• Title/Summary/Keyword: Soft-Hard

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A Comparison of Thermal Performance of Double Low-E Glazing Window according to Various Material (더블로이유리 적용 창호의 구성요소에 따른 단열성능 비교 실험)

  • Jang, Cheol-Yong;Ahn, Byung-Lip;Kim, Chi-Hoon;Kim, Jun-Sub;Lee, Sung-Jae
    • 한국태양에너지학회:학술대회논문집
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    • 2011.04a
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    • pp.133-137
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    • 2011
  • Low-e glazing is classified as soft low-e glazing and hard low-e glazing. Hard low-e glazing can be temperable and its handling is comfortable because its coating film is a oxide film generated at high temperatures. But there is a fatal weakness that its insulation performance and shielding performance are lower compared to soft low-e glazing by low electrical conductivity of coating film. Soft low-e glazing is excellent because its coating film consists of Ag that is excellent electrical conductivity and it has strength that can supply various product consumers want. But soft low-e glazing has weaknesses that temperable and handling are difficult because Ag is oxidized easily. Therefore this study analyzes thermal performance of glazing by changing filling gas according to applying low-e glazing through simulation to judge performance before making sample. After this process, a comparative experimental study was done through TVS by making temperable low-e glazing.

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Poly(ether-ester) Multiblock Copolymers Based on Poly(oxymethylene-alt-oxyalkylene) Glycols

  • Kim, Jin-Bong;Chun, Jae-Hwan;Kim, Dong-Hee;Park, Yun-Hee;Lee, Moo-Sung
    • Macromolecular Research
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    • v.10 no.4
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    • pp.230-235
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    • 2002
  • Alternating polyols of oxymethylene and oxyalkylene were synthesized and used as precursors for thermoplastic poly(ether-ester) elastomers (TPEs). The polyols were synthesized by reacting diols having different methylene units with dichloromethane in the presence of a phase transfer catalyst. The number of methylene units in the alkylene oxides was varied from 3 to 6. TPEs were prepared using the polyols as soft segments and poly(butylene terephthalate) units as hard segments. The polyols and TPEs synthesized were characterized using FTIR, NMR, GPC, DSC, and polarized optical microscopy. The polyols showed a profound odd-even effect on the melting (T$_{m}$) and glass transition temperatures (T$_{g}$). Polyols with odd numbers of methylene groups in the alkylene units have higher transition temperatures than polyols with odd number of methylene groups. The tendency is still kept in TPEs, even though the T$_{g}$ of soft segment in TPEs are slightly higher than those of corresponding neat polyols. The T$_{m}$ and T$_{g}$ of soft segments are almost constant in the range of 20 to 60 wt % contents of soft segments. On the other hand, the normalized heat of fusion of hard segment decreased with increasing the content of loft segment.ent.t.ent.

On optimal design of soft-decision multistage detectors for asynchronous DS/CDMA systems (비동기 DS/CDMA 시스템을 위한 연판정 다단 검출기의 최적 설계)

  • 고정훈;주정석;이용훈
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.2035-2042
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    • 1997
  • We consider the design of soft decision functions for each stage of multistage detection for coherent demodulation in an asynchronous code-division multiple-access(CDMA) system. In particular, the sigmoid function, which is shown to be optimal under the mean square error(MSE) criterion, andmultilevel quantizers that best approximate the sigmoid function are derived. At each stage of multistage detection, the parameters of these decision functions are adjusted depending on estimated input statistics. Computer simulation results demonstrate that multistage detectors employing these soft decision functions perform considerably better than those with hard decision.

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Simultaneous Hard Tissue and Soft Tissue Graft with Dental Implant Placement and Provisionalization: A Case Report

