• Archives of Plastic Surgery
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• v.37 no.4
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• pp.469-472
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• 2010

Purpose: Aplasia Cutis Congenita (ACC) is a rare disease characterized by the focal defect of the skin at birth, frequently involving scalp, but it may affect any region of the body. There are no etiology known but some conditions such as intrauterine vascular ischemia, amniotic adherences and viral infections are associated. The ideal treatment for the ACC is not known. Superficial and relatively small sized defects (< $3{\times}5\;cm$) may heal spontaneously and large defects related with risks of infection and bleeding may require aggressive surgical treatment. Hyalomatrix$^{(R)}$ is a bilayer of an esterified hyaluronan scaffold beneath a silicone membrane. It has been used as a temporary dermal substitute to cover deep thickness skin defect and has physiological functions derive from the structural role in extracellular matrix and interaction with cell surface receptor. This material has been used for the wound bed pre-treatment for skin graft to follow and especially in uncooperative patient, like a newborn, this could be a efficient and aseptic way of promoting granulation without daily irritative wound care. For this reason, using Hyalomatrix$^{(R)}$ for the treatment of ACC was preferred in this paper. Methods: We report a case of a newborn with ACC of the vertex scalp and non-ossified partial skull defect. The large sized skin and skull defect ($6{\times}6\;cm$) was found with intact dura mater. No other complications such as bleeding or abnormal neurologic sign were accompanied. Escharectomy was performed and Hyalomatrix$^{(R)}$ was applied for the protection and the induction of acute wound healing for 3 months before the split-thickness skin graft. During the 3 months period, the dressing was renewed in aseptic technique for every 3 weeks. The skin graft was achieved on the healthy granulation bed. Results: The operative procedure was uneventful without necessity of blood transfusion. Postoperative physical examination revealed no additional abnormalities. Regular wound management was performed in out-patient clinic and the grafted skin was taken completely. No other problems developed during follow-up. Conclusion: Hyalomatrix$^{(R)}$ provides protective and favorable environment for wound healing. The combination of the use of Hyalomatrix$^{(R)}$ and the skin graft will be a good alternative for the ACC patients with relatively large defect on vertex.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.142-151
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• 2020

This study is designed to deduce an implication for an effective implementation of the Special Act for Conservation, Management and Utilization of World Heritage in Korea which was legislated in February, 2020. To draw an implication, which is regarded as highly valuable for preparing for the implementation of the act, several case studies were performed focusing on four World Natural Heritage sites in Japan, and the result is as follows. First, it is enormously crucial for the central administration agencies and the local government to have a system through which they communicate one another regularly. All the target areas in Japan consist of three national parks and a prefectural park with natural monuments, and the national forest covers a tremendously large proportion of the areas. The Japanese central agencies including Ministry of the Environment, Forestry Agency and Agency for Cultural Affairs have communication with the local government through a system named Regional Liaison Committee in order to manage the sites effectively. Also, in the case of Japan, de facto administrating agencies involving non-profit organizations and the tourism association also participate in the regular conferences to communicate. Second, a specific committee consisting of academic advisers is strongly needed. In the case of Japan, Scientific Committee provides academic grounds for the management plan established by the members of Regional Liaison Committee, and an active system which allows the members to organize consultative committees and subcommittees has been established. Scientific Committee plays an important role in preventing the local government, which tends to manage the world natural heritage in more economically profitable ways, from damaging the environment of the site. The establishment of this type of committee is thought to be extremely desirable because the World Natural Heritage requires comprehensive and sustainable management plans on the ecosystem. Third, establishment of comprehensive management plan based on continuous monitoring on the environment and detailed action plan is exceedingly needed. To sum up, it is vital to establish a management plan considering environmental aspect, and detailed guidelines, which help execute the plan both properly and effectively, are required for systematic and sustainable management.

• Progress in Medical Physics
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• v.10 no.2
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• pp.103-114
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• 1999

In this study, as a preliminary study for developing a full 3D photon dose calculation algorithm, We developed 2.5D photon dose calculation algorithm by extending 2D calculation algorithm to allow non-coplanar configurations of photon beams. For this purpose, we defined the 3d patient coordinate system and the 3d beam coordinate system, which are appropriate to 3d treatment planning and dose calculation. and then, calculate a transformation matrix between them. For dose calculation, we extended 2d "Clarkson-Cunningham" model to 3d one, which can calculate wedge fields as well as regular and irregular fields on arbitrary plane. The simple Batho's power-law method was implemented as an inhomogeneity correction. We evaluated the accuracy of our dose model following procedures of AAPM TG#23; radiation treatment planning dosimetry verifications for 4MV of Varian Clinac-4. As results, PDDs (percent depth dose) of cubic fields, the accuracy of calculation are within 1% except buildup region, and $\pm$3% for irregular fields and wedge fields. And for 45$^{\circ}$ oblique incident beam, the deviations between measurements and calculations are within $\pm$4%. In the case of inhomogeneity correction, the calculation underestimate 7% at the lung/water boundary and overestimate 3% at the bone/water boundary. At the conclusions, we found out our model can predict dose with 5% accuracy at the general condition. we expect our model can be used as a tool for educational and research purpose.. purpose..

