Projections of summertime ozone concentration over East Asia under multiple IPCC SRES emission scenarios

Lee, Jae-Bum,Cha, Jun-Seok,Hong, Sung-Chul,Choi, Jin-Young,Myoung, Ji-Su,Park, Rokjin J.,Woo, Jung-Hun,Ho, Changhoi,Han, Jin-Seok,Song, Chang-Keun Elsevier 2015 Atmospheric environment Vol.106 No.-

<P><B>Abstract</B></P> <P>We have developed the Integrated Climate and Air Quality Modeling System (ICAMS) through the one-way nesting of global–regional models to examine the changes in the surface ozone concentrations over East Asia under future climate scenarios. Model simulations have been conducted for the present period of 1996–2005 to evaluate the performance of ICAMS. The simulated surface ozone concentrations reproduced the observed monthly mean concentrations at sites in East Asia with high R<SUP>2</SUP> values (0.4–0.9), indicating a successful simulation to capture both spatial and temporal variability. We then performed several model simulations with the six IPCC SRES scenarios (A2, A1B, A1FI, A1T, B1, and B2) for the next three periods, 2016–2025 (the 2020s), 2046–2055 (the 2050s), and 2091–2100 (the 2090s). The model results show that the projected changes of the annual daily mean maximum eight-hour (DM8H) surface ozone concentrations in summertime for East Asia are in the range of 2–8 ppb, −3 to 8 ppb, and −7 to 9 ppb for the 2020s, the 2050s, and the 2090s, respectively, and are primarily determined based on the emission changes of NO<SUB>x</SUB> and NMVOC. The maximum increases in the annual DM8H surface ozone and high-ozone events occur in the 2020s for all scenarios except for A2, implying that the air quality over East Asia is likely to get worse in the near future period (the 2020s) than in the far future periods (the 2050s and the 2090s). The changes in the future environment based on IPCC SRES scenarios would also influence the change in the occurrences of high-concentrations events more greatly than that of the annual DM8H surface ozone concentrations. Sensitivity simulations show that the emissions increase is the key factor in determining future regional surface ozone concentrations in the case of a developing country, China, whereas a developed country, Japan would be influenced more greatly by effects of the regional climate change than the increase in emissions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Change in ozone level is determined by the combination of NO<SUB>x</SUB> and NMVOC emissions. </LI> <LI> Ozone level over East Asia would get worse in the near future (the 2020s) than far future. </LI> <LI> A high-concentration event generally increases and more frequently occurs in the future. </LI> <LI> Change in ozone air quality in a developing country depends more on emissions change. </LI> <LI> Change in ozone air quality in a developed country depends more on climate change. </LI> </UL> </P>

Diagnostic Significance of Brainstem Auditory Evoked Potentials in Microvascular Decompression of Patients with Hemifacial Spasm or Trigeminal Neuralgia

( Sang-koo Park ),( Sung-hyuk Lim ),( Chan-woo Park ),( Jin-woo Park ),( Sung-ho Chang ),( Keun-hye Park ),( Hae-ja Park ),( Ji-hye Song ),( Dong-ok Uhm ),( Ki-bong Kim ) 대한임상검사과학회 2011 대한임상검사과학회지(KJCLS) Vol.43 No.1

The purpose of this study was to analyse brainstem auditory evoked potentials (BAEP) wave change data during microvascular decompression (MVD). The nerve function of Cranial Nerve VIII is at risk during MVD. Intraoperative monitoring of BAEP can be a useful tool to decrease the danger of hearing loss. Between January and December 2009, 242 patients had MVD for hemifacial spasm (HFS) and trigeminal neuralgia (TN). Among intraoperative BAEP changes, amplitude of V-V’ was the most frequently observed during cerebellar retraction and decompression step of the MVD procedure. 138 patients (57%) had no BAEP change while 104 patients (42.98%) had BAEP change. 69 patients (28.5%) had Type A-I, 16 patients (6.6%) had Type A-II, 5 patients (2.1%) had Type B, and 13 patients (5.37%) had Type C. MVD is a surgical procedure to relieve the symptoms (e.g. pain, muscle twitching) caused by compression of a nerve by an artery or vein. During BAEP intraoperative monitoring, the surgical step is important in interpreting the changes of wave V. Several potential mechanisms of injury may affect the cochlear nerve, and complete loss of BAEP is often associated with postoperative hearing loss. Intraoperative BAEP monitoring may provide an early warning of hearing disturbance after MVD.

