• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.13-22
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• 2016

This paper presents development of an appropriate procedure and flow chart to analyze shale gas production data obtained from a multi-fractured horizontal well according to flow characteristics in order to calculate an estimated ultimate recovery. Also, the technical considerations were proposed when a rate transient analysis was performed with field production data occurred to only $1^{st}$ transient flow. If production data show the $1^{st}$ transient flow from log-log and square root time plot analysis, production forecasting must be performed by applying different method as before and after of the end of $1^{st}$ linear flow. It is estimated by an area of stimulated reservoir volume which can be calculated from analysis results of micro-seismic data. If there are no bottomhole pressure data or micro-seismic data, an empirical decline curve method can be used to forecast production performance. If production period is relatively short, an accuracy of production data analysis could be improved by analyzing except the early production data, if it is necessary, after evaluating appropriation with near well data. Also, because over- or under-estimation for stimulated reservoir volume could take place according to analysis method or analyzer's own mind, it is necessary to recalculate it with fracture modeling, reservoir simulation and rate transient analysis, if it is necessary, after adequacy evaluation for fracture stage, injection volume of fracture fluid and productivity of producers.

• Journal of the Korea Institute of Building Construction
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• v.10 no.2
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• pp.41-50
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• 2010

This study presented a model that can enable a reliability analysis for the repair and replacement cycle of a building by using background repair and replacement data and expert opinion as foundation data and applying Monte Carlo Simulation. The presented model offers the time of the repair and replacement of building elements for the period of a year, and supports the prediction of repair and replacement and expenses demand in advance while planning the maintenance of a building. In addition, the model will significantly reduce the risks to the building owner with regard to maintenance decisions. In addition, when a person in charge of the maintenance of large-scale building assets is having difficulties making decisions regarding the repair and replacement of existing building elements due to a lack of background data to support a long-term policy on the repair and replacement requirements, an engineering solution that can ensure the adequacy of this is provided. In summary, it can be largely divided into three study results. First, a method of estimating the repair and replacement cycle that can deal with the development of a construction system was developed. Second, a probabilistic methodology that can quantify the risk of the repair and replacement cycle was proposed. Third, the proposed model can be used as a means of supporting designer and constructor in making decisions for the life cycle plan of a building during a construction project.

• Korean Security Journal
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• no.16
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• pp.47-64
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• 2008

The purpose of this study is to develop the measurement of security needs satisfaction from users of electronic security system, to verify its validity and reliability, and by applying them, to examine the effects between the communities using this system. In 2008, the users of electronic security system in big cities in Seoul(Yong-San, Jong-Lo) and Gyung-Gi Do(Su-Won) for their convenience stores, jewelry shops, communication services, banks, government and public offices, etc. were arranged for a population and 262 of them were used for the final analysis by purposive sampling. This study yields following results. First, the validity of security need satisfaction from users of electronic security system is very high, which means the explanatory adequacy of environmental security need is the highest. Second, the reliability of security need satisfaction from users of electronic security system is very high, in which the reliability value(Cronbach's $\alpha$) of internal consistency is over .765. Third, the security need of electronic security system has the most effects on the group of bank workers. That is, through a close cooperative system between the bank and the service of electronic security system, the more keeping satisfied the environmental, bodily, physical security needs are, the less the in security of this group has. Informational security need has the most effects on convenient store group. It means the service companies of electronic security system offer more services at dawn time and make or supply all sorts of visual information system, which reduces insecurity of the convenient store group.

• Journal of Chest Surgery
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• v.32 no.12
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• pp.1065-1077
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• 1999

Background : Ventricular assist devices(VADs) are being used for patients in postcvardiotomy cardiogenic shock status bridge to cardiac transplant settings and in post-myocardial infarction cardiogenic shock. The VAD which was developed at the Deparment of medical engineering in Dankook University College of Medicine was a pneumatically driven device and can maintain pulsatile flow. The goal of this study is to develop animal experimental models using the VAD and to clarify the reliability and hemodynamic property adequacy of end organ perfusion durability and severity of thrombotic-hemolytic tendency of the device. Material and Method : The pneumatic VAD was applied to 8 adult female lambs, We examined some hemodynamic parameters such as arterial blood pressure pulmonary capillary wedge pressure(pcwp) pulmonary artery pressure(PAP) left atrial pressure hour urine output cardiac index VAD flow EKG to determine the reliability of the VAD and hemodynamic compatibility of the experimental animals within 24 hours of experiment. We also observed the end organ perfusion durability of the VAD and thrombotic-hemolytic property of the VAD after 24 hours of VAD insertion. Result: We could monitor all hemodynamic parameters including pcwp PAP cardiac index EKG, adn hour urine as true clinical settings. We observed that the reliability of the VAD was excellent and the hemodynamic property of the experimental animal and end organ perfusion were adequate within 24 hours of experiment. In four lambs surviving 24 hours after insertion the reliability of the VAD and end organ perfusion were excellent and no thrombotic-hemolytic tendency was noted. However after 15 days of experiment the diaphragm of the VAD was torn and it was recommende that the durability of the VAD should be extended. Conclusion : e conclude that the pneumatic VAD developed at Dankook University Biomedical Engineering has good hemodynamic property and low thromboembolic tendency and presents adequate end organ perfusion but we noted that the durability of the device should be expanded further. It will be possible to do more reliable experiment in the future according to the animal experimental method developed in this study especially with the heart failure models.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.367-380
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• 2013