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.113-121
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• 2004

The present study is suggested to estimate the degree of secondary consolidation caused by various changes of stress such as loading, unloading and reloading in improving poor subsoil through pre-compression loading construction method and, for this purpose, examined the characteristics of the consolidation of Kunsan clay through incremental loading test (IL) using standard consolidation tester and constant loading rate test (CLR), which were adapted from the constant rate of strain test (CRS). In addition, after CRS test, this study determined the characteristics of secondary consolidation and relationships among void ratio, effective stress and time according to the ratio of effective over-consolidation on reloading at the point of time of random expansion. Kunsan clay had larger expansion and smaller secondary consolidation settlement when the ratio of effective over-consolidation was high. In addition, when loading was applied after the load was removed at once, the secondary consolidation coefficient $C'_{\alpha}$ was smaller than that when the load was removed gradually, and when the ratio of effective over-consolidation was over 1.4 a similar value was produced. Based on the entire settlement resulting from reloading, the secondary consolidation coefficient $C"_{\alpha}$ increased non-linearly with the lapse of time but the final value was similar to that in the case of rapid removal. The strain velocity of void ratio was in a regular linear relationship with the increase of loading time regardless of the ratio of effective over-consolidation in both tests and it grew smaller with the increase of the ratio of effective over-consolidation.tion.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.18-18
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• 2011

Climate change is impacting and will increasingly impact both the quantity and quality of the world's water resources in a variety of ways. In some areas warming climate results in increased rainfall, surface runoff, and groundwater recharge while in others there may be declines in all of these. Water quality is described by a number of variables. Some are directly impacted by climate change. Temperature is an obvious example. Notably, increased atmospheric concentrations of $CO_2$ triggering climate change increase the $CO_2$ dissolving into water. This has manifold consequences including decreased pH and increased alkalinity, with resultant increases in dissolved concentrations of the minerals in geologic materials contacted by such water. Climate change is also expected to increase the number and intensity of extreme climate events, with related hydrologic changes. A simple framework has been developed in New Zealand for assessing and predicting climate change impacts on water resources. Assessment is largely based on trend analysis of historic data using the non-parametric Mann-Kendall method. Trend analysis requires long-term, regular monitoring data for both climate and hydrologic variables. Data quality is of primary importance and data gaps must be avoided. Quantitative prediction of climate change impacts on the quantity of water resources can be accomplished by computer modelling. This requires the serial coupling of various models. For example, regional downscaling of results from a world-wide general circulation model (GCM) can be used to forecast temperatures and precipitation for various emissions scenarios in specific catchments. Mechanistic or artificial intelligence modelling can then be used with these inputs to simulate climate change impacts over time, such as changes in streamflow, groundwater-surface water interactions, and changes in groundwater levels. The Waimea Plains catchment in New Zealand was selected for a test application of these assessment and prediction methods. This catchment is predicted to undergo relatively minor impacts due to climate change. All available climate and hydrologic databases were obtained and analyzed. These included climate (temperature, precipitation, solar radiation and sunshine hours, evapotranspiration, humidity, and cloud cover) and hydrologic (streamflow and quality and groundwater levels and quality) records. Results varied but there were indications of atmospheric temperature increasing, rainfall decreasing, streamflow decreasing, and groundwater level decreasing trends. Artificial intelligence modelling was applied to predict water usage, rainfall recharge of groundwater, and upstream flow for two regionally downscaled climate change scenarios (A1B and A2). The AI methods used were multi-layer perceptron (MLP) with extended Kalman filtering (EKF), genetic programming (GP), and a dynamic neuro-fuzzy local modelling system (DNFLMS), respectively. These were then used as inputs to a mechanistic groundwater flow-surface water interaction model (MODFLOW). A DNFLMS was also used to simulate downstream flow and groundwater levels for comparison with MODFLOW outputs. MODFLOW and DNFLMS outputs were consistent. They indicated declines in streamflow on the order of 21 to 23% for MODFLOW and DNFLMS (A1B scenario), respectively, and 27% in both cases for the A2 scenario under severe drought conditions by 2058-2059, with little if any change in groundwater levels.

