• Macromolecular Research
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• v.12 no.5
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• pp.528-533
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• 2004

We have prepared amide dendrons having alkyl peripheral units and various focal moieties through a convergent synthetic approach. The amphiphilic properties, due to hydrophilic amide branches and the hydrophobic peripheral units, provide an opportunity for the amide dendrons to self-organize in water. The dendritic architecture itself is also one of the critical factors in the self-organization of the amide dendrons in water. In particular, function-alization was performed at the focal point to elucidate the relationship between the focal functionality and the self-organized structures of the dendritic building blocks in the aqueous phase. The dendron having a short poly(ethylene glycol) monomethyl ether (MeO-PEG) unit (M$\_$n/ =750) as the focal moiety formed a vesicular organization in water. As the size of the hydrophilic focal MeO-PEG increased to M$\_$n/ =2,000 and 5,000, the self-organized structures became rod-type and spherical micelles, respectively. Our observation of multiple morphologies for amide dendrons is in good agreement with previous reports that indicated that the micellar structures changed from vesicles to rod-types and then to spheres upon increasing the size of the hydrophilic moiety of the amphiphiles.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.679-687
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• 2020

This study quantitatively analyzed the effects of self-efficacy in the workplace on job-stress and work-life balance (WLB) using a structural equation model (SEM) to seek ways to increase the WLB. Because the current government promotes the 52-hour weekly policy, WLB that refers to the balance between work and life that is used throughout society. In addition, self-efficacy, which was used mainly in the home and education system, has expanded its scope of application, and efforts to increase it in the workplace are working as demand for the times. The observation variables to be included in the SEM were collected from a questionnaire of 5,454 adults, and AMOS 21 was used for statistical analysis. As a result of the analysis, self-efficacy in the workplace has a negative correlation with stress, and a higher self-efficacy means a higher WLB. The results of this study did not show that the more workers are passionate about their work in the workplace due to work-oriented thinking and behavior rather than home had a lower WLB. In addition, these results can be used to analyze the WLB policy in the ROK Army.

• Journal of Korean Academy of Nursing Administration
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• v.12 no.1
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• pp.140-150
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• 2006

Purpose: The purpose of this study was to determine learning styles and preferred learning methods of clinical nurses. Method: Data were collected from 735 nurses at one university hospital in Seoul. Learning style inventory, a self-report questionnaire was completed by the subjects. Result: Learning styles of nurses were accommodator 35.9%, diverger 30.4%, converger 18.2%, assimilator 15.5%. Learning styles varied significantly with clinical practice area and academic background. Furthermore, RO(reflective observation) learning mode varied significantly according to the clinical practice area. AC(abstractive conceptualization) learning mode varied significantly with job position. AC and AE(active experimentation) learning modes varied significantly according to the academic background and preferred learning method. Preferred learning methods were lecture 24.8%, clinical practice 23.1%, self-directed learning 21.5%, audiovisual education 16.7%, and group discussion 13.9%. Preferred learning methods varied significantly with learning styles and career. Lecture was preferred in diverger and self-directed learning was preferred in assimilator. Clinical practice was preferred in accommodator and converger. Conclusions: This study suggested that clinical education should be applied to nurses after examining learning styles and preferred learning methods. In conclusion, to identify the nurses' learning styles could be helpful for developing the effective educational skill.

• Journal of Educational Research in Mathematics
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• v.10 no.2
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• pp.229-246
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• 2000

The purpose of this paper is to compare and analyze the two different teaching methods of elementary mathematics in the traditional method and in the constructive view. To do so, the actual class in the constructive view has been made for about four months using a class of 45 students in the second grade of an elementary school. After the class was finished, we collected diverse data from the class, such as the responses from the children(self-evaluation, mathematics diary, observation by the investigator, daily report), class evaluation report by other teacher and so on. The results of this research are as follows: First, the traditional class reaches at the goal of learning in a unit time because the class is guided by the teacher but the class in the constructive view is a little flexible because it is contextual. Second, in the constructive process of mathematical knowledge we knew that small group activities or discussion without intervention of teacher was often ended in exhaustive argument without arriving at valid social consensus. Third, the attitude in mathematics was changed from the passive one to the self-regulated ones. Fourth, the class in the constructive view could extend not only the ability of mathematical communication but also the ability of self-directed learning of children. Fifth, it was a considerable change the role of teacher, that is, guide of instruction instead of unique specialist in the classroom. Sixth, finally, the evaluation was made after finishing a unit class in the traditional instruction but it was integrated in a class in a constructive view.

• Smart Structures and Systems
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• v.4 no.3
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• pp.305-318
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• 2008

The development of a digital signal processor based prototype is described in relation to continuing efforts for realizing a fully self-contained active sensor system utilizing impedance-based structural health monitoring. The impedance method utilizes a piezoelectric material bonded to the structure under observation to act as both an actuator and sensor. By monitoring the electrical impedance of the piezoelectric material, insights into the health of the structured can be inferred. The active sensing system detailed in this paper interrogates a structure utilizing a self-sensing actuator and a low cost impedance method. Here, all the data processing, storage, and analysis is performed at the sensor location. A wireless transmitter is used to communicate the current status of the structure. With this new low cost, field deployable impedance analyzer, reliance on traditional expensive, bulky, and power consuming impedance analyzers is no longer necessary. A complete power analysis of the prototype is performed to determine the validity of power harvesting being utilized for self-containment of the hardware. Experimental validation of the prototype on a representative structure is also performed and compared to traditional methods of damage detection.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.350-350
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• 2006

