• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.6
• /
• pp.743-748
• /
• 2019

This study suggested a process of redesigning and implementing problem based learning to enhance students' active and collaborative learning activities and learning outcomes. The results of this study are as follows. First, the ef ect of class participation, academic self-regulated learning, and academic self-efficacy were examined. As a result, first, the average of learning activity, class extension, and participation in class was high in the difference between before and after class. Second, the post average scores of all the factors except the 'evaluation' were higher than before. Third, academic self-efficacy showed a significant difference only in 'task preference'. Finally, students' satisfaction with the class was also high. The professor was also able to grasp the characteristics of individual students by designing and operating the classes using PBL, and it was confirmed that the interaction with students increased. Based on the results of this study, we discussed the limitations and educational implications of the problem based learning class and propose successful problem based learning design and operation of the classroom.

• 한국노년학
• /
• v.28 no.4
• /
• pp.1265-1278
• /
• 2008

The purpose of this study was to study the Relationships between Sport for All Participation and Physical and Mental Function affecting the Elderly's Self-perceived Health. For accomplishing this purpose of this study, the 308 subjects were selected by the multi-stage stratified cluster sampling method from the Seoul, in the years of 2008. presently. Out of the 360 questionnaires responded to, only 308 were used for data analysis because 52 were responded to incompletely or incorrectly. The survey questionaries were used to collect data. The questionary for physical function state were developed and standardized by kung-hee chung(1993), yang-lae Kim(2005). And mental function state were divided two parts; self-perceived scale and depress scale. The questionary for self-perceived scale were based on MMSE-K(Mini Mental State Examination-Korea). The questionary for Depression were based on Depression Scale developed by Beck(1978), adapted in Korean and standardization by Lee Young-ho & Song Jong-yong(1991), regulated by Jo Gyu-whang(2004). From the analysis of this study, the following conclusions were obtained: First, according to the elderly people's participation in leisure sport activities, it partially affected physical and mental function state. Second, according to the degree of elderly people's participation in leisure sport activities, it partially affected physical and mental function state.

• Human Ecology Research
• /
• v.52 no.1
• /
• pp.43-53
• /
• 2014

The purpose of this study was to 1) investigate the characteristics of burnout of Korean elementary school students and 2) develop and validate the Korean Academic Burnout Scale-Elementary School Students (KABS-ESS). Fifty-one behavioral descriptions of burnout extracted through a preliminary survey, focus group interview, and literature review were administered to a sample of 531 elementary students of the 4th to 6th grade in Gyeonggi Province. The results of an exploratory factor analysis indicated that the structure of the burnout of Korean elementary school students consists of seven factors (i.e., inefficacy, avoidance, cynicism, emotional exhaustion, physical exhaustion, antipathy and cognitive exhaustion), and this structure of final 28 items was confirmed by the confirmatory factor analysis. The KABS-ESS showed a correlation of .771 with a representative academic burnout scale, Maslach Burnout Inventory-Student Survey, and -.561 with the academic engagement scale, indicating that both convergent and discriminant validities were confirmed. Furthermore, all fit indices of the structural equation model of the Schaufeli and Bakker's job demands-resources in an academic setting were satisfactory, and the possibility of the validity generalization of the model was supported. The demand variables predicting academic burnout and engagement were academic overload and parental pressure, while self-resilience, self-regulated learning strategies, and parental and the teacher's support were identified as the resource variables. Lastly, the implications and future direction of the present study were discussed.

