• Journal of Ecology and Environment
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• 제32권1호
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• pp.33-39
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• 2009

Brood caring behavior was observed in Amaurobius ferox (Araneae, Amaurobiidae), a semelparous subsocial spider, from cocoon construction until the emergence of spiderlings from the cocoon. Unlike most spiders, which emerge from cocoon by their own means, A. ferox mothers intervene in the process of the emergence of their young. I manipulated broods by removing the mother prior to emergence to determine the effects of maternal behavior on the emergence of spiderlings. My results showed that maternal intervention making the cocoon expansion and its exit, is not absolutely necessary for the emergence of A. ferox spiderlings from the cocoon. Nine clutches out of ten were able to get out of the cocoon by their own means without their mother's help. There was no difference between control groups ('with mother') and experimental groups ('without mother') in the number of spiderlings that emerged ($96.9{\pm}25.3$ vs. $90.4{\pm}14.2$, respectfully) and in the time from the beginning to the end of emergence ($36{\pm}12$ vs. $41{\pm}17$ hours). Time from eclosion until the emergence of the first individual in a clutch, however, was greater in the mother-absent group (3.5 days) than in the control group (2.0 days). The construction of the cocoon by the mother required always occurred in the same area within the retreat, and took approximately 6 hours, and the mother guarded the eggs during the incubation period. The emergence of the spiderlings followed a sigmoidal pattern. After emergence, the spiderlings formed a very compact group on the cocoon, which may be important in securing maternal care. The absence of cribellum and calamistrum, structures likely involved in their survival, observed in individuals of the first instar suggests that in the first stage of life, the spiderlings are dependent on their mother.

• 산업경영시스템학회지
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• 제44권4호
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• pp.113-127
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• 2021

Topic modeling has been receiving much attention in academic disciplines in recent years. Topic modeling is one of the applications in machine learning and natural language processing. It is a statistical modeling procedure to discover topics in the collection of documents. Recently, there have been many attempts to find out topics in diverse fields of academic research. Although the first Department of Industrial Engineering (I.E.) was established in Hanyang university in 1958, Korean Institute of Industrial Engineers (KIIE) which is truly the most academic society was first founded to contribute to research for I.E. and promote industrial techniques in 1974. Korean Society of Industrial and Systems Engineering (KSIE) was established four years later. However, the research topics for KSIE journal have not been deeply examined up until now. Using topic modeling algorithms, we cautiously aim to detect the research topics of KSIE journal for the first half of the society history, from 1978 to 1999. We made use of titles and abstracts in research papers to find out topics in KSIE journal by conducting four algorithms, LSA, HDP, LDA, and LDA Mallet. Topic analysis results obtained by the algorithms were compared. We tried to show the whole procedure of topic analysis in detail for further practical use in future. We employed visualization techniques by using analysis result obtained from LDA. As a result of thorough analysis of topic modeling, eight major research topics were discovered including Production/Logistics/Inventory, Reliability, Quality, Probability/Statistics, Management Engineering/Industry, Engineering Economy, Human Factor/Safety/Computer/Information Technology, and Heuristics/Optimization.

• 복식
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• 제51권8호
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• pp.13-24
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• 2001

With development of our society, the Hanbok, which is the traditional clothing of our country, is mainly used only on the festive days or marriage ceremony or so as a ceremonial dress and seems lack in wearing as plain clothes. But in the other hand. with general public became no more unfamiliar with the representation of Korean realities and accepted them as a part of life in 90', the modernized Hanbok that features seasoning the practicality into the aesthetic natures of the traditional Hanbok has been rooting in our country. The existing researches on the modernized Hanbok, however. are focused only in the design of the modernized Hanbok, the present conditions of the modernized Hanbok business and the actual condition of the modernized Hanbok, and the aspect in systematic research on the customers'purchasing behavior is weak in comparison with other areas. The goal of this research, by focusing in the value which is the most basic concept of psychological components indicating the customers' behavior, was : first. to make clear the value of the modernized Hanbok and divide the customers into various groups : second, to make clear the characteristics on the population statistics by the groups divided on the clothing value : third, to make clear the individual differences among the customers of the modernized Hanbok : and forth, to make clear the basis on which to estimate the modernized Hanbok by the customers'groups. This research adopted the surrey inquiry. The first investigation is carried out on the modernized Hanbok purchasers and salesmen in Insa-dong where the modernized Hanbok business is massed. As correction and complement for the first investigation. the final investigation is carried out in Oct. 2000 with the 480 persons from twenties to sixties consisting of the modernized Hanbok purchasers and experienced persons in wearing it.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.186-186
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• 2012