We investigated, via atomic force microscopy and transmission electron microscopy, the effect of shear force on the interfacial morphology of a reactive bilayer polymer system composed of PS-mCOOH and PMMAGMA. It has been observed that in the absence of oscillatory shearing the roughness of the interface increased with reaction period, while at large values of ${\gamma}_{0}\;and\;{\omega}$ it became less than that observed in the absence of oscillatory shearing. This observation may be attributable to the possibility that oscillatory shearing might have hindered the diffusion of polymer chains, which are located away from the interface, to the interface of the layers. However, the effect of ${\gamma}_{0}\;and\;{\omega}$ on the roughness of the interface of (PS-mCOOH)/(PMMA-GMA) bilayer is found to be quite different.

• Journal of Korean Elementary Science Education
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• v.20 no.2
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• pp.197-215
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• 2001

The science in elementary school has the purposes of having interest and curiosity in nature phenomena and things, of understanding basic concepts of science, realizing experimental know-how for students. And it also intends students to develop self-leading research ability and creative problem-solving ability through looking-in and experience about nature. However, existing science is accepted very hard and no interesting, just bothering to prepare more then a ability-developing or interest. In this report, I will analyze the study problems suggested in science textbook from 3rd to 6th grade, then find a new way for study problem suggesting and adopt it. It would help students have interest, approach problem without tense, understand problem exactly, and stand a concreat study schedule of experiment, observation, rearrangement, result interpretation that have students study by themselves. Because the suggesting way of science study problem statement is important thing to develop students' creativity and problem- solving abillity and to make self-leading attitude, I wish the exiting, veneficial, and waiting-for science class, through apply the newly developed methology suggested in this report.

• Journal of Sensor Science and Technology
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• v.18 no.5
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• pp.337-342
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• 2009

This paper describes a robust mobile u-healthcare system with multiple physiological signs measurement capability in real time with integration of WSN(wireless sensor network) technology and CDMA(code division multiple access) network. A cellular phone receives health data in WSN and performs local physiological signs analysis at a phone processor, and then transmits abnormal data to server for further detail or precise health signal evaluation by a medical doctor over a CDMA network. Physiological signs of the patients are continuously monitored, processed and analyzed locally at cellular phone process to produce useful medical information for diagnosis and tracking purposes. By local simple analysis in cellular phone processor we can save the data transmission cost in CDMA network. By using the developed integrate ubiquitous healthcare service architecture, patients can realize self-health checking so that the prevention actions can be taken earlier. Appropriate self-monitoring and self-management can cure disease and relieve pain especially for patients who suffer from chronic diseases that need long term observation.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.390-399
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• 1991

The purpose of this study is to examine the relationship between pesticide use and mortality, and cancer mortality which are recognized as health hazards of pesticides. Data were analyzed from a cohort of 6,066 people aged fifty-five or over and who have been residing in the main island of Kangwha county. Death certificates, computerized citizenship registers searches, and household interview survey lead to get more than ninety-seven percents follow-up rate for the first five year observation period. Important findings are as follows : 1. Age specific mortality rates of pesticide users are significantly lower than those of pesticides nonusers. The SMR of male is 0.80, and 0.58 for females respectively probably due to healthy worker effects. But, age specific cancer mortality rates are significantly higher than those of pesticide nonusers (SMR=1.59) in males. This finding is not observed in females (SMR=0.85), however. 2. Logistic regression analyses showed that self-reported health status, drinking, and smoking histories in male are significantly associated with total mortality rate. The histories of pesticide use are also calculated to be highly associated with cancer mortality as in univariate analyses in males. In female, self-reported health status, age of first delivery are found to be significantly related to total mortality rate. Only drinking history is calculated to be associated with cancer mortalities in females. Data from further observation of 'Kangwha cohort' and indepth analyses of these are highly expected.

• Hwankyungkyoyuk
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• v.20 no.1
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• pp.19-27
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• 2007

This study was intended to answer the question, 'What kinds of effects will be aroused by experiential learning for environment based on living area?'. Experiential learning for environment was operated to 17 elementary school students in 4th grade in Kyeong-san city. The results were drawn analyzing the mind map for the changes of environmental consciousness before and after learning, and they are as below. First, it had an effect to change the meaning association of the relationship between 'river and me'. Meaning association was 'river-a thing' before experiential learning, but it was developed as 'river-a thing-me' after learning. This means that students expanded understanding of the world that they were belonging and self-spatialization was promoted. The expansion of meaning association would be a start point and a method to promote their segmentation for each student. Second, students could self-directly modify misconception and preconception after experiential learning. It showed that students could find meanings in the world that they were belonging by experiential learning for environment, and misconception obtained by concept learning without actual situation could be revised through the truth recognition in meanings, and student could see what things displayed. Therefore preconception would be corrected. Of course, everything would not be completed by just one time of experiential learning, and consistent experience learning should be operated. Third, experiential learning promoted the change of sensitivity. Students had shallow sensitivity, which appeared in the relation with things, since having learned only inside of class without a direct observation. However their sensitivity could be increased by experiencing specific things. Fourth, there was the change of classification recognition. Students found properties of things with a direct observation. It raised their ability to classify things, and to understand an individual thing in 'a class'.