• Journal of Korean Medical classics
• /
• v.21 no.2
• /
• pp.151-172
• /
• 2008

This study searched fundamental basis of four-constitution medicine from the principle of "Yeokgyeong(易經)" that is scientific foundations of Dongmu(東武) Ijema(李濟馬)'s four-constitution medicine based on system of "Yeokgyeong(易經)" and looked into the principle of our-constitution medicine ontologically. That is to say, the translation of five phase(五行) that represented in "Hwangjenaegyeong(黃帝內經)" regulated that substance of five phase is spleen-earth(脾土). But four-constitution medicine mentions the substance as heart-earth(心土) in place of spleen-earth. Because of it's standpoint, the differences on meanings between spleen-earth and heart-earth on the substance of five-phase becomes motive to interpret scientific system of four-constitution medicine fundamental wrongly. For that reason, the research of this title is needed. The results was summarized as follows. First, in ontological view point of structure of four-constitution, five phase is substance and phenomenon, in other words it includes earth of unrevealed substance and wood, fire, metal and water of self-manifestation of existence. Second, in axiological view point, the four-constitution represent principles and contents of four virtues of human nature. And so the innate four virtues ontologically based on four-constitution of heaven. Therefore a human being is endowed innately benevolence, courtesy, justice, intelligence of four virtues. Third, the concept of greater and lesser of Eum(陰, yin) and Yang(陽, yang) in Dongmu(東武)'s four-constitution medicine is four-constitution in "Yeokgyeong(易經)". Greater principle(太極) and four-constitution is a relation of substance and phenomenon. Fourth, the origin and structure of four-constitution medicine includes the structure and principle of natural philosophical Eumyang and four-constitution, the human-centric theory and sciences of human nature and natural laws and medical experience of traditional oriental medicine and medical principle.

• Journal of Power Electronics
• /
• v.6 no.1
• /
• pp.52-66
• /
• 2006

This paper proposes a wind energy conversion system connected to a grid using a self-excited induction generator (SEIG) based on the maximum power point tracking (MPPT) control scheme. The induction generator (IG) is controlled by the MPPT below the base speed and the maximum energy can be captured from the wind turbine. Therefore, the stator currents of the IG are optimally controlled using the indirect field orientation control (IFOC) according to the generator speed in order to maximize the generated power from the wind turbine. The SEIG feeds a (CRPWM) converter which regulates the DC-link voltage at a constant value where the speed of the IG is varied. Based on the IG d-q axes dynamic model in the synchronous reference frame at field orientation, high-performance synchronous current controllers with satisfactory performance are designed and analyzed. Utilizing these current controllers and IFOC, a fast dynamic response and low current harmonic distortion are attained. The regulated DC-link voltage feeds a grid connected CRPWM inverter. By using the virtual flux orientation control and the synchronous frame current regulators for the grid connected CRPWM inverter, a fast current response, low harmonic distortion and unity power factor are achieved. The complete system has been simulated with different wind velocities. The simulation results are presented to illustrate the effectiveness of the proposed MPPT control scheme for a wind energy system. In the simulation results, the d-q axes current controllers and DC-link voltage controller give prominent dynamic response in command tracking and load regulation characteristics.

• Journal of IKEEE
• /
• v.21 no.1
• /
• pp.66-69
• /
• 2017

In recent year, energy harvesting technologies from the ambient environments such as light, motion, wireless waves, and temperature again a lot of attraction form research community [1-5] due to its efficient solution in order to substitute for conventional power delivery methods, especially in wearable together with on-body applications. The drawbacks of battery-powered characteristic used in commodity applications lead to self-powered, long-lifetime circuit design. Thermoelectric generator, a solid-state sensor, is useful compared to the harvesting devices in order to enable self-sustained low-power applications. TEG based on the Seebeck effect is utilized to transfer thermal energy which is available with a temperature gradient into useful electrical energy. Depending on the temperature difference between two sides, amount of output power will be proportionally delivered. In this work, we illustrated a low-input voltage energy harvesting circuit applied discontinuous conduction mode (DCM) method for getting an adequate amount of energy from thermoelectric generator (TEG) for a specific wearable application. With a small temperature gradient harvested from human skin, the input voltage from the transducer is as low as 60mV, the proposed circuit, fabricated in a $0.6{\mu}m$ CMOS process, is capable of generating a regulated output voltage of 4.2V with an output power reaching to $40{\mu}W$. The proposed circuit is useful for powering energy to battery-less systems, such as wearable application devices.

