• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.6
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• pp.754-762
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• 2019

The transfer case for special truck are usually produced by only a few specialized companies. The special technical data are not unveiled. In order to complete the development successfully, it is necessary to carry out the compatibility tests such as the running test on the vehicle, which is the test condition of the military vehicle. In this research, transfer case the core-component of the '230 mm K-MLRS' has been developed with the reverse engineering and the prototype is developed through structural analysis. The transfer case developed through this research is currently used in the '230 mm K-MLRS'. The development process In this research are useful in the development of similar products.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.3
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• pp.36-42
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• 2022

Whereas the necessity for recycling and reuse is being emphasized owing to the depletion of resources and waste disposal problems caused by the continuous development of the industry, the importance of remanufacturing has been highlighted recently. Re-manufacturing involves a series of processes in which failed disposal or aging goods are recovered to a state similar to that of a new product. In this regard, machine tools, which are large structures, can achieve the effect of remanufacturing. Among the various elements constituting the machine tool, the main spindle portion that affects the processing precision is critical. Therefore, this study is conducted to derive improvement measures for the main axis of an old Miller planner via reverse engineering and central composite design, which is one of the core processes of remanufacturing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.400-406
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• 2017

The model used in this study was reversed to analyze the cause of excessive damage that occurred inside the rotating system and pipe system of a centrifugal-type seawater pump on a ship. For this purpose, internal flow analysis on a cooling seawater pump was performed using CFD. As a result, the shape and boundary conditions of the target pump were set by reverse engineering, and pump efficiency at a design operating point of $125m^3/h$ was calculated as 85.3 % with a head of 32.0 m. The maximum efficiency point of the target pump was estimated to be 86.2 % at $150m^3/h$, but this differed from the actual operating point. At $112.5m^3/h$, which was the lowest flow point, flow was unstable due to the characteristics of the low flow point and analysis convergence was not good. The purpose of this study was to clarify the cause of ongoing cavitation in seawater pumps and piping systems in operation. Future research will be needed to clarify causes for pipe systems in the future by performing calculations for the total piping system of an inlet and outlet, in addition to measuring the flow rate of each branch pipe.

• Explosives and Blasting
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• v.40 no.4
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• pp.15-26
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• 2022

With the recent increase in old and dangerous buildings, the demand for technology in the field of structure demolition is rapidly increasing. In particular, in the case of structures with severe deformation of damage, there is a risk of deterioration in stability and disaster due to changes in the load distribution characteristics in the structure, so rapid structure demolition technology that can be efficiently dismantled in a short period of time is drawing attention. However, structural deformation such as unauthorized extension or illegal remodeling occurs frequently in many old structures, which is not reflected in structural information such as building drawings, and acts as an obstacle in the demolition design process. In this study, as an effective way to overcome the discrepancy between the structural information of old structures and the actual structure, access to actual structures through 3D modeling was considered. 3D point cloud data inside and outside the building were obtained through LiDAR and drone photography for buildings scheduled to be blasting demolition, and precision matching between the two spatial data groups was performed using an open-source based spatial information construction system. The 3D structure model was completed by importing point cloud data matched with 3D modeling software to create structural drawings for each layer and forming each member along the structure slab, pillar, beam, and ceiling boundary. In addition, the modeling technique proposed in this study was verified by comparing it with the actual measurement value for selected structure member.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.06a
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• pp.21-27
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• 2001

• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.126-130
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• 1997

A new and efficient method is presented for design optimization, which is based on a computational fluid dynamics (CFD). The method is applied to design an airfoil configuration. The Navier-Stokes equations are solved for the viscous analysis of the flow, which provides the object function. The CFD analysis is then coupled with the optimization procedure that used a conjugate gradient method. During the one-dimensional search of the optimization procedure, an approximate flow analysis based on a first-order Taylor series expansion is used to reduce the computational cost, (This study is supported by Korean Ministry of Education through Research Fund)

• Defense and Technology
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• no.2 s.300
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• pp.84-95
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• 2004

전 세계적으로 43개국이 500여척의 잠수함을 보유하고 있으나 실제 잠수함을 독자설계할 수 있는 국가는 10개국에 불과하다. 이들의 기본바탕은 연관산업의 기수리과 더불어 실제의 전쟁경험과 많은 시행착오를 거쳐오면서 약 100여 년간 축적된 잠수함 건조 기술이 있기 때문으로 판단된다. 세계 1위를 자랑하는 우리 나라의 조선산업도 초기에는 해외에서 설계도면을 가져와 조립하는 과정을 거쳐 생산기술을 확보한 후 모방설계, 역설계를 통하여 순수 독자설계능력을 확보하였음은 주지의 사실이다.

• Journal of Advanced Navigation Technology
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• v.24 no.4
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• pp.314-321
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• 2020

Logic automated stimulus and response (LASAR) software is an automatic test program development tool for logic function test and fault detection of avionics components digital circuit cards. LASAR software needs to the information for the logic circuit function and input and output of the device. If there is no component information, normal component modeling is impossible. In this paper, component modeling is carried out through reverse design of programmable logic device (PLD) device without element information. The developed LASAR program identified failure detection rates through fault simulation results and single-seated fault insertion methods. Fault detection rates have risen by 3% to 91% for existing limited modeling and 94% for modeling through the reverse design. Also, the 22 case of stuck fault with the I/O pin of EP310 PLD were detected 100% to confirm the good performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.107-114
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• 2020

Technologies related scan-to-BIM for BIM-based reverse engineering techniques are beginning to be actively introduced in the A.E.C. industry, and the scalability of the technology is growing considerably. This study uses patent analysis based on objective data to find the right direction for Korean Scan-to-BIM technology by identifying the trends in Korea, the United States, Europe, and Japan. This was done using the WIPSON patent search system to find previous research on patent analysis related to building technology, theoretical consideration of scan-to-BIM technology, and published patents. We collected information, verified the process, and extracted valid patents. We used the effective patent data to analyze the annual trend of patent applications, national trends, and technological trends through the International Patent Classification (IPC) code, the types of the top 20 major applicants, and family patent trends.

• Journal of Advanced Navigation Technology
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• v.25 no.1
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• pp.29-39
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• 2021

As a means of solving traffic congestion in the downtown of large city, the interest in urban air mobility (UAM) using electric vertical take-off landing personal aerial vehicle (eVTOL PAV) is increasing. eVTOL configurations that will be used for UAM are classified by lift-and-cruise, tilt rotors, tilt-wings, tilted-ducted fans, multicopters, depending on propulsion types. This study tries to perform preliminary conceptual design for a given mission profile using reverse engineering techniques by taking the multicopter type Airbus's CityAirbus as a basic model. Wetted area, lift to drag ratio, drag coefficients were calculated using the OpenVSP which is an aerodynamic analysis software. The power required for each mission section of CityAirbus were calculated, and the corresponding battery and motor were selected. Also, total weight was predicted by estimating component weights of eVTOL.