Effect of Changing Amniotic Fluid Osmolarity on the Li⁺ Transport Through the Membrane Surrounding Amniotic Fluid in the Rabbit

Chang. Jin-Keun,Lee. Sang-Jin,Sung. Ho-Kyung 대한생리학회 1993 대한생리학회지 Vol.27 No.1

To study the regulation of amniotic fluid volume and electrolyte concentration by the Membranes surrounding the amniotic fluid, the rate of Li⁺ disappearance from amniotic sac of expired fetuses were examined while increasing the amniotic volume and osmolarity in rabbits. After intraamniotic injection of 1 ml isosmotic saline (about 20% of the amniotic fluid volume) containing 15 mM LiCl and 0.5 g/L Censored, the time courses of Li⁺ and Censored disappearance were determined. From there the Li⁺ clearance through the extrafetal routes was estimated and compared with that obtained from living fetuses. The volume, Na⁺ concentration and osmolarity of amniotic fluid were measured and their relationships with Li⁺ disappearance were evaluated. The fellowing results were obtained: 1. The rate of disappearance from amniotic fluid of living fetuses during the first 30 minutes was strikingly higher for Li⁺ than for Censored, suggesting that extrafetal routes exist. At 60 and 90 minutes, however, the disappearance rate of Li⁺ was less than that of Censored, suggesting the possibility of Li⁺ reentry through fetal urination. 2. The disappearance of Li⁺ from the amniotic fluid of the expired fetus was substantial, although lower than that of living fetuses, throughout the experimental period. 3. The Na⁺ concentration and the osmolarity of the amniotic fluid of expired fetus measured 30 minutes after an intraamniotic injection of isoosmotic saline showed wide variation, but thereafter they changed gradually towards the normal extracellular fluid level. 4. When the amniotic fluid was iso- or hyposmolar, the rate of Li⁺ disappearance from the amniotic fluid of the expired fetuses showed little variation. However, when the amniotic fluid was hyperosmolar, the rate at 30 minutes was markedly lower than those of isosmotic or hyposmotic amniotic fluid. At 90 minutes, the rate of Li⁺ disappearance in hyperosmolar fluid reached a similar level to the rate in isosmolar fluid. 5. The intraamniotic injection of 400 mOsm/L saline solution decreased the disappearance rate of Li⁺ from expired fetuses, while the injection of mannitol into the maternal vein induced no significant change. From these results it is concluded that: 1) a significant amount of Li⁺ may leave the amniotic fluid via filtration through the membranes surrounding the amniotic fluid, 2) during hyperosmolar challenge to amniotic fluid, osmotic bulk flow might counteract the filterable loss, and 3) Li⁺ disappearance might continue even after the volume and osmolarity of the amniotic fluid have recovered to control values.

Changes of Nuclear glycoproteins in Normal and simin Virun 40-Transformed WI-38 Human Lung Fibroblasts

Choi, Seok-Keun,Lee, Sang-Ho,Chang, Hyo-Ihl Korean Society of Molecular Biology 1998 Molecules and cells Vol.8 No.6

Effect of Changing Amniotic Fluid Osmolarity on the $Li^+$ Transport Through the Membrane Surrounding Amniotic Fluid in the Rabbit

Chang, Jin-Keun,Lee, Sang-Jin,Sung, Ho-Kyung The Korean Physiological Society 1993 대한생리학회지 Vol.27 No.1