• Clinical and Experimental Reproductive Medicine
• /
• v.7 no.1_2
• /
• pp.3-10
• /
• 1980

Pituitary gonadotropes, as target cells, exhibit cyclic changes in terms of LH and FSH release in synchrony with the estradiol levels. The ultimate release is determined by the relative size of the two pools of gonadotropins, which is regulated by the two controllers: LH-RH and estradiol. LH-RH appears to serve as a primary drive on the gonadotrope, stimulating gonadotropin synthesis, storage, and release. Estradiol amplifies the action of LH-RH and induces the development of a self-priming effect of LH-RH except that it impedes LH-RH mediated gonadotropin release. Negative and positive feedback action of estradiol is revealed to operate by different mechanisms. The pituitary capacity increases severalfold from early to late follicular phase, which is considered to be prerequisite for the development of mid-cycle surge. CNS-hypothalamic dopamine, norepinephrine, and prostaglandins, as well as LH-RH, are involved in the negative and positive feedback effects of estradiol. The possible mechanisms in the triggering of LH-RH release for the initiation of midcycle LH-RH surge are considered.

• Biomolecules & Therapeutics
• /
• v.29 no.4
• /
• pp.384-391
• /
• 2021

Currently, the expanding recreational use of synthetic cannabinoids (SCBs) threatens public health. SCBs produce psychoactive effects similar to those of tetrahydrocannabinol, the main component of cannabis, and additionally induce unexpected pharmacological side effects. SCBs are falsely advertised as legal and safe, but in reality, SCB abuse has been reported to cause acute intoxication and addictive disorders. However, because of the lack of scientific evidence to elucidate their dangerous pharmacological effects, SCBs are weakly regulated and continue to circulate in illegal drug markets. In the present study, the intravenous self-administration (IVSA) paradigm was used to evaluate the abuse potential of three SCBs (AM-1248, CB-13, and PB-22) in rats. All three SCBs maintained IVSA with a large number of infusions and active lever presses, demonstrating their reinforcing effects. The increase of active lever presses was particularly significant during the early IVSA sessions, indicating the reinforcement-enhancing effects of the SCBs (AM-1248 and CB-13). The number of inactive lever presses was significantly higher in the SCB groups (AM-1248 and CB-13) than that in the vehicle group, indicating their impulsive effects. In summary, these results demonstrated that SCBs have distinct pharmacological properties and abuse potential.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.1
• /
• pp.65-70
• /
• 2022

BACKGROUND: The Geomunoreum Lava Tube System (GLTS) is both vast and culturally valuable. The Jeju Volcanic Island and Lava Tubes, which are partly composed of the GLTS, have been declared as a United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage Site. Exploration of the caves is strictly regulated to conserve these vulnerable environments. Photographs provide limited information and do not describe the entire environment comprehensively. Therefore, we created several illustrations of the lava tubes to display their environmental features. METHODS AND RESULTS: We explored six lava caves (upstream and downstream) in the GLTS and photographed their geological features and yellow walls, the colors of which are influenced by microbial mats. We compared the hex codes of the wall colors using the Clip Studio v1.10.5 software and created illustrations that accurately represent the scale and features of the caves. CONCLUSION(S): Upstream and downstream caves of the GLTS differ in scale and volcanic features. We illustrated various characteristics of the caves including lava cave features, vegetation, and microbial mats. We also described the internal and external cave environments.

• Journal of The Korean Association For Science Education
• /
• v.29 no.2
• /
• pp.137-155
• /
• 2009

The purpose of the present study was to analyse the effectiveness of a gifted education program. To analyse the effectiveness of an education program for the gifted affiliated with a university, the study carried out a quasi-experimental design to compare the 153 gifted students who enrolled in an education center for the gifted and the 131 potentially gifted students who were nominated by teachers for their high achievements and interests in science but without any education services for the gifted. These two groups of students were compared in the aspects of problem finding ability in science, motivation, self regulation, science-related attitudes, and science anxiety through the pre- and post-treatment settings. The results indicated that the gifted group showed a significant improvement in originality and elaboration of problem-finding ability, but the potentially gifted group showed significant decrease in most variables of problem finding. Related to motivation and self-regulated learning, gifted students showed an increase in cognitive strategy use and decrease in intrinsic value, but the potentially gifted students showed significant decreases in most variables related to motivation and self-regulation, except intrinsic value. Related to the scientific attitudes and science anxiety, there were no significant changes between pre- and post-tests in the gifted group, but significant decreases in most variables were found in the potentially gifted group. The results of paired t-test and Ancova indicate that significant differences between the gifted and the potentially gifted groups are mainly due to the significantly lowered performance in post tests in the potentially gifted group, rather than a significant increase in gifted group.