• Journal of the Korean Electrochemical Society
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• v.25 no.1
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• pp.1-12
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• 2022

Lithium metal is the most promising anode for next-generation lithium-ion batteries due to its lowest reduction potential (-3.04 V vs. SHE) and high specific capacity (3860 mAh/g). However, the dendritic formation under high charging current density remains one of main technical barriers to be used for commercial rechargeable batteries. To address these issues, tremendous research to suppress lithium dendrite formation have been conducted through new electrolyte formulation, robust protection layer, shape-controlled lithium metal, separator modification, etc. However, Li/Li symmetric cell test is always a starting or essential step to demonstrate better lithium dendrite formation behavior with lower overpotential and longer cycle life without careful analysis. Thus, this review summarizes overpotential behaviors of Li/Li symmetric cells along with theoretical explanations like initial peaking or later arcing. Also, we categorize various overpotential data depending on research approaches and discuss them based on peaking and arcing behaviors. Thus, this review will be very helpful for researchers in lithium metal to analyze their overpotential behaviors.

• Women's Health Nursing
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• v.5 no.2
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• pp.222-229
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• 1999

These days, as the society has been in the trends of highly industrialized and the family has been downsized, there is remarkably increasing number of women who follow occupation. These changes have made it more difficult for the family to help post-partum mother, which had been performed in side of house. By the help of social believe that during at least 1 month after childbirth professional nursing program is indispensable for both maternity protection and physical-mental recuperation, now many post-partum care centers for post-partum mother have been in operation. Although these post-partum care center have in use for a long time, no study was performed before this study on the same subject. Data were analyzed using by SAS. The results of study are as follow : 1. The general features of the user of the post-partum care center. The predominant band of user's age is extended from 26 to 30. The users are mainly housewives and they are in higher level of incomes and educations. As for the feature of delivery methods, they performed the normal spontaneous vaginal delivery method by 58.0% and the Caesarean operation method by 42.0%. As for the sexuality for babies, 59.3% of infants are male, and 40.7% are female. The highest delivery order of users is first and admission after 1-3days delivery is highest. 2. The results for the investigation into the actual condition of the post-partum care center are as follow : About the main reason for entrance of the post-partum care center was found to be the needs for the better nursing programs for recuperation after childbirth. This demands are also supported by their husbands. The average length of stay in the post-partum care center is 17.6 days and the besides promised expense ; powdered milk, milk-suckers, disposable dippers, skin cares, body shape cares, entrophics, injections. The post-partum have private rooms for mother and infants. Over the half of average expense is 229 million won. They are paying accessory fees the post-partum care center have similar step organization : the nurses, the skin carers, the cleaners. Mostly both ways of feeding powdered milk and breast feeding are in use, and mother's milk is preserved in the night time to be given to infant by nurse in charge. 3. The results of the investigation on users' nursing demand to the post-partum care center and satisfaction are as follow : The ranking order of nursing demand of mothers who used the is that ; infant care demands, environmental demands, emotional and mental care demands, education and training demands. As much as 70% of the respondents have dissatisfaction in nursing program, The ranking order of service satisfaction of mothers who used appears to be higher following order ; satisfaction in infant care demand, satisfaction in physical nursing demand, satisfaction in emotional and mental nursing demand, satisfaction in education and training demand, satisfaction in environment nursing demand. The results of pearson correlation. between nursing demand and service satisfaction of mothers who used are found to be relative noticeable in the level of 0.05. only infant care. The 61.7% of the women who used the post-partum care center. are responding that they will reuse the same post-partum care center again.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.23-28
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• 2003

