• Title/Summary/Keyword: anchoring stability

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Flexible bistable chiral splay nematic display mode using reactive mesogens

  • Bae, Kwang-Soo;Lee, You-Jin;You, Chang-Jae;Kim, Jae-Hoon
    • Journal of Information Display
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    • v.12 no.4
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    • pp.195-198
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    • 2011
  • Proposed herein is a flexible bistable chiral splay nematic display mode with an enhanced memory retention time under external distortion. By adopting the polymerized reactive-mesogen structure mixed in a liquid crystal layer, local anchoring energy is generated on the boundary between the polymer structures, and the relaxation from the ${\pi}$-twisted state to the initial splay state could be interrupted. As a result, the memory retention time becomes significantly longer, and the stability against the external distortion is enhanced.

Linear regression analysis for factors influencing displacement of high-filled embankment slopes

  • Zhang, Guangcheng;Tan, Jiansong;Zhang, Lu;Xiang, Yong
    • Geomechanics and Engineering
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    • v.8 no.4
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    • pp.511-521
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    • 2015
  • It is a common failure type that high-filled embankment slope sideslips. The deformation mechanism and factors influencing the sideslip of embankment slope is the key to reduce the probability of this kind of engineering disaster. Taking Liujiawan high-filled embankment slope as an example, the deformation and failure characteristics of embankment slope and sheet-pile wall are studied, and the factors influencing instability are analyzed, then the correlation of deformation rate of the anti-slide plies and each factor is calculated with multivariate linear regression analysis. The result shows that: (1) The length of anchoring segment is not long enough, and displacement direction of embankment and retaining structure are perpendicular to the trend of the highway; (2) The length of the cantilever segment is so large that the active earth pressures behind the piles are very large. Additionally, the surface drainage is not smooth, which leads to form a potential sliding zone between bottom of the backfill and the primary surface; (3) The thickness of the backfill and the length of the anti-slide pile cantilever segment have positive correlation with the deformation whereas the thickness of anti-slide pile through mudstone has a negative correlation with the deformation. On the other hand the surface water is a little disadvantage on the embankment stability.

23' LCD TV by using ALT plasma beam alignment technology

  • Lee, C.Y.;Tang, H.C.;Chen, C.W.;Shih, Y.J.;Liu, C.H.;Lin, C.H.;Yang, K.H.;Lin, S.H.;Chang, H.C.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.776-779
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    • 2006
  • The alignment of liquid crystal (LC) is one of the key issues of liquid crystal display (LCD) technologies. In this study, we aligned polyimide (as the LC alignment layer) by ALT plasma beam and to realize the stability and characteristics of this technology. The characteristics such as anchoring energy, pre-tilt angle, voltage holding ratio(VHR) and residual direct current(Rdc) were discussed. Besides, we applied it to the in plane switch (IPS) mode 23" WXGA real panel, the performance parameters and electrical properties were measured and compared with those of rubbing alignment. From the result, we demonstrated a successful LC alignment treatment process in real panel by ALT plasma beam.

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Holding Mechanism of Anchor System for Fisheries Facilities (계류기초의 파주력 산정에 관한 연구)

  • Jung, Jin-Ho;Ryu, Cheong-Ro;Kim, Jong-Gyu
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.2
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    • pp.132-147
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    • 1996
  • The optimal design of floating type fisheries facilities in the open sea is demanded considering with the severe hydrodynamic forces on floating body, mooring tension and holding force of anchor. For conserving the facilities in most effective state, design and selection of anchor system is one of the most important fundamental subject. To enhance the design procedure of anchor system the holding forces of anchor are investigated by the hydraulic model test and are compared with the typical conventional results for various anchors. Applicability of previous estimation methods of holding force are checked and holding mechanism of anchor is discussed. Using the results a new computational concept of holding force is suggested considering mainly the effects of passive soil pressure (resistance), steady soil pressure, and surface friction etc. The new estimation method is proved as a feasible one by comparing the results of hydraulic model experiments. Applicability of various anchors to the anchor system on open sea fisheries structures is comprehensively reviewed using the present model tests and previous study results in the viewpoint of economy, construction and stability etc. Using the results, fundamental anchoring system design procedures are suggested to apply huge marine ranching complex with increase of the holding capacity of anchor under the optimum cost.

