• The Korean Journal of Zoology
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• v.8 no.1
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• pp.1-7
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• 1965

The short-necked clam is distributed widely in Korean tidal flats and it is a much an important bivalve quantitatively as to control the production of the tidal flat. The shell of this clam tends to show remarkable morphological variations depending on the habitat. Under a seemingly favorable condition for the growth , the color pattern of shell of the clam is clear and obvious and having less weight and elongated shape, the ratios of shell length to both height and width are small . On the contrary , when the environment appears to be an unfavorable one, the shell is found to be heavy and stunted with smudgy color pattern. If this correlation between could be a basis for the judgement in suitability of growth environment for the clam. In the Ikawazu Bay, Japan, it is revealed that the elongated shell is produced from the coast outside of the Bay (1) , the stunted from the esturay (2) and the intermediate from the floodgate area (3) and the middle of the Bay (4). Followings are the results obtained from the morphological investigation of the claim in this Bay. 1. Relationship between the shell length and the largest shell rib length is linear and between the shell length and the shell width is also linear but with a critical point at the shell length of 17-20 mm. The ratio between the width and the largest rib length at a given shell length increases with the order of 1, 3, 4, and 2. 2. A gradual decreases of the ratio of the shell length to the largest rib length is observed when the former is less than 17-18 mm, and this ratio increases with the shell of longer. Also there is a different range of this ratio in each different location ; the greatest range in 2, the smallest in 1 and 4 being in between. 3. A similar biometric finding is apparent with the ratio between the length and width of the shell and the order in value is 2, 4, 1 and 3. 4. The ratios between the length and the largest rib length of elongated and stunted shell are 0.84-0.86 and 0.89-0.92, respectively , and those between the length and width are 0.40-0.51 and 0.49-0.58, respectively. 5. Generally , the elongated short necked clam shells are products of the tidal flat of good circulation of sea water with high salinity and smaller fluctuations of salinity and temperature within a day. The stunted shells are produced for tidal flats of opposite of above conditions.

• The Korean Journal of Zoology
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• v.9 no.1
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• pp.7-15
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• 1966

In a previous paper, the dirunal and monthly changes of the tidal flat temperature and chlorinity were observed. In this paper the resistance of the young short necked clam in various growth stages to the temperature, to the chlorinity and to the exposure were studies. The young clam used were in early (E), medium (M) and late (L) young stages whose shell lengths were 2.0-3.5mm, 9.0-11.0mm. and 14.0-16.0mm., respectively. The results were : 1. At various sea water temperatures , the chlorinity resistance of the young clam was directly proportional to the shell length. 2. When both inadequate sea water temperature and abnormal chlorinity are simultaneously applied, the resistance of these young clams was more markedly reduced than the case of applying either one of these conditions. 3. In clams of M and L, no lethal effect were observed when daily immersion of four to eight hours for a week into the sea water of any concentration of chloriity at 26-34$^{\circ}C$, whereas in E, 37-90% of mortalities were obtained by immersion of eight hours daily into both the fresh water and the sea water of higher chloriniites (more than 23.5$\textperthousand$ Cl) at the same temperature above. 4. The lower critical thermal maximum for lethal to the young clam was 38$^{\circ}C$. With four hours immersion daily at the water temperature of 38$^{\circ}C$, the mortalities of E, M and L to the lower chlorinities (less than 6.7$\textperthousand$Cl) were 100, 70-100 and 27-37% respectively ; to the higher chlorinities (more than 23.5$\textperthousand$Cl) 10-70, 10-37 and 3 % respectively ; to the normal range of chlorinities (13.4-16.8$\textperthousand$Cl) 0-13, 3 and 0 % respectively. 5. No lethal effects were observed in E and M clams immersed continuously for seven days in sea water with chlornities of 7.2 -21.7$\textperthousand$Cl at 18-24$^{\circ}C$, while notable mortalities were observed in E which had been kept at lower (less than 4.8$\textperthousand$ Cl) and higher (more than 24.1$\textperthousand$ Cl) chlorinites. 6. Although the resistance of the young clam to the chlorinity may have to be related closely to the life history of the clam prior subject to the experiment, the adapted chlorinity range was 7.2-19.3$\textperthousand$ Cl and the optimum range was 13.4-16.8$\textperthousand$Cl. 7. Remarkable lethal effects were observed for the E and M clams to the exposure temperature of 38$^{\circ}C$ whereas the L and had no such fatal results.

