• Journal of Powder Materials
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• v.29 no.6
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• pp.459-467
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• 2022

Soft magnetic powder materials are used throughout industries such as motors and power converters. When manufacturing Fe-based soft magnetic composites, the size and shape of the soft magnetic powder and the microstructure in the powder are closely related to the magnetic properties. In this study, Fe-Si-Al-P alloy powders were manufactured using various manufacturing process parameter sets, and the process parameters of the vacuum induction melt gas atomization process were set as melt temperature, atomization gas pressure, and gas flow rate. Process variable data that records are converted into 6 types of data for each powder recovery section. Process variable data that recorded minute changes were converted into 6 types of data and used as input variables. As output variables, a total of 6 types were designated by measuring the particle size, flowability, apparent density, and sphericity of the manufactured powders according to the process variable conditions. The sensitivity of the input and output variables was analyzed through the Pearson correlation coefficient, and a total of 6 powder characteristics were analyzed by artificial neural network model. The prediction results were compared with the results through linear regression analysis and response surface methodology, respectively.

• Asia-Pacific Journal of Business
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• v.13 no.4
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• pp.151-161
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• 2022

Purpose - The purpose of this study is to redefine imperial cultural properties and pass on and provide the elegant value of imperial cultural properties with the Allen Collection's promotion to retrieve imperial cultural properties. Design/methodology/approach - This study was approached to deal with the essential interpretation of cultural improvement through discussion in the cultural science approach Findings - As a result of examining ways to revitalize tourism resources using Allen Collection, it is necessary to cultivate international manners and knowledge levels in strengthening imperial awareness through the establishment of imperial museums, enacting laws on standards for designation of imperial cultural assets, and promoting them. In addition, policy needs such as the development plan of the imperial cultural festival, re-establishment, application, reuse, re-establishment, and reproduction according to environmental changes, and technical support and monitoring systems for investigating and preserving imperial cultural assets are needed. Research implications or Originality - The study on the device imperial cultural assets as tour resources the cultural assets mate be not only preserved and inherited to the descendant but also useful in contemporary national emotion positively. for we could obtain wide national support and co-operation in the protection work of cultural assets. What makes our cultural assets leaved indifferent before destruction like this most of all, it is form indifference of the people, we must make an effort to meet with recognizing the value of useful cultural assets by mean of utilizing cultural assets as tour resources to inhibit more damage of destruction of cultural assets.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1759-1772
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• 2023

Chinese named entity recognition (NER) is a challenging work that seeks to find, recognize and classify various types of information elements in unstructured text. Due to the Chinese text has no natural boundary like the spaces in the English text, Chinese named entity identification is much more difficult. At present, most deep learning based NER models are developed using a bidirectional long short-term memory network (BiLSTM), yet the performance still has some space to improve. To further improve their performance in Chinese NER tasks, we propose a new NER model, IDCNN-BiLSTM-Highway, which is a combination of the BiLSTM, the iterated dilated convolutional neural network (IDCNN) and the highway network. In our model, IDCNN is used to achieve multiscale context aggregation from a long sequence of words. Highway network is used to effectively connect different layers of networks, allowing information to pass through network layers smoothly without attenuation. Finally, the global optimum tag result is obtained by introducing conditional random field (CRF). The experimental results show that compared with other popular deep learning-based NER models, our model shows superior performance on two Chinese NER data sets: Resume and Yidu-S4k, The F1-scores are 94.98 and 77.59, respectively.

