• Korean Journal of Artificial Intelligence
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• v.11 no.2
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• pp.1-6
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• 2023

This paper presents a comprehensive scheme for assessing the importance of multiple microgrids (MGs) network that includes distributed energy resources (DERs), renewable energy systems (RESs), and energy storage system (ESS) facilities. Due to the uncertainty of severe weather, large-scale cascading failures are inevitable in energy networks. making the assessment of the structural vulnerability of the energy network an attractive research theme. This attention has led to the identification of the importance of measuring energy nodes. In multiple MG networks, the energy nodes are regarded as one MG. This paper presents a modified PageRank algorithm to assess the importance of MGs that include multiple DERs and ESS. With the importance rank order list of the multiple MG networks, the core MG (or node) of power production and consumption can be identified. Identifying such an MG is useful in preventing cascading failures by distributing the concentration on the core node, while increasing the effective link connection of the energy flow and energy trade. This scheme can be applied to identify the most profitable MG in the energy trade market so that the deployment operation of the MG connection can be decided to increase the effectiveness of energy usages. By identifying the important MG nodes in the network, it can help improve the resilience and robustness of the power grid system against large-scale cascading failures and other unexpected events. The proposed algorithm can point out which MG node is important in the MGs power grid network and thus, it could prevent the cascading failure by distributing the important MG node's role to other MG nodes.

• Journal of The Korean Association of Information Education
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• v.22 no.4
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• pp.409-417
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• 2018

There are unplugged computer science activities for elementary school students to learn the concept of the Internet. However, these activities are not enough to teach the concept of the Web because they focus on teaching how the Internet works. Since the Web is the core technology of the Third Industrial Revolution, it needs to be understood as a basic common sense. In this paper, we developed an unplugged activity to understand the PageRank algorithm which is closely related to the web. The experimental results show that our unplugged activities behave similarly to the PageRank algorithm.

• The Korean Journal of Applied Statistics
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• v.29 no.4
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• pp.613-625
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• 2016

The development of technology has changed the world drastically. Patent data analysis helps to understand modern technology trends and predict prospective future technology. In this paper, we analyze the patent citation network using the USPTO data between 1985 and 2012 to identify technology trends. We use network centrality measures that include a PageRank algorithm to find core technologies and identify groups of technology with similar properties with statistical network models.

• The Korean Journal of Rehabilitation Nursing
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• v.4 no.1
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• pp.94-104
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• 2001

The purpose of this study was to analysis of nursing interventions performed by the ICU nurses to the patients with cerebrovascular disorder practically from one university hospital in Seoul. The data were collected from 15 nurses with 86 cerebrovascular disorder cases from one ICU with the questionaire to write frequency of nursing care done by the surveyee from May, 2, 2000 to July, 3, 2000 and the list of 66 nursing interventions selected out of 433 NIC(Nursing Interventions Classification) of Iowa University which were translated into Korean (44 items) and core nursing interventions by ICU nurses (22 items; KIm, Su-Jin, 1997). The data were analysed with SPSS program. The results are as follow : 1. The most frequently used nursing interventions were vital sign monitoring, fall prevention, cerebral edema management, dysreflexia management, neurologic monitoring, cardiac care, communication enhancement, technology management, bed rest care, respiratory monitoring in rank. 2. The most frequently used nursing intervention domains were 'Physiological : Complex', 'Physiological : basic', 'Behavior', 'Safty', 'Health system' in rank. In the domain of physiological : basic, the most frequently used nursing interventions were bed rest care, urinary elimination management, tube care : urinary, physical restraints in rank. In the domain of physiological : complex, the most frequently used nursing interventions were cerebral edema management, dysreflexia management, neurologic monitoring, cardiac care in rank. In the domain of behavior, the most frequently used nursing interventions were communication enhancement, touch, active listening in rank. In the domain of safty, the most frequently used nursing interventions were vital sign monitoring, fall prevention in rank. In the domain of health system, the most frequently used nursing interventions were technology management, specimen management in rank. 3. some difference of the frequency practicing the nursing interventions according to the shift of duties was found. For example, medication administration was common at day duty, touch was practiced at evening duty, temperature regulation was performed.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.8 no.1
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• pp.31-36
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• 2010

Purpose : The purpose of this study was to investigate the effects of core exercise on the static balance for females in their twenties. Methods : The core exercise program was conducted 3 times per week for 4 weeks. The result is based on the analysis of measuring static balance before and after the core exercise program. By using the GOOD BALANCE system, the assessment of the static balance ability was made before and after the exercise of 6 postures: normal standing, one left leg?and one right leg standing with eyes open and closed respectively. For each case, the experimental data were obtained in 3 items: mean X speed, mean Y speed, and velocity moment. Statistical analysis was performed using SPSS/Win(10.0) version and Willcoxon signed rank test. Results : From the result of this study, we found that mean X speed, mean Y speed and velocity moment of total postures significantly increased after the 4 week program of core exercises. Conclusion : These finding indicate that core exercises could be beneficial to females in their twenties due to the effect of increasing static balance.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1086-1092
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• 2012

