• Environmental Engineering Research
• /
• v.23 no.4
• /
• pp.406-419
• /
• 2018

In planning public service systems such as waterworks, the design population is very important factor. Owing to the limitations of the indirect method, two new models, which take into consideration urban characteristics, were developed to accurately predict external migration rate (EMR), which is an essential component in estimating reliably the design population. The root mean square error (RMSE) between the model values and observed values were 10.12 and 15.58 for the metropolitan cities and counties respectively and were lower compared to RMSE values of 27.31 and 28.79 obtained by the indirect method. Thus, the developed models provide a more accurate estimate of EMR than the indirect method. In addition, the major influencing factors for external migration in counties were development type, ageing index, number of businesses. On the other hand, the major influencing migration factors for cities were project scale, distance to city center, manufacturing size, population growth rate and residential environment. Future medium and long-term studies would be done to identify emerging trends to appropriately inform policy making.

• Journal of Power System Engineering
• /
• v.9 no.1
• /
• pp.64-69
• /
• 2005

In evaluation of electronic reliability on the PCB(Print Circuit Borad),electrochemical migration is one of main test objects. The phenomenon of electrochemical migration occurs in the environment of the hight humidity and the hight temperature under bias through a continuous aqueous electrolyte. In this paper, the generating mechanism of electrochemical migration is investigated by using water drop acceleration test under various waters. The waters used in the water drop test are city water, distilled water and ionic water. It found that the generated velocity of electrochemical migration depended on electrolyte quantity which included in the various waters.

• Proceeding of EDISON Challenge
• /
• 2015.03a
• /
• pp.163-166
• /
• 2015

Intramolecular energy migration in a cyclic porphyrin array is spontaneous transfer of energy from one excited site to another. Since the efficiency of energy migration is inversely proportional to distance, the energy migration is occurred on their adjacent sites more often than distant ones. Therefore, the energy migration in the cyclic porphyrin array is largely dependent on their conformational characters. However, evaluation of conformational information by means of experimental tools is ambiguous since their limited resolution. In this work, we calculate the internal angle and distance distributions of cyclic porphyrin arrays using molecular dynamics simulations to obtain conformational information. To evaluate the angle and distance distributions respect to molecular size, we constructed molecules with n porphyrin dimers (n=1,3,7) in implicit solvent environment. Performing molecular dynamics simulations, we modulated alkyl groups to investigate additional conformational effects of the system.

• Journal of Korean Academy of Nursing
• /
• v.47 no.5
• /
• pp.676-688
• /
• 2017

Purpose: The purpose of this study was to analyze the migration patterns of new nurses and experienced nurses and to identify the factors influencing inter-regional migration for solving regional imbalances of clinical nurses in South Korea. Methods: This study involved a secondary analysis of data from the Health Insurance Review and Assessment Service (HIRA). Data were analyzed using descriptive statistics and multiple logistic regression analysis. Results: New nurses tended to migrate from Kyunggi to Seoul. However, experienced nurses tended to migrate from Seoul and Chungchung to Kyunggi. Significant predictors of inter-regional migration among new nurses were location and nurse staffing grade of hospitals. Significant predictors of inter-regional migration among experienced nurses were location, hospital type, nurse staffing grade, ownership of hospitals and age of nurses. Conclusion: Inter-regional migration occupied a small portion of total hospital movement among clinical nurses. The regional imbalances of nurses were not caused by the migration from non-metropolitan areas to Seoul. Nurse shortage problems in the small and medium hospitals of the non-metropolitan area can be solved only through improvement of work environment.

• Korean Journal of Materials Research
• /
• v.15 no.1
• /
• pp.54-60
• /
• 2005

Recently a lots of problems have observed in high densified and high integrated electronic components. One of them is ion migration phenomena, which induce the electrical short of electrical circuit. ion migration phenomena has been observed in the field of exposing the specific environment and using for a long tin e. This study was evaluated the generation time of ion migration and was investigated properly test method through water drop test and high temperature high humidity test. Also we observed direct causes and confirmed generation mechanism of dendritic growth as we reproduced the ion migration phenomena. We utilized PCB(printed circuit board) having a comb pattern as follows 0.5, 1.0, 2.0 mm pattern distance. Cu, SnPb and Au were electroplated on the comb pattern. 6.5 V and 15 V were applied in the comb pattern and then we measured the electrical short time causing by ion migration. In these results, we examined a difference of ion migration time depending on pattern materials, applied voltage and pattern spacing of PCB conductor.

