• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.228-241
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• 1989

The objectives of this study are to identify flood disasters resulted from heavy rainstorm including earth and stone-debris avalanches and also to develope the scientific data to be needed for establishing the landslide-related disaster prevention countermeasures. For this study, 5 Gun (district) regions including Booyeo, Seochun, Gongju, Boryung, and Chungyang in Chungchongnam-do of the central part of Korea, in which severe landslide damages have been triggered during 3 days from July 21 to July 23, 1987, were investigated. Mostly, landslides having death of human lives triggered from 6 a.m, to 8 a,m. on July 22, and the principal factor was proved to be the continuous heavy rain ; the continuous rainfall of internal region for 3 days measured about 300-673 mm. The structural measures for slope failure prevention countermeasures at the hollow part of upper hillslope should be required. Natural drainage network on slopes should not be disturbed in case of land use alteration, such as a chestnut planting work on hillslopes behind the houses particularly. There are so many problems in recognition of landslide disaster prevention countermeasures including evacuation exercises. More actual education of countermeasures for control of flood and landslide should be put to practice through "civil defense education" and "inhabitants' meeting." In this context, existing Erosion Control Stations of 13 regions established in each Province should not be reduced. The designation criterion and surveying processes of "Landslide Prone Site" published by Forest Administration should also be improved scientifically.

• Journal of the Korean Institute of Gas
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• v.25 no.3
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• pp.27-38
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• 2021

We devised the system to automatically shutdown the boiler and to fundamentally block the harmful gases, including carbon monoxide, into the indoor when the exhaust system swerves: (1) The discharge pressure of the exhaust gas decreases when the exhaust pipe is disconnected. The monitoring system of the exhaust pipe is implemented by measuring the output voltage of APS(Air Pressure Sensor) installed to control the amount of combustion air. (2) The operating software was modified so that when the system recognizes the fault condition of a flue pipe, the boiler control unit displays the fault status on the indoor regulator while shutting down the boiler. In accordance with the ventilation facility standards in the "Rules for Building Equipment Standards" by the Ministry of Land, Infrastructure and Transport, experiments were conducted to ventilate indoor air. When carbon monoxide leaked in worst-case scenario, it was possible to prevent poisoning accidents. However, since 2013, the number of indoor air exchange times has been mitigated from 0.7 to 0.5 times per hour. We observed the concentration exceeding TWA 30 ppm occasionally and thus recommend to reinforce this criterion. In conclusion, if the flue pipe fault detection and the indoor air ventilation system are introduced, carbon monoxide poisoning accidents are expected to decrease significantly. Also when the manufacturing and inspection steps, the correct installation and repair are supplemented with the user's attention in missing flue, it will be served to prevent human casualties from carbon monoxide poisoning.

• Journal of Legislation Research
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• no.54
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• pp.111-154
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• 2018

The protection of fundamental rights of people is a natural duty of a state. Since Constitutional Law declare that a state is obliged to protect the fundamental rights of people obviously, it is reasonable to postulate that a state has a duty to protect every person's right much more positively. Of course, it is true that whereas right of freedom is much more important in modern states, the social right becomes more important currently. Nevertheless, we have no choice but to put an emphasis on the importance of the right of freedom like modern states. Thus states are still bound to try to protect the right of people, specific duty of behavior for the sake of right of freedom belongs to states. In particular, due to the fact that lifts are essential to our comfortable life and the demage from the accident concerning with the lifts is fatal, the strategy for securing the safety of using the lifts is significant to some extent. And because it is true that the experience of UK that put an emphasis on the role of civil actors is meaningful to us, there seems implications for us. Accordingly, it is possible to consider the material components such as the check of safety before installation for the sake of safety enhancement, quality control for lifts parts, specification of check criterion and variation of check cycle etc. and personal ones such as specification of qualification of competent persons, guarantee of competent person's independence, variation of obligator's duty and variation of user's obligation etc. However, as the situation of UK is one thing and that of Korea is another, we don't have to adhere to the policy and the experience of UK strictly. Rather, we had better apply the policy and experience of UK to ours appropriately.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.257-263
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• 2022

