• Korean Journal of Materials Research
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• v.28 no.9
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• pp.528-533
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• 2018

In recent years, solar cells based on crystalline silicon(c-Si) have accounted for much of the photovoltaic industry. The recent studies have focused on fabricating c-Si solar modules with low cost and improved efficiency. Among many suggested methods, a photovoltaic module with a shingled structure that is connected to a small cut cell in series is a recent strong candidate for low-cost, high efficiency energy harvesting systems. The shingled structure increases the efficiency compared to the module with 6 inch full cells by minimizing optical and electrical losses. In this study, we propoese a new Conductive Paste (CP) to interconnect cells in a shingled module and compare it with the Electrical Conductive Adhesives (ECA) in the conventional module. Since the CP consists of a compound of tin and bismuth, the module is more economical than the module with ECA, which contains silver. Moreover, the melting point of CP is below $150^{\circ}C$, so the cells can be integrated with decreased thermal-mechanical stress. The output of the shingled PV module connected by CP is the same as that of the module with ECA. In addition, electroluminescence (EL) analysis indicates that the introduction of CP does not provoke additional cracks. Furthermore, the CP soldering connects cells without increasing ohmic losses. Thus, this study confirms that interconnection with CP can integrate cells with reduced cost in shingled c-Si PV modules.

• Polymer(Korea)
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• v.39 no.2
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• pp.317-322
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• 2015

Salinity gradient power is a system which sustainably generates electricity for 24 hrs, if the system is constructed at a certain place where both seawater and river water are consistently pumped. Since power is critically determined by the water flux and the salt rejection, a membrane of water-semipermeable aquaporin protein in cell membranes was studied for pressure-retarded osmosis. NaCl was used as a salt, and $NaNO_3$ was used as a candidate to check the ion selectivity. The water flux of biomimetic aquaporin membranes was negligible at a concentration below 2M. Also, there is no remarkable dependence of water flux and ion selectivity on concentrations higher than 3M. Therefore, the biomimetic aquaporin membrane could not be applied into pressure-retarded osmosis; however, if a membrane could overcome the current limitations, the properties shown by natural cells could be accomplished.

• Journal of the Korea Society of Computer and Information
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• v.15 no.4
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• pp.83-90
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• 2010

In wireless sensor networks, the data transmitted from the sensor nodes are susceptible to corruption by errors which caused of noisy channels and other factors. In view of the severe energy constraint in Sensor Networks, it is important to use the error control scheme of the energy efficiently. In this paper, we presented RS (Reed-Solomon) codes in terms of their BER performance and power consumption. RS codes work by adding extra redundancy to the data. The encoded data can be stored or transmitted. It could have errors introduced, when the encoded data is recovered. The added redundancy allows a decoder to detect which parts of the received data is corrupted, and corrects them. The number of errors which are able to be corrected by RS code can determine by added redundancy. The results of experiment validate the performance of proposed method to provide high degree of reliability in low-power communication. We could predict the lifetime of RS codes which transmitted at 32 byte a 1 minutes. RS(15, 13), RS(31, 27), RS(63, 57), RS(127,115), and RS(255,239) can keep the days of 173.7, 169.1, 163.9, 150.7, and 149.7 respectively. The evaluation based on packet reception ratio (PRR) indicates that the RS(255,239) extends a sensor node's communication range by up about 3 miters.

• Journal of Life Science
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• v.23 no.4
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• pp.487-494
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• 2013

An AlaAT knock-out mutant (alaat) of rice (Oryza sativa L.) was isolated from T-DNA tagging lines and the genotypes of its progeny were determined with AlaAT1-specific primers. The alaat phenotypes showed decreased growth and grain yield when compared with control plants. The activity of AlaAT1 in the mutant plants was practically undetectable. The responses of alaat plants to growth under salt stress were compared with those of control plants by measuring chlorophyll fluorescence and the activities and mRNA expression of antioxidant enzymes. All abiotic stresses tested (salt, drought, and chilling) caused a similar decrease in chlorophyll fluorescence in both alaat and wild type plants. The activity of peroxidase (POX), an antioxidant enzyme, decreased following salt treatment of alaat plants, while control plant showed an increased activity. The mRNA levels for cAPX (cytosolic ascorbate peroxidase), POX2, and AlaAT were determined by RT-PCR following salt stress. No AlaAT1 mRNA was detected in alaat plants. The POX2 mRNA showed a slightly increased level in the wild type but was not detected in alaat plants, in agreement with the activity assays. The levels of cAPX mRNA were greatly increased in both the wild type and alaat plants. The salt stress effects on rice plant growth are therefore proposed to reflect a loss of function of AlaAT, which alters the activity and synthesis of antioxidant enzymes (especially peroxidases), rather than a direct effect on photosynthesis.

