• Title/Summary/Keyword: Spot measurement

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Overview of new developments in satellite geophysics in 'Earth system' research

  • Moon Wooil M.
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.06a
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    • pp.3-17
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    • 2004
  • Space-borne Earth observation technique is one of the most cost effective and rapidly advancing Earth science research tools today and the potential field and micro-wave radar applications have been leading the discipline. The traditional optical imaging systems including the well known Landsat, NOAA - AVHRR, SPOT, and IKONOS have steadily improved spatial imaging resolution but increasing cloud covers have the major deterrent. The new Earth observation satellites ENVISAT (launched on March 1 2002, specifically for Earth environment observation), ALOS (planned for launching in 2004 - 2005 period and ALOS stands for Advanced Land Observation Satellite), and RADARSAT-II (planned for launching in 2005) all have synthetic aperture radar (SAR) onboard, which all have partial or fully polarimetric imaging capabilities. These new types of polarimetric imaging radars with repeat orbit interferometric capabilities are opening up completely new possibilities in Earth system science research, in addition to the radar altimeter and scatterometer. The main advantage of a SAR system is the all weather imaging capability without Sun light and the newly developed interferometric capabilities, utilizing the phase information in SAR data further extends the observation capabilities of directional surface covers and neotectonic surface displacements. In addition, if one can utilize the newly available multiple frequency polarimetric information, the new generation of space-borne SAR systems is the future research tool for Earth observation and global environmental change monitoring. The potential field strength decreases as a function of the inverse square of the distance between the source and the observation point and geophysicists have traditionally been reluctant to make the potential field observation from any space-borne platforms. However, there have recently been a number of potential field missions such as ASTRID-2, Orsted, CHAMP, GRACE, GOCE. Of course these satellite sensors are most effective for low spatial resolution applications. For similar objects, AMPERE and NPOESS are being planned by the United States and France. The Earth science disciplines which utilize space-borne platforms most are the astronomy and atmospheric science. However in this talk we will focus our discussion on the solid Earth and physical oceanographic applications. The geodynamic applications actively being investigated from various space-borne platforms geological mapping, earthquake and volcano .elated tectonic deformation, generation of p.ecise digital elevation model (DEM), development of multi-temporal differential cross-track SAR interferometry, sea surface wind measurement, tidal flat geomorphology, sea surface wave dynamics, internal waves and high latitude cryogenics including sea ice problems.

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A Numerical Study on the Effects of Buildings and Topography on the Spatial Distributions of Air Pollutants in a Building-Congested District (건물 밀집 지역에서 대기오염물질 분포에 미치는 건물과 지형의 영향에 관한 수치 연구)

  • Kang, Geon;Kim, Jae-Jin;Lee, Jae-Bum
    • Korean Journal of Remote Sensing
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    • v.36 no.2_1
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    • pp.139-153
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    • 2020
  • Using a computationalfluid dynamics(CFD) model, thisstudy evaluated the representativeness of an air quality monitoring system (AQMS) in an urban area and presented a methodology to determine the suitable AQMS locations for specific purposes. For this, we selected a 1.6 km × 1.6 km area around the Eunpyeong-gu AQMS (AQMS 111181) as a target area. We conducted simulationsfor two emission scenarios (scenario one: air pollutants transported from inflow boundaries, scenario two: air pollutants emitted from roads). Urban airflows were markedly influenced by mountainous terrain located in the northeast and southeast of the target area, and complicated airflow patterns occurred around the buildings. The distributions of air pollutants were dependent on the terrain (mountain) in scenario one, but the road location and building height in scenario 2. We evaluated whether the AQMS could represent the air quality in the target area based on the simulations for two scenarios. The concentrations simulated at the AQMS were similar in magnitude to the layer mean concentrations, which indicated good representativeness for the air quality in the target area. We also suggested which locations were suitable for different measurement purposes (hot spots, clean zones, average zones, shelter zones, equi-background zones).

