• Title/Summary/Keyword: filling performance

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Water Storage and Intake Performance of Gabion Weirs during Recharge (인공함양 원수확보를 위한 돌망태 보의 저류 및 취수성능에 관한 연구)

  • Han, Il Yeong;Kim, Gyoo Bum
    • The Journal of Engineering Geology
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    • v.29 no.4
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    • pp.393-403
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    • 2019
  • The water-storage performance of an intake weir can be evaluated by stage-discharge ratings. The stage-discharge rating of a gabion weir depends on the physical characteristics of the filling materials. This study reviewed existing discharge formulae for the evaluation of the water-storage performance of gabion weirs. A previously published relationship between the characteristics of filling materials and experimental constants was adapted for stage-discharge rating. The mean size of the filling material is the most influential factor for the water intake and water-storage performance of gabion weirs.

An Experimental Study on the Heat Transfer Characteristics of Stainless-Acetone Heat Pipe (스테인리스-아세톤 히트파이프의 열전달 특성에 관한 실험적 연구)

  • Kang, K. C.;Kim, Y. J.;Ryou, Y. S.;Baek, Y.;Rhee, K. J.
    • Journal of Biosystems Engineering
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    • v.25 no.6
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    • pp.489-496
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    • 2000
  • This study was conducted in order to find an ideal working fluid kind and a proper filling amount in the heat pipe as well as an inclined angle of heat pipe when they are placed to recover exhaust gas heat in the hot air heater. Followings are the findings of this research. 1. Of the four different working fluids-gasoline kerosene distilled water and acetone-acetone filled heat pipe showed the best performance giving out more homogeneous temperature profile on the radiating part than the kerosene and gasoline heat pipe an carrying out heat transmitting function better than the distilled water heat pipe by 10~2$0^{\circ}C$ higher on the radiating part. Acetone would be a good choice for recycling of exhaust gas heat in the hot air heater. 2. Of the filling amount of working fluid inside the heat pipes dry-out situations possible caused by insufficient filling were found in the filling amount of 5, 7.5 and 10% heat pipes as heat supply rate increases gradually in the range of 50 to 15kJ/sec. but no dry-out and stabilized heat transmitting performance occurred in the heat pipes of 12.5 and 15% filling at the same heat supply rate. It recommends that filling amount shall exceed 12.5% at least with the working fluids of this experiment. 3. The test revealed that the heat transmitting performance of heat pipe was more affected by filling amount rather than inclined angle.

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Technical Trend of TSV(Through Silicon Via) Filling for 3D Wafer Electric Packaging (3D 웨이퍼 전자접합을 위한 관통 비아홀의 충전 기술 동향)

  • Ko, Young-Ki;Ko, Yong-Ho;Bang, Jung-Hwan;Lee, Chang-Woo
    • Journal of Welding and Joining
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    • v.32 no.3
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    • pp.19-26
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    • 2014
  • Through Silicon Via (TSV) technology is the shortest interconnection technology which is compared with conventional wire bonding interconnection technology. Recently, this technology has been also noticed for the miniaturization of electronic devices, multi-functional and high performance. The short interconnection length of TSV achieve can implement a high density and power efficiency. Among the TSV technology, TSV filling process is important technology because the cost of TSV technology is depended on the filling process time and reliability. Various filling methods have been developed like as Cu electroplating method, molten solder insert method and Ti/W deposition method. In this paper, various TSV filling methods were introduced and each filling materials were discussed.

Improved Consistency and Productivity by Aeration Filling Technology and High Performance Powder Mixes

  • Larsson, Mats;Solimanjad, Naghi;Dahlberg, Mikael;Takeda, Yoshinubu;Kondoh, Mikio
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.742-743
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    • 2006
  • Filling of the tool die directly influences dimensional tolerances and density variation. To minimize the variations in filling, both within different sections of the cavity and from part to part, are of great importance for produce high quality P/M parts. Filling of the tool die is also one of the limiting factors in the productivity in powder pressing. By using aeration filling in combination with bonded powder mixes, both weight scatter and productivity can be improved. In this presentation results are presented showing the benefit of using aeration filling for different types of powders