In this study, kinetic studies and analysis of the produced syngas were conducted for low rank coal gasification under $CO_2$ atmosphere. 6 coals were analyzed to measure amount of sulfur and ash by proximate and ultimate analyses. And then they were analyzed to select suitable sample by using Thermogravimetric analyzer (TGA). Selected coal sample Samhwa was mixed with catalysts. Mixed samples with catalysts were used to get activation energy under $CO_2$ atmosphere by using Kissinger's method and shrinking core model (SCM). Also, analysis of produced syngas was performed by Gas Chromatography (GC). In this experiment, activation of the $K_2CO_3$ was the best performance, and result of the analysis of the syngas showed similar trend with result of the activation energy.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.99-106
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• 2017

In this study, mixed catalytic char gasification of Indonesia low-rank coal Kideco was investigated under nitrogen atmosphere and isothermal conditions at a fixed reactor. The effects of the temperature were investigated at various temperature (700, 750, 800, $850^{\circ}C$). The effects of blend ratio of catalysts ($K_2CO_3$, Ni) were investigated with different blend ratios (1:9, 3:7, 5:5, 7:3 and 9:1). The sample was prepared by mixing with $K_2CO_3$ physically and by ionexchange method with Ni. The data from thermogravimetric analyzer and gas chromatography were applied to four gassolid reaction kinetic models including shrinking core model, volumetric reaction model, random pore model and modified volumetric reaction model.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.167-180
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• 2006

Websites in the Internet are uncontrollable domain and various contents in websites lead people's activities and thoughts and new business paradigms for the future. These phenomena are from expanding the social network based on the endless growth of information technology. Websites are composed with many of links and communicating and expanding their virtual area by links, inbound, outbound, onsite, and of offsite links. Research and practice in digital information on the web have focused on finding and measuring artifacts, factors and attributes of web structure and contents from the perspective that information is a resource and property of products and services. Websites links is one of the core artifacts for understanding the virtual area. This study identifies the role of web link structure and webpage keyword as artifacts and examines their relationships by webpage rank by a minimal hub as performance in the business websites that are serving tourism information. Discovering relationships of links provides managerial insights on organizations virtual activities and systematic understandings about digitalized organizational information in the information use environment.

• Journal of Industrial Convergence
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• v.15 no.2
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• pp.1-6
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• 2017

This paper illustrates key features of an enterprise employment simulation which integrates a system dynamic feedback model with a cost-effectiveness optimisation capability utilising genetic algorithms. Its core is a 3-dimensional array structure tracking staff numbers by rank, by time-in-rank, by years-of-service. The resultant model, which could readily be adapted to non-Defence use, can identify, given user specification of any mix of employment rules, the likely patterns of employment behaviour including: resultant time-in-rank and years-of-service profiles; ability of a Unit to fill all positions to target strength; ability to fill promotional positions within normal rules for substantive promotion; need to fill promotional positions using rules for temporary promotion or transfer from outside; necessary recruitment pattern to sustain target strength.

• Journal of Preventive Medicine and Public Health
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• v.53 no.5
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• pp.362-370
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• 2020

Objectives: Despite greater access to training positions and the presence of more women in emergency medicine, it has remained a men-dominated field. This study aims to identify the key issues causing the gender gap in Korea and establish measures to overcome them. Methods: Using the annual statistical reports of the National Emergency Medical Center and data published on the Korean Society of Emergency Medicine website, cases that listed the current status and positions of members in its organization and its committees were analyzed. Secondary analysis was conducted using data from the 2015 Korean Society of Emergency Survey that included physicians' demographics, academic ranking, years of experience, clinical work hours, training and board certification, core faculty status, position, and salaries. Results: As of September 2019, women account for only 12.7% of the total number of emergency physicians (EP) in Korea; of 119 chair/vice-chair academic positions, women represented only 9.2%. Women EP were more often assistant professors and fellowship-trained, with fewer in core faculty. However, they worked the same numbers of clinical hours as their men counterparts. The median annual salary of women EP was less than that of men EP after adjusting for academic hospital rank, clinical hours, and core faculty status. Conclusions: A gender gap still exists among Korean EP, and women earn less than men regardless of their rank, clinical hours, or training. Future studies should evaluate more data and develop system-wide practices to eliminate gender disparities.