  • Hyunjae Kim;Young-Dan Cho;Sungtae Kim
    • Journal of Korean Dental Science
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    • v.17 no.2
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    • pp.84-91
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    • 2024
  • Achieving both esthetic and functional implant rehabilitation is crucial for the successful treatment of the anterior maxilla. Adequate peri-implant alveolar bone and soft tissue are essential for optimal rehabilitation of the esthetic area, and there is a direct association between the implant position and prosthetic outcomes. Immediate provisionalization may also be advantageous when combined with augmentation. This case report described the implant placement in a 25-year-old female patient who had lost her right maxillary lateral incisor (#12) due to trauma-induced avulsion. The treatment involved simultaneous grafting and collagenated, deproteinized bovine bone mineral, along with subepithelial connective tissue taken from the right maxillary tuberosity. A polyetheretherketone abutment and non-functional immediate provisionalization were performed by removing both the proximal and occlusal contacts on the composite resin crown. Clinical and radiographic evaluations revealed maintenance of stable ridge contour aspects for six months following surgical treatment. In summary, implant rehabilitation in the esthetic zone can be successful using simultaneous soft and hard tissue grafts. Moreover, soft tissue stabilization post-subepithelial connective tissue grafting can be achieved through early or immediate visualization, along with immediate implant placement.

Structure and Properties of Segmented Block Copolyetheresters Based on PBT and PTMGT. 1. Thermal Properties of Dynamically Crystallized Samples

  • Jeon, Byoung-Yeol;Baik, Doo-Hyun
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.10a
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    • pp.29-32
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    • 1998
  • Segmented block copolyetheresters defined as copolymers having sequences of alternating polyester hard blocks and polyether soft blocks create labile physical cross-links upon crystallization of hard polyester blocks Since the nature of the physical interlocking is a crystallite formed exclusively from the crystallizable hard segment, the basic understanding of interrelationship between crystallization condition and phase morphology is very important for the property control of the segmented block copolyetheresters. (omitted)

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Characteristics of species richness and diversity of woody vegetation in the natural rivers in Korea and its meaning to restoration design in flood plains

  • Bang, Je-Yong;Hu, Un-Bok;Kim, Hyea-Ju;You, Young-Han
    • Korean Journal of Environment and Ecology
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    • v.29 no.1
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    • pp.62-68
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    • 2015
  • In order to get basic data for flood plain restoration, we surveyed the woody vegetation in Korean natural rivers and analyzed the species' characteristics with regards to patterns of richness and diversity. These characteristics were higher in hard wood forests than those in soft wood forests, such as Salix spp. community. Futhermore, they were the highest in the Prunus sargentii-Pinus densiflora community(H' 1.095), and the lowest in the Carpinus laxiflora community(H' 0.118) among the hard wood forests. Species' richness diversity were the highest in the Salix gracilistyla community, but the lowest in the S. koriyangi community or S. koreensis community among the soft wood forests. With regards to the dominant index, just one community is over 0.9, 13 communities are between 0.3-0.7 and 15 communities are less than 0.3. The Salix koreensis community was the highest at 0.931, and Prunus sargentii-Pinus densiflora community was the lowest at 0.13. Species' richness and diversity was significantly correlated with tree layer coverages and degree of slope. These results mean that in order to increase plant species diversity in flood plains planted hard woody trees, such as oaks and fir, are needed to suit environmental conditions with steeper slope and lower canopy coverage.

Integrated Concurrency Control Protocol for Hard and Soft Real-Time Transactions (하드와 소프트 실시간 트랜잭션을 위한 통합된 동시성제어 기법)

  • Hong, Seok-Hee
    • The Journal of the Korea Contents Association
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    • v.8 no.2
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    • pp.57-66
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    • 2008
  • Most concurrency control protocols have been devised for resolving data conflicts among real-time transactions of a single type. Recent real-time database systems should support various types of real-time transactions due to needs of many different types of applications and steady improvement of hardware. In this paper, we propose integrated concurrency control protocol to resolve data conflicts among hard and soft real-time transactions. Our proposed protocol, based on PCP(Priority Ceiling Protocol) for a hard real-time transactions and MVPR(Multiversion with Precedence Relationship), guarantees that hard real-time transactions meet their deadline, and decreases the deadline miss ratio of soft real-time transactions. We also proved that the proposed protocol guarantees serializable schedules and no deadlocks. The performance of the proposed protocol has been compared with other real-time concurrency protocols.

