• Title/Summary/Keyword: Stabilizing materials

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Physical and Mechanical Properties of Waterwaste Sludge and Stabilized Sludge (슬러지 및 안정화시킨 하수 슬러지의 물리적.역학적 특성)

  • 송창섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.41 no.6
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    • pp.97-104
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    • 1999
  • An experimental investigation was carried out to study the feasibility of using the stabiliozed sludge, as a backfill and cutoff-water materials for embankment structures. For stabilizing of sludge, hydrated lime and quick lime were used as additive, and a series of tests were performed on the sludge and the stabilized sludge to examine their physical and mechanical properties , compaction, compressive strength, hydraulic conuctivity and consolidation characteristics. From the test results, physical and mechanical properties of the stabilized sludge were improved as compared with the sludge. Especially from the viewpoint of physcial property, consolidation or settlement and cutoff-water, quick lime is more effective than the hydrated lime as a stabilization addtive. But, viewpoint of compaction and shear strength, hydrated lime is more effective than the quick lime as a atabilization additive. As a result of this study, it was found that the stabilized sludge can be developed the backfill and cutoff-water materials, improved the stabilizing method of sludge.

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Development of Display Content for Overload Prevention in the Crane Controller (크레인 컨트롤러에서의 전도방지를 위한 디스플레이 콘텐츠 개발)

  • Lee, Sang Young
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.3
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    • pp.87-95
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    • 2012
  • Up to now, industrial cranes play important roles as the effective machines to carry heavy loads in the manufacturing premise, in the construction field and so on. And, a crane is widely used not only to daily work but also to carry heavy materials efficiently in a construction site for prevention of accident. However, the crane operation is highly complicated even for experts. In this paper, we developed the content of the crane mounted on the controller. This content overload conditions in the operating environment for the crane operator to warn, and the operation of equipment has the capability to limit automatically. The content for crane controller is to alert the operator overload and to limit the operation of equipment for stabilizing capabilities. The content of the flexible algorithm is based on stabilizing controllers, PLC (Programmable Logic Controller) to connect for using the equipment and electrical control systems to ensure the safety of workers and to improve the ability to work possible.

Nanotubular Structure Formation on Ti-6Al-4V and Ti-Ta Alloy Surfaces by Electrochemical Methods

  • Lee, Kang;Choe, Han-Cheol;Ko, Yeong-Mu;Brantley, W.A.
    • Korean Journal of Metals and Materials
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    • v.50 no.2
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    • pp.164-170
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    • 2012
  • Nanotubular structure formation on the Ti-6Al-4V and Ti-Ta alloy surfaces by electrochemical methods has been studied using the anodizing method. A nanotube layer was formed on Ti alloys in 1.0 M $H_3PO_4$ electrolyte with small additions of $F^-$ ions. The nanotube nucleation and growth of the ${\alpha}$-phase and ${\beta}$-phase appeared differently, and showed different morphology for Cp-Ti, Ti-6Al-4V and Ti-Ta alloys. In the ${\alpha}$-phase of Cp-Ti and martensite ${\alpha}^{\prime}$ and in the ${\alpha}^{{\prime}{\prime}}$ and ${\beta}$-phase of the Ti-Ta alloy, the nanotube showed a clearly highly ordered $TiO_2$ layer. In the case of the Ti-Ta alloy, the pore size of the nanotube was smaller than that of the Cp-Ti due to the ${\beta}$-stabilizing Ta element. In the case of the Ti-6Al-4V alloy, the ${\alpha}$-phase showed a stable porous structure; the ${\beta}$-phase was dissolved entirely. The nanotube with two-size scale and high order showed itself on Ti-Ta alloys with increasing Ta content.

Stabilizing Properties of SiOF Film with Low Dielectric Constant by $N_2O$ Plasma Annealing ($N_2O$ 플라즈마 열처리에 의한 저유전율 SiOF 박막의 물성 안정화)

  • Kim, Yoon-Hae;Lee, Seok-Kiu;Kim, Sun-Oo;Kim, Hyeong-Joon
    • Korean Journal of Materials Research
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    • v.8 no.4
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    • pp.317-322
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    • 1998
  • The stabilization of low dielectric constant SiOF films prepared by conventional PECVD using TEOS and $C_2F_6$ was evaluated by the $N_2O$-plasma post-deposition annealing. Properties of SiOF film became unstable when it was air-exposed or heat-treated. Water absorption of SiOF films was increased as F content was increased due to the for¬mation of F -Si- F bonds. Also F content of SiOF films decreased after heat treatment. $N_2O$-plasma post-deposition annealing was proved to be effective on stabilizing SiOF films. which was mainly due to the formation of thin SiON layer near the top surface of films. However. the value of dielectric constant was greatly increased again when $N_2O$-plasma post-deposition annealing was done for a long time. To stabilize the SiOF films without an increase of dielec¬tric constant by $N_2O$- plasma post-deposition annealing. the annealing time should be kept the minimum value. to which stabilizing effects against air environment and heat treatment were preserved.

