• Geomechanics and Engineering
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• v.22 no.2
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• pp.173-185
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• 2020

Calcareous soil is originated from marine biogenic sediments and weathering of carbonate rocks. The formation history for calcareous sediment includes complex physical, biological and chemical processes. It is preferably selected as the major fill materials for hydraulic reclamation and artificial island construction. Calcareous sands possess inter pores and complex shape are liable to be damaged at normal working stress level due to its fragile nature. Thus, the engineering properties of calcareous soil are greatly affected by its high compressibility and crushability. A series of triaxial shear tests were performed on calcareous sands derived from South China Sea under different test conditions. The effects of confining pressure, particle size, grading, compactness, drainage condition, and water content on the total amount of particle breakage for calcareous soil were symmetrically investigated. The test results showed that the crushing extent of calcareous sand with full gradation was smaller than that a single particle group under the same test condition. Large grains are cushioned by surrounding small particles and such micro-structure reduces the probability of breakage for well-graded sands. The increasing tendency of particle crushing for calcareous sand with a rise in confining pressure and compactness is confirmed. It is also evident that a rise in water content enhances the amount of particle breakage for calcareous sand. However, varying tendency of particle breakage with grain size is still controversial and requires further examination.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.147-151
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• 2017

Areas of concentrations that can be exploited at all times, such as gas reservoirs in crude oil tanks, are called zero zones. In order to use various equipment in Zone 0, an intrinsically safe certification must be obtained that can guarantee that sparks will not occur in nature. Most devices that acquire intrinsic safety certification are mostly simple single-component devices or devices. In this study, it was a very difficult process because we intend to acquire the intrinsic safety certification of an electronic circuit including an ultrasonic generator and a microcontroller in which hundreds of components are mounted on a PCB substrate. Through this study, we have been able to understand how to design a circuit for intricate intrinsic safety certification. and Using the results of this study, it will be easier to design intrinsically safe circuits when trying to develop a circuit that can obtain intrinsic safety certification.

• ALGAE
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• v.35 no.3
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• pp.213-224
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• 2020

The freshwater red algal genus Sheathia contains species with heterocortication (both bulbous and cylindrical cells covering the main axis) and homocortication (only cylindrical cells). When the genus was proposed, the species with heterocortication were revised, but all specimens with homocortication were assigned to Sheathia arcuata with the caveat that it may represent a species complex. Recent studies have described new species with homocortication and S. arcuata has been rendered paraphyletic. In the current study, new sequences of the rbcL and 5′ region of the cytochrome c oxidase subunit I markers were combined with previously published data to construct a robust phylogeny and circumscribe new species. Four new species, S. abscondita, S. californica, S. plantuloides, and S. transpacifica are proposed. Examination of morphological characters among homocorticate species show no diagnostic characters to distinguish among species, whereas S. plantuloides is only known from sporophytes (chantransia) so it lacks the typical morphological characters derived from the gametophytes for comparison. Although DNA sequence data would be needed to make a positive species identification, geography could be employed to narrow the identification to one or two species. The genus is geographically widespread having been recorded from oceanic islands and five continents, whereas the individual species typically occur on a single continent. With this study, the number of species recognized in Sheathia is raised to 17; seven heterocorticate and 10 homocorticate, making this genus one of the most species rich in the Batrachospermales. As well, the resulting phylogeny provides insights into the evolution of heterocortication in Sheathia.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.2037-2047
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• 1991

Strength is not simply a single given value but rather is a statistical one with certain distribution functions. This is because it is affected by many unknown factors such as size, shape, stress distribution, and combined stresses. In this study, a model of loss probability is proposed in view of the fact that one of the fundamental configuration of nature is hexagonal, for example, the shapes of lattice unit, grain, and so on. The model sues the concept of loss of certain element in place of Jayatilaka-Trustrum's length and angle of cracks. Using this model, the loss probability due to each loss of certain elements is obtained. Then, the maximum principal stress is calculated by the finite element method at the centroid of the elements under the tensile load for the 4,095 models of analysis. Finally, the failure probability of the brittle materials is obtained by multiplying the loss probability by the ratio of the maximum principal stress to theoretical tensile strength. Comparison of the result of the Jayatilaka-Trustrum's model and the proposed model shows that the failure probabilities by the two methods are in good agreement. Further, it is shown that the parametric relationship of semi-crack lengths for various degrees of birittleness can be determined. Therefore, the analysis of the failure probability suing the proposed model is shown to be promising as a new method for the study of the failure probability of birttle materials.