• Journal of the Korean Home Economics Association
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• v.45 no.1
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• pp.63-73
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• 2007

Korean children's clothes have unique aesthetic characteristics distinguished from other countries'. Our folk beliefs handed down from ancient times always contained fortune - seeking thoughts and particularly mothers' earnest wishes for the happiness of their children were sublimated into the symbolic beauty of their children's clothes. The present study examined children's clothes in the royal family and among the people for 50 years of the transitional period from the late Joseon Dynasty to modern times, by classifying them into ritual dress for new-born babies, festival dress and everyday dress. Male children's clothes included caps such as Bokgeon(복건), Hogeon(호건) and Gulle(굴레) topcoats such as Durumagi(두루마기), Sagyusam(사규삼) Koija(쾌자) and Jeonbok(전복) and others such as Magoja(마고자), Baeja(배자), Joggi(조끼) and Bajijeogori(바지저고리), Female children's clothes included caps and head ornaments such as Gulle, Jobawi(조바위) and Daenggi(댕기) and others such as Durumagi, Jegori and Chima(치마). What is interesting is that old clothes handed down to the present are mostly boys' and few of them are girls'. This is probably because of the strong preference for boys rather than girls that continued until the end of the 20th century. Ordinary people dressed their new - born babies with simple white clothes until Samchilil (the 21st day) or Baekil (the 100thday) but, for these occasions, the royal family prepared clothes as formal as those for the $1^{st}$ birthday among the public. Rainbow-striped garments were more popular among the public than in the royal family. As rainbow colors were known to Korean people to dispel evil power and bring in fortunes, rainbow - striped garments were essential for the $1^{st}$ birthday and festive days. However, they were seldom used in ordinarytimes, and most boys and girls wore plain jackets and plain topcoats. When children's clothes in noble families were compared with royal family's ones, either handed down to the present or found in old literature, no significant difference was observed in the basic composition of everyday dress. In particular, it was found that Andong Kim's family had dressed their children with very formal dress such as Dopo and Sagyusam. Among children's clothes, the most gorgeous one was that worn on the $1^{st}$ birthday, and those for other occasions or festive days were similar or simpler. Colors, patterns and designs used in decorating children's clothes mostly had the meanings of seeking fortunes for children such as long life, wealth and prosperity.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.2
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• pp.93-100
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• 2022

The collision behaviors of the tripod and jacket structures, which are considered as support structures for offshore wind towers at the Southwest sea of Korea, were compared by nonlinear dynamic analysis. These structures, designed for the 3 MW capacity of the wind towers, were modeled using shell elements with nonlinear behaviors, and the tower structure including the nacelle, was modeled by beam and mass elements with elastic materials. The mass of the tripod structure was approximately 1.66 times that of the jacket structure. A barge and commercial ship were modeled as the collision vessel. To consider the tidal conditions in the region, the collision levels were varied from -3.5 m to 3.5 m of the mean sea level. In addition, the collision behaviors were evaluated as increasing the minimum collision energy at the collision speed (=2.6 m/s) of each vessel by four times, respectively. Accordingly, the plastic energy dissipation ratios of the vessel were increased as the stiffness of collision region. The deformations in the wind tower occurred from vibration to collapse of conditions. The tripod structure demonstrated more collision resistance than the jacket structure. This is considered to be due to the concentrated centralized rigidity and amount of steel utilized.

• Journal of Korea Port Economic Association
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• v.38 no.2
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• pp.11-30
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• 2022

Korean ports have some problems in the aspect of quality & quantity in the bunkering process. Quality of bunker is assessed as more higher than competing ports. However, quality of bunkering procedure is assessed as lower. Especially, supply chain from loading of bunker to the bunker barge at oil terminal, transport it, and supply it to the ship has not been secured. Furthermore, aspect of quantity of bunker is more serious rather than that of quality of bunkering process. Disputes on the quantity of bunker between seller and buyer occur frequently, and residue & theft of bunker is also popularized issue and serious problem. Low bunkering fee is recognized as major reason of that problem, however, though low fee can be solved, it can not be necessary secured that problem could be solved, Therefore, this paper investigates and suggests the scheme to solve the quality problems of bunker supplying procedure, and develop solution toward advanced bunkering ports through removal of the quantity disputes. Concretely, this paper suggests introduction of quality system of bunker supply chain in the aspect of bunker supply procedure, and diversion from conventional sounding method to innovative Mass Flow Metering System in the aspect of bunker measuring. These two innovative solutions contribute to the removal and improvement of current structural problems in bunkering procedure.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.2
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• pp.85-93
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• 2024

In this paper, we propose a method for establishing a state-space equation model for the motion analysis of floating structures subjected to wave loads, by applying system-identification techniques. Traditionally, the motion of floating structures has been analyzed in the time domain by integrating the Cummins equation over time, which utilizes a convolution integral term to account for the effects of the retardation function. State-space equation models have been studied as a way to efficiently solve floating-motion equations in the time domain. The proposed approach outlines a procedure to derive the target transfer function for the load-displacement input/output relationship in the frequency domain and subsequently determine the state-space equation that closely approximates it. To obtain the state-space equation, the method employs the N4SID system-identification method and an optimization approach that treats the coefficients of the numerator and denominator polynomials as design variables. To illustrate the effectiveness of the proposed method, we applied it to the analysis of a single-degree-of-freedom model and the motion of a six-degree-of-freedom barge. Our findings demonstrate that the presented state-space equation model aligns well with the existing analysis results in both the frequency and time domains. Notably, the method ensures computational accuracy in the time-domain analysis while significantly reducing the calculation time.