In this study, sub-indicators, and thematic mid-indexes to evaluate the water use characteristics were selected through historical data analysis and factor analysis, and consisted of the subject approach framework. And the integrated index was developed to evaluate water use characteristics of the watershed. Using developed index, the water use characteristics were assessed for 812 standard basins with the exception for North Korea using data of 1990 to 2007 from the relevant agencies. A sensitivity analysis is conducted for this study to determine the proper way through various normalization and weighting methods. To increase the objectivity of developed index, the history of the damage indicators are excluded in the analysis. In addition, in order to ensure its reliability, results from index with and without consideration of the damage history were compared. Also, the index is also applied to real data for 2008 Gangwon region to verify its field applicability. Through the validation process this index confirmed the adequacy for the indicators selection and calculation method. The results of this study were analyzed based on the spatial and time vulnerability of the basin's water use, which can be applied to various parts such as priority decision-making for water business or policy, mitigations for the vulnerable components of the basin, and supporting measures to establishment by providing relevant information about it.

• Information Systems Review
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• v.17 no.3
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• pp.159-181
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• 2015

This study proposes a comprehensive model of purchasing intention of customers in agricultural products online shopping malls. In this study, we derived the factors through the literature reviews and logical reasoning and classified the factors as a business point of view, an information systems point of view and an agricultural characteristics point of view, and developed the integrated research model which is the factors affect purchase intentions by mediating trust and the perceived usefulness. A total of 329 samples of a valid survey data from the members of small agricultural online shopping malls were collected and the research model was empirically analyzed by a confirmatory factor analysis and path analyses using structural equation modeling with the data. The results show that the product quality and the service quality of the business point of view have effects on the trust, however the price adequacy and entertainment have no effect on the trust and the perceived usefulness respectively, also the advertising exposure has no effect on the trust but it has an effect on the purchase intention directly. The information quality and the ease of use of the information systems point of view have an effect on the trust and perceived usefulness. At last, the seasonal product of the agricultural characteristics point of view has effects on perceived usefulness but the regional brand has no effect on the trust. The results of this study provide strategic implications for successful development and operation of agricultural products online shopping malls.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.588-592
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• 2014

Under optimized condition mild pressure in combination with specific temperature for heat treatment transform the 6-gingerol into 6-shogaol. The purpose of this study was to optimize the conditions used for heat treatment under pressure for increasing 6-shogaol content in ginger (Zingiber officinale Roscoe). A central composite experimental design was used to evaluate the effects of application temperature ($70-130^{\circ}C$) and temperature-holding time (95-265 min) on the transformation of 6-shogaol. The experimental values were shown to be in significantly good agreement with the predicted values (adjusted determination coefficient, $R^2{_{Adj}}=0.9857$). 6-Shogaol content increased as the application temperature and temperature-holding time increased. By analyzing the response surface plots, the optimum conditions of heat treatment (temperature and time) for increasing 6-shogaol content were found to be $127^{\circ}C$ and 109 min, respectively. Under these optimal conditions, the predicted 6-shogaol content was 3.98 mg/g dried ginger. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation data.

• Journal of Biomedical Engineering Research
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• v.19 no.2
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• pp.163-170
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• 1998

