• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.105-115
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• 2008

Urbanization results in increased runoff volume and peak flowrate and shortening in time of concentration, which may cause frequent flooding downstream. There are various types of flow retardation methods including detention ponds, retention ponds, and infiltration ponds. In general, hydrologic models to design the detention pond are classified into planning model and design model. This study is comparing and analyzing of planning model to design the detention pond in urban area. Detention ponds data of Disaster Impact Assessment Report on 22 sites were analyzed to investigate proper planning models in this study. From this research, following conclusions are derived, 1) In case of on-line detention pond, Lee model(1991) is the best planning model and similar to real storage volume. 2) In case of off-line detention pond, Abt and Grigg model is much more proper model compared to other models.

• Journal of Ginseng Research
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• v.40 no.3
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• pp.220-228
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• 2016

Background: Among the various ginseng strains, Shizhu ginseng is endemic to China, mainly distributed in Kuandian Manchu Autonomous County (Liaoning Province, China); however, not much is known about the compounds (especially saponins) in Shizhu ginseng. Methods: A rapid, sensitive, and reliable ultra-high performance liquid chromatography coupled with MS/MS (UHPLC-MS/MS) method was developed to separate and identify saponins in Shizhu ginseng. Results: The separation was carried out on a Waters ACQUITY UPLC BEH $C_{18}$ column ($100mm{\times}2.1mm$, $1.7{\mu}m$) with acetonitrile and 0.1% formic acid aqueous solution as the mobile phase under a gradient elution at $40^{\circ}C$. The detection was performed on a Micromass Quattro Micro API mass spectrometer equipped with electrospray ionization source in both positive and negative modes. Under the optimized conditions, a total of 31 saponins were identified or tentatively characterized by comparing retention time and MS data with related literatures and reference substances. Conclusion: The developed UHPLC-MS/MS method was suitable for identifying and characterizing the chemical constituents in Shizhu ginseng, which provided a helpful chemical basis for further research on Shizhu ginseng.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.732-738
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• 2001

This study was attempted to isolate and identify the anticancer compounds from Eucommia ulmoides leaves using a human colon cancer cell line HCT-116. The petroleum ether extracts with anticancer activity was chromatographed on silica gel TLC and finally anticancer compounds was purified by HPLC. Their chemical structures were roughly elucidate by UV-VIS absorption spectral data HPLC elution pattern and FAM/MS spectroscopy. From this study these compounds were suspected to be pheophytin a formed by the removal of $Mg^{2+}$ from chlorophyll a and pyropheophytina formed by the removal of acetate group from pheophytin a respectively. To confirm the anticancer effects against HCT-116 cancer cell petroleum ether extract fractions of column chromatography and fractions separated on TLC were tested. All samples tested including the extract of petroleum ether fractions of column chromatograph and three bands (0.13,0.19,0.25) of TLC appeared to inhibit the growth of HCT-116 cancer cell however especially 0.19 and 0.25 fractions separated on TLC plate revealed the strongest effect. These results suggest that chlorophyll derivatives in Eucommia ulmoides may be potential anticancer agents against a human colon cancer cell HCT-116.

• Journal of the Korea Society of Computer and Information
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• v.21 no.12
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• pp.147-155
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• 2016

In this paper, we propose basic materials for effective education of essential basic nursing skills and empirical base supporting the strengthening of essential basic nursing skills. An investigation was conducted with nursing college students ready for an employment on the relationship between the students' knowledge level of essential basic nursing skills and their satisfaction level against the clinical practice. The collected data were analyzed using descriptive statistics, t-test, one-way ANOVA, scheffē test and Pearson's correlation coefficients. in SPSS WIN 21.0 program. The findings of this study were as follows. 1) The knowledge level of essential basic nursing skills received a score of 88.95. 'Admission management' item received the highest score of 4.96 point on a 5 point scale while 'Retention urinary catheterization' item received the lowest score of 3.06. The higher the difficulty level of essential basic nursing skills was, the lower the knowledge level of it was. 2) The satisfaction against the clinical practice received a score of 3.28. In the clinical practice area, the satisfaction against the curriculum received a score of 3.84, the satisfaction against clinical practice contents a score of 3.39, the satisfaction against clinical practice environment a score of 3.17, the satisfaction against clinical practice time a score of 3.15. There was a significant correlation between the knowledge level of essential basic nursing skills and clinical practice satisfaction. These findings indicate that a systematic education of essential basic nursing skills could improve nursing students' satisfaction against the clinical practice.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.237.2-237.2
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• 2013