• Journal of Korean Home Economics Education Association
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• v.21 no.2
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• pp.23-43
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• 2009

This study examined the relativity between school uniform behavior(especially attitude toward school uniform, school uniform satisfaction, school uniform alteration) and attitude toward appearance in the adolescence. From November to December in 2007, 898 middle school and high school students from four schools in Jeollabuk-do Province were analyzed and the influence of relevant variables was understood to gather basic information about the fashion life in the adolescence. This study used SPSS 11.5 for Windows Program to conduct frequency analysis, factor analysis, reliability analysis, ${\chi}^2$-test, t-test, One-way ANOVA, Duncan's multiple comparison test, and Pearson's correlation. The following summarizes the findings of this study: The results of analysing the factors to the response attitude toward uniforms and attitude toward appearance and clothing attitude emerged four dimensions(fashion, symbolism, cleanliness, alternation), three dimensions(needs value conformity toward appearance). In attitude toward uniform, female students were more actively altering their uniforms than male students and middle school students were more sensitive to trends than high school students. However, high school students were more aware of the cleanliness and alteration of uniforms. Overall, most students were not very satisfied with their uniforms (design, color, texture). When students' attitude toward appearance and demographical characteristics were examined, it was found that female students were more aware of desire, value, and conformity in appearances than male students. By age, it was found that high school students were more aware than middle school students. Also, students receiving KRW 30,000 or more for monthly allowance were more aware than others who receive a lower amount between KRW 10,000 and KRW 20,000. Therefore, most students(62.1%) have experiences in altering uniforms. Especially, more female students and more high school students had such experiences. Uniform alteration is more related to attitude to appearance. In other words, students who choose to alter their uniforms are highly aware of desire, value, and conformity toward appearance. Students who are satisfied with all factors regarding attitude toward uniform, except for alteration, did not alter their uniforms that much. In addition, when the relativity between students' attitude toward appearance with uniform was considered, students that are not very satisfied with their uniforms were more aware of desire, value, and conformity toward appearance. In conclusion, it was found that students' attitude toward appearance and school uniform behavior are closely related and their interests in appearance lead to alteration of uniforms, the clothing in which they spend most time of the day. From now on, students' opinions shall be considered when selecting or designing school uniforms.

• Journal of the Korean Society of Costume
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• v.15
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• pp.177-194
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• 1990

Koh(袴) was a type of dress worn on the lower part of the body which was commonly used in the Northeast Asia. It was originally used by the Northern race for the need of nomadism or hunting. The origin of the Koh which appeared in the area would be found from the trousers of the Huns who influenced in the Northeast Asia, and became in the part of the Scythian culture. The Scythians are the nomadizing race inhabited in the Northern Caucasas on the wast of the Black Sea and influenced on the inland Eurasian steppe as the first typical horse-riding race. The objectives of Koh which had been worn in the Scythian, Mongolia, Korea as well as Japan as a part of Dongho dress and ornaments and to contemplate the transmission process by cultural exchange among different races for the period from 4th century to 7th century. 1. The Origination of the Koh The Koh was originated by the environmental factor to protect the cold in the North but also from the heat in the South, and was changed and developed as gradually satisfying to the needs of the times. In the Northeast Asia the Koh was in the class of the Northern Chinese garment, and was used widely by the horse riding Scythians who moved widely from the Eurasian inland to Japan. The oldest original which could reflect the type of the Northern clothes was a pair of trousers discovered in the Huns remains of Noin Ula. This showed the exact form of hunting clothes and had a similar form with the Korean female tro-users. Since the same form of trousers drawn on the wall painting of which was excavated 4-5th century ancient Koguryo(高句麗) tomb was the same form the trousers of Noin Ula seemed to be the original form of Koh in the Northeast Asia. 2. The Chinese Trousers It was the time of the King Mooryung(武靈王) in the Cho(趙) Dynasty B.C. 3th century that the trousers used regularly in China. However, the Koh had been used as undergarment which functioned for the protection of the cold not the horseriding garment. The trousers seemed to be not very obviously shown off since the Poh (袍) was long, but mainly used by the people from lower class. As people learned the adapted the trousers. It was essential for the times of war and quarrel. The king himself started wearing the Koh. The Chinese trousers were influenced by the Huns, the Northern clothes of the Scythian culture, and similar to the Korean clothes. 3. The Korean Trousers Korean was a race bared from the Eastern foreign group. It was obvious that the clothes was Baji-Jeogori(바지 저고리), the garment of the Northern people. This had the same form of the Scythian dress and ornaments which was excavated from the Mongolian Noin Ula. The Scythian dress and ornaments were influenced from the Ancient West Asia Empire and transmitted to the Northeast Koguryu by the horseriding Scythian. The trousers were kept in the traditional style by the common people in Korea were transmitted to Japan which were for behind in cultural aspect, as well as got used to the Chinese as the efficient clothes though active cultural exchange. 4. The Japanese Trousers The ancient Japanese clothes were influenced by the Southern factor but not the form of the Koh. As the Korean people group was moving towards Japan and conquer the Japanese in the 4-5th century, however, North Altaic culture was formed and at the same time the clothes were also developed. The most influenced clothes at this time were those of Baekge(百濟) and the trousers form called Euigon became the main form. Because of the climatic regional factor, it was tied not at the ankle but under the knee. From the view the ancient Japanese clothes disappeard about that time, it could be due to the conquest of the culturally superior race but not the transmission of the culture. In the latest 7th century both the Chinese and Japanese dress forms were present, but the Dongho(東胡) dress and its ornament from Korea was still the basic of the Japanese dress form.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.81-95
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• 2006

