• Journal of the Korea Institute of Building Construction
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• v.8 no.4
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• pp.115-121
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• 2008

The present study performed low-pressure steam curing with mortar specimens in order to examine the temperature profile and strength development of steam curing in high-strength specimens of 100MPa. In addition, as a basic research to utilize PC products, we examined the effects of curing temperature and time in steam curing cycle on strength development resulting from the hydration of cement within the range of high strength by changing four factors affecting the quality of PC displacement time, peak curing temperature, peak temperature duration, and ascending and descending gradient of temperature - in various patterns, and analyzed the optimal strength development characteristic based on the relation between temperature profile and strength development. With regard to the high-temperature curing characteristic of PC, we performed an experiment on the strength characteristic according to the temperature profile of high-strength mortar, and from the results of the experiment according to curing characteristic, displacement time, peak curing temperature, peak temperature duration, and ascending and descending gradient of temperature, we drew conclusions as follows.

• Clinical and Experimental Pediatrics
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• v.63 no.5
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• pp.171-177
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• 2020

Low-grade epilepsy-associated neuroepithelial tumors (LEATs) are responsible for drug-resistant chronic focal epilepsy, and are the second-most common reason for epilepsy surgery in children. LEATs are extremely responsive to surgical treatment, and therefore epilepsy surgery should be considered as a treatment option for LEATs. However, the optimal time for surgery remains controversial, and surgeries are often delayed. In this review, we reviewed published article on the factors associated with seizure and cognitive outcomes after epilepsy surgery for LEATs in children to help clinicians in their decision whether to pursue epilepsy surgery for LEATs. The achievement of gross total resection may be the most important prognostic factor for seizure freedom. A shorter duration of epilepsy, a younger age at surgery, and extended resection of temporal lobe tumors have also been suggested as favorable prognostic factors in terms of seizure control. Poor cognitive function in children with LEATs is associated with a longer duration of epilepsy and a younger age at seizure onset.

• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.29-35
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• 2020

To manage the non-point source pollution and restore the water circulation, many technologies including infiltration or reservoir systems were installed in the urban area. These facilities have many problems regarding maintenance as their operation period becomes lengthier. The purpose of this study was to estimate the optimal maintenance timing through a long-term load test on the infiltration trench as one of the low impact development techniques. An infiltration trench was installed in the demonstration test facility, and stormwater was manufactured by Manual on installation and operation of non-point pollution management facilities from the Ministry of Environment, Korea and entered into the infiltration trench. Particle size distribution (PSD), suspended solids (SS) removal efficiency, and infiltration rate change tests were performed on inflow and outflow water. In case of the PSD, the maximum particulate size in the outflow decreased from 64 ㎛ to 33 ㎛ as the operating duration elapsed. The SS removal efficiency improved from 97 % to 99 %. The infiltration rate changed from 0.113 L/sec to 0.015 L/sec during the operation duration. The maintenance timing was determined based on the stormwater runoff requirements with these changes in water quality and infiltration rate. The methodologies in this study could be used to estimate the timing of maintenance of other low impact development techniques.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1103-1106
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• 2004

The objective of this study is to induce the design drought rainfall by the methodology of L-moment including testing homogeneity, independence and outlier of the data of annual minimum monthly rainfall in 57 rainfall stations in Korea in terms of consecutive duration for 1, 2, 4, 6, 9 and 12 months. To select appropriate distribution of the data for annual minimum monthy rainfall by rainfall station, the distribution of generalized extreme value (GEV), generalized logistic (GLO) as well as that of generalized pareto (GPA) are applied and the appropriateness of the applied GEV, GLO, and GPA distribution is judged by L-moment ratio diagram and Kolmogorov-Smirnov (K-S) test. As for the annual minimum monthly rainfall measured by rainfall station and that stimulated by Monte Carlo techniques, the parameters of the appropriately selected GEV and GPA distributions are calculated by the methodology of L-moment and the design drought rainfall is induced. Through the comparative analysis of design drought rainfall induced by GEV and GPA distribution by rainfall station, the optimal design drought rainfall by rainfall station is provided.