A study on practice of obesity control by school nurses (보건교사의 비만관리실태 조사연구)

  • Ju, Hyun-Ok;Song, Mi-Gyoung
    • Journal of the Korean Society of School Health
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    • v.15 no.2
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    • pp.249-261
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    • 2002
  • This study was a research study to find out the real picture and practice of student obesity control by primary, middle and high school school nurses. The study sampled 196 school nurses working in the Busan City and Northern Gyungsang Province, who agreed on the purpose of the study. When it comes to the study process, at the meeting of the whole school nurses, the researcher explained the purpose of the study and asked them to complete questionnaires and return on the spot. The study is designed to provide basic data for school nurses in field to systematically and efficiently control student obesity by examining perception of school obesity control and the real picture or practice of obesity control as well as its problems. The study used SPSS 10.0 to analyze data. The results are as follows: Annual plans about obesity control appeared significant at the primary school, 89.3%, higher than 77.3% of the middle and high school(p<0.05). Annual project evaluation showed a significant difference by regions, 56.0% of metro cities vs. small cities(p<0.01). The number of measuring weight of obese students was higher at the primary school than at the middle and high school(p<0.05). Also small cities conducted the weight measurement more often than metro cities(p<0.001). Among the health education methods for obesity, counseling appeared statistically significant(p<.01). The health education showed a significant difference in more experienced school nurses. Among the educational media, environment postings were used at the primary school, 24.0%, higher than 5.3% of the middle and high school. It showed a significant difference(p<.001). OHP or epidiascopes were used at the primary school, 36.4%, significantly higher than the middle and high school(p<.001). In addition, computer was used at the primary school, 21.5%, higher than the middle and high school(p<.05). Problems of obesity education data included a lack of textbooks and programs and a short of educational media. However it didnt show a significant difference in schools or in regions. Counseling activities for obesity showed a significant difference in schools(p<.01) and in regions(p<.001). When parents with obese students were in counseling, those in their 20s used home correspondence and those in their 30s and 40s used phone call(p<.01). The rate of equipment to measure obesity was higher at the middle and high school than the primary school, showing a significant difference(p<.001). Therefore, regular health education curriculums for school nurses should be systematically created to promote student health. Furthermore, it needs to make standard textbooks for health education by grades as well as by levels and to develop various educational programs and educational media.

A Study on Application of GPS for Deflection Management of Curved PCT Girder Bridge under Construction (시공 중 곡선형 PCT 거더교의 처짐 관리를 위한 GPS 적용 연구)

  • Kyu Dal, Lee;Jin Duk, Lee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.5
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    • pp.453-461
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    • 2015
  • In order to manage the deflection of a curved PCT girder bridge during construction, a GPS receiver was installed at the spot predicted to be the weak point during the incremental launching so as to measure the deflection at each construction stage. The deflections obtained in the experiment were compared with those derived from the monitoring of stress, temperature and inclination. The comparative analysis of the GPS measurement and analytical values obtained from finite element modeling with respect to the launching distance showed that the measured values differ by 0.6 to 1.6 times to the analytical results. This difference could be significantly reduced by thermal calibration. From the analysis of the behavioral pattern of the bridge, deflection occurred during construction in the concrete tip due to the deflection at the head of the nose at the 95m and 75m-spots, and compression and tension developed respectively at the compression weak zone and tension weak zone. The application of GPS appeared to enable more efficient management of the deflection during the erection of the curved PCT girder bridge and is expected to be helpful for the prediction and management of the behavior in future ILM construction sites.

A Study on Travelling Characteristics and Choice of Proper Location of Dam Discharge Alarm Broadcasting (댐 방류 경보방송의 전달 특성 및 적정 위치 선정에 관한 연구)

  • Kim, Dae-Goon;Kim, Jae-Soo
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.8
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    • pp.635-640
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    • 2009
  • After 1960s, in accordance with getting bigger in changing range of annual rain precipitation, those dams were built in order to prevent any drought and flood through the regulation of flux. In case of such dam, when it reaches to some definite pondage, for its regulation of water volume, numerous volume of water in the reservoir should be discharged by opening the floodgate, at this time a severe damage can be occurred to those lives and properties of the residents and tourists at the river or riverside. Accordingly, despite the sounding alarm broadcasting for prevention and notice such damage could be clearly travelled to those people without influence by the discharging noise or other neighboring environmental factor, since it was only empirically installed without any peculiar research until now, the alarm broadcasting could not effectively travel, and the travelling distance also could not known correctly. On such point of view, this Study has ever grasped the characteristics by frequencies and its sound pressure level about the discharge noise and the alarm broadcasting of Daechung Dam, one of multipurpose dams through the measurement and analysis by distances, and based on this, also has ever presupposed the proper location of additional alarm broadcasting spot using a simulation program named Cadna-A.