To study the regulation of amniotic fluid volume and electrolyte concentration by the Membranes surrounding the amniotic fluid, the rate of $Li^+$ disappearance from amniotic sac of expired fetuses were examined while increasing the amniotic volume and osmolarity in rabbits. After intraamniotic injection of 1 ml isosmotic saline (about 20% of the amniotic fluid volume) containing 15 mM LiCl and 0.5 g/L Censored, the time courses of $Li^+$ and Censored disappearance were determined. From there the $Li^+$ clearance through the extrafetal routes was estimated and compared with that obtained from living fetuses. The volume, $Na^+$ concentration and osmolarity of amniotic fluid were measured and their relationships with $Li^+$ disappearance were evaluated. The fellowing results were obtained: 1. The rate of disappearance from amniotic fluid of living fetuses during the first 30 minutes was strikingly higher for $Li^+$ than for Censored, suggesting that extrafetal routes exist. At 60 and 90 minutes, however, the disappearance rate of $Li^+$ was less than that of Censored, suggesting the possibility of $Li^+$ reentry through fetal urination. 2. The disappearance of $Li^+$ from the amniotic fluid of the expired fetus was substantial, although lower than that of living fetuses, throughout the experimental period. 3. The $Na^+$ concentration and the osmolarity of the amniotic fluid of expired fetus measured 30 minutes after an intraamniotic injection of isoosmotic saline showed wide variation, but thereafter they changed gradually towards the normal extracellular fluid level. 4. When the amniotic fluid was iso- or hyposmolar, the rate of $Li^+$ disappearance from the amniotic fluid of the expired fetuses showed little variation. However, when the amniotic fluid was hyperosmolar, the rate at 30 minutes was markedly lower than those of isosmotic or hyposmotic amniotic fluid. At 90 minutes, the rate of $Li^+$ disappearance in hyperosmolar fluid reached a similar level to the rate in isosmolar fluid. 5. The intraamniotic injection of 400 mOsm/L saline solution decreased the disappearance rate of $Li^+$ from expired fetuses, while the injection of mannitol into the maternal vein induced no significant change. From these results it is concluded that: 1) a significant amount of $Li^+$ may leave the amniotic fluid via filtration through the membranes surrounding the amniotic fluid, 2) during hyperosmolar challenge to amniotic fluid, osmotic bulk flow might counteract the filterable loss, and 3) $Li^+$ disappearance might continue even after the volume and osmolarity of the amniotic fluid have recovered to control values.

A proposal of the Optimal Angle of Standing Assistant Chair for the Elderly by Comparing of Pressure Distribution on Hip

Sung-Ho Chang(장성호),Ji-Hoon Baek(백지훈),Jung-Eon Lee(이중언),Nematov Mirazamjon(Nematov Mirazamjon),Seok-Wan-Kang(강석완),Wang-Bum Lee(이왕범) 한국산업경영시스템학회 2018 한국산업경영시스템학회지 Vol.41 No.3

One of the most performed action in daily life is standing up from sitting position. As the population of the world is aging at the high rates, people may face problems with reduced muscle strength as well as psychological changes. This can lead elderly people having difficulties with standing up from chair. Now, with the aging trend worldwide, products are being developed that can support the lives of the elderly. This study examines the distribution of hip pressure in relation to the seating positions of the standing assistance seats under development to prevent standing up accidents in older adults. The currently developing standing assistant chair designed to tilt to a maximum angle of 25 degrees. At over 25°, design considers that older people are at risk of thrown back out of that force and that the forces exerted on their arms and legs can be a significant burden to older people. By considering danger of higher than 25° for older people which is experimented in the basis of static capturing approach in previous papers, it is experimented people with age group of 20~60 on 0° to 25° tilting angle on the basis of dynamic capturing method in order to pick convenient angle of inclination. Moreover, tried to find the optimum angle by comparing the hip pressure distribution when seated at the edge of the seat and at the center of the seat with the pressure distribution sensor.

