• Title/Summary/Keyword: Compression and Recovery

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A study on the steam boiler with high compression waste heat recovery system (고압축 폐열회수장치를 구비한 증기보일러에 관한 연구)

  • HAN, Kyu-il;CHO, Dong-Hyun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.3
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    • pp.302-307
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    • 2017
  • An electric steam boiler equipped with a condensate recovery system, which stores the condensate generated after using steam in steam washers, steam cookers, steam irons, and steam cleaners in a condensate tank and supplies compressed air to the condensate tank so that the condensate is recovered to the boiler by the pressure of the compressed air, was studied. In the results of this study, the heat energy balance between the quantity of the heat generated by the non-metallic surface heating element and the quantity of the heat absorbed by the water was good in a range of ${\pm}5%$. In addition, the heat transfer rate increased in proportion to the electric power of the surface heating element heater, the waste heat energy was normally recovered by the recovery of the condensate of the steam boiler equipped with the high compression waste heat recovery system, and the recovery rate of the waste heat exhibited 23%.

Fixation of Compression Set of Heat-Compressed Wood by Steaming (수증기 처리에 의한 열압밀화목재의 압축 고정)

  • 이원희;한규성
    • Journal of the Korea Furniture Society
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    • v.11 no.1
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    • pp.85-89
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    • 2000
  • This study investigated the effect of steaming on fixation of compression set and the effect of these treatments on mechanical properties of heat-compressed wood specimens. To determine the effect of steaming after compression set, wood specimens were compressed for 100min at 180f and then steamed for 20-100min at $120^{\circ}C$. Swelling tests were used to evaluate recovery of compression set. Bending, compression, and Brinell hardness tests were carried out for evaluating mechanical properties. Compressed wood steamed for 100 min at $120^{\circ}C$ showed 1.9% recovery of set, increases in bending and compressive properties, and no hardness change. We concluded that almost complete fixation of compression set in wood can be achieved by steaming compressed wood.

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Adaptive Video Watermarking Using Half-cell Motion Vector (반화소 움직임 벡터를 이용한 적응적 비디오워터마킹)

  • Shinn Brian-B.;Kim Min-Yeong;D Khongorzul;Lee In-Sung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.7
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    • pp.1214-1221
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    • 2006
  • Header compression scheme is suggested as a solution to reduce the inefficient overhead of general packet stream data. Especially, it is shown that there are more overhead rate for real-time media stream links such as voice because of its short payload size, and it is possible to get higher bandwidth efficiency using the header compression scheme. There are two kinds of error recovery in header compression such as Periodic Header Refresh(PHR) and Header Request(HR) schemes. In this paper, we analyze the performance of these two compression recovery schemes, and some results such as the overhead rate, bandwidth gain and bandwidth efficiency(BE) are presented.

A Study on the Physical Properties of Addition Silicone Impression Materials (부가중합형실리콘인상재의 물리적 특성에 대한 연구)

  • Kim, Soo-Hwa
    • Journal of dental hygiene science
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    • v.6 no.4
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    • pp.231-235
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    • 2006
  • This study evaluated the properties of polyvinylsiloxane impression materials: Strain-in-compression, Elastic recovery, Consistency, and Wettability. Four polyvinylsiloxane impression materials(Examixfine, GC, Japan; Aquasilultra, Dentsply, USA; Extrude, Kerr, USA; Perfect-F, Handae, Korea) were used in this study. The measured data were analyzed with SPSSWIN 12.0 program. The results were as follows : 1. The strain-in-compression values showed that Extrude had the lowest value, 4.86% and Examixfine had the highest value, 6.78%. Significant difference between Examixfine and Perfect-F was not found but the other groups had significant differences(p = 0.000). 2. In the elastic recovery test, Extrude had the highest, 99.83% and Perfect-F had the lowest, 96.54%. There is no significant difference between Examixfine and Aquasilultra. The other impression material groups showed significant differences(p = 0.000). 3. The measurement of consistency results that the diameter of Examixfine was the largest, 45.12mm and one of Perfect-F was the smallest, 40.28 mm. No differences were shown between Examixfine and Aquasilultra and between Extrude and Perfect-F(p = 0.001). 4. Aquasilultra had a better hydrophilicity($47.85^{\circ}$) than other materials. Perfect-F had a larger contact angle($94.89^{\circ}$) and was hydrophobic. There were significant differences between groups(p = 0.000). 5. As for correlation among the test types, contact angle correlated with strain-in-compression, elstic recovery and consistency. The strain-in-compression had correlation to contact angle and elastic recovery. The elastic recovery correlated with contact angle and strain-in-compression. And the consistency had correlation to contact angle.

