• Title/Summary/Keyword: boom

Search Result 631, Processing Time 0.042 seconds

A Study on the Body Welding Operation Scheduling Considering the Assembly Line's Input Sequence in Construction Equipment Manufacturing (건설기계 조립 라인 투입 순서를 고려한 제관 공정 생산 스케줄링에 관한 연구)

  • Kim, Ki-Dong;Choi, Ho-Sik
    • Journal of Industrial Technology
    • /
    • v.27 no.A
    • /
    • pp.69-76
    • /
    • 2007
  • The body of an excavator, one sort of the construction equipment, consists of mainframe part, track frame part, boom part and arm part. The all parts are manufactured in the body welding operation. The scheduling in the body welding operation of a construction equipment manufacturing is to take all the various constraints into consideration. The offset time, due date, daily capacity of operations, daily jig's capacity, precedence relation, outsourcing, alternative resource and all of the shop floor environment should be considered. An APS(Advanced Planning & Scheduling) system is a proper and efficient system in such circumstance. In this paper, we present an APS system, the optimal scheduling system for the construction equipment manufacturing specifically for the body welding operation, using ILOG Solver/Scheduler. ILOG Solver/Scheduler is a general purposed commercial software which supports to find a feasible or optimal solution using object oriented technique and constraints satisfaction programming, given constraints and objectives.

  • PDF

Financial Innovation and Investor Wealth: A Study of the Poison Put in Convertible Bonds

  • Nanda, Vikram;Yun, Young-Keol
    • The Korean Journal of Financial Studies
    • /
    • v.3 no.1
    • /
    • pp.267-299
    • /
    • 1996
  • The takeover boom of the 1980s was accompanied by a series of innovations in debt contracts, including the poison put that allows bonds to be redeemed in the event of a corporate control change. The poison put was included in a large majority of convertible debt offerings, shortly after the first issues with such provisions. We attempt to understand the factors that contributed to the widespread adoption of this innovation in convertible bonds and the consequences for shareholder wealth. Our, findings suggest that by reducing the potential for bondholder-shareholder conflicts and by conveying positive information about future takeover prospect'5, poison puts result in significant benefits to issuing firm shareholders, particularly if the firm is under takeover speculation. There are, however, no benefits when a firm has adopted anti-takeover measures prior to the offering. There is weaker evidence that existing bondholders do worse when poison puts are present.

  • PDF

Thermoelastic Behaviors of Fabric Membrane Structures

  • Roh, Jin-Ho;Lee, Han-Geol;Lee, In
    • Advanced Composite Materials
    • /
    • v.17 no.4
    • /
    • pp.319-332
    • /
    • 2008
  • The thermoelastic behaviors of an inflatable fabric membrane structure for use in a stratospheric airship envelope are experimentally and numerically investigated. Mechanical tensile properties of the membrane material at room, high, and low temperatures are measured using an $Instron^{(R)}$ universal testing machine and an $Instron^{(R)}$ thermal chamber. To characterize the nonlinear behavior of the inflated membrane structure due to wrinkling, the bending behavior of an inflated cylindrical boom made of a fabric membrane is observed at various pressure levels. Moreover, the envelope of a stratospheric airship is numerically modeled based on the thermoelastic properties of the fabric membrane obtained from experimental data, and the wrinkled deformed shape induced by a thermal load is analyzed.

Wind Tunnel Test to Enhance Aerodynamic Characteristics of Forward Swept Wing Airplane (전진익형 항공기 공력특성 증진을 위한 풍동시험)

  • Chung, Jin-Deog;Lee, Jang-Yeon;Sung, Bong-Zoo;Lee, Jong-Won
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.28 no.7
    • /
    • pp.800-808
    • /
    • 2004
  • Wind tunnel test of an airplane model with forward swept wing was done in KARI LSWT to evaluate and measure the aerodynamic characteristics of initially designed configuration. Since the given wing planform did not fully satisfy the design requirements, local flow control devices such as vortilon, vortex generator and flow fence were used to delay separation and to enhance aerodynamic characteristics. Also decision making processes of design parameters such as vertical tail boom length, the location, size and the incidence angle of horizontal tail were discussed. The general aerodynamic characteristics of forward swept wing for various control surface deflection conditions of flap, aileron and elevator were also given.

A Case Study of the Design of Robot Welding Station in an Excavator Factory Using 3D Simulation (굴삭기공장에서 로봇을 이용한 용접공정의 3D 시뮬레이션 사례 연구)

  • Moon, Dug-Hee;Cho, Hyun-Il;Baek, Seung-Geun
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2005.11a
    • /
    • pp.113-121
    • /
    • 2005
  • Virtual Manufacturing is a powerful methodology for developing a new product, new equipment and new production system. It enables us to check the errors in design before production. This paper deals with a case study of virtual manufacturing in an excavator factory. Boom and rotating table of upper body are selected for application. 3D models of parts and fixtures are developed with CATIA and 3D simulation models are developed with IGRIP. These models are used for the design of fixture to verify the motion of the equipment. As a result, the manual welding systems are replaced by automatic systems and many design errors are corrected in the design phase, which enables us to reduce the developing cost and time.

