• Korean Journal of Microbiology
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• v.36 no.2
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• pp.155-160
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• 2000

Pseudomnas sp. HJ-2 is capable of producing a rubber-elastic polyhydroxyalkanoate (PHA) consisting of 3- hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyheptanoate (3HHp) from heptanoic acid as the sole carbon source. The polyester produced was a blend of poly(3HB-co-3HV) and poly(3HHp). Although the mixing of poly(3HHp) fraction to poly(3HB-co-3HV) resulted in a decrease of modulus, the sole fraction of poly(3HB-co-3HV) with a high molar fraction of 3HV was shown to be an elastomer with the maximum percent strain of 740%. The biomass yield and the PHA synthesis were relatively high when the initial heptanoic acid concentration was 40 mM, and were significantly decreased when the substrate concentration exceeded 50 mM. The accumulation of PHA was stimulated by deficiency of nitrogen and phosphorus in the medium. The PHA contents and its monomeric compositions were greatly affected by pH and oxygen transfer rate. At pH 7.5, poly(3HB-~0.38% 3HV) was produced from heptanoic acid and a mixture of 95% 3HHp and 5% 3HV was produced at pH 8.0. Increased conten1 of 3HHp in the polyesters with lhe increasing oxygen transfer rate by agitation speed a1 a fixed aeration rate was observed.

• Journal of the Korean association of regional geographers
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• v.10 no.4
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• pp.757-774
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• 2004

This paper is to reclassify systematically the functions of urban river: that is, water supply, land management, transportation and energy source as social and economic function; formation of geomorphic surface, water-side landscape, community constitution and boundary and separation between regions as spatial function; and drainage of waste water, purification, habitation, and weather regulation as ecological function. On the basis of this reclassification, it can be argued that the socio-economic functions (eg. water supply) of the river among the functions of the river have been strongly mobilized in the process of modernization, while the spatial function and ecological function of urban river have been ignored. The Kumho river which flows through Daegu and the adjacent area has made a great contribution to the modem development process of the river basin area, but as a result of a selective development of a specific function of the river, that is the social and economic function, it now suffers from the lack of instream flow and is deprived of its original functions with the water pollution and degradation. Moreover the Daegu region seems no longer possible to develop on the dependence of the river. In order to overcome this kind of social and environmental crisis, this paper is to suggest both some principles and main evaluating indicators to restore the original and comprehensive functions of the river, and important measures to make the co-evolution of the city and the river possible.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.248-253
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• 2015

This study applied the portfolio approach as a means to provide decision-making information for the establishment of the optimal production plan for non-timber products. The target items of non-timber forest product were Chestnut, Jujube, Walnut and Astringent Persimmon. The data used in this study were the annual report of forestry production cost survey which contains the annual production, annual gross income, and annual product cost from 2008 to 2013. These data were used to calculate the expected return of non-timber forest product. The objective function in the portfolio models was to minimize the expected return volatility, called risk and the constrain was to achieve the minimum expected return rate. Results indicated that the production ratio of the nuts and fruits in 2013 was 7% for Chestnut, 20% for Jujube, 5% for Walnut and 68% for Astringent Persimmon. Furthermore, portfolio presented that the production ratio was 10% for Chestnut, 9% for Jujube, 3% for Walnut and 78% for Astringent Persimmon in the near future. The cause was analyzed due to maintain stable production and income of Astringent Persimmon and Chestnut. Meanwhile, the revenue of Walnuts and Jujube was in great variation with relatively higher revenues.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.6
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• pp.10-21
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• 2010

In the cluster-tree network which covers wide area network and has many nodes for monitoring purpose traffic is concentrated around the sink. There are long transmit delay and high data loss due to the intensive traffic when IEEE 802.15.4 is adapted to the cluster-tree network. In this paper we propose Dynamic Channel Allocation algorithm which dynamically allocates channels to increase the channel usage and the transmission success rate. To evaluate the performance of DCA, we assumed the monitoring network that consists of a cluster-tree in which sensing data is transmitted to the sink. Analysis uses the traffic data which is generated around the sink. As a result, DCA is superior when much traffic is generated. During the experiment assuming the least amount of traffic, IEEE 802.15.4, has the minimum length of active period and 90% data transmission success rate. However DCA maintains 11.8ms of active period length and results in 98.9% data transmission success rate.