The present study was undertaken to investigate the effects of PVP concentration and exposure temperature to vitrification solution on the post-thaw survival, in vitro maturation and development of immature bovine oocytes (germinal vesicle stage). The vitrification solution (VS) consisted of 40% ethylene glycol (EG)+0.5 M sucrose (S)+10% FBS. PVP was added to VS: 0%, 5% or 10%. The cumulus-oocyte complexes (COCs) were diluted in VS as one step, after 2 min the COCs were loaded in straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were plunged into $30^{\circ}C$ water bath for 10s. After thawing, the oocytes were diluted in 0.5 M (in DPBS with 10% FBS) sucrose solution for 5 min. The survival rate (FDA-test and trypan blue) of immature bovine oocytes was measured. The survival rate was higher in 5% PVP (91.5%) than in 0% (64.2%) or in 10% PVP (79.7%). The proportion of metaphase II formation was 69.35% in control (no vitrified COCs), 9.3% in 40% EG+0.5 M S+0% PVP and 21.05% in 40% EG+0.5 M S+5% PVP (p<0.05). The effect of room temperature ($25^{\circ}C$ for 10 min) and cold temperature ($4^{\circ}C$ for 10 min) on COCs were determined in this study. After IVF, the cleavage and blastocysts rate of oocytes exposed to room temperature and cold temperature in VS+5% PVP was significantly different (2 cell: 63.20% vs 37.97%, blastocysts: 18.40% vs 2.53%). The cleavage rates of frozen-thawed oocytes were 20.53% with PVP and 22.13% without PVP (p>0.05). Two out of 151 oocytes (1.32%) developed to blastocyst stage after frozen-thawed with 5% PVP (p>0.05). Development of oocytes after frozen-thawing to the 2 cell were not significantly affected with or without PVP following IVF. However, the vitrification of immature bovine oocytes with PVP maintained the ability to develop to the blastocyst stage after IVM-IVF and IVC, while no blastocysts were obtained from oocytes vitrified without PVP. These results suggested that PVP has a protective role for vitrification of immature bovine oocytes as far as survival is concerned, however, the protection was not sufficient enough to support blastocyst formation.

• Journal of the Korean Geosynthetics Society
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• v.1 no.1
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• pp.13-21
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• 2002

Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(detached breakwater, groins and jetty). The geotextile tubes are made of sewn geosynthetics sheets. If the sandy soil is use to fill material, these inlets should be spaced closely to assure uniform filling of the tubes because sandy soil and geosynthetic is very pervious. However, the clayey soil or contaminated slurry is used, the inlets can be located relatively long distance. The fine clayey particles tend to rapidly blind the fabric slowing down water escape through the geotextile. This paper presents a field test result of a geotextile tube in the land reclamation project for the Songdo New City construction site. The dredged silty clay was dredged by the dredging ship and hydraulically pumped into the geotextile tube. The height of geotextile tube was measured at every filling stage and also measured width and diameter of geotextile tube with the elapsed time. Based on the test results, if the clayey filling material is used, the pumping step must be divided 3~4 stages for drainage and sediment. After complete drainage, the height of the geotextile tube reduces by approximately 50%.

• Korean Journal of Heritage: History & Science
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• v.49 no.1
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• pp.100-119
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• 2016

The concept of "original form" and the principle of "maintaining the original form" take center stage in conservation, management, and promotion of the domestic heritage. Introduced in the 20th century, there were little discussion or deliberation about the concept of "original form" therefore it remains a vague and somewhat abstract notion subject to individual interpretation. Without a specified practical meaning, "maintaining the original form" became the fundamental principle for heritage conservation and management in the 1999 version of the Cultural Heritage Protection Act, engendering difficulties in applying the principle in practice. Conceived as an important first step toward resolving the issues stemming from the indistinct concept of "original form," this paper explores the process through which the concept was introduced to Korea and then established and developed as a legal principle for heritage conservation, management, and promotion. While the examination of the related documents and various cases shows that the development of the concept of "original form" has centered on specific periods and architectural styles, this essay explicates that the notion "original form" is commonly used as a term referring to the form at the earliest possible temporality. It also explains that this view emanates from perceiving heritages not as multivalent objects, but as a material object that exclusively carries aesthetic and, more importantly, historical value, and that comes from the history awareness of the times. This essay suggests that the concept "original form" should be reestablished with full consideration of the diverse values of heritage and diverse forms through which heritage can be expressed. After reviewing the feasibility and practicality of the concept a set of concrete guidelines should be presented for application in practice.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.321-331
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• 2019