• Atmosphere
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• v.29 no.5
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• pp.511-523
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• 2019

A new Korean Meteorological Administration (KMA) airborne measurement platform has been established for regular observations for scientific purpose over South Korea since late 2017. CRDS G-2401m analyzer mounted on the King Air 350HW was used to continuous measurement of CO₂, CH₄ and CO mole fraction. The total uncertainty of measurements was estimated to be 0.07 ppm for CO₂, 0.5 ppb for CH₄, and 4.2 ppb for CO by combination of instrument precision, repeatability test simulated in-flight condition and water vapor correction uncertainty. The airborne vertical profile measurements were performed at a regional Global Atmosphere Watch (GAW) Anmyeon-do (AMY) station that belongs to the Total Carbon Column Observing Network (TCCON) and provides concurrent observations to the Greenhouse Gases Observing Satellite (GOSAT) overpasses. The vertical profile of CO₂ shows clear altitude gradient, while the CH₄ shows non-homogenous pattern in the free troposphere over Anmyeon-do. Vertically averaged CO₂ at the altitude between 1.5 and 8.0km are lower than AMY surface background value about 7 ppm but higher than that observed in free troposphere of western pacific region about 4 ppm, respectively. CH₄ shows lower level than those from ground GAW stations, comparable with flask airborne data that was taken in the western pacific region. Furthermore, this study shows that the combination of CH₄ distribution in free troposphere and trajectory analysis, taking account of convective mixing, is a useful tool in investigating CH₄ transport processes from tropical region to Korean region in winter season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.7-12
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• 1994

The kinetics of browning reaction of dried shrimp powder samples were investigated during storage. The temperature conditions of the ding process were $25^{\circ}C\;and\;45^{\circ}C$, and the samples were stored at water activity ($a_w$) of 0.33, 0.44, 0.52, 0.65 and temperatures of $35^{\circ}C,\;45^{\circ}C,\;55^{\circ}C$ and temperature fluctuations between $33^{\circ}C\;and\;55^{\circ}C$. When the shrimp was dried at $25^{\circ}C$ the activation energies obtained from the Arrhenius plot ranged from 13.57 to 14.33 kcal/mol. From these energies of activation, the $Q_{10}$ values at $25^{\circ}C$ showed 1.93 to 2.00. In the case of drying at $45^{\circ}C$ the activation energies were $13.12{\sim}13.61\;kcal/mol$ and $Q_{10}$ values were $1.89{\sim}1.93$, respectively. In addition, a storage study under square-wave fluctuating temperature conditions was carried out by varying the shrimp sample temperature between $35^{\circ}C\;and\;55^{\circ}C$ within 7 days regular fluctuation cycle. The data obtained from the fluctuating temperature storage study will be used in the prediction of shelf-lives. The shelf-lives assessed at $25^{\circ}C$ from the accelerated shelf-life tests ranged from 4 days at aw 0.65 to 139 days at aw 0.33.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.73-76
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• 2009

Purpose: Bone mineral densitometry test region advised by ISCD (International Society for Clinical Densitometry) is both site in case of femur, whereas our medical center measures left femur except for few extraordinary cases. It is said that right-handers had higher mean femur BMD in the left side than in the right side, but the factor influence the femur BMD is unknown. Thus, we investigate whether testing left femur only is a adequate clinical diagnosis. Materials and Methods: Subjects were 209 right-handers and 20 left-handers patient in Asan Medical Center from July to August, 30 to 70 years of age ($51{\pm}6.7$). Subjects fill out the questionnaire on hand preference and taking regular exercise. Total BMDs of bilateral femur were measured with GE Lunar Prodigy advance densitometer, and the statistical soft ware SPSS 12.0 for windows was used for statistical analysis. Results: In the total sample of the exercise group (n=127), the difference of both femur mean BMDs are $0.001{\pm}0.127\;g/cm^2$ and the non-exercise group's (n=102) both femur difference is $0.002{\pm}0.126\;g/cm^2$, there is no significant difference. And in exercise group, classified according to hand preference, each t-value is shown at right handers (n=114) are 0.65, left handers (n=13) are -0.39. Also, In non-exercise group, right handers (n=95) are -0.78, left handers (n=7) are -0.64. In the 95% confidence limit, there was no statistically significant difference (p>0.05). Conclusions: In recently researchs, there have been differences between both femurs according to hand preference. However, Our study have no significant difference both femurs BMDs. Therefore we suggest that BMD measurement of femur has no problem only one side, except for particular case like femur operation.

