{"title":"Design and Application of Tuned Mass Damper using Magneto Rheological Fluid for Vibration Control of Structure in Power Plant","authors":"Jun-Han Song, Hyeon-Seop Lee, Hong-Gi Lee, Jae-Ho Baek","doi":"10.7315/cde.2023.326","DOIUrl":"https://doi.org/10.7315/cde.2023.326","url":null,"abstract":"When several pulverizers operating simultaneously at the same rotational speed for coal pulverization in a thermal plant, workers inside the nearby control structure complained of discomfort due to the vibration. Through structure and transmission path vibration measurement the phenomenon of vibration amplification in the structure due to resonance and the concentration of vibration energy in the roof due to structural characteristics were identified. To reduce the vibration in the control room, the design of the main factors of the TMD(Tuned Mass Damper) was conducted. An analysis of the optimal mass, stiffness, and damping characteristics of the TMD was designed using a finite element analysis program ANSYS. MR(Magneto-Rheological) fluid was used for the damper of the TMD for the optimal vibration reduction effect considered to the site conditions. The optimal position of the TMD in the structure was selected, and the reduction effect was verified by conducting vibration monitoring before and after installing the vibration mitigation measures.","PeriodicalId":500791,"journal":{"name":"Korean Journal of Computational Design and Engineering","volume":"67 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136271527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of Real-Time Simulation Model for Determining the Drop Point from Unmanned Aerial Vehicles","authors":"Ho-Jin Hwang","doi":"10.7315/cde.2023.273","DOIUrl":"https://doi.org/10.7315/cde.2023.273","url":null,"abstract":"With the increasing importance of initial response in emergency maritime rescue systems, there has been a rise in applications involving aerial delivery or dropping of objects from unmanned vehicles. Training plays a vital role in supporting mission execution in military and emergency situations. However, real-world training encounters limitations in terms of cost and safety, making virtual training a viable alternative. This paper analyzes and proposes approaches for realtime simulation of dropping object from unmanned vehicles for educational training purposes. The educational training simulation models can be classified into three categories: physics-based simulation mathematical models, data-driven search models, and probability-based simulation estimation models. Physics-based models ensure accuracy, but real-time processing is challenging. Data-driven models, on the other hand, cannot adapt to new input conditions. Therefore, a probability-based simulation estimation model, considering uncertainties, is deemed suitable for educational training simulations. The probability-based model provides estimation outputs based on probability distributions, accommodating diverse variables. To implement a specific probability-based estimation model, diverse environmental input conditions should be utilized, and simulation results must be compared and validated against mathematical models. The model","PeriodicalId":500791,"journal":{"name":"Korean Journal of Computational Design and Engineering","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136271526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Study on the Criteria of Function Optimization with Smart Devices for Effective Management of Academy","authors":"Kunuk Park, Bi Sin, Sungmi Kim, Ho-Jin Hwang","doi":"10.7315/cde.2023.251","DOIUrl":"https://doi.org/10.7315/cde.2023.251","url":null,"abstract":"With the expansion of the private education market, the importance of an effective academy management system for handling data generated by academy has grown. Existing systems often impose user burdens due to a lack of consideration for device-specific characteristics. In this paper, we analyze the characteristics of four smart devices: desktops, kiosks, tablets, and mobile devices. Based on these analyzed characteristics, we propose optimization criteria, including easy input of data, easy view of data, portability of devices, limitation of functions, high capacity of data processing, and low capacity of data processing. Utilizing this classification, we form eight quadrants and implement tailored services within the actual academy management system to align with the specific characteristics of each smart device. This paper confirms the importance of interface design that considers user experience. The developed academy management system is expected to provide an efficient user interface, enhancing operational efficiency and usability. By addressing the unique characteristics of diverse smart devices, this study offers insights for improving user experience in academy management systems.","PeriodicalId":500791,"journal":{"name":"Korean Journal of Computational Design and Engineering","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136271529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"B-Rep Shape Simplification for Data Conversion between Ship CAD Model and VR Mesh Model","authors":"Jaehong Yoo, Jeongsam Yang","doi":"10.7315/cde.2023.260","DOIUrl":"https://doi.org/10.7315/cde.2023.260","url":null,"abstract":"Shipbuilders and suppliers, through their engineering activities, generate an extensive array of shape data for ship structures. However, visualizing the entire shape of a ship on a computer for design optimization or digital evaluation poses a practical challenge. Additionally, it becomes necessary to simplify the boundary representation (B-Rep) shape during data exchange between partners using different computer-aided design (CAD) systems and when creating lightweight shape contents for digital twin implementation. In this paper, we propose a shape simplification method for converting shapes between ship CAD model and virtual reality (VR) mesh model. During the process of reconstructing the ship CAD model into a B-Rep shape, topology decimation is performed to remove unnecessary elements. Furthermore, bounding boxes are created for the sub-primitives of the reconstructed B-Rep shape, and the level of detail for shape simplification is determined by calculating threshold values for these boxes. Sub-primitives with the applied level of detail can be dynamically removed from the assembly model. By utilizing this method, our shape simplification system, ShipCADOptimizer, allows users to review model simplification results in real-time through its simplification functionality. Users can simplify the model while preserving its characteristics by setting appropriate weights and thresholds based on the intended use.","PeriodicalId":500791,"journal":{"name":"Korean Journal of Computational Design and Engineering","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136271533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}