• Korean Journal of Optics and Photonics
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• v.28 no.5
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• pp.194-202
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• 2017

The purpose of this study is to analyze how optics concepts and activities have changed according to the revision of the national science curriculum. For this purpose, the optics achievement standards presented in the middle-school science curriculum of the 7th curriculum, 2007 revised curriculum, 2009 revised curriculum, and 2015 revised curriculum, and the optics content presented in the textbooks developed for each curriculum, were compared and analyzed. The optics content is classified into four concepts: the process of viewing an object; light and color; reflection and refraction; and the image from a mirror and a lens. The main results are as follows: First, according to the revision of curriculum, some optics concepts have been added or removed. In particular, big changes have appeared in the concepts of "process of viewing the object", "dispersion", "reflection and refraction" and so on. Second, the content for 'image formation by a mirror and a lens' was gradually reduced, according to the revision of curriculum, and the level of activity was also adjusted. Third, attempts to present the content of textbooks in conjunction with the phenomena and tools that students can experience in everyday life have increased gradually. In addition, based on the analysis of the content of curriculum and textbooks, the implications for optics education have been discussed.

• Korean Journal of Optics and Photonics
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• v.32 no.4
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• pp.163-171
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• 2021

Conventional white light-emitting diodes (LEDs) for lighting applications consist of blue LEDs and yellow phosphors, the spectrum of which lacks deep red. To improve the color-rendering characteristics of white LEDs, a red quantum-dot film was applied to the diffuser plate of LED lighting. The mean free paths of the quantum dots and the concentration of the TiO₂ particles in the diffuser plate were adjusted to optimize the optical structure of the lighting. The color-rendering index (CRI) was greater than 90 for most conditions, which demonstrates that adoption of the red quantum-dot film is an effective way for improving the color-rendering properties of conventional white LEDs. The angular dispersion of color coordinates could be removed by utilizing the optical cavity formed between the diffuser plate and the reflector on the bottom of the lighting, where multiple passages of the light through the quantum-dot film reduced the differences in optical path length depending on the viewing angle.

• Food Engineering Progress
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• v.15 no.3
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• pp.250-256
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• 2011

This study was performed to analyze the quality characteristics of Sulgidduk added with different ratio 0, 10 and 15% (w/w) of apple pomace dietary fiber powder (DFP). Increasing DFP from 0% to 15% was decreased in color L* value from 87.9 to 65.9, while a* and b* values were increased from -1.9 to 5.9 and from 5.0 to 20.5, respectively. Scanning Electron Microscopy (SEM; ${\times}500$) showed that air cell size in the Sulgidduk surface increased as the DEP increased. On the other hand, control without DFP had a compact structure without air cell. Enthalpy by DSC showed that control without DFP, 10 and 20% DEP Sulgidduk after 3 days of storage were 4.83, 3.80 and 3.18 J/g at $4^{\circ}C$ and those of $25^{\circ}C$ were 1.14, 0.60 and 0.60 J/g, respectively. DEP had more effective on retarded retrogradation of Sulgidduk at $4^{\circ}C$ than that at $25^{\circ}C$. Hardness of 15% DEP Sulgidduk was around 42% compared to that of control without DFP after 3 days of storage at $4^{\circ}C$. In hedonic test, 15% DEP Sulgidduk showed the highest overall quality score among samples after making and storage 3 days at $4^{\circ}C$.

• The Korean Journal of Archival Studies
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• no.40
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• pp.29-60
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• 2014

The purpose of this study is to trace the formation process of "parallel provenance" concept in the context of Australia's aboriginal community archives development and draw its implications for contemporary rebuilding of domestic "past affairs-related committee archives". Focused on historical development of aboriginal community archives in Australia, this writing divides its development into three periods: colonial archives, post-colonial archives, and contemporary archives and investigates each period's distinct features in managing and building of aboriginal community archives. First of all, for colonial archives, it pays attention to Australia's archival tradition, which focused on current record-keeping and then development of multiple provenance resulted from this tradition. Second, for post-colonial archives, it examines the appearance of aboriginal people as the subject of documentation category and name indexing on them. Finally, for contemporary archives, it analyzes current activities of Australia's academic world of archival science for overcoming "the otherness" of aboriginal people through conceptualization of "parallel provenance". Conclusively, through current meaning of parallel provenance, this study draws implications for democratic contemporary rebuilding of domestic past affairs-related committee archives, in which historical victims become the subject of archives.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.221-226
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• 2019

This study investigated the optimal amount of shell powder (0.1, 0.2, 0.3, and 0.4%) to add to rice noodles containing 20% rice flour and compared their quality characteristics to those of wheat noodles containing a commercial alkaline reagent (added at 0.4%). As the amount of shell powder was increased, the L and b values (Hunter's color) increased. The pH, turbidity, and water absorption also increased as the amount of shell powder was increased. However, when the shell powder content exceeded 0.3%, the hardness, chewiness, springiness, and tension tended to decrease below acceptable levels. This might be because the shell powder inhibited network formation. The textural properties and pH value of rice noodles containing 0.2% shell powder were similar to those of the wheat noodles. This suggests that 0.2% shell powder may be the optimal amount to add to rice noodles when used as the alkaline reagent.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.1-8
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• 2021