• Hwankyungkyoyuk
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• v.6 no.1
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• pp.199-209
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• 1994

To investigate the trends in environmental education research of foreign countries, the paper published in the Journal of Environmental Education from 1984 to 1992 were analyzed. Major results of this study are as follows: 1. Total number of the paper analyzed was 178 and the average numbers of paper published per year were similar. 2. Researchers' majors were various. 3. The major targets of the researches in environmental education were school students. 4. Questionnaire was used in many researches and the main area of researches was strategy for environmental education. 5. Major type of research was survey and the main area of researches was strategy for environmental education. 6. The affective domain was highly concerned in environmental education researches.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.330-339
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• 2009

The material properties of Cedar (Cryptomeria japonica) were evaluated according to heat treatment conditions. The special focus was made on the color control of cedar wood by heat treatment. The difference of color between sapwood and heartwood could be reduced by heat treatment at a temperature above $170^{\circ}C$. Long heating time was more effective in reducing the difference. The Equilibrium Moisture Content (EMC) of heat-treated wood was as low as 50 percent. The result obviously indicates that heat-treated wood is more dimensionally stable in the change of moisture condition than the control. The heat-treated wood was also effective in increasing the durability against wood rotting fungi. However, more study is required to develop heat treatment as an environmentally-friendly technology for wood preservation without chemical. The mechanical properties of heat-treated wood showed relatively higher performance than the control in general. Meanwhile the dramatic decrease in impact bending stress due to the loss of ductility may limit uses of heat-treated wood in certain cases. There were no significant changes in microscopic structure which may cause changes in mechanical properties. Further study on the chemical analysis of heat-treated wood is needed to scrutinize the causes of changes of material properties.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.2
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• pp.3-9
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• 2014

With broadcasting telecommunication, rapid change detection, and construction of spatial information, a long reconnaissance, resources detection in dangerous area and natural disasters, which are difficult for manned aerial vehicles to perform, international recognition in UAV merely being used for limited military purposes has been changed and its demand for both civil and military purpose have been increased. However, considering the current situation that availability of UAV varies and its working areas also broaden, the stability of UAV and the problems of privacy protection are more important in integrated operation of UAV. In particular, the application of UAV system is urgent for the area where rapid decision making due to expedite data construction such as disaster, calamity, and the acquisition of spatial information for small area are required. However, since technical stability for UAV system and institutional regulation in regard of spatial information are not examined, and UAV system has not been integrated with aerial photograph, the limitation of UAV system has been presented. Thus, this study is aimed at analyzing domestic and foreign research trend and institutional research trend in terms of integrated UAV operation, and proposing its implications and the availability of integrated UAV operation for future national spatial information data construction.

• Journal of Music and Human Behavior
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• v.10 no.1
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• pp.25-45
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• 2013

The purpose of this study is to explain experiences of non-music majors to changing their majors into music therapy and to provide the preliminary study for deriving a grounded theory. For that, in-depth interviews were performed targeting 5 students who did not major in music in their undergraduate courses selected from the graduate students who are majoring in music therapy at the colleges located in Seoul. Data was analyzed for the study by applying the modified grounded theory. The result of study showed that they selected the course of music therapy career as they were motivated by the realistic demand for future employment, career potentials and other realistic causes. These factors caused them to study the surrounding situations and conduct the detailed research on the possibility of music therapy. These factors were also dependent on the individual characteristics, external elements and music background. These experiences were connected to the self-integration and pursuit of growth by newly setting their relation to the 'Music Child'. In addition, the demand of being the meaningful existence in relationship also affected them to more specify their aspirations in the progress of career selection on a continual basis. This study is meaningful as it provides the actual information on them.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.642-650
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• 2018

Musical is produced by multiple specialists including director, writer, composer, lyricist, choreographer, music director, actors/actresses and so on. For the success of one musical, all the people with different background should demonstrate their creativities. The basic frame of a work is made by writer, composer and lyricist first unless it is a licensed musical. They are called as Creative Team, and also director, choreographer, actors/actresses and staff are called as Production Team. Both teams are collectively called as Creative Staff. Then, the secondary creative staff members may participate in the work depending on the production size, and each team can consist of the members such as music director, stage designer, sound designer and so on. The staff related to music in Creative Team of the musical is developed with the initiation from the music supervisor who decides the musical color and genre of the work, the fragmentation and the specialization. However, composer or music director takes these roles in charge in Korea. This study aims to establish the roles and concept of vocal coach according to the fragmentation of working process and to investigate their roles and needs in the domestic musical industry upon case analysis of musical production processes in overseas. The common things and differences in the roles and the functions between ordinary voice teachers and musical vocal coaches were analyzed and the cases of vocal coach in the Korean musicals were reviewed by the interviews. In addition, creative team system was reviewed in the Korean musicals.

• Journal of Astronomy and Space Sciences
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• v.14 no.1
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• pp.44-58
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• 1997

The BVR CCD photometric observations of W UMa-type eclipsing binary SS Ari were made on ten nights from November 1996 to December 1996. Eight new times of minimum lights were derived. The analysis of times of minima of SS Ari confirms the suggestions of other previous investigators that the orbital period of SS Ari have been suffering from a sinusoidal varition. The amplitude and period for the cyclic period changes were calculated as about $58^{y}$ and $0.^{d}053$, respectively. The period variation has been discussed in terms of two potential mechanisms: 1) the light-time effect due to a hypothetical third body and 2) deformations in the convective envelope of a magnetically active component. In the earlier case, the third body has a mass of $1.3M_{\odot}$, if exist, in the form of a white dwarf or a binary system. It seems that the system velocities from the spectroscopic observations supports this interpretation. Meanwhile in the latter case, the primary component is mainly responsible for the magnetic activity of this system with a theoretical amplitude of $\pm0.^{m}08$. However, we cannot make a conclusion which is reasonable explanation at this point, due to lack of observational data. Moreover, the period variation of SS Ari shows duplication about $14^y$, cyclic period with an amplitude of about $0.^d001$ to the above periodic change. We also cannot make an acceptable conclusion for it at this time.