• Research in Plant Disease
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• v.10 no.4
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• pp.209-216
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• 2004

The circular leaf spot of persimmon is occurred almost every place where persimmon is cultivated, especially the disease outbreak severely in southern part of Korea. The disease reveals unusually long incubation period after pathogen invade into leaf tissue and no practical control measure is available once the symptom has appeared. Most of the farmers just follow the suggested spray schedules calculated on the basis of weather condition of ordinary years. Therefore the damages due to circular leaf spot greatly differ year after year. In this article, we tried to describe and summarized the investigation on the circular leaf spot pathogen, Mycosphaerella nawae, related to disease outbreak such as overwintering of pathogen, inoculum formation and spread, incubation period after infection, and secondary inoculum. With the summary of these results, we suggest the disease cycle of circular leaf spot of persimmon. The pathogen overwinters in diseased leaves as mycelial form or pseudoperithecial premodium. The pseudoperitheria become matured in spring as the temperature raise and forms asci and ascospores. The maturation of pseudoperithecia are closely related to the temperatures during March and early April. The ascospores completely mature in early May and the ascospores released when the pseudoperithecia absorbed enough moisture after rainfall. The release of ascospores are diverse greatly with the variation of maturity of pseudoperithecia. Generally the spore start to release from middle of May to early of July. Duration of ascospore release is depend on the weather condition of particular year, especially amount and number of precipitation. The ascospores produced from pseudoperithecia is known to the only inoculum for circular leaf spot disease. But according to the results obtained from our investigations, the conidia formed on the lesions which incited by natural infection. This conidia are infectious to persimmon leaves and formed identical symptom as natural infection. The time of producing secondary inoculum of circular leaf spot of persimmon is considered too late to develop new disease. Generally the importance of secondary inoculum is low but the conidia produced in early September are competent to develop new disease and new infection also significantly affect to harvest of persimmon. The importance of circular leaf spot disease is recognized well to farmers. The approaches to control of the disease should be initiated on the basis of the knowledges of inoculum dynamics and ecology of disease development. The forecasting system for circular leaf spot is need to be developed.

• Korean Parent-Child Health Journal
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• v.3 no.2
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• pp.49-66
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• 2000

Pregnancy is a task of creation in which a women mobilizes her self and the resources available to her in the generation of a new person. Through the pregnancy, a mother has formed the new human relationship with a fetus. Maternal-fetal relationship is considered one of mechanism making the relationship of mother and child. It is important to well-being of mother and fetus, too. The earliest interaction between a mother and her child is during prenatal period. Maternal-fetal dyad is unique and perceived interactions with the fetus make the pregnancy real for the mother. Maternal behavior is "instinctive" and is formed in early childhood by copy of the mother. But, Rubin argues that this behavior is an open intellectual system rather than a prepackaged bundle of traits. There is openness to new learning and a high value placed on knowing which occurs with silent organization in thought. Thus, nurses and other health professionals provide prenatal care that optimally is part of the environment in which the maternal-fetal dyad develops. Thus it is appropriate for nurses to increases their understanding of the dyad and to explore ways to enhance its development. This study focusses on the interaction ability and response of fetus, and the maternal-fetal interaction. The research of fetal responses that involve physiological changes and motor movement have been shown to coccur to both external sensory stimuli and to maternal emotional states. The fetus does also have sensory capacity to be aware of some maternal behaviors, and the motor ability to respond in a way the mother can notice. Thus, very rudimentary interactions appear to be possible. Maternal awareness of fetal activity was supported by several studies. More interesting to the present study are description of maternal-fetal interaction and the finding that there appear to be levels of sensitivity to the fetus involved in maternal-fetal interactions. First, recognition comes that the fetus is separate from the maternal self. Next, the fetus engages in. Lastly, the parent may describe active interaction with the fetus, believing that mother and fetus are communicating on a meaningful level. Several interventions, developed to promote more active interaction between mother and fetus, have been reviewed. In general, the parents were taught to stimulate the fetus and to notice the fetus' responses. This type of intervention might increase the mother's sensitivity to her unborn baby, and she may have a head start toward learning how to res pond sensitivity to the newborn infant. Research In the area of maternal-fetal interaction is scarce. Sensitive behavior is construed as an appropriate and timely response to a signal of need from another person, but no such signal of need can be claimed regarding the fetus. The highest level of maternal-fetal interaction, therefore, might be based more on maternal representations of the imagined fetus than on factual evidence of fetal participation.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.63-69
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• 2000