A Vibration Evaluation and Improvement Scheme for Open Test Blasting (노천시험발파의 진동평가와 개선방안)

  • Kim, Eung-Rok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.310-315
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    • 2017
  • Although studies evaluating the effects of the blasting vibration on the adjacent structures from various angles have continued, cases of securing the safety of the adjacent buildings and researching the proper blasting method for the field condition by analyzing the vibration waveform of the measuring field while performing the open pit blasting are poor. Therefore, it is necessary to present a remedy for blasting pattern selection through test blasting that is appropriate for field conditions, and is economical and efficient. In this study, open pit blasting work was conducted based on the separation distance applied according to the standard blasting method by test blasting and the vibration regulation standard in the road expansion construction site to measure the blasting vibration value, and the vibration prediction equation by blasting methods was examined using a regression analysis computer program to calculate K, N, and R of the confidence level 95%. By setting the blasting allowed vibration standard of the test blasting target area to 0.3cm/sec, and the charring weight and blasting method by the separation distances according to the blasting vibration estimation equation of the open pit blasting guideline and the blasting vibration estimation equation of the test blasting were compared/analyzed, it was possible to identify the factors that increased the working expenses. In addition, the measurement and analysis of the adjacent structures during open pit blasting and the blasting vibration were performed after selecting the most adjacent structure to the open pit blasting spot to analyze the problems on the test blasting procedure and analysis method in the open pit blasting design/construction guidelines, which appeared in the process of completing open pit blasting construction, and a remedy is presented.

Quasi-monochromatic Parallel Radiography Achieved with a Polycapillary Plate

  • Sato, Eiichi;Komatsu, Makoto;Hayasi, Yasuomi;Tanaka, Etsuro;Mori, Hidezo;Kawai, Toshiaki;Ichimaru, Toshio;Takayama, Kazuyoshi;Ido, Hideaki
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.418-421
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    • 2002
  • Fundamental study on quasi-monochromatic parallel radiography using a polycapillary plate and a plane-focus x-ray tube is described. The x-ray generator consists of a negative high-voltage power supply, a filament (hot cathode) power supply, and an x-ray tube. The negative high-voltage is applied to the cathode electrode, and the transmission type target (anode) is connected to the ground potential. The maximum voltage and current of the power supply were -100 kV (peak value) and 3.0 mA, respectively. In this experiment, the tube voltage was regulated from 20 to 25 kV, and the tube current was regulated by the filament temperature and ranged from 1.0 to 3.0 mA. The exposure time is controlled in order to obtain optimum film density, and the focal spot diameter was about 10 mm. The polycapillary plate is J5022-21 made by Hamamatsu Photonics Inc., and the outside and effective diameters are 87 and 77 mm, respectively. The thickness and the hole diameter of the polycapillary are 1.0 mm and 25 ${\mu}$m, respectively. The x-rays from the tube are formed into parallel beam by the polycapillary, and the radiogram is taken using an industrial x-ray film of Fuji IX 100 without using a screen. In the measurement of image resolution, we employed three brass spacers of 2, 30, and 60 mm in height. By the test chart, the resolution fell according to increases in the spacer height without using a polycapillary. In contrast, the resolution slightly fell with corresponding increases in the height by the polycapillary. In angiography, fine blood vessels of about 100 ${\mu}$m are clearly visible.

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A Study on Adequacy of Pipe Deterioration Evaluation Methods using the Endoscope of Water Distribution Pipe (배수관 내시경 조사를 통한 간접적인 관 노후도 평가방법의 적정성 연구)

  • Choi, Tae Ho;Kang, Sin Jae;Choi, Jae Ho;Koo, Ja Yong
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.5
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    • pp.669-683
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    • 2012
  • The water supply pipes are buried across wide range of areas, so it is hard to spot them using excavation and takes a large amount of expense. Thus, there is a high risk for direct research and application, accompanying many difficulties in implementation of them. Therefore, it is more economical and convenient to use indirect evaluation variables than direct evaluation of the buried pipes in assessing the degree of pipe deterioration. To assess the degree of pipe deterioration using the indirect evaluation variables, it should be done first to identify how and to what extent they affect the degree of deterioration. This study measured the evaluation variables for pipe deterioration using the pipe endoscope and analyzed the measurement results and the degree of impact on the pipes. In addition, this study attempted to evaluate the adequateness of the pipe deterioration evaluation using the indirect variables based on the analysis results. The evaluation variables measured through the pipe endoscope were the thickness of sediments, size of scale, degree of desquamation and condition of connections. For the indirect evaluation variables, the data such as the property data from GIS pipe network map as well as the material, diameter, age and pipe lining material of the pipe, road type, leakage frequency, average water velocity and water pressure using the leakage repair records was collected. Using the collected data, this study comparatively analyzed the indirect evaluation variables for the degree of pipe deterioration and the results from the pipe endoscope to choose appropriate variables for pipe deterioration evaluation and calculated the weights of the indirect variables on the degree of deterioration. The results showed that the order of the impact of indirect variables on deterioration was pipe age > pipe lining material > road type > leakage frequency > average water velocity with their weights of 0.45, 0.20, 0.15, 0.10, and 0.10, respectively. Conclusively, the results suggest that the measures of sediment thickness, scale size, degree of desquamation and condition of connections are appropriate for the evaluation of pipe deterioration and sufficient for the analysis of the impact of the indirect variables on deterioration.

