• Korean Journal of Materials Research
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• v.29 no.7
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• pp.456-462
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• 2019

ZnO thin-films are grown on a p-Si(111) substrate by RF sputtering. The effects of growth temperature and $O_2$ mixture ratio on the ZnO films are investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and room-temperature photoluminescence (PL) measurements. All the grown ZnO thin films show a strong preferred orientation along the c-axis, with an intense ultraviolet emission centered at 377 nm. However, when $O_2$ is mixed with the sputtering gas, the half width at half maximum (FWHM) of the XRD peak increases and the deep-level defect-related emission PL band becomes pronounced. In addition, an n-ZnO/p-Si heterojunction diode is fabricated by photolithographic processes and characterized using its current-voltage (I-V) characteristic curve and photoresponsivity. The fabricated n-ZnO/p-Si heterojunction diode exhibits typical rectifying I-V characteristics, with turn-on voltage of about 1.1 V and ideality factor of 1.7. The ratio of current density at ${\pm}3V$ of the reverse and forward bias voltage is about $5.8{\times}10^3$, which demonstrates the switching performance of the fabricated diode. The photoresponse of the diode under illumination of chopped with 40 Hz white light source shows fast response time and recovery time of 0.5 msec and 0.4 msec, respectively.

• Journal of Climate Change Research
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• v.7 no.3
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• pp.237-247
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• 2016

Global warming caused by greenhouse gases is one of the foremost challenges in the international community. As an alternative to solve this problem, the importance of CCS (Carbon Capture and Storage) technology is increasing. However, due to the delay of European financial crisis recovery, some large-scale CCS projects were postponed. In turn, large-scale CCS projects in South Korea have not been launched as originally planned. Given these situations, it is important to review the latest R&D activities related to CCS in South Korea, and then adjust relevant national policy accordingly. The purpose of this study is to identify policy issues for the effective promotion of CCS technology in South Korea. Following the analysis of recent global trend on CCS policy, we evaluated the results and achievements from national CCS projects, which had been listed under the "Korean National CCS Master Action Plan (2010)". Especially, we tried to review the attainability for the original goal of each project. Through the present study, we identified the current status of CCS technology in South Korea and suggested efficient ways to be taken in order to increase efficiency in implementing national CCS policy in the future.

• International journal of advanced smart convergence
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• v.12 no.4
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• pp.208-216
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• 2023

The purpose of our study is to design datasets for Artificial Intelligence learning for cold sea fish farming. Salmon is considered one of the most popular fish species among men and women of all ages, but most supplies depend on imports. Recently, salmon farming, which is rapidly emerging as a specialized industry in Gangwon-do, has attracted attention. Therefore, in order to successfully develop salmon farming, the need to systematically build data related to salmon and salmon farming and use it to develop aquaculture techniques is raised. Meanwhile, the catch of pollack continues to decrease. Efforts should be made to improve the major factors affecting pollack survival based on data, as well as increasing the discharge volume for resource recovery. To this end, it is necessary to systematically collect and analyze data related to pollack catch and ecology to prepare a sustainable resource management strategy. Image data was obtained using CCTV and underwater cameras to establish an intelligent aquaculture strategy for salmon and pollock, which are considered representative fish species in Gangwon-do. Using these data, we built learning data suitable for AI analysis and prediction. Such data construction can be used to develop models for predicting the growth of salmon and pollack, and to develop algorithms for AI services that can predict water temperature, one of the key variables that determine the survival rate of pollack. This in turn will enable intelligent aquaculture and resource management taking into account the ecological characteristics of fish species. These studies look forward to achievements on an important level for sustainable fisheries and fisheries resource management.

• Journal of Climate Change Research
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• v.4 no.1
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• pp.51-61
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• 2013

To address the problems associated with climate change and energy shortage, Korea has been making efforts to turn waste materials into usable energy. Due to the ongoing efforts to convert waste materials into energy, waste incineration is expanding to utilize the heat generated, and the subsequent greenhouse gas emissions from these waste material incineration are expected to increase. In this study, a municipal waste incineration plant that generates heat and electricity through heat recovery was selected as a subject facility. Methods for estimating the greenhouse gas emissions in the municipal waste incineration plant that was selected as a subject plant were sought, and the greenhouse gas emissions and emission factor were estimated. The $CO_2$ concentrations in discharge gas from the subject facility were on average 6.99%, and the result from calculating this into greenhouse gas emissions showed that the total amount of emissions was $254.60ton\;CO_2/day$. The net emissions, excluding the amount of greenhouse gas emitted from biomass incineration, was shown to be $110.59ton\;CO_2/day$. In addition, after estimating the emissions by separating the heat and electricity generated in the incineration facility, greenhouse gas emission factors were calculated using the greenhouse gas emissions produced per each unit of output. The estimated emission factor for heat was found to be $0.047ton\;CO_2/GJ$ and the emission factor for electricity was found to be $0.652ton\;CO_2/MWh$. The estimated emission factor was shown to be about 17% lower than the $0.783ton\;CO_2/MWh$ emission factor for thermal power plants that use fossil fuels. Waste material types and fossil carbon contents were evaluated as being the factors that have major effects on the greenhouse gas emissions and emission factor.

