Kwak, Ji Hyun;Hwang, Seung-Ryul;Lee, Yeon-Hee;Kim, Jae-Young;Song, Ki Bong;Kim, Kyun;Kang, Jae Eun;Lee, Sang Jae;Jeon, Junho;Lee, Jin Hwan
Korean Journal of Environmental Agriculture
/
v.34
no.2
/
pp.134-138
/
2015
BACKGROUND: In recent years, several researchers have focused on odour control methods to remove the harmful chemicals from chemical accidents and incidents. The present work deals with the system development of the hazardous. METHODS AND RESULTS: For on-site removal of hazardous gaseous materials from chemical accidents, mobile vortex wet scrubber was designed with water vortex process to absorb the gas into the water. The efficiency of the mobile vortex wet scrubber was evaluated using water spray and 25% ammonia solution. The inlet air velocity (gas flow rate) was according to the damper angle installed within the hood and with increase of gas flow rate, consequently the absorption efficiency was markedly decreased. In particular, when 25% ammonia solution was exposed to the hood inlet for 30 min, the water pH within the scrubber was changed from 7 to 12. Interestingly, although the removal efficiency of ammonia gas exhibited approximately 80% for 5 min, its efficiency in 10 min showed the greatest decrease with 18%. Therefore, our results suggest that the ammonia gas may be absorbed with the driving force of scrubbing water in water vortex process of this scrubber. CONCLUSION: When chemical accidents are occurred, the designed compact scrubber may be utilized as effective tool regarding removal of ammonia gas and other volatile organic compounds in the scene of an accident.
Park, Hye-Suk;Kim, Ye-Seul;Kim, Sang-Tae;Park, Ok-Seob;Jeon, Chang-Woo;Kim, Hee-Joung
Progress in Medical Physics
/
v.22
no.4
/
pp.163-171
/
2011
The purpose of this study was to investigate the effect of various technical parameters for the dose optimization in pediatric chest radiological examinations by evaluating effective dose and effective detective quantum efficiency (eDQE) including the scatter radiation from the object, the blur caused by the focal spot, geometric magnification and detector characteristics. For the tube voltages ranging from 40 to 90 kVp in 10 kVp increments at the FDD of 100, 110, 120, 150, 180 cm, the eDQE was evaluated at the same effective dose. The results showed that the eDQE was largest at 60 kVp when compares the eDQE at different tube voltage. Especially, the eDQE was considerably higher without the use of an anti-scatter grid on equivalent effective dose. This indicates that the reducing the scatter radiation did not compensate for the loss of absorbed effective photons in the grid. When the grid is not used the eDQE increased with increasing FDD because of the greater effective modulation transfer function (eMTF). However, most of major hospitals in Korea employed a short FDD of 100 cm with an anti-scatter grid for the chest radiological examination of a 15 month old infant. As a result, the entrance surface air kerma (ESAK) values for the hospitals of this survey exceeded the Korean DRL (diagnostic reference level) of $100{\mu}Gy$. Therefore, appropriate technical parameters should be established to perform pediatric chest examinations on children of different ages. The results of this study may serve as a baseline to establish detailed reference level of pediatric dose for different ages.
In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.
Lee, Kee-Joon;Nah, Hyun-Duck;Tjoa, Stephen T. J.;Park, Young-Chel;Baik, Hyoung-Seon;Yun, Tae-Min;Song, Jin-Wook
The korean journal of orthodontics
/
v.36
no.4
/
pp.284-294
/
2006
Objective: Activating mutations in the fibroblast growth factor receptor-2 (FGFR2) have been shown to cause syndromic craniosynostosis such as Apert and Crouzon syndromes. The purpose of this pilot study was to investigate the resultant phenotypes induced by the two distinctive bone-targeted gene constructs of FGFR2, Pro253Arg and Cys278Phe, corresponding to human Apert and Crouzon syndromes respectively. Methods: Wild type and a transgenic mouse model with normal FGFR2 were used as controls to examine the validity of the microinjection. Micro-CT and morphometric analysis on the skull revealed the following results. Results: Both Apert and Crouzon mutants of FGFR2 induced fusion of calvarial sutures and anteroposteriorly constricted facial dimension, with anterior crossbite present only in Apert mice. Apert mice differed from Crouzon mice and transgenic mice with normal FGFR2 in the anterior cranial base flexure and calvarial flexure angle which implies a possible difference in the pathogenesis of the two mutations. In contrast, the transgenic mice with normal FGFR2 displayed normal craniofacial phenotype. Conclusion: Apert and Crouzon mutations appear to lead to genotype-specific phenotypes, possibly causing the distinctive sites and sequence of synostosis in the calvaria and cranial base. The exact function of the altered FGFR2 at each suture needs further investigation.