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Packing density and filling effect of limestone fines

  • Kwan, A.K.H.;McKinley, M.
    • Advances in concrete construction
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    • v.2 no.3
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    • pp.209-227
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    • 2014
  • The use of limestone fines (LF) in mortar and concrete can in certain ways improve performance and thus has become more and more commonplace. However, although LF is generally regarded as a filler, it is up to now not clear how much filling effect it could have and how best the filling effect could be utilized. Herein, the packing density and filling effect of LF were studied by measuring the packing densities of LF, (LF + cement) blends and (LF + cement + fine aggregate) blends under dry and wet conditions, and measuring the performance of mortars made with various amounts of LF added. It was found that the addition of LF would not significantly increase the packing density of (LF + cement) blends but would fill into the paste to increase the paste volume and paste film thickness, and improve the flow spread and strength of mortar.

Analysis of Cell Performance with Varied Electrolyte Species and Amounts in a Molten Carbonate Fuel Cell

  • Lee, Ki-Jeong;Kim, Yu-Jeong;Koomson, Samuel;Lee, Choong-Gon
    • Journal of Electrochemical Science and Technology
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    • v.9 no.2
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    • pp.141-148
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    • 2018
  • This study evaluated the performance characteristics of varied electrolyte species and amounts in a molten carbonate fuel cell (MCFC). Coin-type MCFCs were used at the condition of $650^{\circ}C$ and 1 atm. In order to measure the effects of varied electrolyte species and amounts, electrolytes of $(Li+K)_2CO_3$ and $(Li+Na)_2CO_3$ were selected and the amounts of 1.5 g, 2.0 g, 3.0 g, and 4.0 g were used. Insignificant performance differences were observed in the cell using different electrolytes, but the cell performance was sensitive to the amount of the electrolyte used. The pore-filling ratio (PFR), a ratio of pore filling in the components by the liquid carbonate electrolytes, was used to determine the optimum performance range. Consequently, 77% PFR demonstrated the optimum performance for both electrolytes. Thus, the MCFC had a permissible but narrow optimum performance range. The remaining amounts of electrolyte in the cells were determined using the weight reduction ratio (WRR) method after several hours of cell operation. The WRR used the relationship between the initial loaded amount of electrolyte and weight reduction of components in 10 wt% acetic acid. The relationships were linear and identical between the two electrolyte species.

Stress Behavior Analysis of O-rings and Packing for a LPG Filling Nozzle (LPG 충전노즐용 O-링과 패킹의 응력거동해석에 관한 연구)

  • Kim, Chung-Kyun
    • Tribology and Lubricants
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    • v.22 no.1
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    • pp.20-25
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    • 2006
  • The stress behavior analysis of a-rings and packing for a LPG filling unit has been presented using a finite element analysis technique by non-linear MSC/MARC program. The sealing performance and endurance of a-rings and packing are affected by working conditions such as filling pressure, friction coefficient, compression ratio, and material properties. The elastomeric polymers of O-rings and packing are nitrile butadiene rubber (NBR) and polytetrafluoroethylene (PTFE), which are selected as proper materials of a-rings and packing based on the stress analysis results. The calculated FEM results showed that the proper material of O-ring is NBR as a secondary sealing component and the recommended material of packing is PTFE as a primary sealing unit during a LPG filling process.

An Analysis of the Job Performance in Operative Restoration by Dental Hygienists (치과위생사의 치과보존분야 직무수행 현황 분석)