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Non-Iterative Threshold based Recovery Algorithm (NITRA) for Compressively Sensed Images and Videos

  • Poovathy, J. Florence Gnana;Radha, S.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.4160-4176
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    • 2015
  • Data compression like image and video compression has come a long way since the introduction of Compressive Sensing (CS) which compresses sparse signals such as images, videos etc. to very few samples i.e. M < N measurements. At the receiver end, a robust and efficient recovery algorithm estimates the original image or video. Many prominent algorithms solve least squares problem (LSP) iteratively in order to reconstruct the signal hence consuming more processing time. In this paper non-iterative threshold based recovery algorithm (NITRA) is proposed for the recovery of images and videos without solving LSP, claiming reduced complexity and better reconstruction quality. The elapsed time for images and videos using NITRA is in ㎲ range which is 100 times less than other existing algorithms. The peak signal to noise ratio (PSNR) is above 30 dB, structural similarity (SSIM) and structural content (SC) are of 99%.

Mechanical Properties of Rice Plants Under the Transverse Loading -Creep and Recovery Behavior- (측방향하중(側方向荷重)에 의한 벼줄기의 역학적특성(力學的特性)에 관한 연구(硏究)(II) -크리이프 및 회복 거동-)

  • Huh, Yun Kun
    • Korean Journal of Agricultural Science
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    • v.23 no.2
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    • pp.233-241
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    • 1996
  • The mechanical properties of biological materials depend on numerous factors. The majority of these relationships are still unknown today, especially with regard to their quantitative characteristics. The reason is that biological materials constitute biomechanical systems of very complex construction, whose behavior cannot be characterized by simple physical constants, as for example can that of engineering materials. The objectives of this investigation were to determine the compression creep and recovery properties of rice stalks at various levels of applied load The compression creep and recovery behavior of the rice stalk could be predicted precisely by rheological model which approached closely to the measured values. But the coefficients of the Burgers recovery model were different from those of the creep model. The Steady state creep behavior occurred at the higher level of force and the logarithmic creep behavior occurred at the lower level of force. The mechanical model being expected the creep behavior in relation with the level of applied load, which was well explained that the rice stalk might be visco-elastic material.

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Convalescence from Saturday Night Palsy (요골신경 압박마비의 회복)

  • Rhee, Seung-Yong;Han, Soo-Hong;Lee, Soon-Chul;Lee, In-Sung;Kim, Jin-Woo
    • Archives of Reconstructive Microsurgery
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    • v.21 no.2
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    • pp.81-85
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    • 2012
  • Purpose: Saturday night palsy is a transient form of nerve palsy that occurs after a prolonged period of direct pressure on the course of radial nerve by one's own or spouse's head. Although commonly encountered, there have been only few studies concerning its convalescence. The purpose of this study is to predict the prognosis of Saturday night palsy based on the causes, time to recovery and degree of recovery. Materials and Methods: Retrospective study of 20 patients who were diagnosed compression radial nerve palsy was performed. The average age was 36.7 years old and the mean follow-up period was 19.6 months. We investigated sleeping hours as an indirect measure of nerve compression time, recovery of wrist and finger extension, DASH score on the monthly based follow up. Results: The mean sleeping hours was 5.8 hours and all patients showed full recovery of wrist and fingers extension with the mean duration of symptom for 3.2 months. DASH score was an average 1.53 at the last follow up and we found no statistical significance between the time to recovery and the sleeping hours. Conclusion: Complete natural recovery can be expected in compression radial nerve palsy in this study without correlation with sleeping time. Accurate diagnosis is important in order to avoid unnecessary therapeutic intervention and further study should be accomplished for clarifying the related prognostic factors in larger scale of the cases.