• Journal of Climate Change Research
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• v.9 no.1
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• pp.31-45
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• 2018

This study implemented the prediction of drought properties (number of drought events, intensity, duration) using the user-oriented systematical procedures of downscaling climate change scenarios based the multiple global climate models (GCMs), AIMS (APCC Integrated Modeling Solution) program. The drought properties were defined and estimated with Effective Drought Index (EDI). The optimal 10 models among 29 GCMs were selected, by the estimation of the spatial and temporal reproducibility about the five climate change indices related with precipitation. In addition, Simple Quantile Mapping (SQM) as the downscaling technique is much better in describing the observed precipitation events than Spatial Disaggregation Quantile Delta Mapping (SDQDM). Even though the procedure was systematically applied, there are still limitations in describing the observed spatial precipitation properties well due to the offset of spatial variability in multi-model ensemble (MME) analysis. As a result, the farther into the future, the duration and the number of drought generation will be decreased, while the intensity of drought will be increased. Regionally, the drought at the central regions of the Korean Peninsula is expected to be mitigated, while that at the southern regions are expected to be severe.

• Physical Therapy Korea
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• v.20 no.2
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• pp.11-19
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• 2013

Delayed onset muscle soreness (DOMS) is a painful condition that arises from exercise-induced muscle damage after unaccustomed physical activities. Various therapeutic interventions have been applied to reduce the intensity and duration of DOMS-related symptoms. Recently, pulsed electromagnetic field (PEMF) intervention has been introduced as an alternative noninvasive treatment for DOMS. This randomized, double-blind, placebo-controlled experiment was conducted to examine the effects of PEMF therapy on DOMS in elbow flexors at 24, 48, and 72 hours after the experimental DOMS induction. Thirty healthy volunteers ($23{\pm}2.4$ yrs, $175{\pm}5.7$ cm, and $74{\pm}7.8$ kg) participated in this study. Each was randomly assigned to a PEMF or placebo group. On the first day, DOMS was induced in the elbow flexors by repeated isokinetic motions at low ($60^{\circ}/s$) and fast ($120^{\circ}/s$) speeds in all subjects. Thereafter, the PEMF group received 15-min daily treatment with a PEMF device. The placebo group received sham treatment of the same duration. Overall, PEMF application was more effective than the sham treatment in reducing the physiological symptoms associated with the DOMS including perceived soreness, median frequency, and electromechanical delay of the surface electromyography. In addition, median frequency and isokinetic peak torque of the PEMF group recovered to the pre-DOMS induction level earlier than the placebo group. In conclusion, this study suggests that PEMF can be applied as a new recovery strategy in reducing DOMS symptoms. Further experiments are required to examine the effect of the PEMF treatment on different types of exercise conditions and to determine the optimal treatment dosage and duration in a real clinical setting.

• The Korean Journal of Pain
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• v.13 no.2
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• pp.182-186
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• 2000

Background: Ropivacaine is a new amide local anesthetics, having therapeutic properties similar to those of bupivacaine but less cardiovascular toxicity and motor blockade. The aim of this study was to evaluate the effects of ropivacaine used in stellate ganglion block (SGB) compared with those of lidocaine or bupivacaine. Methods: This prospective and crossover study performed in twenty patients with sudden sensory neural hearing loss. All patients received three times SGB, in the paratracheal approach using 8 ml of 1% lidocaine, 0.2% bupivacaine, and 0.2% ropivacaine respectively without any orders. Onset time and action duration of Horner's syndrome were observed after each SGB. Results: Onset time of ropivacaine was the middle of the three agents; earlier lidocaine and slower bupivacaine. Lidocaine ($3.0{\pm}1.9$ min), bupivacaine ($4.1{\pm}2.9$ min) and ropivacaine ($3.3{\pm}1.3$ min). But there were no significant differences; Action duration of Horner's syndrome of ropivacaine (223.6?105.2 min) was longer than lidocaine ($134.6{\pm}77.3$ min) and shorter than bupivacaine ($241.2{\pm}115.8$ min). There were significant differences in the action duration of each local anesthetics (P<0.05). There was no critical side effects and temporary foreign body sensation was the most common side effect. Conclusions: We conclude that ropivacaine is a good alternative in SGB instead of lidocaine or bupivacaine. Ropivacaine is a long acting local anesthetic similar to those of bupivacaine with wide margin of safety. However, optimal concentration and volume of ropivacaine in SGB should be studied.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.103-111
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• 1989

