• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.43-55
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• 1976

Fertilization and early development of turbo cornutus was studied based on the samples which were collected in Yeosu area. Particular emphasis was paid on induction of artificial spawing, fertilization rate, preembryonic development, the growth of the early larva and larval survival to various salinity. Among the various methods for induction of artificial spawning which have been tested for the present study, drying by exposure to air is the. most efficient, and percentage fertilization rate was $83.8-96.4\%$. The diameter of fertilized eggs was $0.182{\pm}0.0028mm$; and the diameter of egg membrane was $0.245{\pm}0.093mm$. Under the temperature range of $20.6-25.4^{\circ}C$ the larvae hatched out after 11:05-11:15 hours of fertilization. After 3.0-3.5 days of fertilization the planktonic larvae begand to settle, and the settlement terminated within 5 days. During the period of 150 days of early culturing the diameter growth of shell(M) and the diameter of shell aperture(A) was formulated as follows: $$1972\;M=0.33e^{0.02070D}$$ $$A=0.19e^{0.02282D}$$ $$1973\;M=0.32e^{0.02282D}$$ $$A=0.16e^{0.02596D}$$ During the same period of early culturing the relative growth of shell diameter and the diameter of shell aperture was formulated as follows : 1972 A=0.6478 S-0.1575 1973 A=0.5897 S-0.0515 After 11 days of larval hatching $0.02-0.18\%$ of planktonic larvae settled. After 150 days of settlement the survival rate of the early shells was $7.4-21.6\%$. Under the temperature range of $21.0-22.7^{\circ}C$ the optimum salinity range for the development of egg and the planktonic larvae was $30-35\%_{\circ}$.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.45-55
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• 2001

Gametogenes, reproductive cycle, first sexual maturity(biological minimum size), sex ratio and larval development of the marsh clam Corbicula japonica were investigated monthly by histological observations. Samples were collected in brackish water of Gokgang stream, Kyungsangbuk-Do, Korea, from August 1997 to July 1998. Sexuality of Corbicula japonica is dioecious and the species are an oviparous clam. The gonads are irregularly arranged from the sub-region of mid-intestinal gland in visceral cavity to reticular connective tissue of foot. The ovary is composed of a number of ovarian sac which are branched arborescent. Oogonia actively proliferate along the germinal epithelium of ovarian sac, in which young oocytes are growing. The testis is composed of a number of testicular tubules, and the epithelium of the tubule has function of germinal epithelium, along which spermatogonia actively proliferate. A great number of undifferentiated mesenchymal tissue and eosinophilic granular cells are abundantly distributed between developing oocytes and spermatocytes in the early developmental stages. With the further development of the ovary and testis these tissue and cells gradually disappear. Then the undifferentiated mesenchymal tissue and eosinophilic granular cells are considered to be related to the growing of the oocytes and spermatocytes. The spawning period is from July to September, and the main spawning occur between July and August when seawater temperatures reach above 22$^{\circ}C$. The reproductive cycle of this species can be divided into five successive stages; early active (February to April), late active (May to July), ripe (June to September), partially spawned (July to September), degenerative (September to October) and resting stage (October to February). Percentages of first sexual maturity of female and male clams ranging in length from 10 mm to 12 mm are over 50% and 100% for clams over 16.0 mm in shell length. Fertilized eggs or Corbicula japonica were 80-90 ${\mu}{\textrm}{m}$ in diameter. In the early embryonic development of C. japonica, the appearance of polar body, trochophore and D-shaped veliger were observed around 40 min., 27 hours and 4 days after spawning, respectively, at a water temperature of 26.5-28.$0^{\circ}C$. The size of larvae of early umbo stage was about 185-210 ${\mu}{\textrm}{m}$ in shell length, 160-180 ${\mu}{\textrm}{m}$ in shell height around 7 days after fertilization. The correlation of relative growth between the culture day (D) and shell length (SL) was expressed by the following simple formula from D-shaped veliger to metamorphosing stage; SL = 13.300D + 209.36($r^2$= 0.9078).

