• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.137-145
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• 2008

In this study, to reduce the flood damage caused by flood discharge exceeding project flood, the primary technology was applied to determining the optimal location and size for underground sluiceway. The Jungrang Stream was selected for this study because the stream was overflowed and the embankment section of the stream was destroyed owing to localized torrential rainfall in 1998 and 2001. Considering 200-year frequency storm, the inlets of the underground discharge channel were located at Seoul City limits, the confluence of Danghyun Stream, Wolgye 1-gyo, and the confluence of Mukdong Stream. The outlets were located at the estuary of Jungrang Stream and rightbank of Banpo Bridge in Han River. The transverse discharge according to the variation of overflow depth at the inlet of underground discharge channel was estimated and the effect of inundation reduction was analyzed. To examine the appropriate scale of the underground discharge channel, the 8 operation methods for the management of outlet discharge were compared considering four rules (only storage, the constant discharge rate, the constant discharge volume, and the mixture of the constant discharge rate and discharge volume). As a result, the effect of inundation reduction was most significantly improved when the inlet was located at the confluence of Danghyun Stream. The appropriate size of underground sluiceway for 200-year frequency storm was studied, and as a result, the appropriate diameters of the underground discharge channel were 12 m in case of only storage(Rule D), 9m in 50% of discharge(Rule E), 8 m in constant discharge volume(Rule F), and 7 m in mixture method(Rule G). This investigation process can be applied to design the underground discharge channel when the inundation damage is significant in coastal area due to embankment overflow. The underground discharge channel in Jungrang Stream can also be used as an underground road to link Seoul City to Uijeongbu City during dry season.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.252-257
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• 2001

To get the basic information for the water quality improvement and control of water resource at Mankyeong river stream, the water quality in four site of main stream and three site of branch stream at the upper stream were investigated mainly from February to August in 2000. The water temperature was affected by depth, flow rate of the water, and air temperature, and ranged 6.4 to $30.8^{\circ}C$. The pH, DO and BOD values of the water was $5.9{\sim}9.7$, $4.6{\sim}14.50\;mg/L$, and $0.1{\sim}11.8\;mg/L$ range, respectively. The content of total nitrogen, $NO_3-N$ and $NH_4-N$ was $1.19{\sim}10.61\;mg/L$, $1.00{\sim}5.93\;mg/L$, and ND $(non\;detected){\sim}2.79$ mg/L, respectively. The concentration of total phosphorus was ND to 1.14 mg/L. The concentration of Cl ion was $3.5{\sim}196.4\;mg/L$. The content of Fe and Mn was $0.002{\sim}0.100\;mg/L$ and $ND{\sim}0.04\;mg/L$, respectively. The contents of heavy metal Cd, Cu, and Zn were $ND{\sim}0.03\;mg/L$, $ND{\sim}0.05\;mg/L$, and $0.001{\sim}0.17\;mg/L$, respectively. Pb was not detected in all the samples. The pH, total nitrogen contents, and total phosphorus content were frequently exceeded the water quality standard for agriculture. The degree of water pollution was very varied by the sampling place. The water quality was generally polluted in the dry season more than in rainy season. The highest level of water pollution observed in the area of Samyea Bridge among the 7 sites.

• Journal of Life Science
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• v.27 no.1
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• pp.100-121
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• 2017

