• East Asian mathematical journal
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• 제26권2호
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• pp.115-140
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• 2010

The purpose of this paper was to develop manipulative materials to teach the angle concepts and construct a teaching-learning program by using that. Furthermore, this study analyzed how does the program affect students understanding of the angle concepts. To check the effects of learning activities with manipulative materials on the understanding of an angle concepts, applied observation during class and write a mathematics journal writing, a description of students impressions at the end of the class and analyzed before and after test paper. We find that students approached the subject more friendly and knew well about the mathematical concepts by using materials. Furthermore, this activity helped that way to solve add and subtract of the angle, estimate ability, round angle concept, positive response in mathematics learning.

• Journal of Microbiology
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• 제34권4호
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• pp.384-386
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• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Archives of Reconstructive Microsurgery
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• 제3권1호
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• pp.16-23
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• 1994

A segmental resection and rotationplasty was performed in 23 patients with malignant and aggressive boning tumor of the distal femur or proximal tibia between February 1988 and September 1992 at the Severance Hospital. There were 13 male and 10 female patients. The yongest was 5 years old and the oldest was 37 years old. Mean age at operation was 22 years. Of the 23 cases 14 were osteosarcoma, 7 were giant cell tumor and 2 were synovial sarcoma. After an average observation period of 32.5months, there was no evidence of local recurrence but 6 distant metastasis developed. According to Shriner's rating scale, the functional result were excellent or good in all cases. All patient were convinced that they chosen the appropriate operative procedure and the ability to achieve high level of activity was considered as the main benefit.

• 한국항공운항학회지
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• 제7권1호
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• pp.31-39
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• 1999

Through the use of well-designed measures of ability and aptitude, good selection can reduce training wastage, reduce the risk of accidents and increase the operational effectiveness of the successful trainees. Many countries in the world, they take various kind of aptitude test. Especially in Sweden, not like the other countries, they attach importance to interview test. As a result, they can reduce training wastage and accidents. In case of ROKAF, they take many kind of aptitude test, but it is not directly effective to the selection system. They take the several aptitude test in civil aviation in Korea, especially they attach importance to personality test. For the validity and accuracy of the aptitude test, until training pilot become professional pilot, we need a comparison analysis for initial aptitude test through the continuous observation. For theses process, we need a department with special person and development of testing system.

• 한국초등과학교육학회지:초등과학교육
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• 제19권2호
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• pp.15-27
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• 2000

The purpose of this study was to survey the thinking of children, preliminary elementary teachers and elementary teachers in relation to the experiment of candle's combustion in a bottle on the water, to develop some supplementary experiments for the correction of the misconception on this experiment and to propose a new teaching method for this subject-matter The results of this study can be summarized as follows. 1. Most of the answers are related to the simple observation as the extinguishing of candlelight and the water rising in the bottle after a candle's combustion. And it is appeared that all the groups are similarly short of the ability of experimental design to verify the cause and effect. 2. from the results of the developed supplementary experiments, it is concluded that the main cause of the water rising is not the combustion of oxygen, but the expansion of volume and the releasing of air in the bottle in the bottle by heat of candle's combustion. 3. Based on the above results, a new direction for the teaching method of this subject is proposed.

• Journal of Plant Biology
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• 제11권1호
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• pp.27-32
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• 1968

In the present experiment as a basic study for establishing a hybrid seed orchard, an observation was made on the survivability of grafts using Pinus rigida as the stock and its hybrids as the sciion, and on the shape and germination of pollen collected from grafted plants. The results are summarized as follows: 1. The hybrid scion of P. rigida.taeda or $P. rigida{\times}(P. rigida.taeda)$ grafted into P. rigida stock showed lower survivability than the homoplastic graftings of P. rigida. 2. Five among the eight eleven-year old scions homoplastically grafted into two-year old stock for the staminate strobile one year after their grafting. 3. There was no difference in the size and germination ability between the pollen collected from homoplastically grafted plant and from the normal one. 4. The pollen collected from the grafted plant is thought to be usable for the control pollination as the germination of such pollen was considerably good.

• 한국정밀공학회지
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• 제24권6호
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• pp.66-71
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• 2007

Development of a locomotive mechanism for the capsule type endoscopes will largely enhance their ability to diagnose disease of digestive organs. As a part of it, there should be provided a detection device of their position in human organs for the purpose of observation and motion control. In this paper, a permanent magnet outside human body was employed to project magnetic field on a capsule type endoscope, while its position dependent flux density was measured by three hall-effect sensors which were orthogonally installed inside the capsule. In order to detect the 2-D position data of the capsule with three hall-effect sensors including the roll, pitch and yaw angle, the permanent magnet was extra translated during the measurement. In this way, the 2-D coordinates and three rotation angles of a capsule endoscope on the same motion plane with the permanent magnet could be detected. The working principle and performance test results of the capsule position detection device were introduced in this paper showing that they could be also applied to 6-DOF position detection.

• Journal of Microbiology
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• 제42권2호
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• pp.160-162
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• 2004

Rhodococcus sp. strain T104 is able to utilize both limonene and biphenyl as growth substrates. Fur-thermore, T104 possesses separate pathways for the degradation of limonene and biphenyl. Previously, we found that a gene(s) involved in limonene degradation was also related to indigo-producing ability. To further corroborate this observation, we have cloned and sequenced a 8,842-bp genomic DNA region with four open reading frames, including one for indole oxygenase, which converts indole to indigo (a blue pigment). The reverse transcription PCR data demonstrated that the identified indole oxygenase gene is specifically induced by limonene, thereby implicating this gene in the degradation of limonene by T104.

• Applied Microscopy
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• 제46권4호
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• pp.201-205
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• 2016

Functional surfaces in nature have been continuously observed because of their ability to adapt to the environment. To this end, methods such as scanning electron microscopy (SEM) have been widely used, and their wetting functions have been characterized via environmental SEM. We investigated the superhydrophobic hairy leaves of Pelargonium tomentosum, i.e., peppermint-scented geranium. Their surface features and wettability were studied at multiple-scales, i.e., macro-, micro-, and sub-micro scales. The surfaces of the investigated leaves showed superhydrophobicity at the macro-, and micro-scales. The wetting or condensing behavior was studied for molecule-size water vapors, which easily adhered to the hairy surface owing to their significantly lower size in comparison to that of the surface.

• 천문학회보
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• 제43권2호
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• pp.51.1-51.1
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• 2018

Based on the DOAO/eShels observations, we have derived radial velocity curves of the three Algol-type spectroscopic binary systems : Algol, ${\beta}$ Aur, and ${\varepsilon}$ Per. The radial velocity amplitudes of the primary and the secondary (K1 and K2) were consistent within a few % of the values from the previous studies. Mass ratios between the two stars that constitutes each system ranges ~1 to ~10. In addition to the orbital elements derived, we discuss about the spectroscopic ability of the DOAO/eShels instrument.