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Development of umbrella anchor approach in terms of the requirements of field application

  • Evirgen, Burak;Tuncan, Ahmet;Tuncan, Mustafa
    • Geomechanics and Engineering
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    • v.18 no.3
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    • pp.277-289
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    • 2019
  • In this study, an innovative anchoring approach has been developed dealing with all relevant aspects in consideration of previous works. An ultimate pulling force calculation of anchor is presented from a geotechnical point of view. The proposed umbrella anchor focuses not only on the friction resistance capacity, but also on the axial capacity of the composite end structure and the friction capacity occurring around the wedge. Even though the theoretical background is proposed, in-situ application requires high-level mechanical design. Hence, the required parts have been carefully improved and are composed of anchor body, anchor cap, connection brackets, cutter vanes, open-close ring, support elements and grouting system. Besides, stretcher element made of aramid fabric, interior grouting system, guide tube and cable-locking apparatus are the unique parts of this design. The production and placement steps of real sized anchors are explained in detail. Experimental results of 52 pullout tests on the weak dry soils and 12 in-situ tests inside natural soil indicate that the proposed approach is conservative and its peak pullout value is directly limited by a maximum strength of anchored soil layer if other failure possibilities are eliminated. Umbrella anchor is an alternative to conventional anchor applications used in all types of soils. It not only provides time and workmanship benefits, but also a high level of economic gain and safe design.

Stability of a Natural Slope in Sedimentary Rocks (퇴적암 지역의 자연사면 안정성)

  • 권오일;김교원;박덕근
    • The Journal of Engineering Geology
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    • v.10 no.3
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    • pp.205-216
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    • 2000
  • An unstable natural slope located at Icheon-Ri, Dasa-Eup, Dalseong-Kun which has been severely cracked during heavy rain fall in September, 1998, was investigated and analysed for remedial measures. Various geological data were obtained by performing a surface geological survey, a ground penetrating radar(GPR) exploration, four geotechnical borings with field and laboratory tests, and the precipitation records were also reviewed. Based on the these data, the probable sliding plane was determined as a bedding plane with dip angle of 20 to 25 degrees between sandstone and shale layers at depth of 6 to 8 meters. By performing back analyses with the limit equilibrium method, the friction angle and cohesion of the sliding plane were determined as 18$^{\circ}$ and 0, respectively. Based on these results, a series of stability analyses such as stereo-graphic projection method, limiting equilibrium method and numerical method were carried out. The remedial measures for the unstable slope were selected based on the results of the limit equilibrium analyses by considering various conditions expected at the site. Ground grouting or anchoring method with proper surface drainage systems could be employed for the long term safety of the slope.

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Synthesis, Characterizations, and Applications of Metal-Ions Incorporated High Quality MCM-41 Catalysts (고품질 금속 이온 첨가 MCM-41 분자체 촉매의 제법, 특성화 및 응용 반응)

  • Lim, Steven S.;Haller, Gary L.
    • Korean Chemical Engineering Research
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    • v.51 no.4
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    • pp.443-454
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    • 2013
  • Various metal ions (transition and base metals) incorporated MCM-41 catalysts can be synthesized using colloidal and soluble silica with non-sodium involved process. Transition metal ion-typically $V^{5+}$, $Co^{2+}$, and $Ni^{2+}$-incorporated MCM-41 catalysts were synthesized by isomorphous substitution of Si ions in the framework. Each incorporated metal ion created a single species in the silica framework, single-site solid catalyst, showing a substantial stability in reduction and catalytic activity. Radius of pore curvature effect was investigated with Co-MCM-41 by temperature programmed reduction (TPR). The size of metallic Co clusters, sub-nanometer, could be controlled by a proper reduction treatment of Co-MCM-41 having different pore size and the initial pH adjustment of the Co-MCM-41 synthesis solution. These small metallic clusters showed a high stability under a harsh reaction condition without serious migration, resulting from a direct anchoring of small metallic clusters to the partially or unreduced metal ions on the surface. After a complete reduction, partial occlusion of the metallic cluster surface by amorphous silica stabilized the particles against aggregations. As a probe reaction of particle size sensitivity, carbon single wall nanotubes (SWNT) were synthesized using Co-MCM-41. A metallic cluster stability test was performed by CO methanation using Co- and Ni-MCM-41. Methanol and methane partial oxidations were carried out with V-MCM-41, and the radius of pore curvature effect on the catalytic activity was investigated.