The sexual reproduction of the unicellular green alga Chlamydomonas is reviewed for a comprehensive understanding of the complex processes. The sexual life cycle of C. reinhardtii is distinguished into five main stages: gametogenesis, gamete activation, cell fusion, zygote maturation, and meiosis and germination. Gametogenesis is induced by nitrogen starvation in the environment. C. reinhardtii has two mating types: mating type plus ($mt^+$) and mating type minus ($mt^-$), controlled by a single complex mating type locus ($MT^+$ or $MT^-$) on linkage group VI. In the early gametogenesis agglutinins are synthesized. The $mt^+$ and $mt^-$ agglutinins are encoded by the autosomal genes SAG1 (Sexual AGglutination1) and SAD1 (Sexual ADhesion1), respectively. The agglutinins are responsible for the flagellar adhesion of the two mating type of gametes. The flagellar adhesion initiates a cAMP mediated signal transduction pathways and activates the flagellar tips. In response to the cAMP signal, mating structures between two flagella are activated. The $mt^+$ and $mt^-$ gamete-specific fusion proteins, Fus1 and Hap2/Gcs1, are present on the plasma membrane of the two mating structures. Contact of the two mating structures leads to develop a fertilization tubule forming a cytoplasmic bridge between the two gametes. Upon fusion of nuclei and chloroplasts of $mt^+$ and $mt^-$ cells, the zygotes become zygospores. It is notable that the young zygote shows uniparental inheritance of chloroplast DNA from the $mt^+$ parent and mitochondrial DNA from the $mt^-$ parent. Under the favorable conditions, the zygospores divide meiotically and germinate and then new haploid progenies, vegetative cells, are released.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.105-108
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• 1993

A new devised conductivity meter was used in the rapid and convenient determination of salt contents of soysauce and margarine. The equation $(1){\sim}(5)$ was set up between the electric conductivity (x) for 100 times diluted solution of soysauce and the salt contents (y). y=0.083x-1.253 $(at\;15^{\circ}C)$ (1) y=0.077x-2.062 $(at\;20^{\circ}C)$ (2) y=0.071x-2.686 $(at\;25^{\circ}C)$ (3) y=0.066x-3.153 $(at\;30^{\circ}C)$ (4) y=0.062x-3.522 $(at\;35^{\circ}C)$ (5) y=(-0.001139t+0.0999)x+(-0.126t+0.557) $(temperature\;range;\;15{\sim}35^{\circ}C)$ (6) y=salt contents [%], x=conductivity $[{\mu}{\Omega}^{-1}{\cdot}cm^{-1}]$, $t=temp.\;[^{\circ}C]$. The salt contents could be estimated by the equation $(1){\sim}(6)$ and the measured conductivity. The estimated salt contents agreed with that determined by conventional method within 0.27[%] as salt contents. For margarine, the equation (7) was setup between the conductivity (x) and the salt contents (y) y=0.00266x+0.057 $(at\;20^{\circ}C)$ (7) y=salt contents [%], x=conductivity $[{\mu}{\Omega}^{-1}{\cdot}cm^{-1}]$ The salt contents estimated with the equation (7) and the measured condutivity agreed with that determined by conventional method within 0.028[%] as salt contents. The electric conductivity obtained with conductivity meter could be a valuable criteria salt contents test of Korean soysauce and margarine determining in a few second or minute by handy compact portable meter.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.9-19
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• 2007

This study investigated the interaction between groundwater and stream water systems, which is caused by the artificial weir on streambed, enforcing external stresses on the groundwater system. The study area is in Nami Natural Recreation Woods located in Chungcheongnam-do Geumsan-gun Nami-myeon Geoncheon-ri. In this study both of hydrophysical methods (hydraulic head) and hyrdochemical investigations (pH, EC, major ion analysis) were applied. In order to identify the relationship between each of study results, cross-correlation analysis is performed. From results of hydrophysical methods, water level fluctuation at BH-14, installed by the weir, shows the double-recession pattern much more frequently and much higher amplitudes than the fluctuation at each of other monitoring wells. Using the results by hydrochemical investigations, hydrochemical properties at BH-14 is similar to the hydrochemical characteristics in stream water. To analyze the interrelationships between the results from each of applied methods, cross-correlation analysis was applied. Results from the correlation analyses, water levels at BH-14 and stream weir showed the highest cross-correlation in hydrophysical aspects. On the other hand, the correlation between stream weir and bridge was the highest in hydrochemical aspects. The difference between the results from each of methods is due that the hydrophysical response at BH-14, such as water level, is induced by the pressure propagation-not with mass transfer, but the hydrochemical interaction, caused by mass transport, takes much more times. In conclusion impermeable artificial weir on streambed changes the interfacial condition between the stream and surrounding aquifers. The induced water flux into the groundwater system during flood period make water level at BH-14 increase instantly and groundwater quality higly similar to the quality of stream water. Referred similarities in both of water level and water quality at BH-14 become much higher when water level at weir grow higher.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.09a
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• pp.125-153
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• 2005