• Journal of The Korean Association For Science Education
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• v.33 no.5
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• pp.1021-1040
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• 2013

In order to explore the influences of coteaching through mentoring upon the teaching professionalism of beginning science-gifted education teachers, this case study deeply investigated the change processes in the aspects of pedagogical content knowledge (PCK). Two beginning teachers planned, performed and reflected together their science instructions for science-gifted students in secondary school during four 3-hour classes. Since the second instruction, pre-, during-, and post-mentoring were conducted, we collected various data related to teachers' planning processes, videotaped all coteaching science classes, and wrote field notes. We also recorded in-depth interviews with the teachers and the whole process of mentoring. All the data were analyzed by using the constant comparative method. The results of the analyses indicated that coteaching through mentoring positively changed the teachers' PCK. Above all, we found that coteaching and mentoring strategies generated a significant synergy effect through a mutually complementary relationship. The teachers developed deep practical knowledge about the enrichment curriculum, which placed more emphasis on developing cognitive and/or affective characteristics of science-gifted students. The teachers also improved their knowledge about the characteristics of science-gifted students and the instructional strategies appropriate for developing them. Moreover, practical knowledge about assessment domains and methods used in science-gifted education were improved. Knowledge on science content necessary for effective inquiry instruction was also improved.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.171-178
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• 2020

Amid public's growing interest on garden and more leisure time of modern life-style, there is an effort by the government to utilize forest as public garden. In order to utilize forests as pubic garden, a new concept of "Forest Garden" should be defined and introduced first. Furthermore, introducing a new concept requires academically analyzing values of a new concept before a new concept is widely used. Thus, we aimed to clarify the concept of forest garden by conducting Delphi technique research and factor-analysis of survey results. More specifically, delphi technique research was conducted to extract composition elements and explanation elements of forest garden. Factor analysis was conducted on the top 25 elements and 5 values were extracted as a result. They are form, scenery, ecology, history/cuture and usefulness which are essential values required of forest garden. Forest garden should have all of 5 values and be capable of function as both forest and garden which would also need continuous maintenance. We believe this study is the first one to establish definition of forest garden and more specific and realistic definitions need to be built through continuous research, 000 experiment and on-site evaluation. We also believe that this study will serve as foundation for further efforts in building forest garden in various space and in defining proper concept of forest garden.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.3
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• pp.37-43
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• 2011

Reliability of piping systems is essential to the safety of any important industrial facilities. During an earthquake, damage to the piping system can occur. It can also cause considerable economic losses and the loss of life following earthquakes. Traditionally, the study of the secondary system was less important than primary structure system, however it has recently been emerging as a key issue for the effective maintenance of the structural system and to help reduce nonstructural earthquake damage. The primary objectives of this study are to evaluate seismic design requirements and the seismic performance of gas and fire protection piping systems installed in reinforced concrete (RC) buildings. In order to characterize the seismic behavior of the existing piping system in an official building, 10 simulated earthquakes and 9 recorded real earthquakes were applied to ground level and the building system by the newmark average acceleration time history method. The results developed by this research can be used for the improvement of new seismic code/regulatory guidelines of secondary systems as well as the improvement of seismic retrofitting or the strengthening of the current piping system.

• Child Health Nursing Research
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• v.21 no.1
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• pp.11-19
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• 2015

Purpose: The purposes of this study were to develop an infant sleep health education program using a video for SIDS prevention education and to measure the effects of the program. Methods: The infant sleep health education program consisted of presentations and motor images. The formation of educational material was directed by the systematic design of instruction. Participants in this study were 59 primiparous women from postpartum care centers. The instruments used in this study were criterion referenced test items for knowledge about infant sleep health and confidence inventory. Experimental group I was given the treatment of infant sleep health education program. Experimental group II was given the program using a video reinforcement after 2 weeks. On the other hand, control group was given no treatment. Results: There was a significant increase in knowledge and confidence in the performance of mother's roles of both experimental group I and experimental group II over the control group. No significant difference was founds for knowledge and confidence in the performance of mother's roles between experimental group I and II. Conclusion: The results indicate that this program is a very effective intervention for better sleep health in infants by helping the mothers increase confidence in their role performance.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.91-94
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• 1997

This experiment was carried out to investigate the effects of black P.E. film mulching by different sowing dates on the growth and yield of Achyranthes japonia NAKAI. Emergence rate and the growth increment were increased in black polyethylene (P.E.) film mulching of sowing date at April 1. Dried root yield was highest by 3,190kg/ha in black P.E. film mulching and earlist sowing at April 1 with 20% increase compared to that of non mulching at April 1 planting.

• Journal of the Korean Geotechnical Society
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• v.34 no.8
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• pp.5-14
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• 2018

The grain size of clastic sedimentary rocks classifies the rock types and also causes of anisotropy of the rock. The anisotropy is one of the most important factors that dominates the strength and weathering behavior of rocks. The anisotropy of clastic sedimentary and igneous rocks in the Gyeongsang Basin including Yeongju, Daegu, and Busan were analyzed by magnetic susceptibility expressed by the degree of anisotropy and shape parameter. As the results of the study, the sandstone deposited under lacustrine environment unaffected by the external force shows 1.03 degree of anisotropy. The degrees of anisotropy of the rocks affected by faults and fault rocks show 1.06 and 1.14, respectively. The magnetic susceptibility of rocks is to decrease with the distance from the fault. A fresh mudstone and shale formed by fines show a similar magnitude of the degree of anisotropy to fault rock and correspond to oblate shape parameter due to their sedimentary structure. Due to these reasons, we need attention in design, construction, and maintenance of a structure constructed in mudstone and shale.