• Journal of Advanced Navigation Technology
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• v.6 no.1
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• pp.77-83
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• 2002

The emergence of Bluetooth as a radio interface scheme has allowed electronic devices to be instantly interconnected as ad-hoc networks. These short range ad-hoc wireless networks are called piconets, operated in the unlicensed 2.45 GHz ISM(Industrial, Scientific, Medical) band where up to eight devices may be used to configure single or overlapping piconets. In this paper, we have simulated the PER(Packet Error Rate), the ratio of received packet and payload BER(Bit Error Rate) of piconet with packet types of Bluetooth ACL/SCO(Asynchronous Connection Less/Synchronous Connection Oriented) link over wireless ad-hoc environment. The Rayleigh fading effects are considered as channel model, and the simulation results are based on the baseband model of Bluetooth specification. From the simulation results, the PER and the throughput of Bluetooth piconet are sensibly affected by the packet type of ACL/SCO link.

• Journal of Elementary Mathematics Education in Korea
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• v.19 no.4
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• pp.563-588
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• 2015

In elementary school, didactical transposition is inevitable due to several reasons. In mathematics, addition and multiplication are taught as binary operations, subtraction and division are taught as unary operations. But in elementary school, we try to teach all the four operations as binary operations by didactical transposition. In 'Mastering' the concepts of the four operations, the way of concept introduction is dealt importantantly. So it is different from understanding the four operations. In this study, we analyzed the four operations of natural numbers and fractions from two perspectives: concept understanding (how to introduce concepts and how to choose an operation) and connection between the operations. As a result, following implications were obtained. In division of fractions, students attempted a connection with multiplication of fractions right away without choosing an operation, based on the situation. Also, to understand division of fractions itself, integrate division of fractions presented from the second semester of the fifth grade to the first semester of the sixth grade are needed. In addition, this result can be useful in the future textbook development.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.29-36
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• 2014

The purpose of this study is to improve the Generic Agricultural Systems Simulator (GASS) which can simulate various rural systems based on object-oriented model. GASS provides the configuration platform of various system components to simplify integrated agricultural system models such as irrigation systems for rice farming. The new connection and communication modules of GASS improve applicability for modelling diverse systems. The geometric connection of GASS replaces topological connection, and communication protocols expand to analyze not only homogeneous system but also heterogeneous system. In this paper, we applied GASS2 to simulate the water heights of linked tanks and the simulation outputs were verified through comparing with analytical solutions of differential equations. The two new modules make it possible to analyze the 4-tank problem which includes topological and heterogenous issues with GASS2.

• Steel and Composite Structures
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• v.10 no.3
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• pp.261-279
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• 2010

Generally, a box tube, which is used for an existing square CFT structure, is made by welding four plates. The manufacturing efficiency of this steel tube is poor, and it also needs special welding technology to weld its internal diaphragm and the through diaphragm. Therefore, an interior-anchor-type square steel tube was developed using the method of cold-forming thin plates to prevent welding of the stress concentration position, and to maximize the section efficiency. And, considering of the flow of beam flange load, the efficiency of erection and the weldability of the diaphragm to thin walled steel column, the external diaphragm connection was selected as the suitable type for the welded built-up square CFT column to beam connection. And, an analytical study and tests were conducted to evaluate the structural performance of the suggested connection details and to verify the suggested equations for the connection details. Through this study, the composite effect of the internal anchor to concrete, the resistance and stress distribution of the connections before and after the existing column is welded to the beam, the effective location of welding in connection were analyzed.

• Journal of Integrative Natural Science
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• v.7 no.1
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• pp.50-56
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• 2014

To explore effects on each the emotional awareness, emotional expression, emotional empathy, and emotional regulation, of the sub-factors of the child's emotional intelligence, to mural preference, emotion cultivation, and community connection, the hierarchical multiple regression analyses are performed(as in Table 1, 2, and 3). As the results, we found the following facts. Children's mural preference, emotion cultivation, and community connection were expressed by the following equations in order, respectively. Mural Preference = $.170{\times}$[Emotional Awareness](t=2.118, $p=.036^*$) - $.025{\times}$[Emotional Expression](t=-.275, p=.783) + $.088{\times}$[Emotional Empathy](t=.938, p=.350) + $.139{\times}$[Emotional Regulation] (t=1.529, p=.128). Mural Emotion Cultivation = $-.021{\times}$[Emotional Awareness](t=-.294, p=.769) - $.205{\times}$[Emotional Expression](t=-2.573, $p=.011^*$) + $.265{\times}$[Emotional Empathy](t=3.156, $p=.002^*$) + $.192{\times}$[Emotional Regulation](t=2.361, $p=.019^*$). Mural Community Connection = $-.001{\times}$[Emotional Awareness](t=-.007, p=.995) - $.132{\times}$[Emotional Expression](t=-1.478, p=.141) + $.172{\times}$[Emotional Empathy](t=1.732, $p=.027^*$) + $.098{\times}$[Emotional Regulation](t=1.072, p=.285).