또래학습을 통한 또래교사와 또래학습자의 인지구조 변화 -초등 도형영역에 대하여-

김미정 ( Mi Jung Kim ),이광호 ( Kwang Ho Lee ),이미진 ( Mi Jin Lee ),성창근 ( Chang Geun Sung ) 한국수학교육학회 2013 初等 數學敎育 Vol.16 No.2

본 연구는 또래교수 활동을 통하여 변화된 도형의 개념 및 성질, 도형간의 관계에서 인지구조를 관찰하고 어떻게 정교화 해 가는지에 대해 또래교사와 또래학습자의 인지 구조의 차이를 알아보았다. 연구 문제를 해결하기 위해 보은의 S초등학교 5학년 학생 6명을 대상으로 또래교수와 학습자 3팀을 선정하고 도형영역에 대한 사전·사후검사를 실시하고 자료를 분석하였으며 심층면담을 실시하여 인지구조를 분석하였다. 또래교사와 또래학습자 모두 도형영역에서 인지구조가 변화되었으며 특히 또래교사의 인지구조의 변화가 더욱 뚜렷이 나타났다. 따라서 또래교수활동은 체계적인 계획하에 일관성 있는 교수활동 뿐만이 아니라 학습활동에 더욱더 많은 교사의 지속적인 노력과 지원이 필요하다. The purpose of the study is finding the effective teaching and learning methods on the concepts of figures through exploring the change of students` cognitive structures before and after the peer teaching activities. The difference of the peer teacher`s and student`s cognitive structures was investigated for the activities. Three teams, six students of 5th grade, were selected from the S elementary school in Boyeon. To figure out the students` cognitive structures, pre and post in-depth interviews were conducted and analyzed. Both peer teachers` and learners` cognitive structures were changed. Peer teachers` cognitive structures were changed more positively than peer learners. A consistent systematic planation and continuous teacher support and effort are needed for the activities.

Optimal parameter derivation for Muskingum method in consideration of lateral inflow and travel time

Kim, Sang Ho,Kim, Ji-sung,Lee, Chang Hee 한국수자원학회 2017 한국수자원학회논문집 Vol.50 No.12

하도홍수추적 방법에서 많이 사용되고 있는 Muskingum 방법의 가장 중요한 매개변수는 저류상수와 가중인자이다. Muskingum 방법은 상류 유입지점에서 하류 유출지점까지 측방유입량이 고려되지 않지만, 실제 유역에는 강우로 인하여 측방유입유량이 발생한다. 이로 인해 상하류 실측 자료를 이용하여 저류상수 및 가중인자를 산정하는 것이 매우 어려운 상황이다. 이에 본 연구는 HEC-RAS 1차원 부정류 해석모형을 이용한 수리학 적 홍수추적을 통해 측방유입유량이 제외된 상태에서의 하도에서 전파되는 유량을 산정하였고, 이를 이용하여 저류상수 및 가중인자를 산정하는 방법을 제시하였다. 이와 함께 저류상수가 유하시간과 관계있음을 감안하여 국내 하천기본계획 수립 시 사용되는 유하시간 경험 공식들을 저류상수로 적용한 결과를 비교 분석하였다. 마지막으로 유량이 고려된 유하시간 산정식을 개발하고, 유입량의 변화에 맞춰 유하시간을 업데이트하여 모의를 수행하는 방법을 제시하였다. 유량을 고려한 유하시간을 저류상수로 적용한 경우, 유량의 상승 및 하강 과정, 첨두 유량, 그리고 첨두 시간에 대해서 잘 모의하는 것으로 분석되었다. The most important parameters of the Muskingum method, widely used in hydrologic river routing, are the storage coefficient and the weighting factor. The Muskingum method does not consider the lateral inflow from the upstream to the downstream, but the lateral inflow actually occurs due to the rainfall on the watershed. As a result, it is very difficult to estimate the storage coefficient and the weighting factor by using the actual data of upstream and downstream. In this study, the flow without the lateral inflow was calculated from the river flow through the hydraulic flood routing by using the HEC-RAS one-dimensional unsteady flow model, and the method of the storage coefficient and the weighting factor calculation is presented. Considering that the storage coefficient relates to the travel time, the empirical travel time formulas used in the establishment of the domestic river basin plan were applied as the storage coefficient, and the simulation results were compared and analyzed. Finally, we have developed a formula for calculating the travel time considering the flow rate, and proposed a method to perform flood routing by updating the travel time according to the inflow change. The rise and fall process of the flow rate, the peak flow rate, and the peak time are well simulated when the travel time in consideration of the flow rate is applied as the storage coefficient.