In order to establish a micropropagation system for buffalo gourd (Cucurbita foetidissima ) and common milkweed (Asclepias syriaca), the effects of several plant growth regulators and culture temperature on shoot multiplication and rooting were investigated. In buffalo gourd, the greatest number of shoot from shoot tip culture and well growth of formed shoot were obtained on the MIS medium supplemented with 1.0 mg/L BA and 0.3 or 0.6 mg/L IAA. Whereas kinetin and 2iP were not effective for shoot multiplication in vitro. It was found that 22$^{\circ}C$ and $25^{\circ}C$ were suitable for shoot multiplication. Roots were easily formed by the addition of auxins, especially 1.0 or 2.0 mg/L IBA and 2.0 mg/L IAA. Over 90% of plants survived successfully after being transferred into the field. In common milkweed, BA was more effective than kinetin or 2iP for its micropropagation in vitro. The increased shoot weight and number of nodes per shoot were obtained on the medium containing 3.0 mg/L BA and 0.3 or 0.6 mg/L IAA. But 2iP promoted the shoot elongation. In addition. common milkweed was sensitive to culture temperature in vitro. Temperature around 22$^{\circ}C$ was favorable for shoot multiplication and growth, whereas temperature higher than $25^{\circ}C$ usually reduced the rate of shoot survival rate.

• Journal of the Korean Geographical Society
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• v.21
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• pp.16-37
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• 1980

The purpose of this study is to clarify how the Korean tobacco farming region has been geographically formed by natural and cultural environments, and to examine and cultural environments, and to examine whether it can be recognized as a major part of agricultultural regions. The questions asked in this study are associated with the spatial diffusion of tobacco cultivation, the patterns and processes of the farming region from 1900 to 1960, and the regional characteristics of the concentrated farming area since 1960. The study is inductively approached and most data used were collected from old records and field works. The delineation of the tobacco farming region was derived by applying the concept of the uniform region. Tobacco was introduced through Japan during the years of Kwang Hae Kun (1616-1622). According to the old records, three places, Waekwan, Dongrae, and Ulsan, were the first tobacco raising areas. In the 1700's the well-known tobacco farming regions were scattered all around the nation in places like Jinan, Samdeung, Seongcheon, Gangdong, Yeongweol and Yeongyang. This distributon pattern suggests that tobacco farming in Korea developed spatially along main traffic routes before the 1700's. Untill the 1920's the pattern of tobacco regions was relatively static. Since the 1920's, it has shown a pattern of concentration in the Choongbuk province, where the new highly productive yellow tobacco has been introduced. It was not until the 1960's that yellow tobacco instead of the native variety came to be cultivated all over the country. In the 1960's, the tobacco farming region tended to be concentrated and localized in north western Choongnam, northern Cheonbuk, Choongbuk, and Kyeongbuk including Cheongsong, Andong, and Yeongyang. Since 1970, tobacco production has declined in some of the former major areas of cultivation in terms of its density, while there have appeared highly concentrated areas in Cheongsong and Andong, centered around Yeongyand. There has also emerged a secondary major concentrated area along the coast including such places as Kochang, Yeongkwang and Mooan. The appearance of the Yeongyang tobacco area as the most important core region can be described as follows; at first this area has the disadvantage of being in competition with other places for selling cash crops besides tobacco, because it is located in a mountain zone and it is far from the major metropolises of Seoul and Pusan. Thus has been formed the farming mentality that agricultural management makes the most profit on farming tobacco because tobacco is stable in price and selling routes. As a result of this longstanding belief, these areas (Yeongyang, Cheongsong and Andong) have developed into tobacco concentrated regions. Finally, the tobacco concentrated regions of Korea have changed through time. The factors affecting this change have been the kind of tobacco grown, the monopoly system, agricultural techniques and the expansion of arable land through the clearing of slopes. In conclusion, the research indicates that the localized and concentrated patterns of tobacco cultivation are geographically typical. Thus, recognition of tobacco farming region is important to understanding the agricultural region of Korea as a whole.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.100-113
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• 2007