Various pretreatment methods were evaluated to prevent tissue softening of heated onion. Changes in onion tissue firmness during heating were explained by 3-mechanism model consisting of texture hardening at low temperature ($60-80^{\circ}C$) and substrate softening at high temperature. Preheating of onion in a $Ca^{2+}$-containing solution significantly improved its texture after high-temperature heating. The improvement of firmness by preheating at low temperature was related to the formation of strong cross-linking between carboxyl groups and $Ca^{2+}$ by the action of pectin methylesterase in onion. The highest firmness was obtained by pre-heating at $70^{\circ}C$ for 120 min in 0.5% calcium solution. This result was supported by chemical analysis showing that the amount of bound calcium was the highest at $70^{\circ}C$. Further investigation should be carried out to establish the optimal conditions to prevent the softening of various vegetables.
The purpose of this study was to obtain basic data for using Aronia as a functional food material. The composition of anthocyanin was characterized and quantitated by LC-MS/MS, HPLC, and UV-VIS spectrophotometer techniques, respectively. The anthocyanin content was analyzed by temperature, time, pH, and the addition of citric acid. The UV-VIS spectrophotometer used for analysis of anthocyanin is less accurate than the LC-MS/MS method used in recent years. In the past, cyanidin-3-Glucoside was reported to be a major anthocyanin that contains Aronia. However, LC-MS/MS analysis in this study confirmed cyanidin-3-galactoside to be the major compound. The anthocyanin content of the Aronia powder began to decrease sharply at a temperature of $65^{\circ}C$ or higher when heated for 24 hours. In an aqueous solution of Aronia, the anthocyanin content was reduced by 50% at $65^{\circ}C$ for 10 hours and decreased by 85% at $85^{\circ}C$ within 10 hours. Above pH 8, the anthocyanin content was reduced by more than 50%. The results of this study will provide useful information to maintain anthocyanin content in the manufacturing process of Aronia. It could also be used to ensure the stability of anthocyanins in similar species of berries.
Objectives: Shift work is a stressful situation. It is important to know the factors associated with the ability to adapt to a shift work schedule. The aim of the present study was to investigate the association between sleep, as well as personality variables, and the resilience of shift work nurses. Method: Self-report questionnaires were administered to 95 nurses who worked in one national university hospital. Connor-Davidson resilience scale, hospital anxiety and depression scale, morningness-eveningness scale, Pittsburgh sleep quality index, other sleep-related questionnaires, and Korean defense style questionnaires were used. Results: Age, shift work duration, off-day oversleep, depression, anxiety, adaptive defense style, and self-suppressive defense style were significantly associated with resilience (p < 0.05). Multiple regression analysis showed that age (${\beta}=0.34$, p < 0.05), depression (${\beta}=-0.25$, p < 0.05), adaptive defense style (${\beta}=0.45$, p < 0.001), and self-suppressive defense style (${\beta}=-0.19$, p < 0.05) significantly predicted the resilience of shift work nurses. Concerning individual defense mechanisms, resignation (${\beta}=-0.20$, p < 0.05), sublimation (${\beta}=0.19$, p < 0.05), omnipotence (${\beta}=0.19$, p < 0.05), and humor (${\beta}=0.20$, p < 0.05) significantly predicted the resiliency. Conclusion: The findings indicate that a specific defense style and other mechanisms were associated with the resilience of shift work nurses. A future prospective study with more participants could further clarify the relationship between sleep-related variables, as well as personality factors, and resilience of shift work nurses.