• Journal of Digital Convergence
• /
• v.12 no.11
• /
• pp.317-327
• /
• 2014

In present company has been developed various systems for work efficiently and organized. However, each work developed Systems Environment differently by rapid IT advancement; it requires a lot of maintenance cost. Recently many companies need to do systems integration or downsizing migration to save costs for IT maintenance, but most of companies are now develop migration with built new systems by manual work or modify some part only. Also migration requires high cost. In this paper, by focusing in application on the environment of the system components, propose the recycling and utilization of automation tools, application method to reduce the migration cost.

• Journal of Ecology and Environment
• /
• v.44 no.4
• /
• pp.207-211
• /
• 2020

Adult land crabs generally live on land while their larvae live in the sea. In the case of Sesarma haematoche, female crabs migrate from land to sea to release the larvae at the high tide of syzygy night. Artificial structures along coastal areas are being obstacles for the migration of land crabs and causing synchronized roadkills on coastal roads during breeding migration. In this research, we compared the sex ratios of crab populations in coastal areas with coastal roads and uninhabited island areas with no road. The proportion of females in inland habitats with coastal roads was significantly smaller than island habitats. In particular, females are exposed to the risk of annually repeated roadkills, and the proportion of females decreases rapidly with their growth. If this tendency is general for land crab populations in the coastal areas with roads, significant road mortality of female land crabs during breeding migration can lead to severe population decline in coastal areas. Therefore, it is necessary to take an action to save land crabs crossing coastal roads.

• Development and Reproduction
• /
• v.27 no.4
• /
• pp.221-226
• /
• 2023

A stem cell niche provides an environment that governs stem cell maintenance and division. Thus, the development of a proper niche is of prime importance to stem cell behaviors. Mechanisms of niche development are beginning to be revealed in the Drosophila male gonad. Niche cells are initially dispersed throughout the gonad, then assemble at its apical tip through the anterior migration of posteriorly located niche cells. The molecular mechanisms of this migration and assembly are still poorly understood. Here we show evidence suggesting that Lin28, an RNA-binding protein and regulator of let7 genesis, might be an intrinsic factor for the anterior migration of niche cells. We found that a dispersed, ectopic niche, a phenotype observed with anterior migration defects, occurs in lin28 mutant gonads. This phenotype is rescued by expression of lin28 in the niche cells. These findings suggest that Lin28 might be required for the anterior migration of niche cells.

• Journal of KIISE:Computing Practices and Letters
• /
• v.7 no.6
• /
• pp.653-660
• /
• 2001

Recently, The range of Internet based information environment is spreading over core business area, as well as simple information provision area. Especially, with spreading WWW technology, markup language based technology is emerging as an important part in Internet based business. But, the data made by SGML can only see by using SGML Browser, so it has some problem in information providing at Internet, and compatibility of data between Data source. So, this study suggests essential architecture and technique for migrating from SGML to XML environment. In our study, we use 600MB SGML data that are selected from 3Tera DataBase of SGML as testing target for migration. We can reduce data displaying time after migration, can do mobile computing which is based on Internet as a result of this study. And the same technique and idea that is used in this study can apply to more large SGML Environment without changing. So, It will be very helpful to the reader who is interesting to migrate from SGML doc to XML doc.

• International Journal of Computer Science & Network Security
• /
• v.24 no.4
• /
• pp.60-66
• /
• 2024

Host's data during transmission. Data tempering results in loss of host's sensitive information, which includes number of VM, storage availability, and other information. In the distributed cloud environment, each server (computing server (CS)) configured with Local Resource Monitors (LRMs) which runs independently and performs Virtual Machine (VM) migrations to nearby servers. Approaches like predictive VM migration [21] [22] by each server considering nearby server's CPU usage, roatative decision making capacity [21] among the servers in distributed cloud environment has been proposed. This approaches usage underlying server's computing power for predicting own server's future resource utilization and nearby server's resource usage computation. It results in running VM and its running application to remain in waiting state for computing power. In order to reduce this, a decentralized decision making hybrid model for VM migration need to be proposed where servers in decentralized cloud receives, future resource usage by analytical computing system and takes decision for migrating VM to its neighbor servers. Host's in the decentralized cloud shares, their detail with peer servers after fixed interval, this results in chance to tempering messages that would be exchanged in between HC and CH. At the same time, it reduces chance of over utilization of peer servers, caused due to compromised host. This paper discusses, an roatative decisive (RD) approach for VM migration among peer computing servers (CS) in decentralized cloud environment, preserving confidentiality and integrity of the host's data. Experimental result shows that, the proposed predictive VM migration approach reduces extra VM migration caused due over utilization of identified servers and reduces number of active servers in greater extent, and ensures confidentiality and integrity of peer host's data.