The ultimate goal of total artificial heart is permanent substitute for a failed heart in a patient without any other therapeutic modality. Until now, infection has been the main problem related to the mechanical circulatory support system. The best way to solve this catastrophic complication and to improve the quality of life of TAH patients in terms of tethering must be implantation of TAH totally. The EH-TAH has been developed in NCVC from 1987 for this purpose. The system consists of an energy converter and pumps, which are designed to be placed in abdomen and pericardial space separately for a good anatomical fit. To evaluate the anatomical fit and hemodynamic performance of the EH-TAH, in vivo test was done. General condition of the animal and hemodynamic status had been stable until the TAH stopped on the 11th pumping day. The estimated cardiac output was about 7.7L/min. The values of mean aortic pressure, left and right atrial pressure were 93$\pm$10, 19$\pm$3 and 15$\pm$4 mmHg, respectively. The correlation coefficient between left and right atrial pressure was 0.96, which represents the dynamic function of the interatrial shunt in controlling left-right imbalance of cardiac output. During pumping days, the temperature on the surface of actuator had been maintained at 39.7$\pm$0.4$^{\circ}C$, less than 1$^{\circ}C$ higher than the rectal temperature. The TAH stopped on the 11th day due to mechanical problems. We concluded that the EH-TAH possessed satisfactory basic performance including anatomic fit and hemodynamic adequacy, although there were several mechanical problems to be solved yet.

• Journal of Nutrition and Health
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• v.38 no.6
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• pp.419-431
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• 2005

The prevalence of atopic dermatitis (AD) continues to increase in the industrialized countries related to Western lifestyle and dietary patterns. The purpose of this study was to evaluate the nutritional status, dietary patterns and dietary quality of AD patients. AD patients (n=50) and gender age matched healthy control (HC) were studied in case-control clinical trail. Preference and frequencies of consumption for 98 foods were estimated by questionnaires. Dietary pattern, current nutrients intake, and dietary quality were evaluated by the 3-day food records. As a result, anthropometric measurements from HC and AD patients were not significantly different. AD patients had significantly lower preference for buckwheat, some fishes (shellfish, flatfish, salmon), egg yolk, some vegetables (onion, garlic, Chinese-cabbage, radish, pepper, mushroom), coffee, and snack than those of HC had (p<0.05). AD patients had significantly lower frequency for pea, some fishes (shellfish, herring, flatfish, salmon, codfish), egg, some vegetables (spinach, pumpkin, mushroom), margarine/butter, nuts, coffee and apple juice, fried chicken, coke than those of HC had (p<0.05). The intake of vitamin $B_1$, vitamin $B_2$ (p<0.05) and vitamin E (p<0.001) of AD patients were significantly lower than those of HC. The intake for Ca and Zn of AD patients were remarkably lower than RDA for each nutrient. Moreover, AD patients' index of nutritional quality (INQ) and nutrient adequacy ratio (NAR) of vitamin E, vitamin $B_1$, vitamin $B_2$ were lower than those of HC. AD patients' dietary quality including dietary diversity score (DDS), dietary variety score (DVS), DMGFV (dairy, meat, grain, fruit, vegetable), dietary quality index (DQI) was poor. This results indicate that atopic dermatitis patients had significantly different food preference and food frequency when these were compared with those of healthy people. The dietary diversity, dietary variety and dietary quality of atopic dermatitis patients were very limited.

• Journal of Korean Neurosurgical Society
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• v.29 no.4
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• pp.536-542
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• 2000

Objective : This study was performed to evaluate the relationships among intracranial pressure(ICP), cerebral perfusion pressure(CPP), and cerebral arteriovenous oxygen difference($AVDO_2$) which were used as parameters of adequacy of cerebral blood flow to support cerebral metabolism after severe head injury and also to examine the association between delayed cerebral infarction and outcome. Material and Method : The authors studied the ICP, CPP and $AVDO_2$ before and after treatment on 34 head-injured patients from June 1996 to December 1997 and examined the association with the change of an ICP, CPP and $AVDO_2$ following treatment and the development of delayed cerebral infarction. Sixteen patients underwent craniotomy for hematoma evacuation and eighteen patients received mannitol to decrease ICP. Results : The development of delayed cerebral infarction was demonstrated in 3(42.9%) out of 7 patients in no improvement group and 13(48.1%) out of 27 patients in improvement group with an increased ICP following treatment. Also, the development of delayed cerebral infarction was demonstrated in 8(50%) out of 16 patients in no improvement group and 8(44.4%) out of 18 patients in improvement group with a decreased CPP following treatment. The association with changes of ICP and CPP following treatment and development of delayed cerebral infarction was not statistically significant(p>0.01). However, 11(78.6%) out of 14 patients who demonstrated an increase in $AVDO_2$ and 5(25%) out of 20 patients who demonstrated a decrease in $AVDO_2$ following treatment developed delayed cerebral infarction. No improvement(reduction) in $AVDO_2$ following treatment was significantly associated with the development of delayed cerebral infarction(p<0.01). All of 16 patients with delayed cerebral infarction showed poor prognosis. Conlcusion : The change of $AVDO_2$ rather than those of ICP and CPP was considered more important factor for the development of the delayed cerebral infarction and poor outcome.