  • Cho, Pyeong-Kyu
    • Journal of Korean society of Dental Hygiene
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    • v.4 no.2
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    • pp.277-291
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    • 2004
  • The purpose of this study is to analyze the dental hygienists' overall performance in operative restoration and the clinical performance in operative restoration according to dental hygienists' career and to provide basic data for establishing the appropriate range of dental hygienists' work. Subjects of this study are 339 dental hygienists working at dental clinic and hospital nationwide, selected by their working place, career, type of clinic, and location of clinical institution. The distribution of people who responded to the survey shows that 81 belong to beginner level(less than 2 years since entering clinic), 115 intermediate level(2 to 3 years since entering clinic), 81 higher level(4 to 5 years since entering clinic) and 62 advanced level(more than 6 years since their entering clinic). In terms of the types of clinical institution, 178 belong to dental clinics and 161 belong to dental hospitals. The survey used in this study are focused on perception about clinical performance in operative dentistry and adequacy of the work. Operative dentistry consists of operative restoration and endodontic therapy. The operative restoration consists of 15 categories such as patient welcoming, examination and diagnosis, planning of treatment, anesthesia, control of moisture, cavity preparation, pulp protection, matrix band application, amalgam filling, resin filling, glass ionomer cement filling, abrasive strip removal, rubber dam removal, bite check and polishing, patient education, and arrangement. The reliability was Cronbach's Alpha .9453. SPSS 10.0 for Windows was used to analyze the responses. One way ANOVA was utilized to verify the differences in the dental hygienists' job performance in operative restoration and their job performance according to career. When significant difference was found. Duncan multi comparison post hoc was done. To sum up the results of this study, patient welcoming look the first place in the operative restoration. It was followed by patient education, examination and diagnosis, introducing treatment plan, resin filling, glass ionomer cement filling, amalgam filling, bite check and polishing, anesthesia, pulp protection, control of moisture, abrasive strip removal, cavity preparation, matrix band application, rubber dam removal, and anesthesia. In terms of the clinical performance by career, there were significant differences in 19 activities such as medical eraluation, oral examination, patient charting, intra oral readio graphs, firm developing fixing mounting, curing light gun, education of attention content after operation. Based on the results of this study, the specific range of operative restoration for dental hygienists should be focused on providing basic data for dentists' diagnosis, alleviation of fear and aching accompanied by injection and anesthesia, data providing for dentists' decision of anesthesia degree, and maximization of control of moisture.

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A Study on the Flexural Behavior according to Filling conditions of Beams Members(A Siries) Using High Performance Concrete (고유동성 콘크리트를 이용한 보부재(A시리즈)의 충전상황별 휨거동 연구)

  • 장일영;윤영수;엄주환;송재호
    • Proceedings of the Korea Concrete Institute Conference
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    • 1996.04a
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    • pp.306-311
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    • 1996
  • This paper persents the flexural behavior of high performance concrete beams having different concrete filling conditions. Three tests were conducted on full-scale beam specimens with design concrete compressive strength of 400 kg/$\textrm{cm}^2$. Different concrete filling conditions were intentionally made such that the first beam specimen was soundly cast to obtain the perfect concrete filling condition. Second beam specimen was cast in such a way that up to the longitudinal tensile reinforcement from the top, good concrete was filled while poor concrete was poured for the bottom part to simulate the poor workamanship, workability and unsatisfactory compaction. Third beam specimens was cast in such a way that up to the neutral axis of the beam section from the top, good concrete was filled while so did for the bottom part as the second beam specimen. The test results were analyzed in terms of load-displacement response, formation of crack, crack width, crack spacing and shift of neutral axis. An evaluation of the ductile response fo three different beam specimens was made in combination with the ultimate load accoding to the three different concrete filling conditions.

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Flowing Ability and Mechanical Properties of Polypropylene Fiber Reinforced High Performance Concrete

  • Kim, Young-Ik;Sung, Chan-Yong
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.45 no.7
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    • pp.27-37
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    • 2003
  • This study was performed to examine the flowing ability and filling ability of polypropylene fiber reinforced high performance concrete. The slump flow was decreased with increasing the polypropylene fiber content, rapidly. At the box-type filling ability, the difference of box height was increased with increasing the fiber content and the box-type passing ability was closed in fiber content 1 %. The final flowing distance of L-type was decreased with increasing the fiber content. Also, it was decreased above 0.75% of polypropylene fiber content, rapidly. The filling ability of L-type was badly showed above polypropylene fiber content 0.75%. Also, the compressive strength was decreased with increasing the fiber content, but the flexural strength was shown higher than that of the concrete without fiber. At the impact resistance, drop numbers for reaching in final fracture were increased with increasing the fiber content. Also, the drop numbers for reaching initial fracture of 1mm were increased with increasing the fiber content. At the acid resistance, the percent of original mass was decreased with increasing the fiber content.