• Journal of the Korean Wood Science and Technology
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• 제33권2호통권130호
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• pp.8-16
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• 2005

In an effort to encourage the development of value added engineered applications for small diameter round timber, research is being conducted to develop and verify design guidelines for connections with specific application to round timbers. The objective of this research is to provide potential users with a number of viable connection options applicable in the fabrication of engineered, round wood structural components and systems. Target uses include trusses, built up flange beams and space frames. This paper presents information on a mortised steel plate connection fabricated using powder driven nails in 6 cm diameter Japanese Larch. The design load for PDN connections are around 1.3 kN per nail with strip and 0.8 kN per nail without stripe. The design model for PDN connectors could be chosen by the number of nails. If the number of nails are more than the critical number between nail bearing and wood failure, the wood failure model could be the way to design the structure safely. The wood failure model needs to be studied more but the model could be the tensile and cleavage mixed failure model.

• International Journal of Precision Engineering and Manufacturing
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• 제4권3호
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• pp.12-19
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• 2003

This paper describes the design of a robot's hand with two fingers for stably grasping an unknown object, and the development of a 3-axis force sensor for which is necessary to constructing the robot's fingers. In order to safely grasp an unknown object using the robot's fingers, they should measure the forces in the gripping and in the gravity directions, and control the measured forces. The 3-axis force sensor should be used for accurately measuring the weight of an unknown object in the gravity direction. Thus, in this paper, the robot's hand with two fingers for stably grasping an unknown object is designed, and the 3-axis force sensor is newly modeled and fabricated using several parallel-plate beams.

• Steel and Composite Structures
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• 제35권3호
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• pp.327-341
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• 2020

The use of high-strength steel and concrete in the construction industry has been gaining increasing attention over the past few decades. With it comes the need to utilise high-strength structural bolts to ensure the design load to be transferred safely through joint regions, where the space is limited due to the reduced structural dimensions. However, research on the behaviour of high-strength structural bolts under various loading combinations is still insufficient. Most of the current design specifications concerning high-strength structural bolts were established based on a very limited set of experimental results. Moreover, as experimental programs normally include limited design parameters for investigation, finite element analysis has become one of the effective methods to assist the understanding of the behaviour of structural components. An accurate and simple full-range stress-strain model for high-strength structural bolts under different loading combinations was therefore developed, where the effects of bolt fracture was included. The ultimate strength capacities of various structural bolts obtained from the present experimental program were compared with the existing design provisions. Furthermore, design recommendations concerning the pure shear and tension, as well as combined shear and tension resistance of Grade 10.9 high-strength structural bolts were provided.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.162-167
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• 2003

In this paper, a novel feasible real-time system was researched for a differential driven wheeled autonomous mobile robot so that the mobile robot can move in a smooth, safe and elegant way. Least Square Minimum Path Planning was well used for the system to generate a smooth executable path for the mobile robot, and the point-to-point tracking algorithm was presented as well as its application in arbitrary path tracking. In order to make sure the robot can run elegantly and safely, trapezoidal speed was integrated into the point-to-point path tracking algorithm. The application to guest following for the autonomous mobile robot shows its wide application of the algorithm. The novel design was successfully proved to be feasible by our experiments on our mobile robot Interactive Robot Usher (IRU) in National University of Singapore.

• Journal of Advanced Research in Ocean Engineering
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• 제3권3호
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• pp.112-124
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• 2017

As an LNG carrier preserves and transports liquefied natural gas under minus $163^{\circ}C$, the cargo tank has to have sufficient hull strength against not only the wave loads but also against loads caused by loading and unloading and thermal expansion to keep the LNG safely. The main insulation types for a CCS are No.96 and Mark III from GTT for the membrane LNG carrier. Particularly, the invar membrane plate in No.96 is very thin and its connections could experience high local stresses owing to such dynamic loads. Therefore, it should be verified whether those connections have sufficient fatigue lives for the purpose of operation and maintenance. This research aims at performing fatigue analysis with 0.1 fatigue damage criteria for 40 years of design life to support new membrane CCS development using proper S-N curves and the associated finite element modeling technique for each connection and then propose a reasonable design methodology.