In intracavitary radiotherapy, it is essential to verify the correct location of radiation source among quality control items because an incorrect location will irradiate an unnecessary dose to normal tissues. As a basic study of digital line dosimeters, this study fabricated a unit cell dosimeter based on polycrystalline mercury (II) iodide (HgI₂) and compared its performance with a diode. The study result showed that for reproducibility, the relative standard deviation (RSD) was 1.21%, satisfying the RSD evaluation criterion of within 1.5%. Considering linearity, the coefficient of determination R² showed an excellent result of 0.9997. Regarding the evaluation of distance dependence, it showed a similar trend in general with a difference of 0.035 cm for intensity 50% when compared with the inverse square value. This study suggests the applicability of a digital dosimeter for brachytherapy quality control by evaluating the performance of the HgI₂ dosimeter. This study on dosimeter for candidate photoconductor materials can be used as basic data in all areas using radiation.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.111-119
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• 2009

Objectives : To compare the contents of hazardous substances before/after a decoction. Methods : The heavy metal contents before/after a decoction were measured by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) and mercury analyzer. In order to analyze pesticides in 6 samples we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (SO2) were performed by Monier-Williams distillation method. Results : 1. The mean values of heavy metal contents (mg/kg) for the samples were as follows: Samchulkunbi-tang (before decoction - Pb; 1.592, Cd; 0.155, As; 0.055 and Hg; 0.014, after decoction - Pb; 0.036, Cd; 0.002, As; not detected and Hg; 0.001), Yijin-tang (before decoction - Pb; 0.830, Cd; 0.077, As; 0.045 and Hg; 0.015, after decoction - Pb; 0.193, Cd; 0.010, As; not detected and Hg; 0.002), Banhabaikchulcheunma-tang (before decoction - Pb; 0.976, Cd; 0.164, As; 0.167 and Hg; 0.019, after decoction - Pb; 0.031, Cd; 0.003, As; 0.006 and Hg; 0.005), Pyungwi-san (before decoction - Pb; 2.162, Cd; 0.128, As; 0.061 and Hg; 0.018, after decoction - Pb; 0.080, Cd; 0.006, As; not detected and Hg; 0.005), Leejung-tang (before decoction - Pb; 1.480, Cd; 0.294, As; 0.034 and Hg; 0.012, after decoction - Pb; 0.064, Cd; 0.007, As; 0.007 and Hg; 0.002) and Kwibi-tang (before decoction - Pb; 0.907, Cd; 0.193, As; 0.085 and Hg; 0.020, after decoction - Pb; 0.072, Cd; 0.006, As; 0.004 and Hg; 0.002). 2. Contents (mg/kg) of sulfur dioxide ($SO_2$) before a decoction in Banhabaikchulcheunma-tang, Pyungwi-san, Leejung-tang and Kwibi-tang exhibited 3.5, 3.4, 3.8 and 12.4, respectively. However, contents of sulfur dioxide after a decoction in all samples were not detected. 3. Contents (mg/kg) of residual pesticides before/after a decoction in all samples were not detected. Conclusions : These results will be used to establish a criterion of heavy metals, residual pesticides and sulfur dioxide.

• Korean Journal of Biological Psychiatry
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• v.6 no.2
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• pp.240-245
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• 1999