• Journal of Korean Academy of Nursing
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• v.3 no.1
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• pp.85-95
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• 1972

For the purpose to clarify the effects of nursing, intervention with comfort measures which promote rest, exercise and sleep on the patient′s rehabilitation, this study was carried out on 119 postoperative patients at St. Mary′s Hospital, the National Medical Center and Seoul Red Cross Hospital during the 9 months period from March 1971 to November 1971. In this study one experimental nursing approach was utilized; an emphasis on interpersonal techniques along with physical care-comfort measures. A daily evening care including support and instruction was given to facilitate interaction of nursing to the experimental group by the investigator. For the control group, routine hospital nursing care was performed. The nursing observation was followed for 4 days postoperatively and recorded in check list. The results of the findings were as follows. 1. 3.5% of control group and 32.3% of experimental group got out of bed within 24 hours postoperatively. 38.6% of control group got out of bed within 72 hours postoperatively where only 16.1% of the experimental group did (x$^2$= 19.865, p<0.005). Interaction in nursing is, in turn, significantly more effective than the usual routine care in improving rate of healing. 2. The irritations and tension that may interfere patient′s sleep and rest at night can be reduced to a minimum if nursing environment is better controlled with planned nursing care for individual patient. Various treatments which tend to give patient discomfort may preferably be performed before 6 p.m. if not absolutely indicated. 3. During 4 days of observation the patients without administration of sedatives and analgesics postoperatively were 25.9% in the experimental group where as 10.5% in the control group. The frequency of administration of sedatives and analgesics in average was 1.4 in the experimental group, and 2.0 in the control group. This indicates that not all postoperative discomforts expressed by the patients should be regarded as incision pain, and those discomforts could be relieved to a certain extent by nursing interventions effectively. 4. There were significant differences between the responses to nursing care given in the experimental group and 33% of the control group in average through 4 days of observation responded "good". 3.6% of the experimental group and 17. 1% of the control group responded "poor" in this study. It was recommended that the study be replicated in a more defined and controlled manner. Some alternative areas for investigation were suggested.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.690-698
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• 2010

Contamination of groundwater resources by organic chemicals has become an issue of increasing environmental concern. Surfactant-enhanced aquifer remediation (SEAR) is widely recognized as one of the most promising techniques to remediate organic contaminations in-situ. Solutions of surfactant or surfactant with polymer are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In the design of surfactant-based technologies for remediation of organic contaminated aquifers, it is very important to have a considerable analysis using extensive numerical simulations prior to full-scale implementation. This study investigated the formation and flow of microemulsions during SEAR of organic-contaminated aquifer using the finite difference model UTCHEM, a three-dimensional, multicomponent, multiphase, compositional model. The remediation process variables considered in this study were the sequence of injection fluids, the injection and extraction rate, the concentrations of polymer in surfactant slug and chase water, and the duration of surfactant injection. For each variable, temporal changes in injection and production wells and spatial distributions of relative saturations in the organic phase were compared. Cleanup time and cumulative organic recovery were also quantified. The study would provide useful information to design strategies for the remediation of nonaqueous phase liquid-contaminated aquifers.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.259-265
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• 1998

A field experiment was conducted to investigate changes of $NH_4-N$, N uptake, N use efficiency and rice yield by the Latex coated urea(LCU) application on wet-seeding rice from 1994 to 1997. Nitrogen deficiency symptom appeared when LCU was applied as basal dressing continuously until the ripening stage during normal temperature year, but was completed at heading stage during year at high temperature. Percentage recovery of fertilizer N was higher in LCU than in urea but decreased in high temperature. Turn over of N applied as LCU to grain increased more during years high temperature than the normal year. Rice yield with LCU treatment compared to conventional treatment was similar during the normal year but decreased by 6% during year of high temperature. Top dressing of urea at panicle initiation stage in addition to basal dressing of LCU increased rice yield to 12%.

• Journal of Korean Academy of Nursing
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• v.24 no.1
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• pp.47-57
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• 1994