This report investigates a new synthetic route and the size-dependent optical and electrical properties of PbS nanocrystal quantum dots (NQDs) in diameters ranging between 1.5 and 6 nm. Particularly we synthesize ultra-small sized PbS NQDs having extreme quantum confinement with 1.5~2.9 nm in diameter (2.58~1.5 eV in first exciton energy) for the first time by adjusting growth temperature and growth time. In this region, the Stokes shift increases as decreasing size, which is testimony to the highly quantum confinement effect of ultra-small sized PbS NQDs. To find out the electrical properties, we fabricate self-assembled films of PbS NQDs using layer by layer (LBL) spin-coating method and replacing the original ligands with oleic acid to short ligands with 1, 2-ethandithiol (EDT) in the course. The use of capping ligands (EDT) allows us to achieve effective electrical transport in the arrays of solution processed PbS NQDs. These high-quality films apply to Schottky solar cell made in an glass/ITO/PbS/LiF/Al structure and thin-film transistor varying the PbS NQDs diameter 1.5~6 nm. We achieve the highest open-circuit voltage (＜0.6 V) in Schottky solar cell ever using PbS NQDs with first exciton energy 2.58 eV.

• 대한가정학회지
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• 제38권12호
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• pp.73-84
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• 2000

This article is a continuing report about a development of disposable diapers for the elderly in need. In previous report, the first prototypes of disposable diapers in two different categories have been developed. One was a panty type and the other was a pad type. These prototypes were results of property test and wear test of existing disposable diapers in each categories. Yet, in order to develop useable products, the second property and wear tests using the first prototype diapers were carried out. Considering the resets of the second tests, enhancements to the first prototypes were made to refine the second prototypes. The panty type diaper were altered to be longer to prevent evacuation from leaking and fit better. The pad type diapers were altered to reduce thickness for comfort and wearing appearance when get dressed. Ultimately a lot more disposable diapers will be required in future. Resulting suggestions are as follows. Anthropometric data around hip area of elderly in both sexes have to be collected to give meaningful information to diaper manufacturers, so that they can manufacture for different sizes and different sexes. Also we suggests that diapers for specific disease such as diabetics have to be designed accordingly.

• 아시안잔디학회지
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• 제7권2_3호
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• pp.121-127
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• 1993

This experiment was carried out to compare the varietal differences of dry matter production in rend canarygrass. The varieties examined were Common, Venture, Castor, Palaton and Venture. Reed canarygrass was harvested three times annually, 1st cut(1O, May), 2nd cut(31, July), and 3rd cut(10, Oct.), respectively. The results were summarized as follows ; 1. Dry matter yield were not significant difference between varieties and for the interaction of variety$\times$cut. But, there was significant difference between cuts. 2. There was not significant difference in dry matter yield between the first cut and second cut. But, the dry matter yield of the third cut was poor than the other two cuts. Thus, the average dry matter yield of varieties were 806.1 kg, 730.8kg and 495.8kg /l0a in the first, second and third cut, respectively. 3. In Venture and Palaton, the percentage of dry matter distribution in spring was higher than that of other varieties. In Common, Castor and Vantage, they were not significantly different between the percentage of dry matter distribution in each cut. Above the results suggested that the first group of varieties(Venture and Palaton) were suited to meadow and last group of varieties(Common, Castor and Vantage) were suited to pasture. 4. Average total dry matter yield of varieties was 2,032kg /l0a/yr,(ranged from 1,922kg to 2,180 kg /l0a /yr.)

• 한국학교보건학회지
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• 제6권2호
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• pp.56-68
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• 1993

The primary school age are important period that the children exchange the deciduous teeth for permanent teeth, there are so many outbreak of dental caries which is major oral diseases periodontal disease begins, and malocclusion may be brought about. The purpose of this study is to suggest the fundamental data for enforcement of dental health in primary school age as analyzing the curriculum contents and amount on dental health in primary school course. The data were investigated from 103 volumes of 139 textbooks of second semester in 1992 and first semester i 1993 except some subjects that the quantitative analysis is impossible such as arithmetic a problem in arithmetic, observation, music, fine arts and so on. The contents of all textbooks were analyzed separating into paragraph and picture, the contents for dental health were classified into amount, item, teaching method. The results are as follows: 1) The paragraphs on public health were 3.992 among total paragraphs 69,789 as 5.72%. And the picture were 7.41% as 923 pieces of total 12,457 ones. 2) For dental health, there were 73 paragraphs of 69.789 ones (0.10%) and 42 pieces of 12.457 pictures (0.34%). 3) According to the investigation of curriculum that had the paragraphs related to dental health the most, it turned out to be in order of physical education nature. Right life story, and right life story, righ life, physical education for the picture. And for the grade, it appeared to be in order of sixth, third first grade for the paragraphs and first, third, sixth grade for the pictures. 4) In the attitude and knowledge of item for dental health by grade, it turned out that the paragraph was 76.71%, the behaviour was 23.29%. On the other hand, the knowledge was 35.17% and the attitude was 64.28% for the picture. 5) At the commentary of curriculum in primary school, the goal of health education by each grade was just keep clean and strong teeth, know the role of teeth and the cause of dacayed teeth, and prevent it in second and third grade.