Structural and Layout Design Optimization of Ecosystem Control Structures(1) -Characteristics of Mooring Force and Motion Control of the Longline Type Scallop Culturing Facility- (생태계 제어 시설물의 설계 및 배치 최적화(1) -연승식 양식시설의 계류력 특성 및 동요저감에 관한 연구-)

  • RYU Cheong-Ro;KIM Hyeon-Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.1
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    • pp.35-48
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    • 1995
  • To develop the optimal design method for the longline type scallop culturing facilities in the open sea numerical calculations and hydraulic model experiments are carried out for the stability and function optimization. Using the results for the motion and tension of the facilities, stable design concepts and effects of motion control system by vertical anchor and resistance discs art discussed. The results of this study that can be applied to the design are as follows: 1) Total external forces by design wave $(H_{1/3}\;=\;6,7\;m,\;T_{1/3}\;=\;12sec)$ at the coastal waters of Jumunjin for unit facility (one main line) are estimated to 5-20 tons, and required anchor weights are 10-40 tons in the case of 2-point mooring system. Though the present facilities are stable to steady currents, but is unstable to the extreme wave condition of return period of 10 years. 2) The dimensions and depth of array systems must be designed considering the ecological environments as well as the physical characteristics including the mooring and holding forces that are proportional to the length and relative depth of main line to wave length, and the number of buoys and nets. 3) Oscillation of the facility is influenced by water particle motion and the weight of hanging net, and is excited at both edge, especially at the lee side. To reduce the motion of the nets, the vertical anchoring system and the resistence disc method are recommended by the experimental results, 4) The damage of rope near the anchor by abrasion should be prevented using the ring-type connection parts or anchor chains.

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Effects of syllable structure and prominence on the alignment and the scaling of the phrase-initial rising tone in Seoul Korean: A preliminary study

  • Kim, Sahyang
    • Phonetics and Speech Sciences
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    • v.7 no.4
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    • pp.139-145
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    • 2015
  • The present study investigates the effects of syllable structure and prosodic prominence on the patterns of tonal alignment and scaling of the phrase-initial rise in Seoul Korean. Two syllable structures (Onset (/#CVC.../ as in minsa) vs. No-onset (/#VC.../ as in insa)) and two prominence conditions (Focus vs. Neutral) were considered. Results showed that the alignment of the L and the H tones in the phrase-initial rise was affected by syllable structure but not by prominence. The time of L was before the vowel onset of the first syllable in the Onset condition (i.e., within the onset consonant) and it was after the vowel onset in the No-onset condition. The difference was attributable to the fact that the initial L was anchored at a fixed distance from the phrase boundary, which was about 30ms after the onset of the syllable in both cases. The time of H was also consistently observed about 20ms after the second vowel onset (i.e., /a/ in minsa/insa). Moreover, the rise time (the duration from the L to the H tones) was longer as the local syllable duration became longer due to different syllable structure and prominence conditions. Taken together, the results provide a support for the segmental anchoring hypothesis, which claims that both the beginning and the end of F0 movement are consistently aligned with segmental 'anchor' points with relatively high stability (Ladd et al., 1999). Results also showed that the scaling of the early rise was slightly influenced by syllable structure but not by prominence. The differences between the results of the current study and a previous study (Cho, 2011) are further discussed.

Arthroscopic Capsulolabral Repair Using Absorbable Suture-Anchor for the Traumatic Anterior Instability of Shoulder (흡수성 suture-anchor를 이용한 견관절 전방 불안정성의 재건술)

  • Kim Seung-Ki;Song In-Soo;Seo Hyun Mo;Moon Myung-Sang;Lin Guang
    • Clinics in Shoulder and Elbow
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    • v.7 no.2
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    • pp.65-69
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    • 2004
  • Purpose: The purpose of this study is to evaluate the short-term clinical outcome of the capsulolabral repair using absorbable suture anchor in traumatic anterior instability of shoulder. Materials and Methods: From June 2000 to September 2001, 15 shoulders with recurrent anterior instability were operated with arthroscopic Bankart repair using absorbable suture-anchor 'PANALOK' (Mitek, westwood, MA), and were followed up over 1 year (average; 13 months). The mean age was 23-years. There were fourteen males and one female. The mean duration from the initial symptoms to the operation was 24 months. Associated pathologies were Hill-Sachs defect in 12 cases, SLAP in 6 cases, and partial rotator cuff tear in 2 cases. The results were evaluated by patien's satisfaction, Modified Rowe Score in regard to joint stability, mobility, pain and function in comparison with the preoperative ones, and other complications. Results: At the last follow-up, the total Rowe Score increased from 38 points to 92 points. There were no recurrence and 14 patients among 15 patients gained pre-operative level of sports activity and no other complications. Conclusion: Effective capsulolabral repair could be obtained by the absorbable anchoring without any untoward complications. This procedure is simple and safe one and this system can be a good substitute for the metallic anchor.