• Title/Summary/Keyword: working mechanism

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Research of Circuit Working Construction Elevator with Single-guide Rail and Multi-cages

  • Kun Zhang;Kaiqiang Wang;Di Li;Qing Sun;Zhen Ye;Wei Liu
    • International Journal of High-Rise Buildings
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    • v.11 no.2
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    • pp.137-144
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    • 2022
  • As one of the most important vertical transportation equipment in super high-rise buildings, the construction elevator directly affects the project period, cost, and effectiveness. The paper proposes a new construction elevator with single-guide rail and multi-cages. It can solve the problems of single construction elevator capacity shortage and efficacy decrease with height reduction, the occupancy of plan and elevation position of multiple construction elevators, and extension of total construction period by cycling operation of multi-cages on a single-guide rail. The paper focuses on the design and research of the main components of the equipment, such as the rotating guide rail mechanism, vertical bearing mast tie system, segmented electrical power supply system, group control scheduling system, and safety anti-collision system.

Effect of Injection Pressure on the Flash Boiling Spray from Simple Orifice Nozzle (인젝터 압력이 단공노즐 감압비등 분무에 미치는 영향)

  • Lee, Hyunchang;Cha, Hyunwoo;Kang, Donghyeon
    • Journal of ILASS-Korea
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    • v.27 no.1
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    • pp.42-49
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    • 2022
  • Flash boiling occurs in a couple of modern engineering systems and understanding its mechanism is important. In this experimental study, discharge coefficient of flash boiling spray from simple orifice nozzle was measured, and backlight imaging was acquired at injection pressure to 6.0 bar and temperature to 163℃ for the purpose. Pressurized water by pump was used for working fluid and was heated by electric heater and ejected through simple orifice nozzle diameter of 0.5 mm. High speed camera with long distance microscope was used for backlight imaging in two FoV having magnification of 3.3 and 0.64. The decrease of discharge coefficient according to degree of superheating and evolution of flash boiling spray imaged at various pressure and temperature were explained by the pressure field inside the injector.

Electrical Engineering Design Method Based on Neural Network and Application of Automatic Control System

  • Zhe, Zhang;Yongchang, Zhang
    • Journal of Information Processing Systems
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    • v.18 no.6
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    • pp.755-762
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    • 2022
  • The existing electrical engineering design method and the dynamic objective function in the application process of automatic control system fail to meet the unbounded condition, which affects the control tracking accuracy. In order to improve the tracking control accuracy, this paper studies the electrical engineering design method based on neural network and the application of automatic control system. This paper analyzes the structure and working mechanism of electrical engineering automation control system by an automation control model with main control objectives. Following the analysis, an optimal solution of controllability design and fault-tolerant control is figured out. The automatic control power coefficient is distributed based on an ideal control effect of system. According to the distribution results, an automatic control algorithm is based on neural network for accurate control. The experimental results show that the electrical automation control method based on neural network can significantly reduce the control following error to 3.62%, improve the accuracy of the electrical automation tracking control, thus meeting the actual production needs of electrical engineering automation control system.

A Study on the Risk of Fire Caused by Sparks during Grinding Operation (그라인딩 작업 중 발생하는 불티의 화재 예방에 관한 연구)

  • Seong-En Kim;Geun-Chul Lee;Kyong-Jin Park
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.5
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    • pp.751-756
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    • 2023
  • In this study, We investigated a fire case and performed an experiment to prevent fire from sparks that is generated during grinding operation. Before conduct the test, confirmed that the generating mechanism of fire-flakes in working grinder and the fire experiment was conducted using commonly tools, flammable materials in industrial field. in result, It could be measured scattering distance, temperature, ignition possibility by type of combustible materials. Based on the results of this study, We are expected to be used as basic data for fire prevention in grinding Industry.