Object : This study was designed to evaluate the effects of olanzapine on the schedule-induced polydipsia(SIP) which is one of animal model of obsessive-compulsive disorder in rats. We administered olanzapine as a serotonin and dopamine blocking agent, fluoxetine as a selective serotonin reuptake inhibitor, and haloperidol for the dopamine antagonist to rats which showed schedule-induced polydipsic behavior. Methods : Spraque-Dawley rats weighing 200-250gm were individually housed and maintained and allowed free access to water. The rats were placed on a restricted diet. To induce polydipsia, rats were placed in the cage where a pellet dispenser automatically dispensed 90mg pellets on a fixed-time 60 seconds(FT-60s) feeding schedule over 150 minute test session per day. Water was available at all times in the cage. After 4 weeks of daily exposure to the FT 60s feeding schedule, experimental rats met a predetermined criterion for polydipsic behavior(greater than 3 times of water per session on average). 5 groups of rats were administered olanzapine(3mg/kg, i.p), olanzapine(10mg/kg, i.p), fluoxetine(5mg/kg, i.p.), haloperidol(0.1mg/kg, i.p.), and vehicle(1cc/kg, i.p.) for 3 weeks. The rats were tested once a week to access schedule induced polydipsic behavior. Water bottles were weighed before and after the 150-minute test session. The chronic effects of administration of experimental drugs on schedule induced polydipsic behavior were analyzed with ANOVA and Scheffe test as a posthoc comparison. In order to measure water consumption in non-polydipsic food-deprived rats, a separate group of rats(N=8) were individually housed and given a single bolus(14.5gm) of food per day which maintained them at their average body weight. Results and Conclusion : The results were as follows ; 1) After 4 weeks of scheduled feeding procedure, the experimental group showed significant differences than the bolus control in the amount of water consumption as compared with their average water intakes for 4 weeks. At the same periods, there were no differences between the experimental group and the bolus control in the body weight. 2) The fluoxetine group showed significant decrease in the amount of water intake over the 3 weeks of drug treatment as compared with their average amount of polydipsic water intakes. The olanzapine 3mg group showed significant decrease in the amount of water intake at 3rd weeks of drug treatment as compared with their average amount of polydipsic water intakes. The olanzapine 10mg group showed significant decrease in the amount of water intake at 2nd and 3rd weeks of drug treatment as compared with their average amount of polydipsic water intakes. However, the haloperidol group and the vehicle control group showed no changes of amounts of water intake for 3 weeks of treatment as compared with their average amount of polydipsic water intakes. 3) The fluoxetine group showed significantly lower amounts of water intake than the haloperidol group at 2nd weeks of drug treatment. And also the fluoxetine group showed significantly lower amounts of water intake than the haloperidol group and the vehicle control at 3rd weeks of drug treatment. The olanzapine 3mg group and the olanzapine 10mg group showed significantly lower amounts of water intake than the haloperidol group and the vehicle control at 3rd weeks of drug treatment. Above findings suggest that the fixed time feeding procedure for schedule-induced polydipsia as an animal model of obsessive compulsive disorder was effective to the evaluation of pharmacological challenge study. The authors assume that the serotonin hypothesis and the serotonin-dopamine interaction hypothesis are preferred to the dopamine hypothesis in the biological etiology of obsessive-compulsive disorder.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.2
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• pp.87-96
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• 2003

The purposes of this study were to find out the optimum intensity of magnetic field where magnetism could promote the activity of osteoblast, and to discover the possibility of clinical application in the areas of dental implants and bone grafts by confirming the effect of clinically increasing bone formation. In this experiment, we used the Neodymium magnet, which had magnetic power six times as strong as the current ones and enabled the resistances against the demagnetization up to 20 to 50 times to be minimized with the size of 1mm in sight. In order to culture cells, a specially designed device was used. It was made to adjust the distance and accordingly to control the intensity of the magnetic field, by placing the cell culture plate in the center with a magnet of 1mm long and thick installed on the both ends. Using MC3T3-E1 cell, a kind of osteoblast-like cell, we cultured, for 24 hours, not only the test group which had been cultured under the magnetic fields with different intensity of 5, 10, 50, 100, 500, and 1000 Gauss, but also the control group excluding the influences of the magnetic field. After observing the cell's form and the density of the culture medium through an inverted microscope, we made a series of proceedings needed for the immunofluoroscence staining, such as fixation, normal serum reaction, primary antibody reaction, and secondary antibody reaction. And with a fluorescence microscope, we observed those-above and compared the frequency of expression of IFG-1 receptor. To make a Western immunoblotting analysis, the cells cultured under the same condition as the above had the procedure of the lysis buffer and the acrylamide gel electrophoresis was carried out. Protein transferred into the nitrocellulose membrane and tested on the primary and the secondary antibody reactions was observed and compared. The results were as follows: When observed through an inverted microscope, the nuclear divisions of the cells under the magnetic field of 10 Gauss were the most active, and the density of the cells could be observed the most enormously. As the result of an immunofluoroscence staining of IGF-1 receptor, the expression of IFG-1 was the most frequently observed under the magnetic field of 10 Gauss. On the other hand, few differences of consideration were made between the test group cultured under the magnetic fields of 5, 500, and 1000 Gauss and the control group. In respect of the expression of IFG-1 receptor, the test group cultured under the magnetic fields of 50 and 100 Gauss were higher than the control group, and lower than that cultured under the magnetic field of 10 Gauss.(p<0.05) According to the Western immunoblotting analysis, the band of IFG-1 receptor which had 85KDa of molecular weight was the darkest. Judging from the above-mentioned results, the growth factor receptor of an osteoblast cell which was an important criterion for the bone formation was increased in maximum under the magnetic field of 10 Gauss. Moreover it was observed that the optimum intensity of magnetic field in which magnetism made the activity of the osteoblast cell increase was about 10 Gauss.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.139-150
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• 2010