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Quality Improvement of Oil Palm Trunk Properties by Close System Compression Method

  • Hartono, Rudi;Wahyudi, Imam;Febrianto, Fauzi;Dwianto, Wahyu;Hidayat, Wahyu;Jang, Jae-Hyuk;Lee, Seung-Hwan;Park, Se-Hwi;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.172-183
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    • 2016
  • Densification of the inner part of oil palm trunk (OPT) by the close system compression (CSC) method was performed in this study. The effects of the compression temperature and time on the anatomical, physical and mechanical properties of OPT were evaluated. The inner part of OPT with an initial average density of $0.3g/cm^3$ was used as samples. Oven-dried samples were immersed in water and vacuumed until fully saturated and then compressed by CSC at 120, 140, 160 or $180^{\circ}C$ for 10, 20, 30 or 40 min. The anatomical characteristics of transverse and radial sections before and after compression were compared by optical microscopy. The physical and mechanical properties, including the density, recovery of set (RS), modulus of elasticity (MOE), modulus of rupture (MOR), and compression parallel to grain were examined. It was observed that the anatomical characteristic of the inner part of OPT (i.e., vascular bundles, vessels, and parenchyma tissue) became flattened, fractured, and collapsed after compression by CSC. The RS decreased with increasing compression temperature and time. The lower RS indicated high dimensional stability. The physical and mechanical properties (i.e., density, MOR, MOE, and compressive strength) of the inner part of OPT increased with increasing compression temperature and time. Compression by the CSC method at $160^{\circ}C$ for 40 min was the optimum treatment.

INFLUENCE OF SODIUM ALGINATE CONTENTS ON THE STRAIN IN COMPRESSION, ELASTIC RECOVERY, AND COMPRESSIVE STRENGTH OF EXPERIMENTAL ALGINATE IMPRESSION MATERIALS (알긴산소오다 함량이 실험적 알지네이트 인상재의 압축변형율, 탄성회복율 및 압축강도에 미치는 영향)

  • Lee Yong-Sik;Choi Boo-Byung;Lee Sung-Bok
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.2
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    • pp.243-257
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    • 2003
  • The purpose of this study was to search the influences of the increase of the contents of sodium alginate in the experimental alginates on the some mechanical properties. 3 commercial alginates were selected for the purpose of comparison of the results of experiments. 7 experimental alginates were manufactured with the rise of contents of sodium alginate from 8.8% to 18.3% with the decrease of contents of diatomaceous earth and with the constant contents of calcium sulfate 12.5%. sodium phosphate 2.2%, zinc fluoride 2.0%. Splitable metal mold with 12.5mm diameter and 20.0mm height was filled with mixed alginate to prepare the cylinder shaped specimens. Strain in compression, elastic recovery, compressive strength were tested using the ISO specification number 1563, alginate impression material. Experimental groups were 7, and 10 specimens were used for each test items and each groups. Following results were obtained ; 1. Strain in compression was decreased with the increase of sodium alginate contents (p=0.0077, r2 = 0.6302). 2. Elastic recovery was decreased with the increase of sodium alginate contents but was not significant(p=0.0639, r2=0.7449). 3. Compressive strength was increased with the increase of sodium alginate contents (p<0.0001, r2 = 0.9617). These results mean that the increase of sodium alginate contents make alginate harder but may result the increased permanent deformation.

Design and Implementation of Backup and Recovery System (백업 및 복원 시스템의 설계 및 구현)

  • Lee, Moon-Ku
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.1133-1136
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    • 2005
  • The proposed high-speed backup and recovery system is a high performance backup software based on multi streaming I/O and high speed/high compression technology, and can realize an increase efficiency of backup volume without any increase of backup H/W equipments since it provides a high performance in data backup of a user and executes high compression very fast. Particularly, it minimizes consumption of network band width through a development of algorism for high compression in connection with backup equipments in a large-scaled system environment, is automated when it is recovered due to danger and troubles, and allows users to conveniently access in various ways since GUI and CLI for execution and management are all provided.

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