• The Korean Journal of Malacology
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• v.30 no.1
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• pp.87-93
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• 2014

The Morphological characteristics of four species of Korean Abalone species, Nordotis discus hannai, N. discus discus, N. gigantea, N. madaka were compared. then Phenotypic traits were characterized. we collected from coast of samchonpo, sacjon-si, Gyeongsangnam-do and jeju-do of korea 69 individual of Nordotis discus hannai from 2013 December to 2014 January, 180 individual of N. discus, 72 individual of N. gigantea and 54 individual of N. madaka respectively then morphological traits of theses species characteristics were compared. The relationship between Shell length (SL), shell breth (SB), shell height (SH) and total weigh (TW) was expressed by the following equation: SB = 0.6346SL + 3.9082 ($R^2$ = 0.8956), SH = 0.2399SL + 3.2609 ($R^2$ = 0.8024), $TW=0.0009SL^{2.5622}$ ($R^2$ = 0.8088) in the Haliotis discus hannai, SB = 0.7249SL + 1.8035 ($R^2$ = 0.9634), SH = 0.3115SL - 11.223 ($R^2$ = 0.8593), $TW=0.0001SL^{2.9696}$ ($R^2$ = 0.8956) in the H. discus discus, SB = 0.7730SL - 1.1931 ($R^2$ = 0.933), SH = 0.2082SL + 3.2627 ($R^2$ = 0.6927), $TW=0.0002SL^{2.8330}$ ($R^2$ = 0.8431) in the Haliotis gigantea, SB = 0.7513SL - 1.0951 ($R^2$ = 0.913), SH = 0.2618SL - 6.1538 ($R^2$ = 0.6927), $TW=0.0001SL^{2.9614}$ ($R^2$ = 0.9353) in the Haliotis madaka.

• Journal of Gifted/Talented Education
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• v.22 no.3
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• pp.619-637
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• 2012

The purpose of this study is to develop a new program for elementary math-gifted students by using 'Girih Tililng' and apply it to the elementary students to improve their math-ability. Girih Tililng is well known for 'the secrets of mathematics hidden in Mosque decoration' with lots of recent attention from the world. The process of this study is as follows; (1) Reference research has been done for various tiling theories and the theories have been utilized for making this study applicable. (2) The characteristic features of Mosque tiles and their basic structures have been analyzed. After logical examination of the patterns, their mathematic attributes have been found out. (3) After development of Girih tiling program, the program has been applied to math-gifted students and the program has been modified and complemented. This program which has been developed for math-gifted students is called 'Exploring the Secrets of Girih Hidden in Mosque Patterns'. The program was based on the Renzulli's three-part in-depth learning. The first part of the in-depth learning activity, as a research stage, is designed to examine Islamic patterns in various ways and get the gifted students to understand and have them motivated to learn the concept of the tiling, understanding the characteristics of Islamic patterns, investigating Islamic design, and experiencing the Girih tiles. The second part of the in-depth learning activity, as a discovery stage, is focused on investigating the mathematical features of the Girih tile, comparing Girih tiled patterns with non-Girih tiled ones, investigating the mathematical characteristics of the five Girih tiles, and filling out the blank of Islamic patterns. The third part of the in-depth learning activity, as an inquiry or a creative stage, is planned to show the students' mathematical creativity by thinking over different types of Girih tiling, making the students' own tile patterns, presenting artifacts and reflecting over production process. This program was applied to 6 students who were enrolled in an unified(math and science) gifted class of D elementary school in Daejeon. After analyzing the results produced by its application, the program was modified and complemented repeatedly. It is expected that this program and its materials used in this study will guide a direction of how to develop methodical materials for math-gifted education in elementary schools. This program is originally developed for gifted education in elementary schools, but for further study, it is hoped that this study and the program will be also utilized in the field of math-gifted or unified gifted education in secondary schools in connection with 'Penrose Tiling' or material of 'quasi-crystal'.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.445-455
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• 2007