• Journal of Distribution Science
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• v.10 no.4
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• pp.13-20
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• 2012

The "flextime" system, which was initially designed to maintain a balance between work and personal life, has recently received much attention as an alternative form of work, enabling employees to fully exert their creativity. Most studies show that the effects of flextime on performance, productivity, attitude toward the organization, absenteeism, and turnover differ between managerial and non-managerial workers. This suggests that workers' personal characteristics affect their preference for flextime by directly or indirectly influencing its result variables. As most Korean companies have not adopted the flextime system, little research has been conducted on it in Korea. Recently, Korean companies have been discussing flextime as one of several measures for enhancing international competitiveness. Therefore, this study aims to offer a theoretical framework for the introduction of the system by analyzing the effects of the precedent factors on the preference for flextime. Though not statistically significant, a higher preference for flextime is noted among workers over the age of 36. Older workers usually are more conservative and less adaptable to change but here the older Korean workers may be anxious and resistant. Additional research on workers in different types of businesses using improved research methods will lead to more meaningful results. Married workers display a lower preference to flextime than single workers. In Korea, the current atmosphere focused on a happy home encourages married workers to prefer regular work hours, enabling them to go to and from work on a regular schedule. This means that normal working hours, from morning to evening, are preferred as it is the most suitable system for families. However, this is not so in the case of single workers. Unmarried singles tend to prefer flextime for investing in self-development toward future prosperity, over the benefits of regular working-hours. Flextime is designed to meet their needs to some extent as it is helpful in maintaining a balance between work life and self-development. If flextime is selected, workers can spend mornings on self-development and work in the afternoons. Therefore, when flextime is introduced in Korea, it would be desirable to start with unmarried workers, to increase corporate creativity and productivity and develop individual potential. In particular, when the five-day workweek, the main concern for companies and labor unions, is adopted, synergy with flextime could be expected and a gradual implementation of flextime will be effective. Gender difference shows similar results to marital status with male workers displaying a higher preference for flextime. It is inferred that male workers' attitudes toward flextime are more favorable than female workers' because flextime enables self-development and work life to coexist. A relatively weak, though statistically significant, correlation exists between control position and flextime preference with inner-control-oriented workers displaying favorable attitudes toward flextime. Generally, inner-control-oriented workers tend to attribute the consequences caused by any person or partner relationship to themselves. Thus, when a new system is introduced they are likely to have less reluctance and fear than outer-control-oriented workers, because they think it is important to deal with the new system. A weak but slight correlation exists between the desire for achievement and flextime preference. People who have a higher desire for achievement are willing to consider the new system, especially if significant success is reasonably expected. This result is derived from a reasonable judgment that flextime offers an individual the time for self-development while the organization benefits from the resulting creativity and performance enhancements. Although not the primary analysis, a high correlation is found between control position and the desire for achievement, which is consistent with the results of previous research. The regression analysis not only supports the preceding ANOVA and correlation analysis but also shows the existence of a causal relationship. Married workers have a weak preference for flextime, which is consistent with the results of the preceding ANOVA. Relative to men, women have a weak preference for flextime. No statistically significant correlation was noticed for age. Inner-control-oriented workers prefer flextime more than outer-control-oriented workers as the former view the consequences of change to be their own responsibility. However, the preference for flextime seems to be weak. As expected, people with a higher desire for achievement have a stronger preference for flextime, presumably because the greater the desire for achievement, the stronger the spirit of challenging an uncertain future. No significant correlation exists between job satisfaction and flextime preference.

• Journal of Sericultural and Entomological Science
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• v.21 no.2
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• pp.11-19
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• 1979

This has been carried out how the sericin insoluble fixations of raw silk should be with potassium alum. This is learned from the leather tanning technique which the process works with collagen, a kind of proteins. Former reports had shown such works, however, they did not consider the moisture absorbability after their process reports by using chromium alum, formalin or vinyl acetate grafting. This report, however, paid attention to protect such absorbability as well as sericin fixation, so far it may be useful for plactical use of silk. In order to clear how the sericin is fixed with such chemicals, fundermental mechanism of weding process and chemical reaction against proteins were also discussed. The obtained results of the report are as followings. 1. Alum should not be treated for raw silk with high temperature bath like other reports because such treat induces raw silk to be stiffly after the treat. 2. It is recommended that raw silk should be treated with alum solution at room temperature for more than three hours. Even in this case, the use of only alum with raw silk could to fix sericin some how, but it increased the water proofness of the silk. 3. 1% of alum solution was found to be able to fix the sericin of raw silk. 4. In case we consider only sericin fixations, a combination treat of 1% alum for three hours and 0.5% NaOH for ten minutes method showed the best result. 5. In case we consider sericin insoluble fixation and moisture absorbility, the reversive combination of the above process was found to be the best results. 6. Sericin fixing evidence was shown with drying feature curves of wed each treated silk where we could to analyze how the chemical nature is changed after each treat. 7. Deguming ratio may be obtained up to 4.3% after the alum combination treat with regular raw silk. Such ratio was considered to be good enough for the purpose when the textile is washed with warm soap water. 8. Moisture absorbability of the combination treat of alum and NaOH was found to be good enough as well as non treated silk. 9. The tenacity and elongation of the treated silk did not change even after three month. 10. Above all, this method is considered to be better process than other coloured fixing (tannin method. Cr-alum method) or smell fixing (formalin method. vinyl acetate method).