• Title/Summary/Keyword: Korean Construction Machinery

Search Result 525, Processing Time 0.024 seconds

A Study on Developing the Classification Scheme of Library Goods (도서관용품 분류체계 개발에 관한 연구)

  • Noh, Young-Hee;Ahn, In-Ja;Park, Mi-Young;Joung, Hyun-Tae
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.45 no.1
    • /
    • pp.125-147
    • /
    • 2011
  • Recently, with a high demand for the construction and remodeling of libraries, and the rapid increase in the number of libraries during the last two years, the concern and need for library goods is also increasing sharply. The purpose of this study is to develop a new classification scheme of library goods by clarifying the terminology which could provide an accurate information on library goods and allow for their smooth circulation. In this study, library goods are defined as all kinds of products required for effectively collecting, organizing and providing services with library materials, and classified into library equipments and library supplies. The term, library equipment is principally used for those things that do not wear out within a certain time period, such as furniture and machinery. Library supplies refer to those things that are expendable. As the terminology is clarified, the classification scheme can be further refined. Library equipment, for example, can be classified as furniture, library system solutions, and computers and multi-media tools. Library supplies can be classified into library organization and repair supplies, sign systems, and miscellaneous articles. Finally, six major categories which include 117 different items are presented.

Fire Examples Study of Intake and Exhaust System, Alternator Tuning and Inflow of Inflammables on Exhaust Part in a Car (자동차 흡배기장치, 발전기 튜닝 및 배기측 인화성 물질 유입에 관련된 화재사례 연구)

  • Lee, Il Kwon;Kook, Chang Ho;Suh, Moon Won;You, Chang Bae;Youm, Kwang Wook;Lim, Chun Moo;Jung, Dong Hwa
    • Journal of the Korean Institute of Gas
    • /
    • v.18 no.5
    • /
    • pp.47-51
    • /
    • 2014
  • This paper is to analyze and study the fire examples in respect of intake and exhaust, alternator tuning and inflow of inflammables on exhaust part in a car. In the first example, the driver diverted the intake and exhaust system for tuning of a car. Stopping a car to rest for moment, the flammable styrofoam scrap go into exhaust pipe that installed with exhaust manifold newly. It certified the fact that catched fire gradually, furthermore enlarged the fire by leaking fuel. In the second example, the driver enlarged the generator performance to divert the audio system in side room., it knew the fact that the electric wiring connected with generator gave the cause of outbreak a fire by overheating. In the third example, the serviceman replaced the engine oil using funnel-shaped, he put the a bottle of plastic pat onto engine cover carelessly. Consequentially, it found the fire occurrence in the engine room. Therefore, the driver never divert the intake and exhaust and generator construction of a car abnormally. Also, repairing and inspecting a car, the serviceman have a care to not occur the fire by inflammables.

The Status, Problems, and the Direction of Development of Land Use in Reclaimed Land - Survey for Local Governments and the KRC Branch in Chungnam, Jeonbuk, and Jeonnam Province - (간척지의 토지이용 현상과 문제점 파악 및 발전방향 - 충남, 전북, 전남 지역 지자체 및 한국농어촌공사 지사 대상 설문조사 -)

  • Son, Jae-Gwon;Jeong, Chan-Hee;Lee, Dong-Ho;Go, Seung-Hwan;Song, Jae-Do;Lee, Gi-Sung;Park, Jong-Hwa
    • Journal of Korean Society of Rural Planning
    • /
    • v.26 no.3
    • /
    • pp.67-77
    • /
    • 2020
  • The purpose of this study was to determine the problems of reclamation sites and the prospects of farming in reclamation areas seen by local governments and the KRC branches in Chungnam, Jeonbuk, and Jeonnam provinces. A mail survey method was used. The survey items were set for 15 items regarding the reclamation site situation, problems, and prospects. Seventy-five copies of the questionnaire were distributed to the local government, and 90 copies were sent to the KRC 165 copies in total. In response to the questionnaire, 72 recipients of the local governments responded, showing a 96% response rate, and 74 (82.2%) of the KRC responded. The overall response rate was 88.5%. The opinions on the rental method of the reclaimed land were found to differ according to the geographic conditions of the reclaimed land, the construction conditions, and the time. Regarding the survey on crops preferred for cultivation, rice was highest in both local governments (61%) and KRC (46%). When cultivating field crops in reclaimed land, 56% of local governments and 57% of KRC considered salinity as the most problematic or resolvable problem. Regarding growing other field crops in reclaimed land, salt and drainage problems were recognized as the biggest obstacles in all reclaimed land. As for technologies that need to be applied first for the future agriculture of reclamation land, KRC responded with automatic water management (48%) and local governments responded with unmanned agricultural machinery (32%). In order to diversify the land use in the reclamation area, it is necessary to reduce salt damage and ensure systematic maintenance, employing, for example, automatic water management facilities and drainage improvement methods. The results of this study can set a land use direction for reclamation sites and provide useful information for use in various forms.