The purpose of this study was to examine nurses’ perceptions of medication treatment for psychiatric patients and to compare these perceptions with the perceptions held by the patients. The methodology used in this study was a descriptive design with semi-structured and open-ended interviews. This study used a convenience sample of 112 nurses who worked in, and 209 patients who were under psychiatric treatment, in four hospitals attached to a university and one national mental hospital in the city of Seoul. The collected data were analyzed by SAS, using percentages for descriptive purposes, and t-test or x$^2$ for comparing the variables. The results were as follows : 1. There was no significant differences between nurses’ and patients’ perceptions on the extent to which patients complied with their medication treatment. Generally speaking, the mean compliance scores for both nurses and patients was high(nurse : (equation omitted)=3.70, Patient : (equation omitted)=3.76). 2. There was a significant difference in nurses’ and patients’ perceptions on the reasons why patients do not take medication. The nurse group indicated that the patients did not take medication because of the “worry about side effects or habituation(49.53%)”, “boredom from long-term use of medication(26.17%)” and “distrust toward medical staff(12.15% )”, but the patient group indicated that they “did not want to be dependent on medication (25%)”, “forgot to take medication(19.7%) and “worried about side effects or habituation(15.91%). 3. As for the necessity of medication, both groups showed some different responses. Even though both groups were aware of the necessity of taking medication, the patient group(21.53%) showed a more negative response. As (or the effects of medication, both groups (nurses and patients ) showed positive responses. However, the nurse group showed a higher positive response (91.07% ) than the patient group(74.16%), 5. Both the patient and nurse group indicated that the most helpful element for the patient’s life under psychiatric treatment was interviews and conversations with therapists and nurses. However, the nurse group showed a higher response(70.15%) than the patients group(47.15%). According to the patient group, family support for the patient was another important factor for psychiatric treatment and daily struggles. In conclusion, as there were differences between the perception of nurses and patients, the nurse must consider the patients’ subjective perceptions first. They should also revaluate their false belief and prejudice concerning the patients’ perceptions. Such information can provide a base to be applied by the nurses in devloping effective mutual relationships with patients which can in turn help in compliance with medication regimen. As it was confirmed that medication was the most important factor in the patients’ recovery, a thorough education program on the therapeutic effect of medication and the necessity of their continued use after discharge is also needed.

• Journal of Platform Technology
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• v.9 no.1
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• pp.15-22
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• 2021

In a smart manufacturing environment, more and more devices are connected to the Internet so that a large volume of data can be obtained during all phases of the product life cycle. The large-scale industries, companies and organizations that have more operational units scattered among the various geographical locations face a huge resource consumption because of their unorganized structure of sharing resources among themselves that directly affects the supply chain of the corresponding concerns. Cloud-based smart manufacturing paradigm facilitates a new variety of applications and services to analyze a large volume of data and enable large-scale manufacturing collaboration. The manufacturing units include machinery that may be situated in different geological areas and process instances that are executed from different machinery data should be constantly managed by the super admin to coordinate the manufacturing process in the large-scale industries these environments make the manufacturing process a tedious work to maintain the efficiency of the production unit. The data from all these instances should be monitored to maintain the integrity of the manufacturing service system, all these data are computed in the cloud environment which leads to the latency in the performance of the smart manufacturing service system. Instead, validating data from the external device, we propose to validate the data at the front-end of each device. The validation process can be automated by script validation and then the processed data will be sent to the cloud processing and storing unit. Along with the end-device data validation we will implement the APM(Asset Performance Management) to enhance the productive functionality of the manufacturers. The manufacturing service system will be chunked into modules based on the functionalities of the machines and process instances corresponding to the time schedules of the respective machines. On breaking the whole system into chunks of modules and further divisions as required we can reduce the data loss or data mismatch due to the processing of data from the instances that may be down for maintenance or malfunction ties of the machinery. This will help the admin to trace the individual domains of the smart manufacturing service system that needs attention for error recovery among the various process instances from different machines that operate on the various conditions. This helps in reducing the latency, which in turn increases the efficiency of the whole system

• Molecules and Cells
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• v.45 no.10
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• pp.718-728
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• 2022

Splicing factor B subunit 4 (SF3B4), a component of the U2-pre-mRNA spliceosomal complex, contributes to tumorigenesis in several types of tumors. However, the oncogenic potential of SF3B4 in lung cancer has not yet been determined. The in vivo expression profiles of SF3B4 in non-small cell lung cancer (NSCLC) from publicly available data revealed a significant increase in SF3B4 expression in tumor tissues compared to that in normal tissues. The impact of SF3B4 deletion on the growth of NSCLC cells was determined using a siRNA strategy in A549 lung adenocarcinoma cells. SF3B4 silencing resulted in marked retardation of the A549 cell proliferation, accompanied by the accumulation of cells at the G0/G1 phase and increased expression of p27, p21, and p53. Double knockdown of SF3B4 and p53 resulted in the restoration of p21 expression and partial recovery of cell proliferation, indicating that the p53/p21 axis is involved, at least in part, in the SF3B4-mediated regulation of A549 cell proliferation. We also provided ubiquitination factor E4B (UBE4B) is essential for p53 accumulation after SF3B4 depletion based on followings. First, co-immunoprecipitation showed that SF3B4 interacts with UBE4B. Furthermore, UBE4B levels were decreased by SF3B4 depletion. UBE4B depletion, in turn, reproduced the outcome of SF3B4 depletion, including reduction of polyubiquitinated p53 levels, subsequent induction of p53/p21 and p27, and proliferation retardation. Collectively, our findings indicate the important role of SF3B4 in the regulation of A549 cell proliferation through the UBE4B/p53/p21 axis and p27, implicating the therapeutic strategies for NSCLC targeting SF3B4 and UBE4B.