• 한국경영과학회지
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• 제1권1호
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• pp.151-170
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• 1976

There are many cases of production processes which intermittently produce several different kinds of products for stock through one set of physical facility. In this case, an important question is what size of production run should be prduced once we do set-up for a product in order to minimize the total cost, that is, the sum of the set-up, carrying, and stock-out costs. This problem is used to be called scheduling of multiple products through a single facility in the production management field. Despite the very common occurrence of this type of production process, no one has yet devised a method for determining the optimal production schedule. The purpose of this study is to develop quantitative analytical models which can be used practically and give us rational production schedules. The study is to show improved models with application to a can-manufacturing plant. In this thesis the economic production quantity (EPQ) model was used as a basic model to develop quantitative analytical models for this scheduling problem and two cases, one with stock-out cost, the other without stock-out cost, were taken into consideration. The first analytical model was developed for the scheduling of products through a single facility. In this model we calculate No, the optimal number of production runs per year, minimizing the total annual cost above all. Next we calculate No$_{i}$ is significantly different from No, some manipulation of the schedule can be made by trial and error in order to try to fit the product into the basic (No schedule either more or less frequently as dictated by) No$_{i}$, But this trial and error schedule is thought of inefficient. The second analytical model was developed by reinterpretation by reinterpretation of the calculating process of the economic production quantity model. In this model we obtained two relationships, one of which is the relationship between optimal number of set-ups for the ith item and optimal total number of set-ups, the other is the relationship between optimal average inventory investment for the ith item and optimal total average inventory investment. From these relationships we can determine how much average inventory investment per year would be required if a rational policy based on m No set-ups per year for m products were followed and, alternatively, how many set-ups per year would be required if a rational policy were followed which required an established total average inventory inventory investment. We also learned the relationship between the number of set-ups and the average inventory investment takes the form of a hyperbola. But, there is no reason to say that the first analytical model is superior to the second analytical model. It can be said that the first model is useful for a basic production schedule. On the other hand, the second model is efficient to get an improved production schedule, in a sense of reducing the total cost. Another merit of the second model is that, unlike the first model where we have to know all the inventory costs for each product, we can obtain an improved production schedule with unknown inventory costs. The application of these quantitative analytical models to PoHang can-manufacturing plants shows this point.int.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권4호
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• pp.1987-2001
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• 2017

Low-density parity-check (LDPC) codes have attracted a great attention because of their excellent error correction capability with reasonably low decoding complexity. Among decoding algorithms for LDPC codes, the min-sum (MS) algorithm and its modified versions have been widely adopted due to their high efficiency in hardware implementation. In this paper, a self-adaptive MS algorithm using the difference of the first two minima is proposed for faster decoding speed and lower power consumption. Finding the first two minima is an important operation when MS-based LDPC decoders are implemented in hardware, and the found minima are often compressed using the difference of the two values to reduce interconnection complexity and memory usage. It is found that, when these difference values are bounded, decoding is not successfully terminated. Thus, the proposed method dynamically decides whether the termination-checking step will be carried out based on the difference in the two found minima. The simulation results show that the decoding speed is improved by 7%, and the power consumption is reduced by 16.34% by skipping unnecessary steps in the unsuccessful iteration without any loss in error correction performance. In addition, the synthesis results show that the hardware overhead for the proposed method is negligible.

• The Journal of Asian Finance, Economics and Business
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• 제9권5호
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• pp.409-419
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• 2022

This paper examines the post-IPO price volatility in the first trading days after the IPO of SOEs that carry out equitization, on a sample of 76 IPOs on the Hanoi Stock Exchange (Vietnam) in the period 2013-2018. Oversubscription rate, firm size, issuance size, internal equity ownership, and listing delay are all factors that influence IPO price volatility in a primitive stock market. The results showed that the average initial market-adjusted return for the first three trading days was -11.95%; -9.58% and -7.29% and the level of price volatility is related to the rate of oversubscription and company size. Issuance price, issuance size, internal equity holdings, and listing delay do not seem to contribute significantly to post-IPO share prices. Individual investors based their valuation on information released during and after the IPO. In general, the number of IPOs that yield positive and negative returns in the first trading days is about the same, indicating that the two phenomena of undervaluation and overvaluation still occur in the process of valuing shares of Vietnamese SOEs for IPOs.