• Nuclear Engineering and Technology
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• 제53권7호
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• pp.2268-2276
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• 2021

Spent nuclear fuel, which can degrade during long-term storage, must be transported intact in normal transport conditions. In this regard, many studies, including those involving Multi-Modal Transportation Test (MMTT) campaigns, have been conducted. In order to transport the spent fuel safely, a tie-down structure for supporting and transporting a cask containing the spent fuel is essential. To ensure its structural integrity, a method for finding an optimum conceptual design for the tie-down structure is presented. An optimized transportation test model of a tie-down structure for the KORAD-21 metal cask is derived based on the proposed optimization approach, and the transportation test model is manufactured by redesigning the optimized model to enable its producibility. The topology optimization approach presented in this paper can be used to obtain optimum conceptual designs of tie-down structures developed in the future.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 1999년도 추계학술대회
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• pp.381-389
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• 1999

One of the objectives of any task design is to provide a safe and helpful workplace for the employees. The safety and health module may include means for confronting the design with safety and health regulations and standards as well as tools for obstacles and collisions detection (such as error models and simulators). Virtual Reality is a leading edge technology which has only very recently become available on platforms and at prices accessible to the majority of simulation engineers. The design of an automated manufacturing system is a complicated, multidisciplinary task that requires involvement of several specialists. In this paper, a design procedure that facilitates the safety and ergonomic considerations of an automated manufacturing system are described. The procedure consists of the following major steps: Data collection and analysis of the data, creation of a three-dimensional simulation model of the work environment, simulation for safety analysis and risk assessment, development of safety solutions, selection of the preferred solutions, implementation of the selected solutions, reporting, and training When improving the safety of an existing system the three-dimensional simulation model helps the designer to perceive the work from operators point of view objectively and safely without the exposure to hazards of the actual system.

• 한국기계가공학회지
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• 제18권4호
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• pp.48-55
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• 2019

With recent rapid increases in the power generation capacity of offshore wind power generators, reliable structural analysis of the large-scale infrastructure needed to install wind power generators at sea is required. Therefore, technology for heavy marine equipment such as barges and excavation equipment is needed. Under submarine conditions, rock drilling technology to install the substructure for offshore wind pile excavation is a very important factor in supporting a wind farm safely under dynamic loads over periods of at least 20 years. After investigating the marine environment and on-site ground excavation for the Saemangeum offshore wind farm, in this study we suggest.

• 한국도로학회논문집
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• 제17권6호
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• pp.33-36
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• 2015

PURPOSES : It is desirable for buses to be parallel to the face of the bus shelter at a bus stop. In this way, passengers can safely use the buses without moving into the vehicle area. The study was a review of the current bus bay geometric guidelines, to determine whether they lead buses to stop parallel to the face of the bus shelter by analyzing vehicle trajectory. METHODS : A commercial software program for vehicle trajectory analysis was used under our assumptions about bus dimensions and geometric values. The final position of the bus was analyzed for multiple trajectory simulations, reflecting various geometric alternatives. RESULTS : Within the scope of the study, we concluded that the current design guidelines need to be revised by the design values suggested by the study. CONCLUSIONS : The results of the study suggested alternative design values for bus bay geometry, based on the assumption that buses should be parallel to the face of the bus shelter in order to prevent passengers from moving into the vehicle area.

• Journal of Biosystems Engineering
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• 제13권4호
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• pp.46-55
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• 1988

The objective of this study was to develop a computer measurement and control system which enable it possible to manage the natural air rough rice drying and storage properly and safely. The following contents of work were taken in this study in order to fulfill the above goal: 1) Design and construction of measurement system which can measure the rough rice drying conditions automatically and transfer them to computer system for data processing. 2) Development of a management software which can determine the need of fan operation by the analysis of drying and/or storage conditions. 3) Design and construction of a control system which deliver the computer decision of fan operation and make it on and off. 4) Technical and economical analysis of the computer measurement and control system development by the comparison experiments of the computer management and of the manual.