• Clinical Endoscopy
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• v.56 no.2
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• pp.194-202
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• 2023

Background/Aims: Endoscopic therapy for neoplastic Barrett's esophagus (BE) has become the standard of care over the past two decades. In clinical practice, we regularly encounter patients who fail to achieve complete squamous epithelialization of the esophagus. Although the therapeutic strategies in the individual stages of BE, dysplasia, and esophageal adenocarcinoma are well studied and largely standardized, the problem of inadequate healing after endoscopic therapy is only marginally considered. This study aimed to shed light on the variables influencing inadequate wound healing after endoscopic therapy and the effect of bile acid sequestrants (BAS) on healing. Methods: Retrospective analysis of endoscopically treated neoplastic BE in a single referral center. Results: In 12.1% out of 627 patients, insufficient healing was present 8 to 12 weeks after previous endoscopic therapy. The average follow-up duration was 38.8±18.4 months. Complete healing was achieved in 13 patients already after intensifying proton pump inhibitor therapy. Out of 48 patients under BAS, 29 patients (60.4%) showed complete healing. An additional eight patients (16.7%) improved, but only partial healing was achieved. Eleven (22.9%) patients showed no response to BAS augmented therapy. Conclusions: In cases of insufficient healing even under exhaustion of proton pump inhibitors, treatment with BAS can be an option as an ultimate healing attempt.

• Advances in materials Research
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• v.13 no.3
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• pp.183-194
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• 2024

D3 tools steel and 440C stainless steel (SS) are normally being employed for application such as knife blade and cutting tools. These steels are iron alloys which have high carbon and high chromium content. In this study, lab work focused on the microstructural and corrosion behavior of D3 tools steel and 440C SS after went through heat treatment processes. Heat treatments for both steels were started with normalizing at 1020 ℃, continue with hardening at 1000 ℃followed by oil quenching. Cryogenic treatment was carried out in liquid nitrogen for 24 hours. The addition of cryogenic heat treatment is believed to increase the hardness and corrosion resistance for steels. Both samples were then tempered at two different tempering temperatures, 160 ℃ and 426 ℃. For corrosion test, the samples were immersed in NaCl solution for 30 days to study the corrosion behavior of D3 tool steel and 440C SS after heat treatment. The mechanical properties of these steels have been investigated using Rockwell hardness machine before heat treatment, after heat treatment (before corrosion) and after corrosion test. Microstructure observation of samples was carried out by scanning electron microscopy. The corrosion rate of these steels was calculated after the corrosion test completed. From the results, the highest hardness is observed for D3 tool steel which tempered at 160 ℃(54.1 HRC). In terms of microstructural analysis, primary carbide and pearlite in the as-received samples transform to tempered martensite and cementite after heat treatment process. From this research, for corrosion test, heat treated 440C SS sample tempered with 426 ℃possessed the excellent corrosion resistance with corrosion rate 0.2808 mm/year.

• Journal of Radiation Protection and Research
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• v.21 no.4
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• pp.273-284
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• 1996

Embryos and fetuses are more sensitive to various environmental agents than are adults or children. The biological effects such as intrauterine death and malformation are closely connected with prenatal exposure very various agents. The sensitivity of these embryonic/fetal effects depends on the stage of pregnancy. From the viewpoint of fetal development, embryonic and fetal stages can be divided into three stages : Preimplantation, organogenetic and fetal. Each stage corresponds to 0 to 4.5days, 4.5 to 13.5days, and 13.5days of gestation in mice, respectively. Many studies on the biologcal effects of mice irradiated by ${\gamma}-rays$ at various stages during organogenesis and fetal period have been performed. Based on these results, the dose-effect and dose-response relationships in malformations, intrauterine death, or retardation of the physical growth have been practically modeled by the ICRP(International Commission on Radiological Protection) and other international bodies for radiation protection. Many experimental studies on mice have made it clear that mice embryos in the preimplantation period have a higher sensitivity to radiation for lethal effects than the embryos/fetuses on other prenatal periods. However, no eratogenic effects of radiation at preimplantation stages of mice have been described in many textbooks. It has been believed that 'all or none action results' for radiation of mice during the preimplantation period were applied. The teratogenic and lethal effects during the preimplantation stage are one of the most important problems from the viewpoint of radiological protection, since the preimplantation stage is the period when the pregnancy itself is not noticed by a pregnant woman. There are many physical or chemical agents which affect embryos/fetuses in the environment. It is assumed that each agents indirectly effects a human. Then, a safety criterion on each agent is determined independently. The pregnant ICR mice on 2, 48, 72 or 96 hours post-conception (hpc), at which are preimplantation stage of embryos, were irradiated whole body Cesium-gamma radiation at doses of 0.1, 0.25, 0.5, 1.5, and 2.5 Gy with dose rate of 0.2 Gy/min. In the embryos from the fetuses from the mice irradiated at various period in preimplantation, embryonic/fetal mortalities, incidence of external gross malformation, fetal body weight and sex ratio were observed at day 18 of gestation. The sensitivity of embryonic mortalities in the mice irradiated at the stage of preimplantation were higher than those in the mice irradiated at the stage of organogenesis. And the more sensitive periods of preimplantation stage for embryonic death were 2 and 48 hpc, at which embryos were one cell and 4 to 7 cell stage, respectively. Many types of the external gross malformations such as exencephaly, cleft palate and anophthalmia were observed in the fetuses from the mice irradiated at 2, 72 and 96 hpc. However, no malformations were observed in the mice irradiated at 48 hpc, at which stage the embryos were about 6 cell stage precompacted embryos. So far, it is believed that the embryos on preimplantation stage are not susceptible to teratogens such as radiation and chemical agents. In this study, the sensitivity for external malformations in the fetuses from the mice irradiated at preimplantation were higher than those in the fetuses on stage of organogenesis.