The object of this study was to determine the radiation effect on the urinary bladder and to establish the basic data for optimal fraction schedule on the whole abdominal irradiation of the mice. Although radiation damage of the urinary bladder is one of the dose-limiting factor for treatment of lower abdominal cancer, such as uterine cervical or rectal cancer, systematic histopathological study of total dose and recovery duration is very rare, especially in conventional fractionation regimen of clinical use. Authors used 198 mice and analyzed histopathological findings according to total dose(40 & 50GY) and recovery duration(1-15 weeks after completion of irradiation). The results were summarized as follows : 1. No definite difference of radiosensitivity was noted between male and female group. 2. Most of mucosal injuries were recovered within 14 weeks in 40 GY irradiated group. 3. Vascular injury and change of connective tissue were prominent and persisted even mild degree until 15 weeks after completion of irradiation in 50 GY irradiated group. 4. Although follow up duration of this study(105 days) was not enough to compare life span of mice, this study emphasized that precious schedule for treatment planning was necessary for preventing or reducing of later complication.

• Asian Journal for Public Opinion Research
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• v.4 no.4
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• pp.208-245
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• 2017

Background: Attitudes toward breastfeeding in public are one potential barrier to optimal breastfeeding rates and durations. Method: Questions about breastfeeding experience and attitudes toward breastfeeding in public were asked in face-to-face interviews as part of the Korean Academic Multimode Open Survey (KAMOS), May-July, 2017. The response rate was 65.8% (2000 respondents nationwide). Results: A majority of Koreans disagreed (1 or 2 on a 4-point scale) with the statement "Women should not breastfeed their child in open, public places" (53.9%) and agreed (3 or 4 on the 4-part Likert scale) with the statements "I do not feel uncomfortable seeing women breastfeed their child in open, public places" (64.0%) and "Breastfeeding a baby, instead of letting the baby cry, in public places is better for other people" (71.8%). However, despite these generally positive attitudes, the majority also said that they would not breastfeed in public (57.4% of women) or, in the case of men, would not want a close female relative to do so (63.8% of men). Breastfeeding in public was positively correlated with the duration of breastfeeding. People were more positive about breastfeeding in public if they: were parents; did not use formula and breastfeeding a similar amount; had children who had been breastfed in public; were older; were Buddhists rather than Christians. An attempt was made to compare attitudes toward breastfeeding in public and breastfeeding durations internationally, but was inconclusive due to not perfectly comparable data. Conclusion: Our results may be useful in planning public health campaigns in South Korea or future attempts at international comparisons to better understand and address the effect of public opinion regarding breastfeeding in public on breastfeeding rates and durations.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.578-582
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• 1998

In greenhouse studies, control efficacy of water chestnut (Eleocharis Kuroguwai) by Epicoccosorus nematosporus was affected by temperature and dew condition. The appressoria were formed abundantly in the range of 20~28$^{\circ}C$. When stem segments o(30 cm long) of the water chestnut were inoculated with the conidial suspension of E. nematorporus, the mean conidial number attacted amounted to 2,545 conidia. Out of 2545 conidia attacted to the stem pieces, 1,733 (68%) conidia formed appressoria. When these stem pieces were treated for 24 hr at 28$^{\circ}C$ under dew condition, 183,1 (7.2%) lesions were formed 10 days after incubation. The time necessary for the death of the plants was about 24 days. Appressoria were formed at 15~35$^{\circ}C$, but decreased rapidly in their numbers at the temperature lower than 1$0^{\circ}C$ or at 35$^{\circ}C$. The appressoria formation seemed to be depended on the dew duration, which was effective to the lesion formation and plant mortality. Under dew duration of 16~24 hr with temperature range of $25^{\circ}C$ to 3$0^{\circ}C$, the weed control was increased up to 93.9%. There were no differences between the first and second or third dew treatments. A delay of 2 or 3 days in dew treatment did not increase the mortality of plants. For the use of E. nematosporus as a mycoherbicide of water chestnut, a conidial suspension should be applied when dew conditions are kept for 12 hr after inoculation.