Influence of Growth Temperature on the Characteristics of Single-Junction p—i—n InGaP Solar Cells

Jung, Sang Hyun,Kim, Youngjo,Kim, Chang Zoo,Jun, Dong-Hwan,Kim, Kangho,Shin, Hyun-Beom,Choi, JeHyuk,Park, Won-Kyu,Lee, Jaejin,Kang, Ho Kwan American Scientific Publishers 2017 Journal of nanoscience and nanotechnology Vol.17 No.4

<P>Single-junction p-i-n InGaP solar cells are grown at various temperatures from 620 to 700 degrees C by low pressure metalorganic chemical vapor deposition on GaAs (001) substrates. The short circuit current density of the p-i-n InGaP solar cells increases by up to 38.8% when the growth temperature is reduced from 700 to 620 degrees C, while the open circuit voltage and fill factor show relatively small changes. The external quantum efficiency, especially, in the wavelength regime below 500 nm, is improved for the p-i-n InGaP solar cells grown at lower temperatures. The improvement might be attributed to the reduced absorption loss of the photons in the n-InGaP emitter region. The highest conversion efficiency of 11.01% is attributed from the p-i-n InGaP solar cell grown at 640 degrees C. Electron mobility and concentration of undoped InGaP layers are investigated as a function of the growth temperature and correlated with the p-i-n InGaP solar cell performance.</P>

자동차 칵핏 모듈용 플라스틱 소재의 열화 동특성 평가

우창수(Chang Su Woo),박현성(Hyun Sung Park),조진호(Jin Ho Jo),김지훈(Ji Hoon Kim),최주호(Ju Ho Choi),김영국(Yeoung Kuk Kim) 대한기계학회 2012 大韓機械學會論文集A Vol.36 No.12

플라스틱 소재는 온도, 습도 및 자외선 등 다양한 환경의 영향으로 인해 기계적 물성변화가 심하기 때문에 체결부의 견고함이 느슨해지고 형태의 변형에 의해 부품간의 마찰 등을 유발하여 잡음이 발생하게 된다. 따라서, 본 논문에서는 자동차 칵핏 모듈에 사용되는 다양한 플라스틱 소재에 대해 온도변화에 따른 동 특성시험을 통해 유리전이온도, 저장탄성계수, 손실계수 등을 측정하여 상온 및 열화조건에 따른 물성변화를 파악하였다. 시험결과, 온도가 높을수록 저장탄성계수는 감소하고 손실계수는 증가하는 경향을 나타내었다. Engineering plastics are used in instrument panels, interior trim, and other vehicle applications, and the thermomechanical behaviors of plastic materials are strongly influenced by many environmental factors such as temperature, sunlight, and rain. As the material properties change, the mechanical parts create unexpected noise. In this study, the dynamic mechanical property changes of plastics used in automobiles are measured to investigate the temperature effects. Viscoelastic properties such as the glass transition temperature and storage modulus and loss factor under temperature and frequency sweeps were measured. The data were compared with the original ones before aging to analyze the behavior changes. It was found that as the temperature increased, the storage modulus decreased and the loss factor increased slightly.