Digital Transformation Requirements at Saudi Universities from Faculty Members' Perspectives

  • Taha Mansor Khawaji
    • International Journal of Computer Science & Network Security
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    • v.23 no.11
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    • pp.8-20
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    • 2023
  • The current study aims to determine digital transformation (organizational, technical, and human resources) requirements at Saudi universities from Umm Al-Qura University faculty members' perspectives. The researcher used a quantitative approach based on the descriptive analytical design. To answer the questions of the study, the researcher used the questionnaire as a data collection tool. The questionnaire was sent electronically to faculty members working in colleges and institutes affiliated with Umm Al-Qura University in Makkah Al-Mukarramah, Saudi Arabia. The questionnaire consisted of the three dimensions of digital transformation: organizational; technical; and human resources requirements. The results showed that requirements related to human resources came first with an average of 2.25 then the organizational requirements with an average of 1.95, and in the last, technical requirements came with an average of 1.64. In addition, some suggestions were given by the participants (faculty members) related to the mechanism that could contribute to implementing digital transformation at Saudi universities. Likewise, at the end of the study, the researcher has given some suggestions related to the implementation of digital transformation requirements at Saudi universities.

A study on the relationship between the movement of animation and heritage of modern mechanism (애니메이션의 움직임과 근대 기계론 전통의 상관관계 연구)

  • Kim, Takhoon;Han, Tae-Sik
    • Cartoon and Animation Studies
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    • s.30
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    • pp.27-57
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    • 2013
  • Animation which appeared with films in the late 19th century was a medium which came on obtaining nourishment from art historical style of modernism. However, the relation establishment between animation and modernism has been focused mainly on animation shapes, namely painted images. This sprang from explaining the relationship between animation and paintings, and for this reason, discussions of movements in animation were understood in tradition of chromophotograph of Muybridge and Jules Marey, or some characteristics owned by the live-action film. However, movements of animation were essentially different from the indexical sign of films or photogram, and objects of reproduction were different between them. Movements reproduced by animation are not ordinary movements, but expressions of or compressed movements and considerably systematic movements. As a result, these movements are far from reproduction of live-action film photogram. Rather, the logic of movements reproduced by animation comes near to controlling their motion scopes, time, distance etc. after dividing each part of the body. This is concluded in a standpoint of modern mechanism which is represented by Descartes and La Mettrie who tried to understand human body as a exchangeable machine. Design of modern mechanism ranging from modern society to industrial society and the age of modernism came to lead to analysis of physical motions of modern industrial society called composition of efficient movements understanding them as the law of nature rather than movements as nature. In the late 19th century, Taylor, F. W. and Gilbreth, Frank Bunker's studies of workers' working hours and 'motion study' were a way of constituting the frame of machine-human, which indicates that tradition of modern mechanism affected the entire modernism passing through industrial society. Further, we can see that motion studies conducted by them have almost similar characteristics to action analysis to study animation later in the name of 'timing'.

QoS Fairness in Multimedia Service using Wireless LAN (무선 랜 멀티미디어 서비스의 QoS 공정성 보장)

  • Jin, Hyun-Joon;Park, Nho-Kyung
    • Journal of IKEEE
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    • v.12 no.4
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    • pp.196-203
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    • 2008
  • The IEEE 802.11e working group has announced a new distributed MAC(Medium Access Control) called EDCA(Enhanced Distributed Channel Access) to provide service differentiation among classified traffics. In comparison with the 802.11 legacy MAC, the EDCA provides QoS mechanism by differentiated channel access which is called AC(Access Category) to the frames with different priorities. In multimedia applications, however, the EDCA has some difficulties to achieve QoS throughput because of using fixed AC parameters and never considers overall throughputs, i.e. fairness, for classified services. In this paper, AC parameter control technique is proposed to achieve overall QoS throughputs with differentiated services. The proposed technique controls AC parameters dynamically in real time. Simulation is used to verify the technique and the simulation shows that QoS fairness is improved by 13% in throughput deviation in multimedia environments including voice, video and data service.

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Pit Corrosion of SS420 Stainless Steel by Grain Boundary Sensitization (스테인레스강 SS420의 입계예민화에 의한 피트 부식)