The inverted Y-shaped strip detection method based on acetylcholinesterase (AChE) was developed for the rapid detection of organophosphorus and carbamate pesticides. The inactivation of AChE by organophosphorus and carbamate pesticides has been well known. The AChE catalyzes acetylthiocholine into thiocholine having (-) and (+) charges, and the (+) charge results in aggregation of gold nanoparticle (GNP). Malaoxon and carbofuran were used as standard organophosphorus and carbamate for the development of the inverted Y-shaped strip, respectively. In order to optimize the method, various angles of the Y-shaped strip, different types of nitrocellulose membrane, and concentration of AChE were tested as key parameters. The detection limit of the method was 10 ng/mL for both malaoxon and carbofuran pesticides. No cross-reaction was observed to other pesticides such as atrazine, cyanazine, simazine, bifenthrin, boscalid, metalaxyl, and chlorobenzilate. Recoveries from lettuce spiked when known concentrations of malaoxon and carbofuran were found ranging from 96.4 to 100.7% and 81 to 112.7%, respectively. This study suggests that the inverted Y-shaped strip method based on AChE may be a useful tool for the sensitive, specific, rapid detection of organophosphorus and carbamate pesticides in agricultural products.

• Korean Journal of Environment and Ecology
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• v.34 no.6
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• pp.551-557
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• 2020

This study surveyed the ecological characteristics of Ladislabia taczanowskii at Songcheon Stream from March to November 2019. The species inhabited upstream, where the riverbed structure was mostly covered with boulders and cobbles. The water depth was 31-148 cm, and the stream velocity was fast at 0.94±0.23 (0.51-1.39) m/sec. The gender ratio of females to males was 1 : 0.89. The age according to the total length frequency distribution indicated that the group with 38-70 mm below in total length was one year old, the group with 70-100 mm was two years old, the group with 100-120 mm was three years old, and the group over 120-128 mm was over four years old. The total length of sexually mature fishes was 70 mm for females and 75 mm or more for males. The spawning season was from May to August, and the water temperature was 15.5-20.1℃ during the period. The prosperous spawning season was from June to July, and the water temperature was 15.8-17.2℃ during the period. The spawning ground was where the riffle began in the pool, and its bottom was formed of sand and gravel. The width was about 150 cm, and the water depth was 20 to 50 cm. The average number of eggs in the ovaries was 821 (401-1,314) per matured female, and the matured eggs were yellowish and spherical with a mean diameter of 1.62±0.02 (1.43-2.01) mm. The live foods of L. taczanowskii Cyanophyta, Chlorophyta, Bacillariophyta, Ephemeroptera, and Diptera. The feeding habit of L. taczanowskii is omnivorous, but more than 90% of the stomach content was attached algae.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.1-7
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• 2023

This study was performed to understand the reproductive ecology of cephalopods, described the microanatomical structure of the male reproductive organs and spermatophore in the common squid, Todarodes pacificus, a major cephalopods in Korea. The common squid was gonochorism and had sexual dimorphism, the color of the reproductive organs reflected on the mantle and the presence of the hectocotylus. Male reproductive organs were composed of testis, primary vas deferens, spermatophoric gland (seminal vesicle), spermatophoric sac (Needham's sac) and secondary vas deferens. The male has specialized reproductive organs such as the spermatophore forming organ, spermatophoric gland. Testis was histologically a seminiferous tubule type. The primary vas deferens was a thin and inverted triangular spring-like form that connected from the rear of the testis to the spermatophoric gland. Inside, it was filled with sperm of basophilic in H-E stain. The spermatophoric gland is an irregular oval connected to the primary vas deferens and spermatophoric sac, and there were a number of tubular glands. The spermatophoric sac is a tubular structure located between spermatophoric gland and secondary vas deferens, and a number of spermatophores have been identified in the lumen. The secondary vas deferens was connected to the posterior of the spermatophoric sac and had a spermatophore inside. The spermatophore was a long, transparent tube about 22 mm long, with a sperm mass inside.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.55-64
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• 2002

This study was carried out to determine agronomic and genetic characteristics of the production process in tropical yams(Dioscorea alata L.). To make clear the possibility of cultivation of tropical yams in the Suwon area, the growth of the aboveground parts and the enlargement of tuber of Dioscorea alata, were investigated. The aboveground parts of the plants whose sprouted mother tuber were planted in late April were grown slowly until the 70-days after planting and grown rapidly after. From about 50-days after plantation, total length of vines slowly decreased due to the burning of the branch vines of lower modes. With regard to the branching progressed to 4th for the solo yam and to 6th for purple yam. The secondary branches tended to grow better. When the formation of daughter tubers was observed at the 50-days after planting, their enlargement was very slow. The rapid growth of tubers began at the 40-days and continued to the 90-days. General components such as protein, fiber, and lipid were higher in D. opposita rather than in D. alata. Hardness of D. alata was 2696.2 while that of D. opposita was 4946.9. Lightness of D. alata was 73.99, being higher than that of D. opposita.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.50-62
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• 2004

Tuber yield and content of general component and diosgenin which is a main bioactive property were investigated in order to determine the growth characteristics of round typed yam(Dioscorea opposita L.) and the potential of artificial culture at Suwon, Korea. Tubers of round yam was initiated to form at 60 days after planting and then enlargement of tubers lasted by 160 days after planting. Compared to short typed yam(108g), tuber weight of round yam was higher(127g) on the basis of dry weight at 200 days after planting. In comparison of general component between round yam and short yam, protein of round yam(3.62%) was higher than short yam(2.10%). Water content in round yam(64.5%) was lower in short yam(79.4%), indicating a higher dry weight ratio of round yam. Hardness of round yam was 2787.6 while short yam showed about two times higher hardness(4946.9). Lightness was higher in round yam(77.4). In tuber extracts analysis, diosgenin content was respectively 3.32% in round yam and 2.61% in short yam.