In Korea, there has been no revegetation applicable standard for slopes formed by road construction work up to now, so revegetation work has been done using mostly foreign varieties in the manner of early revegetation. However, foreign varieties have some shortcomings; for example, they tend to be dried to death after construction work. Besides, due to the rift in the supporting soil, these revegetated varieties are often displaced from the slopes. Thus, the Ministry of Construction & Transportation on July, 2005 established revegetation standard on the slopes suited for the natural eco-system of Korea and organized positively recommending directions for using self-sewn plants growing near the slopes in overall consideration of soil, weather, regional conditions. The locations specified in this direction are the slopes at the road construction jobsite like the expressway, highways, and local roads. In addition, the Ministry's standard and directions stipulated that damaged slopes's natural environment and eco-system due to various road construction work should be restored, and thus a feeling of stability and pleasantness should be provided to road users as well. Also, the Ministry tried to select seed plants and revegetation measures suited for surrounding environment to put the environment-friendly slope revegetation measures into practice through the test revegetation work in order to prevent illegal construction practices and to improve the quality of revegetation. According to the direction, revegetation districts aimed at the slopes are divided into three ones in consideration of weather environment, regional environment, and forest environment as follows : national territory's core ecological green-land based district centering on the Taebaek Mountains; coastal ecosystem district including islands off the coast; inland eco-system district. The combination of revegetation plants according to environment revegetation districts, should be executed by dividing into herb-oriented type, woody plant colony type, and bio-species versatility restoration type, and the selection of seeding plants should be done in the presence of a supervisor and through test construction results and technology counseling from a specialist in natural eco-system restoration and revegetation measure seed combination standard according to environment revegetation districts. This direction will be executed in the manner of monitoring until the yea 2008 and 2009 it will be finalized and enforced on December, 2009.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.85-98
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• 2008

Calc-silicate rock sheet occurs within the Precambrian metasedimentary rocks in Bonghwa area, Kyungsangbuk-do, Korea. The calc-silicate rock runs parallel to bedding plane with $14{\sim}18$ meters in width. Calcite, dolomite, serpentine and tremolite are occurred as major minerals and talc is occurred as a miner mineral. Serpentine mainly occurs in the upper part and tremolite occurs in lower part of calc-silicate rock sheet. Colors of calc-silicate rock change to deeper green with increasing amounts of serpentine mineral. XRD, FT-IR analyses indicates that serpentine mineral is antigorite. Platy structure of antigorite is well observed by SEM analysis. EPMA data indicates that chemical composition of antigorite is very close to ideal ($SiO_2$: 44.3 wt% and MgO: 40.8 wt%). The chemical formula of antigorite is calculated as $Mg_{2.82}Al_{0.04}Fe^{3+}_{0.04}Si_{2.05}O_5(OH)_4$. From careful study by comparing mineralogical analysis data and occurrence, calc-silicate rock sheet was formed by metamorphism of calcareous sedimentary rocks having different mineralogical and chemical compositions. It is considered that the host rock of serpentine enriched upper part was more Mg-rich rocks than the host rocks of tremolite enriched lower part.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.12-20
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• 2015

The public employers are faced the mounting importance of decision process to settle the optimum VE delivery system of such public facilities buildings and etc. The elements of decision process of the public employer are formed in the various relationships of the concerned and when the projects are coming into effect, the decision process in the VE delivery method and the selection of contractor will be the name of the game. The decision process in the VE delivery method and the selection of contractor are created a case to be one and the same as well as initiates a consistency for the performance. However, the function and role of the public employer are projective accordingly to the organization of employer and the employer especially no system is equal to the capability of perfect evaluation and verification of the ability of the employer. Especially the lowest bidder policy that started with justification to increase the competitiveness and technical capability of the contractors through the completion in between contractors has been providing the hotbed for insolvency, irregularity and irrationality as a result. From this point of view it is declared that the buildup the edifice of supporting system in the process of decision to recover the mutual trust and respect of the concerned in the VE delivery system with the technostress and the systematization based on drawing the elements which affect the decision process of public employer.