DEM-based numerical study on discharge behavior of EPB-TBM screw conveyor for rock (EPB-TBM 암반굴착시 스크류컨베이어의 배토 거동에 대한 DEM 기반 수치해석적 연구)

  • Lee, Gi-Jun;Kwon, Tae-Hyuk;Kim, Huntae
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.1
    • /
    • pp.127-136
    • /
    • 2019
  • Tunnel construction by TBMs should be supported by the performance of a screw conveyor in order to obtain the optimum penetration rate, so studies related to the screw conveyor performance have been being conducted. Compared to the study on the performance of the screw conveyor for the soil, however, the research on the performance of the screw conveyor for the rock is insufficient. Considering the domestic tunnel sites with more rock layers than soil layers, simulation of discharge of 6 types of rock chips by the screw conveyor was conducted using DEM. Regardless of the shape and volume of the rock chips, the discharge rates of the rock chips by the parallel placed screw conveyor at a speed of 10 RPM in the same rock mass were about 20% (standard deviation: 1.3%) of the maximum volume of discharge rate by the screw conveyor. It is expected that this study can be used as a reference material for screw conveyor design and operation in TBM excavations in rock masses.

Evaluation of the Optimal Grouser Shape Ratio of Dozer Considering the Ground Conditions (지반 특성을 고려한 도저의 최적 그라우저 형상비 평가)

  • Baek, Sung-Ha;Kwak, Tae-Young;Choi, Changho;Lee, Seong-Hwan
    • Journal of the Korean Geotechnical Society
    • /
    • v.37 no.3
    • /
    • pp.31-41
    • /
    • 2021
  • A dozer is a construction machinery used to move soil mass along large open tracts of land. Soil thrust generated on the soil-track interface determines the performance of the dozer; to improve the tractive performance of the dozer, the outer surface of the continuous-track is designed to protrude with grousers. In this study, we calculated soil thrust of the dozer equipped with grousers with various shape ratios, and evaluated the optimal grouser shape ratio considering ground conditions. Grouser generated additional soil thrust on the side of the continuous-track (e.g., side soil thrust) and converted the shearing surface (e.g., from soil-track interface to soil-soil interface), increasing the soil thrust of dozer by about 1.3 to 1.6 times. The effect of grouser's shape ratio on the soil thrust of dozer differed with the relative density of the ground. As the shape ratios of grouser increased, soil thrust of dozer decreased at the relative density of 40% and increased at the relative density of 80%. Based on these results, it can be concluded that the shape ratio of grouser severely affects the dozer's performance; thus, careful consideration of the optimal shape ratio of grouser is of great importance in the mechanical design, evaluation, and optimization of the undercarriage of dozers.

Effect of Vibration on Characteristics of Lightweight Air-Trapped Soil (진동이 경량기포토의 특성에 미치는 영향)

  • Lee, Young-Jun;Kim, Sung Won;Park, Lee Keun;Kim, Tae-Hyung
    • Journal of the Korean GEO-environmental Society
    • /
    • v.12 no.4
    • /
    • pp.5-15
    • /
    • 2011
  • This study is conducted to find out the effect of vibration on cure and compressive strength of lightweight Air Trapped Soil(ATS). If ATS is used next to a structure existed, the effect of vibration problems may be occurred, because there exist many sources of vibration such as pile driving, blasting and use of construction machinery. For example, if a road is expanded to reduce traffic congestion, it is expected that ATS's quality may be decreased due to vibration generated by cars moving on the road. Especially, because ATS has many air bubbles and needs a time for curing, the effect of vibration is more serious than we expected. So far, the effect of vibration on concrete has been conducted, but the study of ATS has not been conducted in detail. Therefore, for evaluating the effect of vibration on ATS during cure proceeds, unconfined compression tests are conducted on the samples prepared with different variables including vibration velocity, time when vibrated and mixing ratio. The results clearly show the effect of vibration on the characteristics of ATS.