• Journal of Environmental Impact Assessment
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• v.12 no.3
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• pp.137-150
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• 2003

This study aims to survey whether local governments have legislated laws and regulations on environment impact assessment system, to compare and analyze specific projects and their scale, assessment items, and procedures & discussion process, to identify issues and generate improvement plans, and to suggest a direction for future legislation to local governments that plan to legislate laws and regulations in the future. Major outcome of the study are as follows. First, terminologies used for environment impact assessment by local governments need to be unified. Also, laws and regulations need to be legislated soon. Second, in "urban development project" areas, a total of nine project areas including "quarrying of soil and stone, sand, gravel, and minerals" was essential common projects. A total of six project types were added or newly established compared to national systems. Among them, four project types were added within national-level project areas and two project types were not available under the national-level project areas and newly added due to the nature of local governments. Third, in terms of project scale, scale enhancement of "urban development project" was most common. Analysis showed that in case of clean natural environment such as Cheju Island, it is necessary to consider reinforcing project areas where development activities take place directly in forests or rivers such as "industrial base and complex development", "water resource development", and "development of tourism complex." Fourth, the discussion and review procedures of assessment reports were similar to those at government level. However, in case of Seoul city, it is required to write a "preparation plan" before drafting an assessment report. The city features partial introduction of scoping and screening, which allows to exempt discussion procedures if impact on environment is found to be minimal after drafting the assessment report. In case of national-level, it has a dual system that is split between Ministry of Construction and Transportation and Ministry of Environment. However, in case of environment impact assessment of local governments, it is a single system where city mayors and provincial governors are in charge of both project execution and environmental assessment. Therefore, the most important task is how to satisfy objectiveness and accountability.

• The Korean Journal of Cytopathology
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• v.9 no.2
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• pp.213-219
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• 1998

Glycogen-rich clear ceil carcinoma of the breast is an unusual variant of carcinoma with a recorded incidence of $1.4{\sim}3%$ of breast carcinomas. The cytologic characteristics have not been well described. We report two cases of glycogen-rich clear cell carcinoma with corresponding fine needle aspiration(FNA) cytologic findings and compare them to infiltrating ductal carcinoma and other clear ceil malignancies with a review of literature. One was a 62-year-old woman exhibiting a palpable mass of the right breast. The smears showed atypical tight cell clusters and individually scattered single cells containing leanly or clear abundant cytoplasm with well defined cytoplasmic margins. Mild to moderate nuclear pleomorphism and a prominent nucleolus were present. The other was a 42-year-old woman who was admitted with a right breast mass. The smears showed moderately cellular, tightly cohesive tumor cells. The cytoplasmic outline was generally well demarcated. The tumor cells Contained foamy to clear abundant cytoplasm with large and small vacuoles. The nuclear pleomorphism was marked. Both tumors resected by modified radical mastectomy, were diagnosed as glycogen-rich clear cell carcinoma. Histologically, the clear cell nature of tumor cells were not characteristic enough to predict this type of the tumor. Some cytologic features can be distinguished other clear cell breast cancer from glycogen-rich carcinoma. Recognition of these unusual patterns in a breast FNAC should raise the suspicion of a clear cell carcinoma including glycogen-rich subtype. Cytological localization of glycogen using PAS and D-PAS staining may permit the correct Identification and differential diagnosis of this tumor.

• The Plant Pathology Journal
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• v.18 no.2
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• pp.68-73
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• 2002

The influence of fungicidal spray was assessed on powdery mildew epidemics caused by Erysiphe polygoni D.C. and on yield-attributing characters of mungbean [Vigna radiata (L.) Wilczek]. Mildew attack adversely affected the yield-attributing characters of mungbean and exhibited negative significant correlation with pod length (-0.57), pods/plant (-0.74), pod weight (-0.68), 100 seeds weight (-0.69), 100 seeds swell weight (-0.59), and seed germination (-0.71). These characters had direct or indirect effects on grain yield, which was also adversely affected due to mildew attack (-0.89). Powdery mildew was significantly retarded due to the single spray of carbendazim (0.05%) at 30-day-old crop, where the apparent rate of infection (r) was minimum at 0.0095/ unit/day and with low (11.44%) powdery mildew intensity. Other fungicides like tridemorph (0.075%) and penconazole (0.05%) were equally effective against the mildew disease where the disease intensity was less than 20% and the values of r were 0.0134 and 0.039/unit/day respectively, as compared with the control at 0.267/unit/day. Fungicide spray influenced the yield-attributing characters besides controlling the disease. Such effects were more pronounced in carbendazim (0.05%)-treated plots due to its phytotonic nature where pod length (7.59cm), pods/plant (29.75), pod weight (8.16 g), 100 grain weight (3.94 g), and swell weight of 100 seed (9.49 g) were maximum resulting to the highest yield (480 kg/ha) as compared with that of control (224 kg/ha). Spray of carbendazim also improved seed germination (74.5%). Spray of other fungicides like carbendazim with copper oxychloride in 1:1 ratio, tridemorph (0.075%), and penconazole (0.05%) was equally effective against powdery mildew of mungbean. These fungicides also exhibited positive effects on yield-attributing characters of the crop and finally increased yield. These systemic fungicides were more effective in controlling powdery mildew disease of V. radiata in the rainy season compared with wettable sulphur.

