• Title/Summary/Keyword: Zs

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Removal Characteristics of Heavy Metals in Acid Wastewater by Ceramics Using Natural Zeolite and Converter Slag (천연제올라이트와 제강전로슬래그를 이용한 세라믹 소재에 의한 산성폐수 내 중금속의 제거특성)

  • Kim, Dong-Hee;Yim, Soo-Bin
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.4
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    • pp.239-246
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    • 2012
  • This study was performed to investigate the removal characteristics and mechanism of heavy metals using pellet-type ceramics(ZS ceramics), in which natural zeolite was mixed and calcined with converter slag. The optimal calcination temperature range was measured to be $600{\sim}800^{\circ}C$. The calcination time had little effect on the removal of heavy metal in acid wastewater. The adequate dose of ceramics was shown to be 2~5% for removal of heavy metals in acid wastewater. The maximum removal capacity of ZS ceramics for heavy metals were observed to be Al 84.7 mg/g, Cd 37.3 mg/g, Cr 81.7 mg/g, Cu 55.6 mg/g, Fe 57.2 mg/g, Mn 32.1 mg/g, Ni 38.0 mg/g, Pb 71.6 mg/g, Zn 46.3 mg/g. The pH played a pivotal role in the removal of heavy metals by ZS ceramics. The analysis results of mechanism exhibited that the ZS ceramics could act as a multi-functional ceramics for removal of heavy metals in acid wastewater by adsorption, ion-exchange, or precipitation.

A Study on the Accuracy of Scan by the Standard Model Deformation Depending on the Hand Scanning Method (핸드스캐닝 작업 방법에 따라 표준 모델 변형이 작업 정밀도에 미치는 정밀스캔에 관한 연구)

  • Shin, Seong-Hun;Jang, Seong-Ho;Song, Joon-Ki;Park, Kwang-Sig;Lee, Hee-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.197-202
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    • 2018
  • This study was conducted to evaluate the distortion and data accuracy that may occur depending on the methods employed by the oral scanner (intra-oral scanner). Deseutap 3D models employing a plaster model used clinically as a scanner to create a standard scan data using the same model, separated by oral scanners in three different ways (AS Group, ZS group, OS group) How to scan each 5 times made the scan data for each group, it shows the 0.121 mm, 0.172 mm AS group, OS group 0.423 mm accuracy in ZS group. The ZS group showed the highest accuracy, with maximum error values of 0.113 mm, 0.169 mm and 0.246 being observed for the ZS, AS and OS group, respectively. The three scanning methods showed a clear differences in accuracy and reproducibility and also appeared to be meaningful in clinical practice.

Effect of the New Surface Treatment Method of Zirconia on the Shear Bond Strength with Resin Cement (지르코니아의 새로운 표면처리 방법이 레진 시멘트와의 전단결합강도에 미치는 영향)

  • Cho, Won-Tak;Bae, Ji-Hyeon;Choi, Jae-Won
    • Journal of Digital Convergence
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    • v.19 no.3
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    • pp.245-251
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    • 2021
  • This study was to investigate the effect of the new surface treatment method of zirconia on the shear bond strength with resin cement. The zirconia specimens were classified according to the surface treatment. CON: non-treatment, HF: 10 minutes exposure to 9% HF, ZS15: Apply 15% ZrO2 slurry, ZS30: Apply 30% ZrO2 slurry, ZS50: Apply 50% ZrO2 slurry. The resin cement was layered on the surface treated zirconia, and the shear bond strength between the zirconia and the resin cement was measured after thermo-cycling. The statistical methods for shear bond strength were Kruskal-Wallis test, Mann-Whitney U test, and Bonferroni correction(α=.05/10=.005). ZS15, ZS30, and ZS50 groups treated with zirconia slurry showed higher shear bond strength than CON and HF groups(p<.05/10=.005). Within the limits of this study, the surface treatment using zirconia slurry increased the shear bond strength with resin cement. The new surface treatment method complements and improves the limitations of the adhesion of zirconia, so that various clinical applications of zirconia can be expected.

A Comparison of Spinosin Content in Zizyphi Semen and Its Processed Products by Roasting (산조인의 수치에 따른 Spinosin 함량 비교)

  • Seo, Chang-Seob;Kim, Jung-Hoon;Shin, Hyeun-Kyoo;Kim, Byoung-Soo
    • Korean Journal of Pharmacognosy
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    • v.47 no.4
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    • pp.360-365
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    • 2016
  • The aim of this study was to compare the amount of spinosin in the 70% ethanol extracts of non-processed Zizyphi Semem (ZS) and processed ZS by roasting using a high-performance liquid chromatography equipped with photodiode array detector. Separation of the spinosin was used $SunFire^{TM}$ $C_{18}$ analytical column ($5{\mu}m$, $4.6{\times}150mm$) using two mobile phase consisting of distilled water and acetonitrile, both with 1.0% (v/v) acetic acid. The flow rate was 1.0 mL/min and injection volume was $10{\mu}L$. Calibration curve of the spinosin was y = 22339.45x+483.99 in tested concentration range ($1.28-20.00{\mu}g/mL$) and correlation coefficient was 1.0000. In non-processed ZS sample, the amount of the spinosin was 0.94 m/g, while, the amount of the marker compound in processed ZS samples were 0.66-1.10 mg/g.

A ZS Synchronization Algorithm for the Security of T1 Carrier System (T1 전송시스템 보호를 위한 ZS 동기 알고리듬)

  • 이훈재;박봉주;장병화;문상재;박영호
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.7 no.3
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    • pp.53-64
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    • 1997
  • When we apply a synchronous stream cipher to the T1 carrier system, it can occur long consecutive 0's(or 1's) sequences in the received data. In this case, it is difficult to recover receiver clock and violates a communication protocol. This paper proposes block detection and serial detection method which suppress 0's sequences of more than k( $\geq$ 2) of the stream ciphertext in the T1 carrier system. These ZS methods keep security level and solve problems of stream synchronization.

Anti-inflammatory Effect of Zeae Stigma Herbal-acupuncture at KI10 on LPS-induced Nephritis in Rats (음곡 옥미수 약침이 LPS로 유도된 흰쥐의 신장염에 미치는 영향)

  • Kim, Yang-Seob;Yim, Yun-Kyoung
    • The Journal of Korean Medicine
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    • v.34 no.3
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    • pp.25-36
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    • 2013
  • Objectives: The purpose of this study was to investigate the effects of Zeae Stigma herbal-acupuncture (ZS-HA) at KI10 (Umgok) on nephritis induced by lipopolysaccharide (LPS) in rats. Methods: Rats were assigned to five groups, normal, LPS, NP, saline and ZS-HA. Rats in NP, saline, and ZS-HA groups were treated with needle prick, saline injection, and ZS-HA respectively at KI10, three times a week. All animals except the normal group were injected intra-peritoneally with LPS to induce nephritis. RBC and WBC, neutrophils in blood, TNF-alpha, CINC-1, creatinine in serum, urinal volume, total protein and creatinine in urine, and renal MPO were analyzed. Results: Needle prick at KI10 significantly reduced WBC in blood and CINC-1 in serum of LPS-stimulated rats. Saline injection at KI10 significantly reduced TNF-${\alpha}$ in serum and total protein in urine of LPS-stimulated rats. ZS-HA at KI10 significantly increased RBC in blood, and significantly reduced neutrophils in blood, TNF-${\alpha}$ in serum, and total protein in urine of LPS-stimulated rats. Conclusions: According to these results, it is postulated that ZS-HA at KI10 has anti-inflammatory and renal-protective effects on LPS-induced nephritis in rats, and both acupoint KI10 and herb Zeae Stigma made contributions to this effect. Further studies on the interaction between acupoint KI10 and herb Zeae Stigma may be needed.

A Microscopic Study on Treatment Mechanism of Acid Mine Drainage by Porous Zeolite-slag Ceramics Packed in a Column Reactor System (컬럼반응조 내 충진된 다공성 zeolite-slag 세라믹에 의한 산성광산배수의 처리기작에 대한 미세분석 연구)

  • Yim, Soo-Bin
    • Journal of Korean Society of Water Science and Technology
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    • v.26 no.6
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    • pp.13-26
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    • 2018
  • This research was conducted to elucidate the removal mechanism of heavy metals and sulfate ion from acid mine drainage(AMD) by porous zeolite-slag ceramics (ZS ceramics) packed in a column reactor system. The average removal efficiencies of heavy metals and sulfate ion from AMD by the 1:3(Z:S) porous ZS ceramics in the column reactor under the HRT condition of 24 hours were Al 97.5%, As 98.8%, Cd 86.1%, Cu 96.2%, Fe 99.7%, Mn 64.1%, Pb 97.2%, Zn 66.7%, and $SO_4{^{2-}}$ 76.0% during 121 days of operation time. The XRD analysis showed that the ferric iron from AMD could be removed by adsorption and/or ion-exchange on the porous ZS ceramics. In addition it was known that Al, As, Cu, Mn, and Zn could adsorb or coprecipitate on the surface of Fe precipitates such as schwertmannite, ferrihydrite, or goethite. The EDS analysis revealed that Al, Fe, and Mn, which were of relatively high concentration in the AMD, would be adsorbed and/or ion-exchanged on the porous ZS ceramics and also exhibited that Al, Cu, Fe, Mn, and Zn could be precipitated as the form of metal hydroxide or sulfate and adsorbed or coprecipitated on the surface of Fe precipitates. The microscopic results on the porous ZS ceramics and precipitated sludge in a column reactor system suggested that the heavy metals and sulfate ion from AMD would be eliminated by the multiple mechanisms of coprecipitation, adsorption, ion-exchange as well as precipitation.

Osseointegration of zirconia implant in the tibia of pigs (돼지의 경골에 식립된 지르코니아 임플란트의 골유착에 관한 연구)

  • Kim, Lee-Kyoung;Cho, In-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.3
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    • pp.190-198
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    • 2013
  • Purpose: The purposes of this study were to investigate osseointegration around zirconia implants which had machined or alumina sandblasted surface, and to compare the results with titanium implants. Materials and methods: The study was performed on the tibia of 6 pigs. Three types of implants were investigated: group T-titanium implant, group Z-machined zirconia implant, group ZS-alumina sandblasting treated zirconia implant. Zirconia implants were manufactured from yttria-stabilized tetragonal zirconia polycrystalline (Acucera Inc., Pocheon, Korea). A total of 36 implants were installed in pigs' tibias. After 1, 4 and 12 weeks of healing period, the periotest and the histomorphometric analysis were performed. The data were analyzed using one-way ANOVA and significance was assessed by the Scheffe test (${\alpha}=.05$). Results: In the measurement of surface roughness, highest Ra value was measured in group T with significant difference. No significant differences were found among groups regarding Periotest values. After 1 week, in comparison of bone to implant contact (BIC), group Z showed higher value with significant difference. In comparison of bone area (BA), group T and group Z showed higher value with significant difference than group ZS. After 4 weeks, in comparison of BIC, group T showed higher value with significant difference. Comparison of BA showed no significant difference among each implant. After 12 weeks, the highest mean BIC values were found in group T with significant difference. Group ZS showed higher BIC value with significant difference than group Z. In comparison of BA, group T and group ZS showed higher value with significant difference than group Z. Conclusion: Zirconia implant showed low levels of osseointegration in this experiment. Modification of surface structure should be taken into consideration in designing zirconia implants to improve the success rate.

Logic Implementation of HDB3 Codec (HDB3 Codec의 로직구현)

  • Eom, Joon;Kim, Young-Kil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.2
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    • pp.369-374
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    • 2018
  • The Line Code is a code used for data transmission and is a coding method used to prevent loss of data between transmitter and receiver. There are various kinds of line code such as B3ZS, HDB3, B8ZS, and HDB3 code is used in the tactical communication networks of Korea. In this paper, we implement the HDB3 Codec that is used in tactical communication networks in order to eliminate the risk factors for component discontinuance and to shorten development period and ensure reliability. Also it is confirmed that it can be implement by minimizing the amount of logic usage so that it can be used unrestrictedly in systems using FPGA and the implemented HDB3 Codec is simulated to confirm that it is equivalent to the performance of HDB3 Codec IC.

Obtaining 1-pixel Width Line Using an Enhanced Parallel Thinning Algorithm (병렬 세선화 알고리즘을 이용한 1-화소 굵기의 선 구하기)

  • Kwon, Jun-Sik
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.1
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    • pp.1-6
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    • 2009
  • A Thinning algorithm is a very Important factor in order to recognize the character, figure, and drawing. Until comparatively lately, the thinning algorithm was proposed by various methods. In this paper, we ascertain the point at issue of ZS(Zhang and Suen), LW(Lu and Wang) and WHF(Wang, Hui and Fleming) algorithms that are the parallel thinning algorithms. The parallel thinning algorithm means the first processing doesn't have to influence to the second processing. ZS algorithm has a problem which loses pixels in slanting lines and LW algorithm doesn't have one pixel width in slanting lines. So I propose an advanced parallel thinning algorithm that connects the pixels each other and preserve the end point.