ReRAM cell, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of conductive filament in a solid electrolyte [1,2]. Especially, Chalcogenide-based ReRAM have become a promising candidate due to the simple structure, high density and low power operation than other types of ReRAM but the uniformity of switching parameter is undesirable. It is because diffusion of ions from anode to cathode in solid electrolyte layer is random [3]. That is to say, the formation of conductive filament is not go through the same paths in each switching cycle which is one of the major obstacles for performance improvement of ReRAM devices. Therefore, to control of nonuniform conductive filament formation is a key point to achieve a high performance ReRAM. In this paper, we demonstrated the enhanced repeatable bipolar resistive switching memory characteristics by spreading the Ag nanocrystals (Ag NCs) on amorphous GeSe layer compared to the conventional Ag/GeSe/Pt structure without Ag NCs. The Ag NCs and Ag top electrode act as a metal supply source of our devices. Excellent resistive switching memory characteristics were obtained and improvement of voltage distribution was achieved from the Al/Ag NCs/GeSe/Pt structure. At the same time, a stable DC endurance (>100 cycles) and an excellent data retention (>104 sec) properties was found from the Al/Ag NCs/GeSe/ Pt structured ReRAMs.

• Mass Spectrometry Letters
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• v.12 no.4
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• pp.200-205
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• 2021

Polynemoraline C, a pyridocoumarin alkaloid, exhibits anticholinergic, anti-inflammatory, antitumor, and antimicrobial activities. A sensitive analytical method of polynemoraline C in mouse plasma was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Polynemoraline C and ¹³C-caffeine (internal standard) in mouse plasma were extracted using a liquid-liquid extraction method coupled with ethyl acetate. This extraction method resulted in high and reproducible extraction recovery in the range of 73.49%-77.31% with no interfering peaks around the peak retention time of polynemoraline C and ¹³C-caffeine. The standard calibration curves for polynemoraline C were linear over the range of 0.5-200 ng/mL with r² > 0.985. The accuracy, precision, and the stability of the data were within acceptable limits on the FDA guideline. After intravenous and oral administration of polynemoraline C at doses of 5 and 30 mg/kg, respectively, the present method was successfully applied to the pharmacokinetic study of polynemoraline C. Polynemoraline C in mouse plasma showed a multi-exponential elimination pattern with a high volume of distribution values. This compound's absolute oral bioavailability was found to be 17.0%. Polynemoraline C's newly developed LC-MS/MS method can be used for further studies on the efficacy, toxicity, and biopharmaceutics of polynemoraline C, as well as its pharmacokinetic studies.

• The Korea Journal of Herbology
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• v.38 no.5
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• pp.97-103
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• 2023

Objectives : These days many people tend to prefer spicy taste. The purpose of this study was to find out the relationship between prefer spicy and physical symptoms. Methods : We examined the subjective physical condition of patients who visited L/C clinic during the period between January and June 2023 by conducting a survey. The survey was completed voluntarily, and the anonymity and confidentiality of the research data were strictly protected, and it was stated that patients could withdraw at any time if they did not want to participate. Patients who refused to complete the survey and patients with limited capacity to give consent were excluded. The survey took about 10 minutes to complete. We analyzed 248 cases who answered the survey and found that 66 patients had a high spicy preference. Results : As a result, participants with high spicy taste preference tended to have general body symptoms such as fever, sweat, and thirst; digestive symptoms such as belching, constipation, bloody stools, and abdominal distension; genitourinary symptoms such as yellowish urine, urinary retention, white fluor albus, and premenstrual tension; and neuromuscular symptoms such as edema, blepharospasm, and cold hands. Conclusion : People who have general body symptoms, digestive symptoms, genitourinary symptoms and neuromuscular symptoms described above should try to eat as little spicy food as possible and make sure they get a good balance of the five flavors.