  • Choe, Byung Hak;Lee, Bum Gyu;Jang, Hyeon Su;Park, Chan Sung;Kim, Jin Pyo;Park, Nam Gyu;Kim, Cheong In;Kim, Bo Mi
    • Korean Journal of Materials Research
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    • v.27 no.8
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    • pp.431-437
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    • 2017
  • This study investigated the surface pit corrosion of SS420J2 stainless steel accompanied by intergranular crack. To reveal the causes of surface pits and cracks, OM, SEM, and TEM analyses of the microstructures of the utilized SS420J2 were performed, as was simulated heat treatment. The intergranular cracks were found to have been induced by a grain boundary carbide of $(Cr,Fe)_{23}C_6$, which was identified by SEM/EDS and TEM diffraction analyses. The mechanism of grain boundary sensitization occurred at the position of the carbide, followed by its occurrence at the Cr depleted zone. The grain boundary carbide of $(Cr,Fe)_{23}C_6$ type precipitated during air cooling condition after a $1038^{\circ}C$ solid solution treatment. The carbide precipitate formation also accelerated at the band structure formed by cold working. Therefore, using manufacturing processes of cooling and cold working, it is difficult to protect SS420J2 stainless steel against surface pit corrosion. Several counter plans to fight pit corrosion by sensitization were suggested, involving alloying and manufacturing processes.

Output performance enhanced triboelectric nanogenerator with gear train support

  • Kim, Wook;Hwang, Hee Jae;Choi, Dukhyun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.415.2-415.2
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    • 2016
  • Triboelectric nanogenerator (TENG) is one of ways to convert mechanical energy sound, waves, wind, vibrations, and human motions to available electrical energy. The principal mechanism to generate electrical energy is based on contact electrification on material surface and electrostatic induction between electrodes. The performance of TENG are dependent on amount of the input mechanical energy and characteristics of triboelectric materials. Furthermore, the whole TENG system including mechanical structure and electrical system can effect on output performance of TENG. In this work, we investigated the effect of gear train on output performance and power conversion efficiency (PCE) of TENG under a given input energy. We applied the gear train on mechanical structure to improve the contact rate. We measured the output energy under a constant input energy by controlling the size of the working gear. We prepared gears with gear ratios (rin/rw) of 1, 1.7, and 5. Under the constant input energy, the voltage and current from our gear-based TENG system were enhanced up to the maximum of 3.6 times and 4.4 times, respectively. Also, the PCE was increased up to 7 times at input frequency of 1.5 Hz. In order to understand the effect of kinematic design on TENG system, we performed a capacitor experiment with rectification circuit that provide DC voltage and current. Under the input frequency of 4.5 Hz, we obtained a 3 times enhanced rectifying voltage at a gear ratio of 5. The measured capacitor voltage was enhanced up to about 8 fold in using our TENG system. It is attributed that our gear-based TENG system could improve simultaneously the magnitude as well as the generation time of output power, finally enhancing output energy. Therefore, our gear-based TENG system provided an effective way to enhance the PCE of TENGs operating at a given input energy.

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A Study on High Temperature Deformation Behavior of Spray-Formed High Speed Steels (분무주조 고속도공구강의 고온변형 거동에 관한 연구)

  • Ha, T.K.;Jung, J.Y.
    • Transactions of Materials Processing
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    • v.27 no.2
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    • pp.123-129
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    • 2018
  • In the present study, the mechanical behavior of the spray-formed high speed steel was investigated employing the internal variable theory of inelastic deformation. Special attention was focused on the effect of the microstructure evolution during the hot working process, such as the distribution of carbides to provide a basic database for the production condition of high speed steels with excellent properties. The billets of high speed steel ASP30TM were fabricated by a spray forming, and the subsequently hot-rolled and heat-treated process to obtain uniformly distributed carbide structure. As noted the spray-formed high speed steel showed relatively coarser carbides than hot-rolled and heat-treated one with fine and uniformly distributed carbide structure. The step strain rate tests and high temperature tensile tests were carried out on both the spray-formed and the hot-rolled specimens, to elucidate their high temperature deformation behavior. The spray-formed high speed steel showed much higher flow stress and lower elongation than the hot-rolled and heat-treated steel. During the tensile test at $900^{\circ}C$, the interruption of the deformation for 100 seconds was conducted to reveal that the recovery was a main dynamic deformation mechanism of spray formed high speed steel. The internal variable theory of the inelastic deformation was used to analyze data from the step strain rate tests, revealing that the activation energies for hot deformation of as-spray-formed and hot-worked steels, which were 157.1 and 278.9 kJ/mol, and which were corresponding to the dislocation core and lattice diffusions of ${\gamma}-Fe$, respectively.