• 한국생산제조학회지
• /
• 제7권6호
• /
• pp.141-148
• /
• 1998

A loader is construction & road or agricultural machinery for lifting, moving, and mixing. This study deals with the agricultural mini loader for stock raising farming. The performance of the machine is established by pulling power, working lifting capacity, and minimum circling radius, etc. Also, driving easiness and endurance are very important in manufacturing. Thus, this study has developed the loader with the 4-wheel driving equipment by gear transmission, the 4-wheel steering equipment by power handle steering type, and the equipment making four wheels touch simultaneously on the rugged ground. The developed loader having these functions was very fit in a small cattle shed or a rugged ground. This study is divided into two parts; (I) development of 4WS transmission and (II) construction of the loader by 4WS system and other equipments.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제10권1호
• /
• pp.95-102
• /
• 2018

This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes are well-coordinated to add up the lift capabilities of both cranes without any loss such that virtually a single crane is lifting, maneuvering and unloading. Two main constraints for the dual lifting are as follows: First, two barges of floating cranes should be constrained as a rigid body not to cause a relative motion between two barges and main hooks of the two cranes should be controlled as main hooks of a single crane. In order words, it is necessary to develop the cooperative control of two floating cranes in order to sustain a center of gravity of the module and minimize the tilting angle during the lifting and unloading by the two floating cranes. Two floating cranes are handled as a master-slave system. The master crane is able to gather information about all working conditions and make a decision to control the individual hook speed, which communicates the slave crane by TCP/IP. The developed control system has been embedded in the real floating crane systems and the dual lifting has been demonstrated five times at SHI shipyard in 2015. The moving angles of the lifting module are analyzed and verified to be suitable for hoisting control. It is verified that the dual lifting can be applied for many heavier and wider blocks and modules to shorten the construction time of ships and off-shore platforms.

• 한국재난정보학회 논문집
• /
• 제13권3호
• /
• pp.358-365
• /
• 2017

전세계적으로 재난에 의한 피해가 급증하면서 인명피해를 줄이기 위한 장비에 대한 기술 개발이 필요한 실정이다. 이에 소방안전 및 119구조 구급기술연구개발사업의 지원으로 "인명구조용 소방대원 근력지원장치 개발(2015 ~ 2018)" 과제를 통하여 재난환경 및 재난 대응 시나리오를 고려한 리프팅 성능(양중하중 100 kg 이상, 양중높이 1 m 이상, 양중거리 60 cm 이상, 양중속도 0.2 m/s 이상)을 만족하는 장비를 개발 중에 있다. 본 연구는 장치의 유용성을 판단하기 위해 양중성능 및 내환경 시험법을 제안하였고, 양중성능시험의 동역학 해석을 통해 근력지원장치의 상세사양을 분석 및 검증하였다. 본 연구를 통하여 제안한 시험 방법은 근력지원장치의 안정적인 성능 구현여부를 평가하는데 실용적으로 적용할 수 있을 것으로 판단된다.

• 한국건축시공학회지
• /
• 제16권2호
• /
• pp.151-159
• /
• 2016

건설프로젝트에서 요구되는 중요한 장비 중 하나는 타워크레인 이다. 특히, 대부분의 고층건물 공사에서는 자재들의 이동작업들을 수행하기 위해 타워크레인이 더욱 요구되어진다. 따라서 타워크레인의 양중계획은 공사기간과 비용의 측면에서도 중요하다 할 수 있다. 하지만, 건설현장 대부분의 양중계획은 여전히 합리적인 작업의 분석없이 현장 관리자들의 경험과 직관에 의존하여 행해지고 있다. Dependency structure matrix (DSM)는 CPM과 Pert 같은 기존의 툴과는 다르게 작업 활동 순서 계획과 정보관리를 하는데 있어서 유용한 툴이다. 본 연구는 타워크레인의 양중 관리를 향상시키기 위하여 실제 건설 현장의 Case study를 통해 타워크레인 양중관리의 새로운 틀을 DSM을 이용하여 제시 할 것이다. DSM을 이용한 T/C의 양중계획의 Case study를 통해 나타난 결과는 기준층 양중 계획에 있어서 T/C의 양중계획을 최적화 시키는데 매우 유용하다는 결론을 보여주었다.

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.1047-1052
• /
• 2009

As buildings nowadays become taller in height and larger in size the safety review of lifting plan takes larger portion in construction project management. However, the cost and safety in lifting plan have a contradictory effect on each other. Therefore, an optimization algorithm needs devising as a solution of the contradictory problem. In many cases at construction sites, selections and stability review of tower cranes are assigned to equipment suppliers or field managers, which cause the problems in safety and cost of the projects. To improve the part of the current situation, a study on the optimization algorithm for designing the foundation of tower cranes is conducted in this study, which can be utilized by equipment suppliers or field managers to check the stability of tower cranes easily and promptly without substantial knowledge.