  • PDF

Feasibility and Validity of u-4PL(Fourth Party Logistics) System with RFID (RFID를 적용한 u-4PL 시스템 개발에 관한 연구)

  • Na, Hyeong-Seok;Li, Zhong Shi;Lee, Chang-Ho
    • Journal of the Korea Safety Management & Science
    • /
    • v.9 no.5
    • /
    • pp.87-95
    • /
    • 2007
  • Logistics creates a boom in accordance with the recent new technique's development along with the recent RFID/USN of ubiquitous computing technique. The wave of 4PL(Fourth Party Logistics) that added the strategic consulting based on new IT techniques to logistics outsourcing through existing 3PL service with is a great issue. Moreover, the customer enterprises which contained manufacturers and distributors need the one stop service, therefore a method for effectively dealing with global logistics' environment changes is needed. Above all, a development of the 4PL system with RFID is very urgent. We developed the RFID u-4PL system progressed more than the present system, in which we applied many international standards. Finally, we constructed the web service based on Web 2.0 because of important condition of 4PL.

Deep Learning Research Trend Analysis using Text Mining

  • Lee, Jee Young
    • International Journal of Advanced Culture Technology
    • /
    • v.7 no.4
    • /
    • pp.295-301
    • /
    • 2019
  • Since the third artificial intelligence boom was triggered by deep learning, it has been 10 years. It is time to analyze and discuss the research trends of deep learning for the stable development of AI. In this regard, this study systematically analyzes the trends of research on deep learning over the past 10 years. We collected research literature on deep learning and performed LDA based topic modeling analysis. We analyzed trends by topic over 10 years. We have also identified differences among the major research countries, China, the United States, South Korea, and United Kingdom. The results of this study will provide insights into research direction on deep learning in the future, and provide implications for the stable development strategy of deep learning.

Placemaking in the High-Rise City: Architectural and Urban Design Analyses

  • Al-Kodmany, Kheir
    • International Journal of High-Rise Buildings
    • /
    • v.2 no.2
    • /
    • pp.153-169
    • /
    • 2013
  • The past decade has witnessed an unprecedented boom in tall and supertall building construction worldwide (Wood, 2011). Because of their massive bulk and soaring height, tall buildings often create serious placemaking problems. Employing extensive photographs and sketches, this paper examines architectural and urban design strategies that improve placemaking with tall buildings. The paper embraces a comprehensive approach that considers the relationship of tall buildings to their surroundings at the macro and micro scales. It also considers non-physical factors that tall buildings need to address, such as the social life the building creates. It is hoped that the placemaking factors discussed in this article will provide the required groundwork for future research that explores regulations and codes that foster placemaking with tall buildings.

A Bayesian Analysis of Structural Changes in Aggregate Demand and Supply of Korean Economy (한국경제의 총수요와 총공급에서의 베이지안 구조변화 분석)

  • Jun, Duk-Bin;Park, Dae-Keun
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.24 no.4
    • /
    • pp.475-483
    • /
    • 1998
  • Structural changes in an economy system bring about serious problems in establishing economic policies. The boom of middle-east export, the oil shock, and the recent dollar crisis in Korean economy are such examples. Hence, it is necessary to identify and estimate those structural changes. This study focuses on an output and price and analyzes structural changes in aggregate demand and supply. The aggregate demand and supply structures are described by conventional dynamic simultaneous equations model, where each structural change is represented by dummy variables and estimated by the proposed Bayesian method. By applying this model to Korean output and price, structural changes in the aggregate demand and supply are analyzed.

  • PDF

Automation of Tower Cranes based on Optimal Control Method (최적 제어법에 의한 타워크레인의 자동화에 관한 연구)

  • Lee, Jin-Woo;Kim, Sang-Bong
    • Journal of the Korean Society of Safety
    • /
    • v.8 no.4
    • /
    • pp.213-222
    • /
    • 1993
  • This paper is concerned with automation of tower cranes in view of the robust control of tower crane during take-off, load hoisting, load lowering and landing. The model equation of the tower crane is induced by using Lagrange's equation and it is linearized at equillibrium point. The control is realized by adopting the optimal regulator method. The effectiveness is proved through the experimental results for the oscillation control of cargo rope and the position controls of trolley and boom by the implementation of digital control using 16 bits microcomputer for the designed optimal control law.

  • PDF