• The Korean Journal of Nuclear Medicine
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• v.39 no.4
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• pp.257-262
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• 2005

Purpose: Gastric emptying scan (GES) is usually acquired up to 2 hours. Our study investigated whether a fraction of meal-retention in the stomach at 120 minutes (FR120) was predicted from the data measured for 90 minutes by using non-linear curve fitting. We aimed at saving the delayed imaging by utilizing mathematical models. Materials and Methods: Ninety-six patients underwent GES immediately after taking a boiled egg with 74 MBq (2 mCi) Tc-99m DTPA. The patients were divided into Group I ($T_{1/2}\;{\leq}90\;min$) and Group II ($90\;min). Group I (n=51) had 21 men and 30 women, and Group II (n=45) 15 men and 30 women. There was no significant difference in age and sex between the two groups. Simple exponential, power exponential, and modified power exponential curves were acquired from the measured fraction of meal-retention at each time (0, 15, 30, 45, 60, 75, and 90 min) by non-linear curve fitting ($MATLAB^{\circledR}$ 5.3) and another simple exponential fitting was performed on the fractions at late times (60, 75, and 90 min). A predicted FR120 was calculated from the acquired functional formulas. A correlation coefficient between the measured FR120 and the predicted FR120 was computed ($MedCalc^{\circledR}$ 6.0). Results: Correlation coefficients(r) between the measured FR120 and the predicted FR120 of each mathematical functions were as follows: simple exponential function (Group I: 0.8558, Group II: 0.5982, p<0.0001), power exponential function (Group I: 0.8755, Group II: 0.6008, p<0.0001), modified power exponential function (Group I: 0.8892, Group II: 0.5882, p<0.0001), and simple exponential function at the late times(Group I: 0.9085, Group II: 0.6832, p<0.0001). In all the fitting models, the predicted FR120 were significantly correlated with the measured FR120 in Group I but not in Group II. There was no statistically significant difference in correlation among the 4 mathematical models. Conclusion: In the cases with $T_{1/2}\;{\leq}90\;min$, the predicted FR120 is significantly correlated with the measured FR120. Therefore, FR120 can be predicted from the data measured for 90 minutes by using non-linear curve fitting, saving the delayed imaging after 90 minutes when $T_{1/2}\;{\leq}90\;min$ is ascertained.

• The Korean Journal of Archival Studies
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• no.16
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• pp.97-146
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• 2007

Those days when people used paper to make up and manage all kinds of documents in the process of their jobs are gone now. Today electronic types of documents have replaced paper. Unlike paper documents, electronic ones contribute to the maximum job efficiency with their convenience in production and storage. But they too have some disadvantages; it's difficult to distinguish originals and copies like paper documents; it's not easy to examine if there is a change or damage to the documents; they are also prone to alteration and damage by the external influences in the electronic environment; and electronic documents require enormous amounts of workforce and costs for immediate measures to be taken according to the changes to the S/W and H/W environment. Despite all those weaknesses, however, electronic documents increasingly account for more percentage in the current job environment thanks to their job convenience and efficiency of production costs. Both the government and private sector have made efforts to come up with plans to maximize their advantages and minimize their risks at the same time. One of the methods is the Authorized Retention Center which is described in the study. There are a couple of prerequisites for its smooth operation; they should guarantee the legal validity of electronic documents in the administrative aspects and first secure the reliability and authenticity of electronic documents in the technological aspects. Responding to those needs, the Ministry of Commerce, Industry and Energy and the Korea Institute for Electronic Commerce, which were the two main bodies to drive the Authorized Retention Center project, revised the Electronic Commerce Act and supplemented the provisions to guarantee the legal validity of electronic documents in 2005 and conducted researches on the ways to preserve electronic documents for a long term and secure their reliability, which had been demanded by the users of the center, in 2006. In an attempt to fulfill those goals of the Authorized Retention Center, this study researched technical standard for electronic record information package of the center and applied the ISO 14721 information package model that's the standard for the long-term preservation of digital data. It also suggested a process to produce and manage information package so that there would be the SIP, AIP and DIP metadata features for the production, preservation, and utilization by users points of electronic documents and they could be implemented according to the center's policies. Based on the previous study, the study introduced the flow charts among the production and progress process, application methods and packages of technical standard for electronic record information package at the center and suggested some issues that should be consistently researched in the field of records management based on the results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.269-275
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• 2020

RAM of elements to support weapon systems is conducted at the initial development phase and standard is suggested to accomplish strategy requirement performance from a design spec. Operational availability is a key point of the military's ability to ensure combat readiness and to win the battle. In the weapon system development phase, operational availability is used as a development standard. The military provides ALDT, operation and standby time, which are elements of operational availability. ALDT is a key element of operational availability that must be maintained for combat readiness, as it depends on the aging of a weapon system, maintenance policies and geographical conditions. Operational Availability to be set at the development phase has many differences from the operational availability that is analyzed in the actual operational phase because ALDT is applied as a simple assumption. In the paper, we analyzed ALDT applying the decision tree method through failure data acquired from initial operation. Through this study, we have devised the optimal ALDT setting method to achieve operational availability about operation when the weapons system is unstable.