This study surveyed university students in the Seoul area regarding their awareness of family restaurants and visiting experiences. Frequency analysis was used to study the data. Most of the repliers (92.0%) had visiting experiences and visited on weekends (72.4%), paying \$10,000{\sim}15,000$ for meals. In correlation analysis of the general characteristics and reasons for visiting, there were significant differences according to gender (p<0.01) and major study area (p<0.005). During visits the factor considered most important relative to the surroundings was food styling. The factors valued most highly when selecting a family restaurant were "good taste" (43.5%) and "good discounts" (26.3%) respectively. The favorite family restaurant was Outback Steakhouse (34.7%), and 86.4% of repliers had used a membership card, with 46.9% being satisfied with using the membership card. The conditions for using a family restaurant and satisfaction differences in each category, included: the amount of food (p<0.1) for the number of visits, taste (p<0.01), food shape and styling (p<0.05), surroundings (p<0.1), and interior (p<0.05): and for the meal fee per person, price (p<0.05) and sanitation (p<0.05), all showing significant differences as reasons for using the restaurants. In the factor analysis of nine categories, three factors: service, food, and economics were acquired, and their Cronbach's ${\alpha}$ values were 0.778, 0.671, and 0.587. Satisfaction toward food and service had a positive correlation of 0.457. Satisfaction toward food and economics increased a family restaurant's overall satisfaction score, and satisfaction toward service did not have a significant influence.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.192-211
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• 2021

In Seongju, Gyengsangbuk-do, the Placenta Chamber (胎室, Taesil) of 18 sons and a son of the crown prince of King Sejong(世宗大王) is located in one place. Taesil refers to the place where the umbilical cord and placenta, which are separated when the baby is born, are placed in a jar made of pottery and stone box and then buried on the ground. The placenta chamber in Seongju has the Buncheong ware (粉靑沙器) cover buried on the ground to protect the baby's placenta. These covers are all hemispherical, with a diameter of more the 20cm. The decorations were made using black and white inlaid techniques only on the outside. The Buncheong ware cover with this shape and pattern has been confirmed only in the placenta chamber in Seongju. This study targets 6 of the Buncheong ware cover whose owners were identified, when and where they were prepared, what the stylistic features and meanings are, and where it was produced. The results of the study are as follows. First, ss a result of reviewing the production background and procurement system of this bowl, it was inferred that it was sourced from Jangheunggo (長興庫) at the central government office, between 1436 and 1439, when the event to bury the placenta of royal members in the ground was the most active. Second, it analyzed the unique features of this cover, such as the shape, pattern, and baked traces. The shape and pattern were compared to the ritual objects contained in the Sejong Silok Oryeui (『世宗實錄』 「五禮」, Five Rites of King Sejong Chronicle) and the lid of the royal placenta jar made in the 15th and 16th centuries. Third, this study suggests that the baking method was based on the shape and location of the traces remaining outside the cover. Finally, the following data were used to estimate the production site: the relationship with the 'Jagiso (磁器所, ceramic workshop) registered in the Sejong Silok Jiriji (『世宗實錄』 「地理志」, Geographical Appendix of King Sejong Chronicle); various records of contribution and dedication about the Buncheong ware made here; and the Buncheong ware and related tools excavated from the kiln site in the area. The place where the Buncheong ware cover was produced is estimated to be the most likely production site for the kiln site in Chunghyo-dong Kiln Site, located in Jeolla-do province by synthesizing the data above.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.68-89
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• 2021

In August 1837, a list of wedding gifts was given by Queen Sunwon (1789-1857) to her son-in-law, Namnyeong-wie, Yun Eui-Seon (1823-1887) at the wedding of Princess Deok-on (1822-1844). This Honsubalgi is now kept at the National Hangeul Museum. This text was used in the present study to examine the everyday clothes of the royal son-in-law in the early 19th century. First, the everyday clothes were organized into about 36 types. They were classified as tops, bottoms, hats, accessories, belts, pouches, fans and shoes. Second, the most important clothes were the ordinary formal attire, composed of the namgwangsa dopo and namgwangcho changui. As for the bottoms, the pants, the Chinese hemp leggings, two pairs of socks, the green silk belt, and a pair of light blue ankle ties were identified. Third, as for the head and accessories, there were heukrip, with the gemstone string and silk string, the jeong-ja-gwan and dong-pa-gwan, as well as tang-geon and bok-geon. And there were the sangtu-gwan, three types of donggos, and the mang-geon equipped with okgwanja. On the other hand, the jeong-ja-gwan and dong-pa-gwan are peculiar hats whose status has changed over time since the mid-18th century. The fact that the jeong-ja-gwan and dong-pa-gwan were given to Namnyeong-wie showed that the status of these hats improved in the early reign of King Heonjong. The belt was given with the sejodae that is suitable for the dangsang, the coral plates, and the silk bag containing a flint pouch. Fourth, there were the red-colored sejodae, a ssamji silk pouch for flint and the fan decorated with okseonchu, and shoes, such as unhye and danghye.