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.198-205
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• 2022

Along with a variety of coding education, physical computing education for controlling various sensors is being actively conducted for elementary, middle, and high school students in line with the era of the fourth industrial revolution. A problem with physical computing education using Arduino is pin connection errors between Arduino and various sensors. Most of the students who come into contact with the Arduino for the first time often do not know the purpose of the Arduino pin and the connection position of the pin. Also, hardware built with incorrect pin connections to the Arduino board often does not work properly. If this case continues, students will lose interest in coding education. Therefore, in this paper, we implemented an augmented reality application that informs the connection process of the Arduino board and the sensor during physical computing coding education using Arduino, and designed and implemented educational content for the Arduino pin position and connection process. First, we explain the role of the Arduino board and the sensor and the location of the pins. After that, the students run the educational augmented reality educational content using their smartphones and check the correct pin connection process between the Arduino and the sensor. In the physical computing education, augmented reality content is used to increase the understanding and immersion of the class. It is expected that the educational effect will also increase by inducing fun and interest in physical computing coding education.

• Clinical and Experimental Pediatrics
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• v.61 no.7
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• pp.210-216
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• 2018

Purpose: The present study aimed to evaluate progression and prognosis according to the palliation method used in neonates and early infants aged 3 months or younger who were diagnosed with pulmonary atresia with ventricular septal defect (PA VSD) or tetralogy of Fallot (TOF) with severe pulmonary stenosis (PS) in a single tertiary hospital over a period of 12 years. Methods: Twenty with PA VSD and 9 with TOF and severe PS needed initial palliation. Reintervention after initial palliation, complete repair, and progress were reviewed retrospectively. Results: Among 29 patients, 14 patients underwent right ventricle to pulmonary artery (RV-PA) connection, 11 palliative BT shunt, 2 central shunt, and 2 ductal stent insertion. Median age at the initial palliation was 13 days (1-98 days). Additional procedure for pulmonary blood flow was required in 5 patients; 4 additional BT shunt operations and 1 RV-PA connection. There were 2 early deaths among patients with RV-PA connection, one from RV failure and the other from severe infection. Finally, 25 patients (86%) had a complete repair. Median age of total correction was 12 months (range, 2-31 months). At last follow-up, 2 patients had required reintervention after total correction; 1 conduit replacement and 1 right ventricular outflow tract (RVOT) patch enlargements. Conclusion: For initial palliation of patients with PA VSD or TOF with severe PS, not only shunt operation but also RV-PA connection approach can provide an acceptable outcome. To select the most proper surgical strategy, we recommend thorough evaluation of cardiac anomalies such as RVOT and PA morphologies and consideration of the patient's condition.

• Journal of Korean Library and Information Science Society
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• v.38 no.4
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• pp.87-116
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• 2007

The School Library Instruction(SLI) is one of the tool subjects for information literacy. Therefore, the connection with school curricula Is the activation strategy of SLI. The school library Integrated curriculum is Integrating a thinking strategy of SLI and subjects of subject education curricula. The purpose of the school library Integrated curriculum is to strengthen the educational role of teacher-librarian and self-directed learning. In this study, a presented example of the school library Integrated curriculum for the 10th students is based on the cross-curriculum subjects as a strategy of connection and integration.

• Journal of the Korean Society of School Health
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• v.28 no.2
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• pp.67-78
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• 2015

The purpose of the study was to present a model of WHO Health Promoting School easily applicable to small-sized schools in rural areas. Methods: The study analyzed data of 11 small-sized schools in rural areas selected from 85 health promoting schools, an initiative led by the Ministry of Education from 2012 to 2014. Results: Through the analysis, the study found out the operation process of health promoting schools consists of five stages: system development, needs survey & survey on current status, school health policy development, program development & execution, and evaluation. In addition, the study was able to discover three key factors in operating health promoting schools: connection with curriculum, connection with community, and consensus among members. While it turned out the schools were following operation manuals faithfully, the biggest problem with operation was that the stages of needs survey, priority setting, and core task development were not closely coordinated. Conclusion: Although the model suggested in the study fails to reflect the characteristics of small-sized schools in rural areas, it is close to a universal model which could serve as a guideline when regular schools adopt the system of health promoting schools.

• Structural Engineering and Mechanics
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• v.20 no.6
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• pp.695-712
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• 2005

Hybrid coupled shear walls in tall buildings are known as efficient structural systems to provide lateral resistance to wind and seismic loads. Multiple hybrid coupled shear walls throughout a tall building should be joined to provide additional coupling action to resist overturning moments caused by the lateral loading. This can be done using a coupling beam which connects two shear walls. In this study, experimental studies on the hybrid coupled shear wall were carried out. The main test variables were the ratios of coupling beam strength to connection strength. Finally, this paper provides background for rational design guidelines that include a design model to behave efficiently hybrid coupled shear walls.