Cho Sung-Il;Kim Chun-Soo;Bae Dae-Seok;Kim Kyung-Su;Song Moo-Young
The Journal of Engineering Geology
/
v.16
no.1
s.47
/
pp.69-83
/
2006
This study aims to evaluate a complex groundwater flow system around the underground oil storage caverns using the concept of hydraulic compartment. For the hydrogeological analysis, the hydraulic testing data, the evolution of groundwater levels in 28 surface monitoring boreholes and pressure variation of 95 horizontal and 63 vertical water curtain holes in the caverns were utilized. At the cavern level, the Hydraulic Conductor Domains(fracture zones) are characterized one local major fracture zone(NE-1)and two local fracture zones between the FZ-1 and FZ-2 fracture zones. The Hydraulic Rock Domain(rock mass) is divided into four compartments by the above local fracture zones. Two Hydraulic Rock Domains(A, B) around the FZ-2 zone have a relatively high initial groundwater pressures up to $15kg/cm^2$ and the differences between the upper and lower groundwater levels, measured from the monitoring holes equipped with double completion, are in the range of 10 and 40 m throughout the construction stage, indicating relatively good hydraulic connection between the near surface and bedrock groundwater systems. On the other hand, two Hydraulic Rock Domains(C, D) adjacent to the FZ-1, the groundwater levels in the upper and lower zones are shown a great difference in the maximum of 120 m and the high water levels in the upper groundwater system were not varied during the construction stage. This might be resulted from the very low hydraulic conductivity$(7.2X10^{-10}m/sec)$ in the zone, six times lower than that of Domain C, D. Groundwater recharge rates obtained from the numerical modeling are 2% of the annual mean precipitation(1,356mm/year) for 20 years.
The soil samples were collected from the paddy field near the mine tailing dumps in the abandoned Duckum mine in Korea. In the laboratory, the soil solution was extracted from the soil using centrifuge, and analysed for the chemical composition. Physical and chemical soil properties were also analysed. Kaolinite is the main clay minerals in the paddy soil and the CEC value is therefore relatively low. Nearly all soil samples show enrichment in their trace elemental concentrations(Cd, Cu, Pb and Zn) compared with natural background level. Some soil samples exceed the soil remediation intervention values for Cd, Pb and Zn and target value for Cu, when compared with Dutch standard, whereas As, Ni and Cr are in normal range. Lead concentrations in some samples near the mine tailing dumps also exceed the standard for remediation act for agricultural area set by Korean soil conservation law. The trace elemental concentrations are higher in the paddy soil nearer the mine tailing dumps and lower for the samples from distance. Similar trend with distance is found for the soil solution chemistry but the decrease with distance from the mine tailing dumps are sharper than the changes in soil chemistry. Cadmium, Cu and Pb concentrations in the soil solution are very low, ranging from a tenth and hundredths to a maximum of several mg/l, whereas their concentrations in soils are highly enriched for natural background. Most of the trace elements are thought to be either removed by reduced iron sulphides or iron oxides, depending on the redox changes. Geochemical equilibrium modelling indicate the presence of solubility controlling solid phases for Cd and Pb, whereas Zn and Cu might have been controlled by adsorption/desorption processes. Although pollutants migration through solution phase are thought to be limited by adsorption onto various Fe, Mn solid phases, the pollutants exist as easily releasable fractions such as exchangeable site. In this case, the paddy soil would act as pollutant pool, which will supply to plants in situ. whenever the geochemical conditions favour.
Journal of the Korean Association of Geographic Information Studies
/
v.12
no.1
/
pp.64-72
/
2009
The method to generate a digital elevation model(DEM) from contour lines causes a problem in which the low relief landform cannot be clearly presented due to the fact that it is significantly influenced by the expression of micro landform elements according to the interval of contours. Thus, this study attempts to develop a landcover burning method that recovers the micro relief landform of the DEM, which applies buffering and map algebra methods by inputting the elevation information to the landcover. In the recovering process of the micro landform, the DEM was recovered using the buffering method and elevation information through the map algebra for the landcover element for the micro landform among the primary DEM generation, making landcover map, and landcover elements. The recovering of the micro landform was applied based on stream landforms. The recovering of landforms using the buffering method was performed for the bar, which is a polygonal element, and wetland according to the properties of concave/convex through generating contours with a uniform interval in which the elevation information applied to the recovered landform. In the case of the linear elements, such as bank, road, waterway, and tributary, the landform can be recovered by using the elevation information through applying a map algebra function. Because the polygonal elements, such as stream channel, river terrace, and artificial objects (farmlands) are determined as a flat property, these are recovered by inputting constant elevation values. The results of this study were compared and analyzed for the degree of landform expression between the original DEM and the recovered DEM. In the results of the analysis, the DEM produced by using the conventional method showed few expressions in micro landform elements. The method developed in this study well described wetland, bar, landform around rivers, farmland, bank, river terrace, and artificial objects. It can be expected that the results of this study contribute to the classification and analysis of micro landforms, plain and the ecology and environment study that requires the recovering of micro landforms around streams and rivers.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.