BACKGROUND: Pinoxaden is the phenylpyrazoline herbicide developed by Syngenta Crop Protection, Inc. and marketed on 2006. The maximum residue levels for wheat and barley were set by import tolerance. Thus, Ministry of Food and Drug Safety (MFDS) official analytical method determining Pinoxaden residue was necessary in various food matrixes. Satisfaction of international guideline of CODEX (Codex Alimentarius Commission CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) are additional pre-requirements for analytical method. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was investigated to analyze residue of Pinoxaden (M4), which is defined as pesticide residue in Korea, in foods. METHODS AND RESULTS: Pinoxaden (M4) was extracted followed by acid digestion (2hr reflux with 1N HCl) and pH adjusting (pH 4-5 with 3% ammonium solution). To remove oil, additional clean-up step with hexane saturated with acetonitrile was required to high oil contained sample before purification. HLB cartridge and nylon syringe filter were used for purification. Then, samples were analyzed by LC-MS/MS using reserve phase column C₁₈. Five agricultural group representative commodities (mandarin, potato, soybean, hulled rice, and red pepper) were used to verify the method in this study. The liner matrix-matched calibration curves were confirmed with coefficient of determination (r²) > 0.99 at calibration range 0.002-0.2 mg/kg. The limits of detection and quantitation were 0.004 and 0.01 mg/kg, respectively, which were suitable to apply Positive List System (PLS). Mean average accuracies of pinoxaden (M4) were shown to be 74.0-105.7%. The precision of pinoxaden and its metabolites were also shown less than 14.5% for all five samples. CONCLUSION: The method investigated in this study was suitable to CODEX (CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) guideline for residue analysis. Thus, this method can be useful for determining the residue in various food matrixes in routine analysis.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.2
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• pp.92-104
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• 2015

In order to analyze the impacts of climate change, a time and space integrated model was developed in this study using system dynamics and GIS. The model built was used to carry out a simulation on the inundation impact on A-gu of Busan Metropolitan city resulting from the sea level rise scenario of IPCC and storm surge, which is the worst case. Through this, the flooded area and population until 2100 were predicted. Also, the result and significance of each alternative was reviewed improving the model by establishing alternative scenarios of protection, accommodation and retreat as plans of reaction to sea level rise. The combination of system dynamics and GIS has advantages of how the diverse variables change until the target year can be traced and, accordingly, not only the results but also the processes of spatial change can be examined by calculating the value of change process at each time step. The synergy of this model presumed to be a foothold for solving problems which are becoming difficult to predict due to increase in uncertainty and complexity such as the support for decision making for urban resilience to natural disasters.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.170-187
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• 2006

The purpose of this study is to provide a basic datd for establishing a basic park management plan for Bulamsan Urban Nature Park. This research surveys very closely about the present condition of the natural ecosystem based on the examination and analysis of the present condition. This research suggests development and management methods for environment-friendly park by understanding damages on the ecosystem due to overuse, as well as park facilities and their effects on the surrounding environment, using quantative analysis. The three steps: researching the present condition research, ecosystem evaluation, and park management plan were taken in order. The present condition research is based on the general condition, natural environment, and natural ecosystem data. In the ecosystem evaluation, wildlife habitats evaluation, landscape evaluation, and biotope type research which is a materialized form of the plant ecosystem were excuted based on the present condition research data. In the park management plan step, 1) classified ecosystem and landscae preservation zone, ecosystem protection zone and ecosystem restoration zone as ecosystem and landscape preservation plan, 2) plannings for ecosystem, fine landscape preservation, damaged area restoration and recovery plan were established in order to suggest environment-friendly plan,

• Maritime Security
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• v.4 no.1
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• pp.83-113
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• 2022

Although China's maritime militia has not been well known despite its long history, it is recently emerging as a serious threat to maritime security, causing neighboring countries' security concerns due to the growing number of maritime disputes with China. In this regard, it is now time to clearly define the true nature of the Chinese maritime militia. A close look at the organization and roles of the Chinese maritime militia reveals that it is an organization that is systematically managed and operated by the Chinese government and the People's Liberation Army of China. Its role is to serve the purpose of "contributing to the protection and expansion of China's marine interests." In addition, the threat factors of the Chinese maritime militia were analyzed by examining the cases of maritime disputes between the Chinese maritime militia and neighboring countries. First, the Chinese maritime militia has implemented the "Gray Zone Strategy." Second, it is a systematic organization supported by the Chinese government and the People's Liberation Army. Third, it is a maritime power that cannot be ignored as the world's largest militia organization. Fourth, it has a strategic flexibility that enables the execution of the dual mission of working for a living such as commercial fishing and serving in the maritime militia. The threats of the Chinese maritime militia are not limited to Southeast Asian countries located in the South China Sea. This is also the case in Korea as the country cannot avoid maritime disputes with China such as the Ieodo issue and the boundary delimitation of the West Sea. Accordingly, this study was focused on presenting a predictable scenario and countermeasures based on the analysis through a scenario technique with respect to the two cases that are most likely to occur in Korea-China relations. Finally, beyond identifying the nature of the Chinese maritime militia, this study takes a further step to share considerations as to how the organization may operate and develop in the future and how we can cope with its moves.