Characterization of Porcine Tissue Perforation Using High-Power Near-Infrared Laser at 808-nm Wavelength (808 nm 파장의 고출력 근적외선 레이저 조사 시 돼지 조직의 천공 특성 연구)

  • Kim, Seongjun;Cho, Jiyong;Choi, Jaesoon;Lee, Don Haeng;Kim, Jung Kyung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.9
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    • pp.807-814
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    • 2013
  • A fundamental study on laser-tissue interaction was conducted with the aim of developing a therapeutic medical device that can remove lesions on the intestinal wall by irradiating a high-power 808-nm infrared laser light incorporated in an endoscopic system. The perforation depth was linearly increased in the range of 1~4 mm in proportional to laser output (3~12 W) and irradiation time (5~20 s). We demonstrated that the perforation depth during laser irradiation was varied according to the tissue property of each extracted porcine organ. The measurement of the temperature distribution suggests that the energy is localized in the irradiation spot and transferred to deep tissue, which protects the surrounding tissue from thermal injury. These results can be used to set the driving parameters for a laser incision technique as an alternative to conventional surgical interventions.

Measurement of Microbial Protein Supply in Murrah Buffaloes (Bubalus bubalis) Using Urinary Purine Derivatives Excretion and PDC Index

  • Dipu, M.T.;George, S.K.;Singh, P.;Verma, A.K.;Mehra, U.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.3
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    • pp.347-355
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    • 2006
  • A study was conducted to predict the rumen microbial protein production based on urinary excretion of purine derivatives in buffaloes fed a diet of wheat straw and concentrate (40:60) at four fixed levels of feed intake. (95, 80, 60 and 40% of preliminary voluntary feed intake) following experimental protocol of IAEA (Phase I). The buffaloes were allocated according to a $4{\times}4$ latin square design. The urinary allantoin, uric acid, total PD excretion (mmol/d) in treatments L-95, L-80, L-60 and L-40 was 20.13, 16.00, 12.96 and 9.17; 1.88, 2.12, 2.11 and 2.15; 22.01, 18.12, 15.07 and 11.32, respectively and were significantly (p<0.05) different among treatments except for uric acid. The rate of PD excretion (mmol/d) was positively correlated with the digestible organic matter intake. Variations were observed in PD and creatinine concentration in spot samples collected at 6-hour interval. However, daily PD:Creatinine ratio (PDC index) appears to be a reasonably good predictor of microbial-N supply. The contribution of basal purine excretion to total excretion of purine derivatives (PD) was determined in pre-fasting period followed by a fasting period of 6 d (Phase II). Daily PD and creatinine excretion (mmol/kg $W^{0.75}$) during fasting averaged 0.117 and 0.456 respectively for buffaloes. The excretion rates of PD decreased significantly (p<0.01) during fasting compare to pre-fasting period, the urinary creatinine excretion remained almost similar. Except for creatinine, plasma concentration of target parameters significantly (p<0.01) declined during fasting. Likewise, glomerular filtration rate (GFR) and renal clearance of allantoin and uric acid also decreased. Based on the PD excretion rates during fasting and at different levels of feed intake obtained in this study, a relationship between daily urinary PD excretion (Y-mmol) and microbial purine absorption (X-mmol) was developed for buffaloes as Y = 0.74X+0.117 kg $W^{0.75}$. The microbial N supply (g/kg DOMI) remained statistically similar irrespective of dietary treatment. The results showed that excretion of urinary purine derivatives is positively correlated with the levels of feed intake in Murrah buffaloes and thus, estimation of urinary purine derivatives and PDC index could be used to determine microbial nitrogen supply when there is large variation in level of feed intake.