• Journal of dental hygiene science
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• v.9 no.3
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• pp.339-344
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• 2009

The purpose of this study was to examine the knowledge of some adults about oral hygiene devices and their use of the oral hygiene devices. After a survey was conducted from December 3 to 17,2007, the answer sheets from 352 respondents were gathered. and the collected data were analyzed with a SPSS Ver. 17.0 program. The findings of the study were as follows. 1. Concerning the level of knowledge, the adults investigated knew the best that a toothbrush should be kept by making the head upward (76.77). On the other hand, they had little knowledge on water pick, tongue cleaner and interdental brush. 2. As for the level of use, they scored highest on keeping their toothbrushes by making the head upward(76.77), In contrast, they scarcely put water pick, electronic toothbrushes, tongue cleaner to use. 3. Knowledge impact of general characteristics involving mate(62.54). 50s over(66.28) and up, four family members(61.54), graduate school graduate(66.78), self-employed and, professionals(63.63), income of 1 to 1.5 million won(66.66), fathers were smokers(51.89) got the highest marks with a mean. 4. Use impact of the general characteristics female(47.70), 40s over 49s under(47.78), four family members(48.18), graduate school graduate(50.17), professionals(49.79), income of 1 to 1.5 million won(51.89), fathers were smokers(48.10) got the highest marks with a mean.

• Journal of Environmental Health Sciences
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• v.46 no.4
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• pp.433-443
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• 2020

Objective: This study aimed to introduce the use of humidifier disinfectant (HD) in hospitals based on an on-site investigation. Methods: A preliminary survey and on-site investigation of HD use were conducted in 23 hospitals. Among them, one hospital without previous information on HD use was selected for a pilot investigation; 22 hospitals were selected based on previous documents and exposure statements from parliamentary investigation and exposure assessment regarding HD. Descriptive statistics were used to present distribution and characteristics of HD purchase and HD use in hospitals. Also, details on interviews from the on-site investigation were described. Results: Among the 23 hospitals, a total of ten were confirmed to have purchased and used an HD (nine hospitals) or HD-like product (one hospital). For the purchased HD products, four hospitals reported 'Aekyung Gaseupgi Mate', two hospitals reported 'Oxy Ssakssak New Gaseupgi Dangbun', and one hospital reported 'Homeplus Gaseupgi Chungjungje' (one hospital used three kinds of HD products). One hospital reported an HD-like product and four hospitals were 'Unknown'. For the number of HD products purchased, five hospitals reported '100 or less', two hospitals reported 'More than 100', and three hospitals were 'Unknown'. For each of the ten hospitals, we described detailed characteristics of HD purchase and its exposure status obtained through on-site investigation, including the purchase volume (i.e., number of products), exposure space (i.e., patient's room, staff space), and exposure period. Additionally, a comparison of on-site investigation and parliamentary investigation or exposure assessment regarding HD was reported. Conclusion: This study introduced detailed cases of HD purchase and HD use in hospitals based on an on-site investigation, and our findings revealed a possibility of a considerable volume of HD exposure in various multiuse facilities, including hospitals.