It has been widely known that the seismic piezo-cone penetration test (SCPTU) is one of the most useful techniques for investigating the geotechnical characteristics including dynamic soil properties. As the practical applications in Korea, SCPTU was carried out at two sites in Busan and four sites in Incheon, which are mainly composed of alluvial or marine soil deposits. From the SCPTU waveform data obtained from the testing sites, the first arrival times of shear waves were and the corresponding time differences with depth were determined using the cross-over method, and the shear wave velocity profiles (VS) were derived based on the refracted ray path method based on Snell's law and similar to the trend of cone tip resistance (qt) profiles. In Incheon area, the testing depths of SCPTU were deeper than those of conventional down-hole seismic tests. Moreover, for the application of the conventional CPTU to earthquake engineering practices, the correlations between VS and CPTU data were deduced based on the SCPTU results. For the empirical evaluation of VS for all soils together with clays and sands which are classified unambiguously in this study by the soil behavior type classification Index (IC), the authors suggested the VS-CPTU data correlations expressed as a function of four parameters, qt, fs, $\sigma$, v0 and Bq, determined by multiple statistical regression modeling. Despite the incompatible strain levels of the down-hole seismic test during SCPTU and the conventional CPTU, it is shown that the VS-CPTU data correlations for all soils clays and sands suggested in this study is applicable to the preliminary estimation of VS for the Korean deposits and is more reliable than the previous correlations proposed by other researchers.

• Journal of Preventive Medicine and Public Health
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• v.12 no.1
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• pp.13-23
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• 1979

A study was carried out from October 1977 to September 1978 in order to develope health care delively system which will meet to rural area in Korea. For the study objective a model of health care delivery system of Myun (township) area was developed which is adopted the net-work of village health voluntary worker who will play the role of bridge for communication related with health and illness between families or village people and health subcenter, and :he model health care delivery system net-work was set in the area of Soodong Myun, Yangju Gun. which is the rural health demonstration area of Ewha Womans University since 1972. The activities and attitude of 22 village health voluntary workers were observed and analized. during the study period. The results are as follows; 1. For the field activities of village health voluntary workers. a guide line which is described with specific behavioral objectives was developed and used for not only training of the workers but also evaluation of their field activities. 2. During the study period, the number of 971 village people were served primary health care service by village health voluntary worker and the service was classified largely into symptomatic medications (92%) and preventive measures (8%). 3. Comparative percentage of the number of 894 symptomatic cases cared by village health voluntary workers to 5,695 cases of patient treated by Soodong Health Subcenter during the same period was 15.7%. 4. Annual utility rate of village health voluntary worker by Myun total people was 16.1% but utility rate by Rie was varied from 38.2% to 2.8% which shown there were considerable differences in each Rie. In order to settle the village health care service, the obstructive factors of utility should be detected and their counter measure must be taken. 5. As the health need of village people increases, it is expected that the supplement of drug excluding present sit basic drugs is inevitable, but considering the ability of village health voluntary worker, the selection of additional drugs and education, plan should be carefully studied. 6. It is desirable that a financial resource for supplementary purchase of first aid kit, drugs and materials whould be alloted from village public fund like Saemaeul Women's Club fund, which has already practiced in a few villages in the study area. 7. As pointed out by village health voluntary workers, in order to improve the village health, village leaders should be in the center of it and the cooperation of whole village people is a core of healthful village development, and it is reasonable that the health subcenter backs up these voluntary health activities by village people in techniques. 8. It seems effective that a supplementary education for village health voluntary worker be accomplished by a planned education through regular meetings like worker's monthly meeting and irregular post guide when Myun Health Workers can handle the problems found during the round trip of villages. 9. It is desirable that village health voluntary workers, who are recommended by a civil voluntary organization like Saemael Woman's Club, are charged by natural villagc unit, are given a function of village health care service and used through basic education at health subcenter. 10. It is advisable that the village health voluntary worker's service is compensated not by a form of money, but by other way such as an exemption of medical fee of worker herself or her families in health subcenter can be one method. 11. Daily health activities of each village health voluntary worker should be reported to health subcenter by biweekly or monthly in order to get not only for basic data of the program but also for evaluation the program. It is recomandable that the report form should be simple and clear enough for village health voluntary worker to fill it effectively. 12. Village health care service should be developed into a Saemaeul Movement in which village people actively participate. For this, the appointed function of village health voluntary worker should be absorbed into those of living Environment Betterment Section or Family Planning Section of Saemaeul Women's Club or it is desirable that establish a new section, Village Health Promoting Section and make it involve the appointed functions of those sections mentioned above.

• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.409-415
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• 2018

The development of smart devices has brought about significant changes in daily life and one of the most significant changes is the virtual reality zone. Virtual reality is a technology that creates the illusion that a 3D high-resolution image has already been created using a display device just like it does in itself. Unrealized subjects are forced to rely on audiovisual materials, resulting in a decline in the concentration of practices and the quality of classes. It used virtual reality to develop effective teaching materials for radiology students. In order to produce a video clip bridge using virtual reality, a radiology clinic was selected to conduct two exposures from July to September 2017. The video was produced taking into account the radiology and work flow chart and filming was carried out in two separate locations : in the computerized tomography unit and in the LINAC room. Prior to filming the scenario and the filming route were checked in advance to facilitate editing of the video. Modeling and mapping was performed in a PC environment using the Window XP operating system. Using two leading virtual reality camera Gopro Hero, CC pixels were produced using a 4K UHD, Adobe, followed by an 8 megapixel resolution of $3,840{\times}2,160/4,096{\times}2,160$. Total regeneration time was performed in about 5 minutes during the production of using virtual reality to prevent vomiting and dizziness. Currently developed virtual reality radiation and educational contents are being used to secure the market and extend the promotion process to be used by various institutions. The researchers will investigate the satisfaction level of radiation and educational contents using virtual reality and carry out supplementary tasks depending on the results.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.950-955
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• 2007

Non-point source control system which had been designed only for oil-water separation in the fields of oil refinery and garage was upgraded in this research for the removal of runoff pollutants in impervious urban area. Pollutants including oil from driveway and bridge were eliminated by two types of pathway in the system. One is the coalescence mechanism that the oil droplets in the runoff come into contact with each other in the spiral buoyant media surface and form larger coalesced droplets of oil that are carried upstream to the oil layer. The other is the precipitation that solids in runoff were settled by gravity in the system. In this research, coalescing characteristics of oil and water separation were investigated through image analyses, and efficiencies of the non-point source control system were evaluated using dust in driveway and waste engine oil. Media made of high density and high molecular weight polyethylene was indeterminate helical shape and had sleek surface by analysing SEM photographs and BET. Surface area and specific gravity of media which were measured directly were 1,428 $mm^2$ and 45.3 $kg/m^3$ respectively. From the image analyses of the oil droplets photographs which were taken by using microscope, it was proved clearly that the coalescence was the main pathway in the removal of oil from the runoff. Finally, the performances of the non-point source control system filled up with the media were suspended solid $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane extractable materials $71.8\sim94.8%$ respectively.