• Korean Journal of Materials Research
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• v.25 no.9
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• pp.435-441
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• 2015

The ${\gamma}/{\gamma}^{\prime}$ two-phases, commonly known as a eutectic structure, are observed in the ${\gamma}$ interdendritic region of a Ni-base superalloy. However, the growth behavior of the ${\gamma}/{\gamma}^{\prime}$ two-phases, whether it is of eutectic or peritectic nature, has not been decidedly established. Directional solidifications were, thus, performed with the planar interface at a low growth rate of $0.5{\mu}m/s$ in order to promote macro segregation. Directional solidification started with the ${\gamma}$ planar interface and the ${\gamma}^{\prime}$ phase nucleated on the ${\gamma}$ planar interface at the solidification fraction of 0.75. The ${\gamma}/{\gamma}^{\prime}$ two-phases showed the ${\gamma}^{\prime}$ rod structure as major phase and the ${\gamma}$ minor phase between ${\gamma}^{\prime}$ rods, and the volume fraction of the ${\gamma}$ phase changed continuously with an increasing solidification fraction. The two-phase ${\gamma}/{\gamma}^{\prime}$ is seen as the coupled peritectic.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.75-82
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• 2010

Specific diseases like cancer and acquired immune deficiency syndrome (AIDS) occur at various organs including lymphatics and spread through lymphatic system. Thus, if therapeutic agents for such diseases are more distributed or targeted to lymphatic system, we can obtain several advantages like reduction of systemic side effect and increase of efficacy. For these reasons, much interest has been focused on the nature of lymphatics and a lot of studies for lymphatic delivery of drugs have been carried out. Because lymphatics consist of single layer endothelium and have high permeability compared with blood capillaries, especially, the studies using nano-sized carriers have been performed. Polymeric nano-particle, liposome, and lipid-based vehicle have been adopted for lymphatic delivery as carriers. According to the administration route and the kind of carrier, the extent of lymphatic delivery efficiency of nano-sized carriers has been changed and influenced by several factors such as size, charge, hydrophobicity and surface feature of carrier. In this review, we summarized the key factors which affect lymphatic uptake and the major features of carriers for achieving the lymphatic delivery. Lymphatic delivery of drug using nano-sized carriers has many fold improved ability of lymphatic delivery compared with that of conventional dosage forms, but it has not shown whole lymph selectivity yet. Even though nano-sized carriers still have the potential and worth to study as lymphatic drug delivery technology as before, full understanding of delivery mechanism and influencing factors, and setting of pharmacokinetic model are required for more ideal lymphatic delivery of drug.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.10
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• pp.1575-1589
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• 2009

Lifestyles of Health and Sustainability (LOHAS) is based on environmental social responsibility and has become important factor in fashion trends. This study was to correct the types of LOHAS fashion design systems and to analyze attributes based on a case study of LOHAS in the fashion industry and the inquiry into leading studies. This study was carried out and the visual research material was analyzed based on the data of: Internet sites and mediums of communication (literature in the field of design, newspaper, magazines, and TV); after the year 2000 a preceding study about LOHAS also provides a new concept. In addition, the types of LOHAS fashion design were arranged and considered based on analyzed special qualities of a LOHAS the notion. The types of LOHAS fashion design that could be divided into nine patterns are 1) environmentally friendly material practical use 2) re-design 3) message transmission 4) nature motive practical use 5) multi-function design 6) retrenchment design 7) the higher sensitivity pursuit design 8) order production 9) society-morals design. In addition, LOHAS fashion did not appear in any single emphasized special quality of independent type among these, but appeared as a mutually united special feature based on the consciousness of society-morals. It is known that expression is possible to combine into one fashion design with various types and it is possible for various uses.