The purpose of this study was to evaluate appropriateness of clothing & textiles as educational contents in practical arts or technology home economics in the 7th curriculum. The factors of appropriateness were the amounts of learning, the degrees of understanding, interest and requirement on the educational content recognized by elementary, middle and high school students. The data collected from evaluation sheets were analyzed by frequency analysis, t-test, crossing analysis using SPSSWIN 12.0 program. Results were as follows; First. more than 50% of elementary, middle and high school students were recognized the amounts of tearing of clothing & textiles proper. But boy students of middle school recognized 'making clothes' in practice course too heavy. Second. It were from easy to difficult that the degrees of understanding on the educational contents of clothing & textiles recognized by elementary school students. Elementary school students understood both 'making cushion' and 'sewing machine theory and practice' difficult. Middle school students understood 'basic sewing for repairing clothes' and 'making clothes' difficult whereas high school students thought 'making pillow' and 'making bag' difficult. All students understood practice courses hard. Third, the degrees of interest showed from 'interest' level to 'not interest' level in case of elementary school students whereas 'interest' level in middle school students and 'common' in high school students. Fourth, the requirements of elementary, middle and high school students were in 'necessary' level to 'common' level. Editional contents such as 'learning sewing machine', 'making cushions'. 'making clothes', and 'making pillow-cover and bag' were low in the degrees of requirement. The correlationship between the amount of learning and the each level of understand, interest and requirement of students was indirect. On the other hand, Among the level of understand, interest and requirement were direct in case of high school students.

• Research in Plant Disease
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• v.25 no.3
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• pp.114-123
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• 2019

QD LED has an ideal light source for growing crops and can also be used to control plant pathogenic microorganisms. The mycelial growth inhibition effect of QD LED light on Rhizoctonia solani, Phytophthora drechsleri, Sclerotinia sclerotiorum, Sclerotinia minor, Botrytis cinerea, Fusarium oxysporum, Pectobacterium carotovorum, and Xanthomonas campestris were investigated. According to the results, BLUE (450 nm) light, suppressed S. sclerotiorum by 16.7% at 50 cm height from the light source, and 94.1% mycelial growth at 30 cm height. Mycelial growth of Sclerotinia minor was inhibited by 80.4% at 50 cm height and 36.3% at 50 cm height in B. cinerea. S. minor, and B. cinerea was inhibited by 100% mycelial growth at a height of 30 cm from the light source. At 15 cm height, all three pathogens (B. cinerea, S. minor, and S. sclerotiorum) was inhibited by 100%. QD RED (M1) and QD RED (M2) light suppressed mycelial growth of S. minor and B. cinerea by 100% at 30 cm and 15 cm height from the light source. For S. sclerotiorum, QD RED (M1) and QD RED (M2) showed 75.2% and 100% inhibition, respectively. Further experiment was conducted to know the suppression effect of lights after inoculating the fungal pathogens on lettuce crop. According to the results, QD RED (M2) suppressed the S. sclerotiorum by 59.9%. In addition, Blue (450 nm), QD RED (M1), and QD RED (M2) light reduce the infestation by 59.9%. In case of B. cinerea, disease reduction was found 84% by BLUE (450 nm) light. Results suggest that the growth inhibition of mycelium increases by Quantum dot LED light.