• The Korean Journal of Pharmacology
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• v.7 no.1
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• pp.53-65
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• 1971

It is well known that diabetes mellitus is associated with metabolic derangements, such as hyper-glycemia, ketosis, glycosuria, and also widespread alterations in the blood vessels, kidneys, eyes, peripheral nerves and heart. It is also recognized that healing of skin wound is delayed in diabetics. In bone, according to Aegerter, osteopenia develops in diabetes mellitus and it is chiefly ascribed to overutilization of protein. Shim claims that total blood flow to the entire skeletal system is approximately 4 to 8 percent of resting cardiac output and blood supply to the skeletal system would be decreased on account of secondary arteriosclerotic changes in the diabetics. An adequate blood supply is an essential factor in the healing process of fracture, and disturbed blood flow, either local or systemic, will invariably delay union of the fragments or the fragments from being fused. As the author has encountered several cases of diabetics in whom healing of fracture was delayed or incomplete, this experimental study was undertaken to elucidate the effects of hyperglycemia and diabetes mellitus on the healing process of fracture. In this experiment adult albino rabbits, weighing about 2 kg. were used and divided into 6 groups. The femur of each animal was fractured surgically, and then the healing process of fracture was periodically checked by radiography at an interval of one week for a period of 6 weeks. Thereafter, all the rabbits were killed to obtain tissue preparation of the femur. The experimental groups were as follows; 1) Control group: Six rabbits sustained a surgical fracture to the femur, without being given any other treatment or drug. 2) Alloxan-treated group: For inducing diabetes, alloxan was given intravenously to 17 rabbits in various dose as follows; to 7 of them 40 mg/kg, to 6 rabbits 80 mg/kg and to 4 rabbits 120 mg/kg of body weight, respectively. 3) Insulin-treated group: Protamine-zinc insulin was injected subcutaneously to each of 6 rabbits in a daily dose of 1 unit per kilogram of body weight. 4) Group treated with insulin after alloxan: Four rabbits were given 80 mg of alloxan once and than 1 unit of insulin per kilogram of body weight daily. Another 5 rabbits were injected 1 unit of insulin per kg of body weight daily following administration of alloxan in a dose of 120 mg/kg. 5) Homotransplantation group: Following intravenous injection of alloxan in a dose of 120 mg/kg, 10 rabbits underwent homotransplantation of a short bone segment to the femur. Five of them were subsequently given 1 unit/kg of insulin daily. 6) Sugar-treated group: six rabbits were fed $15{\sim}20$ gm of sugar daily throughout the period of experiment. The results obtained are summarized as follows; 1. Blood sugar level and damage to the pancreatic islet increased proportionately when alloxan was given to the rabbits in various doses. No appreciable change could be observed in the islets when the blood sugar level was altered by either oral administration of sugar or subcutaneous injection of insulin. 2. Comparing with the control group, healing of fracture was delayed in the alloxan-treated group, while callus formation and periosteal reaction were shown to be more prominent in this group and subsequently, the ultimate osseous tissue formed at the fracture site was significantly smaller in amount and less compact. These findings were more marked as the amount of alloxan increased. 3. Administration of insulin prevented the delay in healing process of fracture in the rabbits with alloxan-induced hyperglycemia. In this case, the course and progression of fracture healing were almost similar to those of control group. 4. Union between the host bone and the fragment transplanted from other rabbit of the same species was more delayed in the group treated with alloxan alone than in the group to which insulin was administered after development of alloxan-induced diabetes. In both groups periosteal new bone developed from the ends of the host bone, above and below the transplanted fragment, and directly fused with failure of periosteal callus to bridge the adjacent ends of the host bone and the transplanted fragment. 5. The healing process of fracture was not inhibited by alteration in blood sugar level when the blood sugar was abnormally increased by excessive sugar intake or lowered by administration of insulin alone. The healing of fracture in these groups progressed similarly as in the control group. In brief summary, it appears that the healing process of fracture would be definitely disturbed in diabetic state brought about by damage to the pancreatic islet. As such an inhibition could be overcome with insulin, it seems that insulin plays an important role in healing of fracture, but alteration in blood sugar level alone does not modify healing process of fracture to significant degree.