• Korean Journal of Heritage: History & Science
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• v.49 no.3
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• pp.52-77
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• 2016

A spirit tablet of king Guan Yu is enshrined in Donggwanwangmyo shrine[East Shrine of King Guan Yu], which houses 51 hanging boards. The hanging boards were written by the kings of Joseon Dynasty and envoys and generals of the Ming and Qing Dynasties. Most studies on hanging boards have been focused on the collections of the palaces but not on those in Donggwanwangmyo shrine. In this regard, this study researches the hanging boards of the kings' writings in the late Joseon period and analyzes their forms and contents. In terms of contents, it examines who made the boards, when they made them, and what brought them to make them, etc. This study analyzes the forms of hanging boards by types, used materials, and periodic transition of forms. The findings are as follows. First, Donggwanwangmyo shrine houses 7 pieces of hanging boards inscribed with kings' handwriting: one piece of King Sukjong, 4 pieces of King Yeongjo, and 2 pieces of Emperor Gojong. They are divided into two types: one is the name of the buildings and the other is the poems that the kings wrote regarding what they felt when they visited the shrine. Especially, the latter were written by the kings who visited the shrine in spring and autumn. The kings intended to promote peace of royal family through a sense of royalty and fidelity of King Guan Yu. Second, the hanging boards of the kings are differentiated from those of the envoys and generals of the Ming and Qing Dynasties in materials and forms. The background of the board is colored by blue, deep red lacquer color, and black lacquer color, which are more expensive than black color or white color. The hanging boards are embossed with the kings' handwritings and then colored with gold. The frame-style four-side hanging board is held at a 45-degree angle and painted with floral patterns and seven-treasure patterns in Dancheong technique. The left and right sides and the top and bottom sides of the board are decorated with Dang-cho pattern(Korean arabesque pattern). This style is called "quadrilateral"and considered the most classy and top-class among the other three ones. In conclusion, this study confirms the status of Donggwanwangmyo shrine with hanging boards inscribed with kings' handwritings as a political space where kings had interest and demanded their soldiers' royalty and fidelity. Research into the boards inscribed with the handwritings of envoys of the Ming Dynasty and generals of the Qing Dynasty, and the comparison of the styles and periodic transition of forms will be reserved for another study.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.208-227
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• 2013

Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

• Korean Journal of Heritage: History & Science
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• v.55 no.1
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• pp.85-110
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• 2022

This study investigates the production and use, development of Buncheongsagisang-gamunryongmunho, focusing on Buncheong Jar with dragon and cloud patterns(龍樽) in the early the Joseon Dynasty. The Buncheong Jar with dragon and cloud patterns(龍樽) which is the size of a large bottle as high as 50cm is a form of stability to have gorgeous decorativeness with the inlaid and stamped pattern. The Buncheongsagisanggamunryongmunho is the Buncheong Jar with dragon and cloud patterns(龍樽) used for Flower Vessels(花樽) at Royal Ritual in King Sejong(世宗) era. In the 1420s and 1430s, made in Premium ceramic factory of Sangju-mok, it is Blue and white porcelain in reference to dragon and cloud patterns in the Yuan and Ming Dynasties in aspects of shapes and patterns, to the inlaid Celadon in the period of Late Goryeo Dynasty in aspects of patterns, and to Joseon porcelain in aspects of shapes and decoration techniques. The Joseon Royal family found out the appropriateness of the founding of the dynasty and the base for the system of civilization from Ming dynasty, to follow Ming dynasty by choosing white porcelains as the King's vessel. Jars passed down from Emperor Ming served as a standard for Royal Ritual Jars, to use Blue and White Porcelain Jar with dragon and cloud patterns as Flower Vessels(花樽) and Liquor Vessels(酒樽) for ages. Consequently, the Buncheong Jar with dragon and cloud patterns(龍樽) as Royal Ritual Jar had been used till 1430's when Blue and white porcelain Jar with dragon and cloud patterns(靑花雲龍白磁酒海) was passed down from Emperor Ming, Xuande Emperor(宣德帝), only to lose its Meaning and Use as the Royal Jar with dragon and cloud patterns(龍樽) during the early Joseon Period gradually.