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Reinforcing Effect and Behaviors of Root-Pile in Heavy-Duty Direct Shear Test (대형직접전단시험에 의한 뿌리말뚝의 거동 및 보강효과)

  • Han, Jung-Geun;Jang, Sin-Nam
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.3
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    • pp.23-30
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    • 2002
  • In recently, using of steel reinforcements by reinforcing materials of the reinforced earth, micro-pile and root-pile etc,. is wide-spreading in the stabilizing control of cutting and embankment slopes, but the failure mechanism of reinforced earth as well as the effect of insert angles or types of reinforcement and others are not defined clearly. In this study, therefore heavy-duty direct shear tests were exercised on the reinforced soil and the non-reinforced soil, which was executed for research on the interaction of soil-reinforcement and theirs behavior. The hardness and softness and the standard sands were used for modeling of reinforced soil, the material constants for the computer simulation were estimated from the results of CD-Test. The effects of reinforcing and of friction increasing on the softness, area ratio of reinforcements is equal, were the better than them of the hardness, as well the reinforcing effects of shear strength without regard to the area ratio is much the same at $10^{\circ}$, insert angle of reinforced bar, differ from them of the existing study. Then, the results of numerical analysis showed that the behavior of reinforcements displayed bending resistance and shear resistance at $15^{\circ}$ and $30^{\circ}$, respectively. Also, the state of strain transfer was observed and the behavior of resistance mechanism on reinforcements presented almost the same them of landslides stabilizing pile.

Austenite Stability of Sintered Fe-based Alloy (철계 소결합금의 오스테나이트 안정성)

  • Choi, Seunggyu;Seo, Namhyuk;Jun, Junhyub;Son, Seung Bae;Lee, Seok-Jae
    • Journal of Powder Materials
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    • v.27 no.5
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    • pp.414-419
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    • 2020
  • In the present study, we investigated the austenite stability of a sintered Fe-based nanocrystalline alloy. The volume fraction of austenite was measured based on the X-ray diffraction data of sintered Fe-based nanocrystalline alloys, which were prepared by high-energy ball milling and spark plasma sintering. The sintered alloy samples showed a higher volume fraction of austenite at room temperature as compared to the equilibrium volume fraction of austenite obtained using thermodynamic calculations, which resulted from the nanosized crystalline structure of the sintered alloy. It was proved that the austenite stability of the sintered Fe-based alloy increased with a rise in the amount of austenite stabilizing elements such as Mn, Ni, and C; however, it increased more effectively with a decrease in the actual grain size. Furthermore, we proposed a new equation to predict the martensite starting temperature for sintered Fe-based alloys.

Self-Sensing Electrostatic Suspension System (자가 검출 방식을 이용한 정전 부상 시스템)

  • 정학근;최창환;박기환
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.6
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    • pp.454-461
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    • 2000
  • Electrostatic suspension offers an advantage of directly suspending various materials such as conductive materials, semiconductors and dielectric materials without any mechanical contacts. This is a specific feature compared with electromagnetic suspension which can suspend only ferro-magnetic material. In general, the electrostatic suspension systems require position sensors for stabilizing the suspended object. Therefore, a lot of displacement sensors and a switching circuit are required for moving the object through a long distance. In order to circumvent this problem, this paper proposes a self-sensing method which can provide the gap displacement between electrodes and suspended object without external sensors. Moreover a simple on-off controller is presented for stabilization. Experimental validation of the proposed scheme has been performed through the successful levitation of a 4-inch silicon wafer.

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Soil-Lime and Additives Stabilization (석회와 여러 첨가제에 의한 토질안정처리)

  • 민덕기;황광모;박근호
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.657-664
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    • 2000
  • Weak and soft compressible clay deposits are commonly found in natural subgrade soils. These Soils need to be stabilized for using the subbase materials of highway constructions. This paper presents that a chemical treatment using chemical additives comprised of sulfate(SO$_4$) and chloride(Cl) is evaluated for stabilizing soft clay deposits and lime. The physical and mechanical characteristics of soil-lime and additives are described by means of a laboratory study. The study results indicate that the presence of chlorides encouraged the efficiency of lime stabilization, and the use of calcium chloride with quicklime is the best additive for improving soil behavior. The treated soil with lime-calcium chloride can have the adaptability to the subbase materials of highway constructions.

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Fabrication of a UV laser micromachining platform with process-monitoring optical modules (공정 모니터링 광학모듈이 장착된 UV 레이저 미세가공 플랫폼 제작)

  • Sohn, H.;Lee, J.H.;Jeong, Y.W.;Kim, S.I.;Hahn, J.W.
    • Laser Solutions
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    • v.11 no.2
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    • pp.33-38
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    • 2008
  • Laser micromachining has increasingly been adopted in various advanced industries where the high-precision machining of large-area, high-density and multi-layered components is in a strong demand. To effectively meet the requirements, the laser micromachining process must be carefully monitored. In order to facilitate the development of a new laser micromachining process and/or a new system, we have fabricated a UV laser micromachining platform that is equipped with optical modules for monitoring the process online. They include a laser power stabilizing module, a module for laser-induced breakdown spectroscopy, and an auto-focusing module.

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Intravenous catheter flanges as an external nasal stent: a novel technique

  • Shibani A. Nerurkar;Subramania Iyer;Arjun Krishnadas;Pramod Subash
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.2
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    • pp.116-120
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    • 2024
  • External nasal splints are commonly used for immobilization following nasal fracture reduction or rhinoplasty procedures. The literature documents the use of various materials like thermoplastic materials, aluminum, Orthoplast, fiberglass, plaster of Paris, and polyvinyl siloxane. These materials are bulky, time-consuming, expensive, and cumbersome to use, and have been associated with complications including contact dermatitis and epidermolysis. Furthermore, they cannot be retained if the situation warrants prolonged stabilization and immobilization. We introduce a new technique using readily available scalp vein catheter flanges as an external nasal stent. The technique is easy to master, inexpensive, and limits edema and ecchymosis, while stabilizing the reconstructed nasal skeleton in position during the healing period.