Effect of Surface Environment on Front Squat of Crossfit Athletes (지면환경이 크로스핏 선수의 프론트 스쿼트에 미치는 영향)

  • Jang, Yootae;Yoon, Sukhoon
    • Korean Journal of Applied Biomechanics
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    • v.32 no.2
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    • pp.49-55
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    • 2022
  • Objective: This study aims to verify the front squat motions using by two different surfaces, thereby elucidating the grounds for effective training environment that can minimize the risk of injury. Method: Total of 10 healthy male crossfit athletes were recruited for this study (age: 32.30 ± 3.05 yrs., height: 173.70 ± 5.12 cm, body mass: 82.40 ± 6.31 kg, 1RM: 160 ± 13.80 kg). All participants are those who know how to do front squats well with more than five years of crossfit athlete experience. All participants have sufficient experience in front squats on two types of surface which are soft surface (SS) and hard surface (HS). In each surface, participant perform 10reps of the front squat with 80% of the pre-measured 1RM. A 3-dimensional motion analysis with 8 infrared cameras and 2 channels of EMG was performed in this study. Paired sample t-test was used for statistical verification between two surfaces. The significant level was set at α=.05. Results: The significantly decreased rectus femoris muscle activation was found in SS compared with that of HS on phase 1 (p<.05). Also, ROM of ankle joint was significantly increased in the SS compare with that of HS on phase 1 (p<.05). The muscle activity ratio of gluteus maximus/rectus femoris showed a significant difference only in SS compared with that of HS on phase 1 (p<.05). Conclusion: In conclusion, Korean crossfit boxes should consider the use of hard surface, which has a relatively less risk of injury than soft surface, in selecting flooring materials. For the Crossfit athletes, they are also considered appropriate to train on a relatively hard surface.

A Ringing Surge Clamper Type Active Auxiliary Edge-Resonant DC Link Snubber-Assisted Three-Phase Soft-Switching Inverter using IGBT-IPM for AC Servo Driver

  • Yoshitsugu, Junji;Yoshida, Masanobu;Hiraki, Eiji;Inoue, Kenji;Ahmed, Tarek;Nakaoka, Mutsuo
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.2B no.3
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    • pp.115-124
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    • 2002
  • This paper presents an active auxiliary edge-resonant DC link snubber with a ringing surge damper and a three-phase voltage source type zero voltage soft-switching inverter with the resonat snubber treated here for the AC servo motor driver applications. The operation of the active auxiliary edge-resonant DC link snubber circuit with PWM voltage is described, together with the practical design method to select its circuit parameters. The three-phase voltage source type soft-switching inverter with a single edge-resonant DC link snubber treated here is evaluated and discussed for the small-scale permanent magnet (PM) type-AC servo motor driver from an experimental point of view. In addition to these, the AC motor stator current and its motor speed response for the proposed three-phase soft-switching inverter employing Intelligent Power Module(IPM) based on IGBTS are compared with those of the conventional three-phase hard-switching inverter using IPM. The practical effectiveness of the three-phase soft-switching inverter-fed permanent magnet type AC motor speed tracking servo driver is proven on the basis of the common mode current in a novel type three-phase soft-switching inverter-fed AC motor side and the conductive noise on the mains terminal interface voltage as compared with those of the conventional three-phase hard-switching inverter-fed permanent magnet type AC servo motor driver for the speed tracking applications.

REAPPRAISAL OF SOFT TISSUE PREDICTION IN ORTHOGNATHIC SURGERY FOR MANDIBULAR PROGNATHISM (외과적 악교절수술에 있어서 측모연조직예측의 재평가에 대한 연구)

  • Chung, Moo-Hyeok;Nam, Il-Woo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.13 no.1
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    • pp.37-43
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    • 1991
  • Cephalometric prediction tracing is the preoperative double checking procedure which can predict bony and soft tissue change. Soft tissue profile prediction is routinely performed according to the known ratios of the soft to hard tissue movement which can vary considerably in each individual. Besides interindividual variation of the ratios of the soft to hard tissue change, actual results of the postoperative soft tissue profile can reflect other important modifying factors if it is compared with prediction tracing used. The purpose of this study is to compare soft tissue prediction tracing used with postoperative tracing and to find intervening modifying factor via serial tracing. Review of 30 prediction tracing showed that the most important factor contributing to prodiction tracing inaccuracy was the skeletal and dental relapse. And, some factors which may be responsible for prediction tracing inaccuracy were discussed.

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