• 드라이브 ㆍ 컨트롤
• /
• 제17권1호
• /
• pp.81-87
• /
• 2020

• 대한인간공학회지
• /
• 제36권4호
• /
• pp.325-341
• /
• 2017

Objective: The purpose of this study is to suggest the guidelines of operation phases to minimize injuries and musculoskeletal disorders in manual material handling (MMH) tasks through literature reviews. The guidelines are presented as the preparing phase, lifting phase, carrying phase, and lowering phase. Also, we summarized the non-numerical general guidelines for MMH tasks. Background: Manual material handling is still a main cause to musculoskeletal disorders. Method: Procedures of a literature review are classified into database selection, keyword search, title review, abstract review related to literature selection, guideline review and arrangement. A total 48 papers and books were analyzed in detail by title and abstract reviews. Results: In the preparing phase, we suggested the basic conditions in MMH, preparing procedure, clothing and protective equipment, and education. In the lifting and carrying phases, we recommended maximal acceptable weight by frequency and body posture. In the lowering phase, we suggested the lowest weight and safety body postures. Finally, we recommended general guidelines and guideline items for MMH. General guidelines are presented to suggest worker selection, technical education, and work design parts. Conclusion: We suggested the guidelines on the four operation phases of MMH tasks such as preparing, lifting, carrying, and lowering phases. Application: The findings of this study can be utilized as guidelines for proactive recommendations according to workers in MMH tasks.

• 한국안전학회지
• /
• 제38권4호
• /
• pp.60-67
• /
• 2023

Various lifting slings are used in domestic industrial sites depending on the purpose, form, and environment. Each sling has its characteristics, and safe lifting work is possible when its performance meets the regulations. Therefore, this study analyzed domestic and foreign regulations and guidelines related to chain slings. It identified significant problems by analyzing the chain-sling-related disaster cases. The current status of chain slings used by various industries and the ways to improve chain sling safety were studied. The major chain sling issues were: 1) employing improper components to chains, 2) having different safety coefficients between the regulation and industrial standards, and 3) using chains unsuitable for lifting purposes. Based on these issues, the following measures were proposed to improve chain sling work safety: 1) revise the safety coefficient requirements under the Regulations on Occupational Safety and Health Standards, 2) disseminate specialized sling courses, and 3) strengthen on-site chain slings-related training. In the future, this study is expected to minimize chain use mistakes by unifying the safety coefficient related to chain slings and recognizing the importance of correctly selecting components employed in the chain.

• 국제초고층학회논문집
• /
• 제11권2호
• /
• pp.103-114
• /
• 2022

Tower crane is of great importance in the construction of high rise buildings. A self-lifting & slewing multi-cranes platform (referred to as crane slewing platform) was developed to optimize the configuration of tower cranes, as well as solve the problems of cooperative operation conflict between multiple cranes and other construction equipment and their respective climbing and occupying of construction period. The design and test of the slewing platform was introduced. By applying the slewing platform in the construction of Chengdu Greenland Center super high rise building project, some key technologies such as the configuration of cranes, the installation, construction and lifting of the slewing platform are implemented and validated. Up to now, the slewing platform has been safely lifted up 98 times in Chengdu Greenland Center project construction, and achieved good social and economic benefits.

• 한국건설관리학회논문집
• /
• 제9권3호
• /
• pp.185-193
• /
• 2008

점차 대형화, 고층화되고 있는 공동주택공사에서 작업효율성을 향상시키고자 양중작업의 최적화를 위한 리프트 선정방식의 합리적 절차와 기준이 요구되고 있다. 따라서, 작업효율성 및 경제적 측면에서의 분석을 통하여 양중자재의 종류 및 규격, 건축물의 높이, 공사기간에 따른 건설용 리프트의 합리적 선정 및 운영을 위한 기준을 제시할 필요가 있다. 본 연구의 목적은 고층화 복잡화되고 있는 공동주택건설 현장여건에 따른 효율적 양중계획 및 관리를 위하여 대표적인 양중장비인 저속형과 중속형 리프트의 작업효율성과 경제성의 비교 분석을 통하여 최적의 선정을 위한 기초적 자료를 제시하는 것이다. 본 연구의 주요 결과는 40층 기준으로 중속형 리프트가 저속형에 비해 약 43%의 작업효율이 높은 것으로 분석되었다. 본 연구의 결과는 향후 공사의 용도, 규모, 형태, 조건 등에 알맞은 건설용 리프트 선정 기준/지침/규정을 마련하는 연구의 기초자료로 활용될 것으로 기대된다.