In recent years, more generic drug products became available. The current regulation for assessing the bioequivalence of two drug formulations is based on the concept of average bioequivalence. This approach has been indicated to be insufficient for assessing switchability between two drug formulations and US FDA has adopted individual bioequivalence as one of the bioequivalence criterion since 2001. The US FDA recommends that individual bioequivalence be assessed based on $2\;{\times}\;4$ crossover design, while a $2\;{\times}\;3$ crossover design may be used as an alternative design to reduce the length and cost of the study. In this paper, a statistical procedure for assessment of individual bioequivalence under $3\;{\times}\;2$ crossover designs is proposed and some statistical points are discussed with $2\;{\times}\;3$ crossover design and $2\;{\times}\;3$ extra-reference design through simulation studies.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.38-47
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• 1995

The Bioconcentration factor (BCF) is used as an important criterion in the risk assessment of environmental contaminants. Also it can be used as indicator of biomagnification of environmentally hazardous chemicals through food-chain as well as a tool for ranking the bioconcentration potential of the chemicals in the environment. This paper reports the measured BCF value on Chlorothalonil in Carassius auratus(goldfish), under steady state, and examined correlation between the BCF value and the partition coefficient or acute toxicity or physicochemical properties. Carassius auratus(goldfish) was chosen as test organism and test period were 3-day, 5-day. Experimental concentrations were 0.005, 0.01 and 0.05 ppm. Chlorothalonil in fish tissue and in test water were extracted with n-hexane and acetonitrile. GC-ECD was used to detecting and quantitating of Chlorothalonil. Partition coefficient was determined by stir-flask method. $LC_{50}$ was determined on Chlorothalonil. Carbaryl and BPMC. The obtained results were as follows. 1. It was possible to determine short term BCFs of Chlorothalonil through relatively simple procedure in environmental concentrations. 2. $BF_3$ of Chlorothalonil in concentration of 0.005, 0.01 and 0.05 ppm were 2.1866$\pm$0.23446, 3.5269$\pm$0.23517, 10.2045$\pm$0.18053 and BCFs were 6.6543$\pm$0.55257, 6.9774$\pm$0.02500, 23.4576$\pm$2.06884, respectively. 3. Chlorothalonil concentration in fish extract and BCFs of Chlorothalonil were increased as increasing test concentration and prolonging test period. 4. Fate of test-water concentration on Chlorothalonil was greater than that of control-water con-centration. It is considered that greater fate of test-water concentration on Chlorothalonil is due to hydrolyzing nitrile group under the mild condition and substituting chloro group by some aromatic compounds in test water. 5. Determined logP of Chlorothalonil was 2.80. And determined $LC_{50}$ of Chlorothalonil in time of 24, 48, 72 and 96 hr were 0.1684, 0.1402, 0.1400, 0.1352(mg/l) respectively. And $LC_{50}$ of Carbaryl in above times were 19.918, 18.635, 18.466, 18.12(mg/l) respectively. $LC_{50}$ of BPMC were 10.248, 9.166, 9.087, 8.921(mg/l) respectively. 6. It is suggested that the BCF of Carbamates depend on partition coefficients. But BCF of Chlorothalonil, organochlorine pesticide, would be strongly influenced by steric, electronic effect of substituents than partition coefficient.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.2
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• pp.102-108
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• 2013

To understand the relationship of growth and water use efficiency (WUE) between superior and inferior families from open-pollinated progenies of P. densiflora, two families (one superior and one inferior families) in two open-pollinated progeny test sites were selected using volume growth at 26 years. And we compared environmental factors and WUE which was calculated from measured ${\delta}^{13}C$ in the wood. The ${\delta}^{13}C$ change during the last 20 years showed steady decrease and same pattern as WUE in the fertile site, while there was an inverse relationship between ${\delta}^{13}C$ and WUE in poor site, indicating an interaction between gene and environment. The superior family showed higher WUE than inferior family in poor site, indicating efficient stomatal control of the former under water stress. Water use efficiency calculated by carbon isotope composition can be used as a selection criterion for drought tolerance families in open-pollinated progenies of P. densiflora.