• Journal of the Korean Electrochemical Society
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• v.11 no.2
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• pp.100-104
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• 2008

Titanium sheet metal substrates used in thin film batteries were wet etched and their surface area was increased in order to increase the discharge capacity and power density of the batteries. To obtain a homogeneous etching pattern, we used a conventional photolithographic process. Homogeneous hemisphere-shaped wells with a diameter of approximately $40\;{\mu}m$ were formed on the surface of the Ti substrate using a photo-etching process with a $20\;{\mu}m{\times}20\;{\mu}m$ square patterned photo mask. All-solid-state thin film cells composed of a Li/Lithium phosphorous oxynitride (Lipon)/$LiCoO_2$ system were fabricated onto the wet etched substrate using a physical vapor deposition method and their performances were compared with those of the cells on a bare substrate. It was found that the discharge capacity of the cells fabricated on wet etched Ti substrate increased by ca. 25% compared to that of the cell fabricated on bare one. High discharge rate was also able to be obtained through the reduction in the internal resistance. However, the cells fabricated on the wet etched substrate exhibited a higher degradation rate with charge-discharge cycling due to the nonuniform step coverage of the thin films, while the cells on the bare substrate demonstrated a good cycling performance.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.380-381
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• 2012

Bioinspired sea urchin-like structures were fabricated on silicon by inductively coupled plasma (ICP) etching using lens-like shape hexagonally patterned photoresist (PR) patterns and subsequent metal-assisted chemical etching (MaCE) [1]. The lens-like shape PR patterns with a diameter of 2 ${\mu}m$ were formed by conventional lithography method followed by thermal reflow process of PR patterns on a hotplate at $170^{\circ}C$ for 40 s. ICP etching process was carried out in an SF6 plasma ambient using an optimum etching conditions such as radio-frequency power of 50 W, ICP power of 25 W, SF6 flow rate of 30 sccm, process pressure of 10 mTorr, and etching time of 150 s in order to produce micron structure with tapered etch profile. 15 nm thick Ag film was evaporated on the samples using e-beam evaporator with a deposition rate of 0.05 nm/s. To form Ag nanoparticles (NPs), the samples were thermally treated (thermally dewetted) in a rapid thermal annealing system at $500^{\circ}C$ for 1 min in a nitrogen environment. The Ag thickness and thermal dewetting conditions were carefully chosen to obtain isolated Ag NPs. To fabricate needle-like nanostructures on both the micron structure (i.e., sea urchin-like structures) and flat surface of silicon, MaCE process, which is based on the strong catalytic activity of metal, was performed in a chemical etchant (HNO3: HF: H2O = 4: 1: 20) using Ag NPs at room temperature for 1 min. Finally, the residual Ag NPs were removed by immersion in a HNO3 solution. The fabricated structures after each process steps are shown in figure 1. It is well-known that the hierarchical micro- and nanostructures have efficient light harvesting properties [2-3]. Therefore, this fabrication technique for production of sea urchin-like structures is applicable to improve the performance of light harvesting devices.

• Journal of the Korean Ceramic Society
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• v.49 no.3
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• pp.247-252
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• 2012

Crystal structure and chemical compositions of Plasma electrolytic oxidized layer of A-1100, A-2024, A-5052, A-6061, A-6063, A-7075, ACD-7B and ACD-12 were investigated. The electrolyte for plasma electrolytic oxidation was mixture of distilled water, $Na_2P_2O_7$, Cu, Cr metal salts and KOH. ${\eta}$-Alumina, as well as ${\alpha}$-alumina, was main crystal phase. Another crystals such as $(Al_{0.948}Cr_{0.052})_2O_3$ and $(Al_{0.9}Cr_{0.1})_2O_3$ were also formed in the oxide layer. It was thought that the effect of electrolyte compositions on the physical properties and crystal system of PEO layers was greater than the effect of Al alloy composition variation.