토양세척에 의한 오염토양의 중금속(Cu, Zn, Pb) 제거에 관한 연구

김명진,Kim, Myoung-Jin 대한자원환경지질학회 2013 자원환경지질 Vol.46 No.6

본 연구에서는 Cu, Zn, Pb 총함량이 각각 최고 3350, 1220, 2240 mg/kg에 이를 정도로 높은 오염토양을 토양세척에 의해 처리하여 해당 중금속을 제거하였다. 중금속 제거효율에 영향을 미치는 중요 인자인 세척제의 종류와 농도, 세척시간, 오염토양과 세척제의 혼합비, 교반속도 등의 최적조건을 도출하였다. 세 가지 중금속을 효과적으로 제거하는 최적 세척제는 50 mM 염산, 세척시간은 30분, 오염토양과 세척제의 혼합비는 1:30 (g/mL)이었으며, 교반속도는 중금속 제거효율에 영향을 미치지 않았다. 세척제인 염산을 재사용하면 중금속 제거효율이 감소했고, 연속적으로 재사용하면 중금속이 토양에 재흡착되었다. In this study, heavy metals are removed by soil washing from soils contaminated with Cu, Zn, and Pb, whose maximum concentrations are up to 3350, 1220, and 2240 mg/kg, respectively. Through various soil washing experiments, the optimum conditions, including type and concentration of washing reagent, washing time, mixing ratio of soil and washing reagent, and stirring speed, are derived for effective removal of the heavy metals. It is found that the most effective washing reagent and its concentration are hydrochloric acid and 50 mM, respectively. The most suitable washing time is 30 minutes and the optimal mixing ratio of soil and washing reagent is 1:30 (g/mL). The removal efficiency, on the other hand, is not affected by stirring speed. The removal efficiencies of the heavy metals decrease when washing reagent is reused. Furthermore, the heavy metals are readsorbed onto soil in case of consecutive reuse of washing reagent.

지하수에서 비소의 용해 및 분리(speciation): 리뷰

김명진,Kim Myoung-Jin 대한자원환경지질학회 2005 자원환경지질 Vol.38 No.5

본 논문은 지하수에서의 비소화학과 발생에 관한 것이다. 특히, 비소종의 물리화학적 특성, As(III)의 산화, 비소의 거동과 관련된 지화학 과정, 토양으로부터 비소의 용해, 비소함유 광물로부터 비소용출 메커니즘을 주로 다루고 있다. This review deals with arsenic chemistry and its occurrence in groundwater. Specifically, the paper gives an overview regarding chemical and physical properties of arsenic species, oxidation of As(III), geochemical processes related to the fate and transport of arsenic, arsenic leaching from soil, and mechanism of arsenic leaching from arsenic-containing minerals.

칼럼을 이용한 토양에서 As(III)와 As(V)의 흡착 및 탈착에 관한 연구

김명진,김태석,Kim, Myoung-Jin,Kim, Tae-Suk 한국지하수토양환경학회 2008 지하수토양환경 Vol.13 No.1

흡착은 비소가 토양에 축적되는 주요 과정이다. 그러므로 토양에서 비소종의 흡착 및 탈착 특성을 이해하는 것은 비소종의 거동을 예측하고 토양으로부터 비소를 제거하는 적절한 정화방법을 수립하기 위해 필수적이다. 본 연구에서는 칼럼을 이용하여 토양에서 As(III)와 As(V)의 흡착 및 탈착실험을 수행하였다. As(III)에 대한 실험은 환원환경에서, 그리고 As(V)에 대한 실험은 산화환경에서 실시했다. 실험이 진행되는 동안 대부분의 As(III)는 그 산화상태를 유지하였다. As(III)의 흡착 및 탈착속도는 As(V)보다 빨랐다. 칼럼실험에서 비소종의 흡착 및 탈착반응은 완전히 가역적은 아니었다. 또한 As(V)는 회분식실험에서보다 칼럼실험에서 더 빠르게 토양에 흡착되었다. Adsorption is a major process causing the accumulation of arsenic onto soil. Therefore, further understanding of the adsorption/desorption characteristics of arsenic species on soil is essential for predicting their fate and preparing appropriate remediation strategy to remove arsenic from soil. In this study, the column adsorption/desorption experiment has been performed with As(III) and As(V) on soil. Experiment with As(III) was conducted under reducing condition, whereas that with As(V) was under oxidizing condition. Most of As(III) was remained on the oxidation state during the experiment. The results showed that the adsorption/desorption rate of As(III) was higher than that of As(V). Adsorption and desorption of arsenic species were not completely reversible in the column experiment. It was also found that As(V) in the column experiment was adsorbed more rapidly on soil than in the batch experiment.

M-밴드 코사인변조 필터뱅크를 이용한 멀티캐리어 CDMA 시스템의 이동무선환경에서의 비트오율 성능

김명진,Kim, Myoung-Jin 대한전자공학회 1999 電子工學會論文誌, S Vol.s36 No.6

멀티캐리어(MC)-CDMA는 데이터 심볼을 주파수 영역에서 확산코드를 사용하여 여러 개의 캐리어로 전송하는 방식으로 심볼 길이가 길어서 협대역 간섭에 강인하다. 그러나 사각펄스를 사용하여 데이터 변조를 하므로 서브채녈간 신호 스펙트럼은 상당한 크기의 중첩된 부엽을 가지며, 이동무선채녈 환경에서 서브채널간 직교성이 손상될 때 캐리어간 간섭이 커지게 된다. 본 논문에서는 M-밴드 코사인변조 필터뱅크(Cosine Modulated Filter Bank: CMFB)에 의하여 서브채널의 스펙트럼을 제한하는 멀티캐리어 CDMA 시스템을 제안하였다. CMFB 기반의 MC-CDMA에서는 심볼 길이보다 긴 임펄스 응답을 가진 코사인변조 필터뱅크를 사용하여 부엽의 크기를 제안하는데, 이러한 스펙트럼 제한 특성은 멀티패스 페이딩과 같은 채널의 열화에 대하여 강인함을 보이고 있다. 제안된 CMFB 기반의 MC-CDMA 시스템에 대하여 이동통신 채널에서의 비트오율 성능을 모의실험을 통하여 분석하였다. Multi-carrier CDMA is a transmission scheme where data symbols are spread in the frequency domain with a spread code then transmitted using multiple carriers. It is robust against narrowband interference because of its long symbol duration. However, due to large sidebands of the rectangular window frequency response, subchannels spectrally overlap with neighboring subchannels, which leads to substantial intercarrier interference in a dispersive channel. In this paper, we consider a mult-carrier CDMA system where subchannel spectral containment is achiveved by M-band cosine modulated filter bank (CMFB). In CMFB based MC-CDMA, subchannel spectral containment is achieved using the filter bank of longer impulse response than that of conventional discrete Fourier transform (DFT) filter bank. We show that spectral containment feature of the CMFB based fading channel is analyzed using computer simulations.

상악동저 점막 거상술을 이용한 인공치아 임프란트 동시 식립술 후 예후에 관한 임상적 연구

김명진(Myung Jin Kim),김태영(Tae Young Kim),황경균(Kyung Gyun Hwang),유상진(Sang Jin Yu),명훈(Hoon Myoung),김수경(Soo Kyung Kim),김종원(Jong Won Kim),김규식(Kyoo Sik Kim) 대한구강악안면외과학회 2000 대한구강악안면외과학회지 Vol.26 No.6

In cases of severe alveolar bony resorption in the edentulous posterior maxillae, implant placement is limited anatomically due to maxillary sinus. If the ridge is atrophic, the various bone grafting methods are required for the ridge augmentation. But the result of the onlay grafting procedure is not always promising. On the posterior maxilla, maxillary sinus mucosa lifting and bone grafting into the sinus floor, subantral augmentation(SA) technique are recommended. Various SA procedures have been developed for implant installation. We perfer to simultaneous block bone graft and implant installation through the residual alveolar ridge into the grafted block bone to fix the grafted bone and to gain the primary stability of the installed fixture. When a sagittal skeletal discrepancy in present due to the severe alveolar bony resorption of the maxilla, the advancement of the maxilla by Le Fort I osteotomy simultaneously with installation of implant fixtures combined with sinus lifting and interpositional bone graft procedure can be indicated. We applied various SA techniques for implant installtion to the 46 edentulous posterior maxillae, and total 154 implants were installed at our department from 1992 to 1999. Various SA techniques were classified in detail and the indications of each techniques were discussed. The changes of residual bony height following SA procedure were studied. The results were as follows. 1. The SA procedure combined with bone graft and simultaneous fixture installation were performed in 41 cases, 126 fixtures were installed and 5 fixtures were removed out of them. Le Fort I osteotomy procedure combined with sinus lifting and interpositional bone graft simultaneous with fixture installation were performed in 5 cases. Total 28 fixtures were installed and 2 fixtures were removed so far. 2. Autogenous block bone graft into sinus floor were performed in 35 cases, autogenous particulated marrow cancellous bone(PMCB) graft in 9 cases, and demineralized human bone powder in 2 cases. The donor site for bone graft were anterior iliac bone in 39 cases, posterior iliac bone in 3 cases and mandibular symphysis in 1 case and mandibular ramus in 1 case. 3. In 9 cases with which SA procedure had been performed with the block bone graft, the change of pre- and postoperative residual bony height were measured using MPR(multiplanar reformatted)-CT. The mean residual bony height was 8.0mm preoperatively, 20.2mm at 6 months following up operation and we gained average 12.2mm alveolar bony height. So, we can recommend this one-stage subantral augmentation and fixture installation technique as a time conserving, safe and useful method for compromised posterior edentulous maxilla.

토양에서의 비소흡착

김명진(Myoung Jin Kim),안규홍(Kyu Hong Ahn),정예진(Ye Jin Jung) 大韓環境工學會 2003 대한환경공학회지 Vol.25 No.4

폐광산 광미에서의 비소 분리(speciation) 및 중금속 특성에 관한 연구

김명진(Myoung Jin Kim),안규홍(Kyu Hong Ahn),정예진(Ye Jin Jung) 大韓環境工學會 2001 대한환경공학회지 Vol.23 No.10

시간선택적 페이딩 환경에서 멀티캐리어-CDMA 시스템의 서브캐리어간 간섭

김명진(Myoung Jin Kim),김성필(Sung Pil Kim),하경민(Kyung Min Ha) 대한전자공학회 2000 대한전자공학회 학술대회 Vol.2000 No.6

Detection of Narrowband Signal with Unknown Carrier Frequency Based on Time Averaged Bandpass FFT Power Spectra

Myoung Jin Kim(김명진),Juhyun Han(한주현) 한국통신학회 2001 한국통신학회 학술대회 및 강연회 Vol.2001 No.4

실시간 H.264/AVC를 위한 적응적인 프레임 단위 비트율 제어 기법

김명진(Myoung-Jin Kim),김경환(Kyoung-Hwan Kim),홍민철(Min-Cheol Hong) 한국방송·미디어공학회 2008 방송공학회논문지 Vol.13 No.6

In this paper, we propose an adaptive rate control in frame-level for real-time H.264/AVC. For given QP, bits according to video characteristics, and current frame is close correlation between the adjacent frames. Using the statistical characteristic, we obtain change of occurrence bit about QP to apply the bit amount by QP from the video characteristic and applied in the estimated bit amount of the current frame. In addition, we use weight with QP and occurrence bit amount that is statistical information of encoded previous frames. Simulation results show that the proposed rate control scheme achieves time saving of more than 99% over JM 12.1 rate control algorithm. Nevertheless, PSNR and bit rate were almost same as the performances of JM.