Due to the rapid growth of electrical vehicle and portable electronics markets, huge amount of the rare earth elements (REEs) and lithium have been required for the manufacturers globally. Moreover, after life time of the battery pass, the waste batteries containing valuable metal resources should be recycled due to competitions between the countries who manufacturing the batteries. Therefore, the REEs and lithium recoveries from the e-waste and wastewaters become issue recently. However, the commercialized technology for the valuable metal recovery is limited. In this study, the uses of the REEs and other valuable metal resources such as lithium, uranium, and gold and there recoverying methods according to the different water conditions were investigated and summarized. Moreover, the possible expectations and suggestions for the future application of the valuable resource recovery were conducted as a review.

Indoor air quality management is essential for a healthy life. However, it is difficult to perceive, detect, and monitor the level of indoor air pollution and this means that it is possible to be exposed to more pollution indoors than outdoors. In this study, in order to derive effective indoor air quality management measures, public perceptions and behavioral characteristics regarding indoor particulate matter and air quality management methods were investigated through a survey of 1,000 people. Based on the survey, it was found that most of the respondents had a negative perception of the indoor air quality of their residence, and natural ventilation was the most used method for indoor air quality management. Although the frequency of use of air quality management devices such as air purifiers and mechanical ventilation systems was relatively low, their effect regarding air quality management was positively perceived. In particular, the results of survey indicated that respondents of families which included members with fragile health engaged in more active behavior regarding in indoor air quality management than those respondents whose family members had no health issues and that the former have used air quality management devices more frequently. Therefore, it is necessary to develop proper guidelines to encourage more people to actively participate in improving indoor air quality.

Pressure retarded osmosis (PRO) process is one of membrane processes for harvesting renewable energy by using salinity difference between feed and draw solutions. Power is generated by permeation flux multiplied by hydraulic pressure in draw side. Membrane fouling phenomena in PRO process is presumed to be less sever, but it is inevitable. Membrane fouling in PRO process decreases water permeation through membrane, resulting in significant power production decline. This study intended to investigate the effect of hydraulic pressure in PRO process on alginate induced organic fouling as high and low hydraulic pressures (6.5 bar and 12 bar) were applied for 24 h under the same initial water flux. In addition, organic fouling in draw side from the presence of foulant (sodium alginate) in draw solution was examined. As major results, hydraulic pressure was found to be not a significant factor affecting in PRO organic fouling as long as the same initial water flux is maintained, inidicating that operating PRO process with high hydraulic pressure for efficient energy harvesting will not cause severe organic fouling. In addition, flux decline was negligible from the presence of organic foulant in draw side.

The Earth is exposed to constant outflow of the solar wind from the outer layers of the Sun, and violent transient events taking place from active regions increase the energy flux of both radiation and particles leaving the Sun. Thus the space surrounding the Earth is a highly dynamic environment that responds sensitively to changes in radiation, particles and magnetic field arriving from the Sun. Nowadays, it becomes increasingly important to understand how the physical system of Earth-space works and how the space around the Earth connects to interplanetary space. In the present paper we describe how explosive solar events, such as CME(Coronal Mass Ejection) and flares affect the Earth-space environment and how the space weather reacts to them. Practical consequences are presented to demonstrate why a broader view of Earth's environment is greatly needed to cope with modern day's inhabitation problem in a rapidly developing space age.

The size of fine structures in the quiescent prominence that appeared on August 16, 1992 has been estimated using power spectra generated from intensity variations of Ha images of the lower part of the prominence, which were taken with a G1 CCD camera attached to 25cm coronagraph at Norikura Coronal Station in Japan. The lower part of the prominence has shown a distinct intensity variation with optical thickness of τ=1~5. Our analysis yields a mean size of fine structures ranging from 350 km to 1,000 km, in good agreement with Hirayama(1985) and Zirker & Koutchmy(1989, 1991).

To study kinematics of solar prominences, we have made Ha spectrographic study of an eruptive prominence which appeared on the 27th of August, 1992 with a position angle of 270 deg. The observation was carried out by a Littrow type spectrograph and a G1 CCD camera attached to the 25cm coronagraph at Norikura Coronal Station. In taking the spectral data the slit was placed in parallel to the solar limb at 7 different heights, each being separated by 5 arcsec with a time step of 30 sec. The observed eruptive prominence shows a wide range of line of sight Doppler velocity, spanning from Vdopp=−17.5km/stoVdopp=58.2km/s Vdopp=−17.5km/stoVdopp=58.2km/s . It is also found that the velocity increases with height at the rate of ΔV=0.86km/s/arcsec ΔV=0.86km/s/arcsec .

A quantitative analysis has been made to estimate the horizontal variation of physical parameters in a loop type active prominence by analyzing Call H&K and Hε… Hε… spectra taken from such an active prominence (appeared on May 23, 1981 with position angle 251 degree) with Littrow type spectrograph attached to 25cm coronagraph at Norikura Coronal Station of National Astronomical Observatory of Japan. The spectral resolution is 1.12A/mm and the spatial resolution is 25'/mm for Call H&K lines. The present study shows that the turbulent velocity ranges from 10km/s to 20 km/s in the loop prominence, which are in good agreement with those of Hirayama (1989). It is also found that the temperature of the loop prominence is higher than that of quiescent prominences(\~8,000K) (\~8,000K) by about 4,000 K, whose temperature deviation seems very high.

스펙트럼선의 선폭증대 현상을 방출영역 내 기체입자들이 열운동에 의한 단순 도플러 효과로 가정하여 중심에서 어느 한쪽으로 심하게 치우친 스펙트럼 선윤곽를 해석한다. 본 연구에서는 태양활동영역에서 흔히 관측되는 좌우 비대칭의 선윤곽을 서로 다른 가우스속도분포의 기체성분들이 시선방향으로 중첩된 결과라 해석하고, 최소자승법을 이용한 비선형 선윤곽 맞춤질에 의해 스펙트럼 방출영역에서 떨어져 나가는 기채들의 온도 및 분출속도에 관련된 도플러선폭과 도플러이동량을 구하였다.

20cm 태양망원경이 소백산 천문대에서 대덕 천문우주과학연구소로 이전 설치된 후, 1987년 6월 19일 부터 1990년 11월 30일까지 흑점관측을 수행하여 343개의 흑점관측자료를 얻었다. 본 관측기간중 일일 평균 흑점상대수는 83.4로, 매일 평균 5개의 흑점군과 30개의 흑점이 관측되었다. 관측된 월평균 흑점상대수를 분석한 결과에 의하면 1986년 9월에 시작한 제22 태양활동 주기의 극대기는 1989년 9월경으로 밝혀졌다. 국제 흑점 상대수와 비교 가능한 292개의 관측 자료를 사용하여 대덕 태양망원경의 규격화 상수 K를 결정하였으며, 그 간은 소백산 천문대의 규격화 산수 0.87보다 큰 1.08로 밝혀진다.