• Genomics & Informatics
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• v.10 no.1
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• pp.1-8
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• 2012

Recently, the technologies of DNA sequence variation and gene expression profiling have been used widely as approaches in the expertise of genome biology and genetics. The application to genome study has been particularly developed with the introduction of the nextgeneration DNA sequencer (NGS) Roche/454 and Illumina/ Solexa systems, along with bioinformation analysis technologies of whole-genome $de$ $novo$ assembly, expression profiling, DNA variation discovery, and genotyping. Both massive whole-genome shotgun paired-end sequencing and mate paired-end sequencing data are important steps for constructing $de$ $novo$ assembly of novel genome sequencing data. It is necessary to have DNA sequence information from a multiplatform NGS with at least $2{\times}$ and $30{\times}$ depth sequence of genome coverage using Roche/454 and Illumina/Solexa, respectively, for effective an way of de novo assembly. Massive shortlength reading data from the Illumina/Solexa system is enough to discover DNA variation, resulting in reducing the cost of DNA sequencing. Whole-genome expression profile data are useful to approach genome system biology with quantification of expressed RNAs from a wholegenome transcriptome, depending on the tissue samples. The hybrid mRNA sequences from Rohce/454 and Illumina/Solexa are more powerful to find novel genes through $de$ $novo$ assembly in any whole-genome sequenced species. The $20{\times}$ and $50{\times}$ coverage of the estimated transcriptome sequences using Roche/454 and Illumina/Solexa, respectively, is effective to create novel expressed reference sequences. However, only an average $30{\times}$ coverage of a transcriptome with short read sequences of Illumina/Solexa is enough to check expression quantification, compared to the reference expressed sequence tag sequence.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.2
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• pp.146-156
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• 2001

The purpose of this study was twofold. One was to evaluate the wettability of 4 elastomeric impression materials on tooth and different kinds of filling materials. The other was to identify the effect of topical surfactants sprayed on the surface of each impression. The elastomeric impression mate rials used in this experimental study were one polyether(Impregum F) and three polyvinyl siloxanes(Provil novo, Zerosil, Imprint). The abutments were prepared for 3/4 crown or onlay on the extracted human first molar. The filling materials used in this study for the duplication of prepared abutment were composite resin, amalgam, and casting metal. Impression was taken by manufacturer's recommendations and the number of voids on the impression surface was counted. The topical surfactants were Spannex $II^{(R)}$ and $Cohere^{(R)}$. The wettability was evaluated by comparing the number of voids between non-treated group and treated groups. The results were as follows : 1. $Zerosil^{(R)}$ showed the least number of voids on the impression surface. The number of voids increased in order of Provil $novo^{(R)}$, Impregum $F^{(R)}$, and $Imprint^{(R)}$. 2. Impregum $F^{(R)}$ and $Zerosil^{(R)}$ showed the least number of voids on the surface of dental stone master cast. The number is inclosed in order of Provil $novo^{(R)}$ and Imprint 3. When abutment material is tooth, the number of voids on the surface of master cast was smallest compared with that of other abutment materials. The number of voids increased in order of casting metal, amalgam and composite resin 4. The number of voids on the surface of the dental stone master cast was smallest when Spannex $II^{(R)}$ was used, followed by $Cohere^{(R)}$ treated group and non-treated group. These results suggest that the difference in wettability caused by the types of rubber base impression materials as well as abutment materials can affect the number of voids. And the use of topical surfactant for rubber base impression materials can improve the wettability of the materials and enhance the accurate master cast which has fewer surface voids.