Survey and model development of the mechanization for swine farming (양돈농가의 기계화 실태분석 및 모델개발)

  • 이성현;박원규;강창호;오권영
    • Journal of Bio-Environment Control
    • /
    • v.7 no.2
    • /
    • pp.91-108
    • /
    • 1998
  • This study was carried out to survey basic information of swine farms on the machine holdings. facility type. management of manure by farm scale and operation, and then to develop the mechanization model. Manual feeding was common for sows and nursing sows. but automation feeding was normally furnished for weaners. growing pigs and castrated male pigs. Water supplies was completely automated for all of the surveyed swine farms. Fully mechanized and automated system would not be feasible and affordable for the small scale farms breeding less than 500 heads. Because the environmental control for the nursing sows and weaner was important, some swine houses were constructed with the windowless type. However, the furnished rates ranged from 22.2% to 44.4% of the surveyed nursing sow and weaner houses at the farm scales. In the future, a computerized ventilation system would be commended for the efficient use of heat energy and to maintain the desirable temperature of swine buildings. Over-investment for large scale farm and over-crowded pigpen of small farm would cause wasting construction expenses and spreading epidermic diseases Hence, the size of swine building should follow the recommended scale. The fermentation drier was recommended for the manure management. Urine could be recycled or discharged after treating by the activated sludge process.

  • PDF

A Study on the Limits of Manufacturing Innovation and Policy Direction of SMEs in the 4th Industrial Revolution : Focusing on the Limitations and Examples of Pohang SME's Smart Factory Introduction (4차 산업혁명시대 지역 중소기업의 제조혁신 한계와 스마트공장 정책 방향성 연구: 포항지역 중소기업의 스마트공장 조사를 중심으로)

  • Kim, Eunyoung;Park, Munsu
    • Journal of Science and Technology Studies
    • /
    • v.18 no.2
    • /
    • pp.269-306
    • /
    • 2018
  • Through this study, it is aimed to derive the policy direction considering the characteristics of the present Smart Factory, the industrial condition of Pohang area, and the promotion field. Secondly, the questionnaire data of the regional enterprises will prepare for the improvement of the industrial structure and the implications for efficiency, and preparation for regional preparation and industrial changes in preparation for the next generation of production revolution. The construction of Smart Factory in Pohang can be divided into two major directions. First, it is analyzed that smart factory pilot projects are highly needed, focusing on competitive medical precision manufacturing field among the SMEs in the region, primary metal and nonmetal manufacturing industries, and other machinery fields. In addition, local SMEs are willing to introduce smart factories for reasons of quality improvement and cost reduction, and it is confirmed that they will actively promote employee training and expertise if they can upgrade continuously.

A Study on Development of Remote Crane Wire Rope Flaws Detection Systems (원격 크레인 와이어 로프 결함 탐지 시스템 개발에 관한 연구)

  • Min, Jeong-Tak;Lee, Jin-Woo;Lee, Kwon-Soon
    • Journal of Navigation and Port Research
    • /
    • v.27 no.1
    • /
    • pp.97-102
    • /
    • 2003
  • Wire ropes are used in a myriad of various industrial applications such as elevator, mine hoist, construction machinery, lift, and suspension bridge. Especially, the wire rope of crane is important component to container transfer. If it happens wire rope failures during the operation, it may lead to safety accident, economic loss by productivity decline and so on. To solve this problem, we developed remote wire rope fault detecting system, and this system is consisted of 3 parts that portable fault detecting part, signal processing part and remote monitoring part. All detected signal has external noise or disturbance according to circumstances. So, we applied to discrete wavelet transform to extract a signal from noisy data. It is verified that the detecting system by de-noising has good efficiency for inspecting faults of wire ropes in service. As a result, by developing this system, container terminal could reduce expense because of extension fo wire ropes exchange period and could competitive power. Also, this system is possible to apply in several field such as elevator, lift and so on.

Simulation analysis and evaluation of decontamination effect of different abrasive jet process parameters on radioactively contaminated metal

  • Lin Zhong;Jian Deng;Zhe-wen Zuo;Can-yu Huang;Bo Chen;Lin Lei;Ze-yong Lei;Jie-heng Lei;Mu Zhao;Yun-fei Hua
    • Nuclear Engineering and Technology
    • /
    • v.55 no.11
    • /
    • pp.3940-3955
    • /
    • 2023
  • A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: 60Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are Ф57 and Ф55; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable.