• Journal of the Korea Institute of Building Construction
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• v.14 no.2
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• pp.177-186
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• 2014

The gang-form widely used in apartment construction sites has advantages compared to scaffolding in preventing falling accidents. One problem, however, is that safety accidents associated with gang-form works repeatedly occur due to worker carelessness. In this study, hierarchical checking tables are provided to support safety management activities for the gang-form works at the sites. Through a survey of experts and analyses of case studies of construction accidents, 137 safety check items are classified by participant type based on a hierarchical safety check scheme. The applicability and effectiveness of the hierarchical checking tables was evaluated through interviews with experts. It was found that the hierarchical checking tables enabled each gang-form related participant to check his own safety management items, and provided a level-wise structure to site safety management systems.

• Journal of Power System Engineering
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• v.18 no.4
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• pp.91-96
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• 2014

The application of the recent model-based control schemes for robot manipulators require the solution of problems concerning various aspects, from the mechanical design to the necessity of determining a robot model suitable for control, and of experimentally testing the control performances. For one solution, integration of SolidWorks with Simscape for designing and controlling robot manipulators is presented in this paper. The integration provides a platform for rapid control prototyping of robot manipulators without the need for building real prototypes. Mechanical drawings of a robot are first created using Solidworks and imported into the Simscape, where a robot is represented by connected block diagrams based on the principle of physical modeling. Simulation examples for 7-DOF SAM ARM made by Berrett Technology Inc. are testified to show effectiveness of the presented platform.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.996-1001
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• 2005

Today, government is no longer considered the sole provider of public works or services. Public-Private Partnership (PPP) has been recognized as an important approach to solving problems for governments in providing public works and services. However, the joint ownership of public works/services complicates the administration of PPP projects. Particularly, the fact that government may rescue a distressed project and renegotiate with the developer causes serious problems in project procurement and management. This paper aims to study when and how government will rescue a distressed project and what impacts government's rescue behavior has on project procurement and contract management. A game-theory based model for government rescue will be developed. This pilot study, the author hopes, may provide theoretic foundations to practitioners/policy makers for prescribing creative PPP procurement and management policies and for examining the effectiveness of PPP policies.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.344-352
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• 2003

Sediment plumes arising from various coastal works can cause detrimental effects on the coastal ecosystem in various manners. Although the most active countermeasure against the plumes is to restrict the works to specified time periods known as environmental windows (Reine et al., 1998), silt screens have been widely used for reducing the spreading of suspended sediments (SS) generated by coastal works. (omitted)

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.1
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• pp.33-39
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• 2007

LonWorks over IP (LonWorks/IP) virtual device network (VDN) is an integrated form of LonWorks device network and IP data network. LonWorks/IP VDN can offer ubiquitous access to the information on the factory floor and make it possible for the predictive and preventive maintenance on the factory floor. Timely response is inevitable for predictive and preventive maintenance on the factory floor under the real-time distributed control. The network induced uncertain time delay deteriorates the performance and stability of the real-time distributed control system on LonWorks/IP virtual device network. Therefore, in order to guarantee the stability and to improve the performance of the networked distributed control system the time-varying uncertain time delay needs to be compensated for. In this paper, under the real-time distributed control on LonWorks/IP VDN with uncertain time delay, a control scheme based on disturbance observer and ZPETC(Zero Phase Error Tracking Controller) phase lag compensator is proposed and tested through computer simulation. The result of the proposed control is compared with that of internal model controller (IMC) based on Smith predictor and disturbance observer. It is shown that the proposed control scheme is disturbance and noise tolerant and can significantly improve the stability and the tracking performance of the periodic reference. Therefore, the proposed control scheme is well suited for the distributed servo control for predictive maintenance on LonWorks/IP-based virtual device network with time-varying delay.

• International Journal of Highway Engineering
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• v.14 no.4
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• pp.141-148
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• 2012

PURPOSES : This study demonstrates the need for the collection of road weather information in order to perform efficient snow removal works during the winter season. Snow removal operations are usually dependent upon weather information obtained from the Automatic Weather Station provided by the Korea Meteorological Administration. However, there are some difference between road weather and weather forecasts in their scope. This is because general weather forecasts are focused on macroscopic standpoints rather than microscopic perspectives. METHODS : In this study, the relationship between snow removal works and historical weather forecasts are properly analyzed to prove the importance of road weather information. We collected both weather data and snow removal works during winter season at "A" regional offices in Gangwon areas. RESULTS : Results showed that the validation of weather forecasts for snow removal works were depended on the height difference between AWS location and its neighboring roadway. CONCLUSIONS : Namely, it appears that road weather information should be collected where AWS location and its neighboring roadway have relatively big difference in their heights.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.1
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• pp.41-52
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• 2018

The purpose of this study is to examine the circumstances of repair works after enacting "Low for Conservation of Joseon Treasure, Historic Site, Scenic Beauty & Natural Monument (朝鮮寶物古跡名勝天然記念物保存令)". For this purpose, the official documents produced by the Government-general Museum of Joseon were analyzed. They included the contents of repair works of Hwaumsa Kakhwangjeon(華嚴寺 覺皇 殿). As a result, this study reveals that the repair work of Hwaumsa Kakhwangjeon had become a momentum of introducing specific guidelines such as "Guidelines for Architectural Treasure's Repair 寶物建造物修理施行準則", "Regulations for administration of Hwaumsa Kakhwangjeon's repair work 華嚴寺覺皇殿修理工事取扱手續)". The guidelines and regulations systematized the planning phase of the repair works and provided to organize the field office formed by experts. In spite of these positive changes, the repair works were controlled by the central government to the certain extent, and the Japanese repair techniques were mingled with traditional techniques recklessly.

• Journal of the Ergonomics Society of Korea
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• v.30 no.4
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• pp.481-489
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• 2011

Objective: The aim of this study was to develop an ergonomic checklist (AULA: Agricultural Upper-Limb Assessment) which can assess the risks of the work-related upper limb disorders of farming tasks in Korea. Background: There are few assessment tools that reflect the current condition of agricultural works as of now. Method: AULA was developed as following three stages. First of all, a physiological experiment was conducted with selected 14 upper limb postures which are frequently occurred in farming tasks and then, an ergonomic checklist was developed with determining risk levels of each body posture based on the experimental findings. Lastly, the ergonomic checklist was validated by comparing with the existing assessment tools. Results: When comparing the AULA which was developed in this study with the existing assessment tools, it was found that the AULA may get over limits of the existing ones which are sensitive to particular postures, but aren't sensitive to the rest of them. Conclusion: It is predicted that the developed upper limb posture assessment tool which gets over the existing tools' limits and is proper for domestic farm work conditions, will help to reduce musculoskeletal disorders caused by farm works, by assessing farm works more easily and objectively. Application: By further developing the theoretical groundwork on the induction of muscular skeletal system symptoms relating to agricultural works, it is expected to improve the level of preventing and managing such muscular skeletal system symptoms in the field of agricultural and farming works, which is relatively less advanced in terms of labor difficulties.

• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.148-158
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• 2006

Public construction companies have strictly followed a rule that they should not do the works using water such as concrete pouring for the structural frame for a certain period during the winter season. It is usually known that the designated non-working period during the winter causes increase of the project duration and the project cost escalation. The halted work also makes negative effects on national economy because it reduces worker's income. However, the situation would be a lot better if the work for the structural frame is allowed under some conditions. The structural framework done alone without being followed by finish works gives a lot of stresses on the finish works. In this sense, this study examines how the structural framework performed during the winter season affect on the critical path of the finish works. To accomplish the objective of this research, the subnet for the finish works as well as a master network are prepared along with critical paths for a virtual construction site. Using the prepared networks, simulations are carried out to see the effects described above. This study is expected to be used in estimating the construction duration of high-rise apartment housing when the site work for the structural frame should be performed during this period.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.273-275
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• 2009

In recent years, many home machines have been developed in order to design and control comfortable interior inside houses. For such task, important factors are temperature, natural and interior lights, and space and control of relative factors each other. This paper presents novel sensor module inside houses, which is designed based on these factors through the PMV (Predicted Mean Vote) standard using information about home state. Moreover, LonWorks based power line communication technique is utilized for control interior lights and air-conditioners by means of wireless remote controllers. This mechanism is systemically operated via intelligent control framework.