGPT products and Verilog HDL products.

A Study on the Development of Mathematical-Informatics Linkage·Convergence Class Materials according to the Theme-Based Design Model (주제기반 설계 모형에 따른 수학-정보 연계·융합 수업 자료 개발 연구)

  • Lee, Dong Gun;Kim, Han Su
    • Communications of Mathematical Education
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    • v.37 no.3
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    • pp.517-544
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    • 2023
  • This study presents the process and outcomes of developing mathematical-informatics linkage·convergence class materials, based on previous research findings that indicate a lack of such materials in high schools despite the increasing need for development of interdisciplinary linkage·convergence class materials In particular, this research provides insights into the discussions of six teachers who participated in the same professional learning community program, aiming to create materials that are suitable for linkage·convergence class materials and highly practical for classroom implementation. Following the material development process, a theme-based design model was applied to create the materials. In alignment with prior research and consensus among teacher learning community members, mathematics and informatics teachers developed instructional materials that can be utilized together during a 100-minute block lesson. The developed materials utilize societal issue contexts to establish links between the two subjects, enabling students to engage in problem-solving through mathematical modeling and coding. To increase the validity and practicality of the developed resources during their field application, CVR verification was conducted involving field teachers. Incorporating the results of the CVR verification, the finalized instructional materials were presented in the form of a teaching guide. Furthermore, we aimed to provide insights into the trial-and-error experiences and deliberations of the developers throughout the material development process, with the intention of offering valuable information that can serve as a foundation for conducting related research by field researchers. These research findings hold value as empirical evidence that can explore the applicability of teaching material development models in fields. The accumulation of such materials is expected to facilitate a cyclical relationship between theoretical teaching models and practical classroom applications.

Analysis of Research Trends in Deep Learning-Based Video Captioning (딥러닝 기반 비디오 캡셔닝의 연구동향 분석)

  • Lyu Zhi;Eunju Lee;Youngsoo Kim
    • KIPS Transactions on Software and Data Engineering
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    • v.13 no.1
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    • pp.35-49
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    • 2024
  • Video captioning technology, as a significant outcome of the integration between computer vision and natural language processing, has emerged as a key research direction in the field of artificial intelligence. This technology aims to achieve automatic understanding and language expression of video content, enabling computers to transform visual information in videos into textual form. This paper provides an initial analysis of the research trends in deep learning-based video captioning and categorizes them into four main groups: CNN-RNN-based Model, RNN-RNN-based Model, Multimodal-based Model, and Transformer-based Model, and explain the concept of each video captioning model. The features, pros and cons were discussed. This paper lists commonly used datasets and performance evaluation methods in the video captioning field. The dataset encompasses diverse domains and scenarios, offering extensive resources for the training and validation of video captioning models. The model performance evaluation method mentions major evaluation indicators and provides practical references for researchers to evaluate model performance from various angles. Finally, as future research tasks for video captioning, there are major challenges that need to be continuously improved, such as maintaining temporal consistency and accurate description of dynamic scenes, which increase the complexity in real-world applications, and new tasks that need to be studied are presented such as temporal relationship modeling and multimodal data integration.