• Title/Summary/Keyword: Current limitation effect

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Effect of Nitrogen, Titanium, and Yttrium Doping on High-K Materials as Charge Storage Layer

  • Cui, Ziyang;Xin, Dongxu;Park, Jinsu;Kim, Jaemin;Agrawal, Khushabu;Cho, Eun-Chel;Yi, Junsin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.6
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    • pp.445-449
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    • 2020
  • Non-volatile memory is approaching its fundamental limits with the Si3N4 storage layer, necessitating the use of alternative materials to achieve a higher programming/erasing speed, larger storage window, and better data retention at lower operating voltage. This limitation has restricted the development of the charge-trap memory, but can be addressed by using high-k dielectrics. The paper reviews the doping of nitrogen, titanium, and yttrium on high-k dielectrics as a storage layer by comparing MONOS devices with different storage layers. The results show that nitrogen doping increases the storage window of the Gd2O3 storage layer and improves its charge retention. Titanium doping can increase the charge capture rate of HfO2 storage layer. Yttrium doping increases the storage window of the BaTiO3 storage layer and improves its fatigue characteristics. Parameters such as the dielectric constant, leakage current, and speed of the memory device can be controlled by maintaining a suitable amount of external impurities in the device.

A Structural Relation of professional leadership, environmental competitiveness, market orientation and fundraising effectiveness in social service organizations (사회복지조직의 자원동원성과에 영향을 미치는 요인의 구조적 관계 -리더의 전문적 태도, 환경에 대한 인식, 그리고 시장지향성간의 관계-)

  • Rho, Yeon-hee
    • Korean Journal of Social Welfare Studies
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    • no.37
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    • pp.91-116
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    • 2008
  • Current studies have shown academic and practical interests in effects of various factors on fundraising effectiveness in social service organizations. However, they hardly suggested what factors affect fundraising effectiveness in a clear way. This study intended to suggest a structural relations between factors, such as professional leadership, environmental competitiveness, market orientation, and fundraising effectiveness. The results of the structural equation modelling analysis showed that there were not significant direct effects of professional leadership and environmental competitiveness on fundraising effectiveness, but their indirect effects and mediating effect of market orientation toward donors. Although the study has a limitation to generalize the results for all kinds of nonprofit social service organizations, it has both academic and practical implications to introduce the concept of market orientation for an explanation of fundraising effectiveness, and also to indicate the importance of organizational efforts to keep strong and sound relationships with donors.

Bispecific Antibody-Bound T Cells as a Novel Anticancer Immunotherapy

  • Cho, Jaewon;Tae, Nara;Ahn, Jae-Hee;Chang, Sun-Young;Ko, Hyun-Jeong;Kim, Dae Hee
    • Biomolecules & Therapeutics
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    • v.30 no.5
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    • pp.418-426
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    • 2022
  • Chimeric antigen receptor T (CAR-T) cell therapy is one of the promising anticancer treatments. It shows a high overall response rate with complete response to blood cancer. However, there is a limitation to solid tumor treatment. Additionally, this currently approved therapy exhibits side effects such as cytokine release syndrome and neurotoxicity. Alternatively, bispecific antibody is an innovative therapeutic tool that simultaneously engages specific immune cells to disease-related target cells. Since programmed death ligand 1 (PD-L1) is an immune checkpoint molecule highly expressed in some cancer cells, in the current study, we generated αCD3xαPD-L1 bispecific antibody (BiTE) which can engage T cells to PD-L1+ cancer cells. We observed that the BiTE-bound OT-1 T cells effectively killed cancer cells in vitro and in vivo. They substantially increased the recruitment of effector memory CD8+ T cells having CD8+CD44+CD62Llow phenotype in tumor. Interestingly, we also observed that BiTE-bound polyclonal T cells showed highly efficacious tumor killing activity in vivo in comparison with the direct intravenous treatment of bispecific antibody, suggesting that PD-L1-directed migration and engagement of activated T cells might increase cancer cell killing. Additionally, BiTE-bound CAR-T cells which targets human Her-2/neu exhibited enhanced killing effect on Her-2-expressing cancer cells in vivo, suggesting that this could be a novel therapeutic regimen. Collectively, our results suggested that engaging activated T cells with cancer cells using αCD3xαPD-L1 BiTE could be an innovative next generation anticancer therapy which exerts simultaneous inhibitory functions on PD-L1 as well as increasing the infiltration of activated T cells having effector memory phenotype in tumor site.

An automatic rotating annular flume for cohesive sediment erosion experiments: Calibration and preliminary results

  • Steven Figueroa;Minwoo Son
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.319-319
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    • 2023
  • Flows of water in the environment (e.g. in a river or estuary) generally occur in complex conditions. This complexity can hinder a general understanding of flows and their related sedimentary processes, such as erosion and deposition. To gain insight in simplified, controlled conditions, hydraulic flumes are a popular type of laboratory research equipment. Linear flumes use pumps to recirculation water. This isn't appropriate for the investigation of cohesive sediments as pumps can break fragile cohesive sediment flocs. To overcome this limitation, the rotating annular flume (RAF) was developed. While not having pumps, a side-effect is that unwanted secondary circulations can occur. To counteract this, the top and bottom lid rotate in opposite directions. Furthermore, a larger flume is considered better as it has less curvature and secondary circulation. While only a few RAFs exist, they are important for theoretical research which often underlies numerical models. Many of the first-generation of RAFs have come into disrepair. As new measurement techniques and models become available, there is still a need to research cohesive sediment erosion and deposition in facilities such as a RAF. New RAFs also can have the advantage of being automatic instead of manually operated, thus improving data quality. To further advance our understanding of cohesive sediment erosion and deposition processes, a large, automatic RAF (1.72 m radius, 0.495 m channel depth, 0.275 m channel width) has been constructed at the Hydraulic Laboratory at Chungnam National University (CNU), Korea. The RAF has the ability to simulate both unidirectional (river) and bidirectional (tide) flows with supporting instrumentation for measuring turbulence, bed shear stress, suspended sediment concentraiton, floc size, bed level, and bed density. Here we present the current status and future prospect of the CNU RAF. In the future, calibration of the rotation rate with bed shear stress and experiments with unidirectional and bidirectional flow using cohesive kaolinite are expected. Preliminary results indicate that the CNU RAF is a valuable tool for fundamental cohesive sediment transport research.

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Study of Al Doping Effect on HfO2 Dielectric Thin Film Using PEALD (PEALD를 이용한 HfO2 유전박막의 Al 도핑 효과 연구)

  • Min Jung Oh;Ji Na Song;Seul Gi Kang;Bo Joong Kim;Chang-Bun Yoon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.36 no.2
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    • pp.125-128
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    • 2023
  • Recently, as the process of the MOS device becomes more detailed, and the degree of integration thereof increases, many problems such as leakage current due to an increase in electron tunneling due to the thickness of SiO2 used as a gate oxide have occurred. In order to overcome the limitation of SiO2, many studies have been conducted on HfO2 that has a thermodynamic stability with silicon during processing, has a higher dielectric constant than SiO2, and has an appropriate band gap. In this study, HfO2, which is attracting attention in various fields, was doped with Al and the change in properties according to its concentration was studied. Al-doped HfO2 thin film was deposited using Plasma Enhanced Atomic Layer Deposition (PEALD), and the structural and electrical characteristics of the fabricated MIM device were evaluated. The results of this study are expected to make an essential cornerstone in the future field of next-generation semiconductor device materials.

A Systematic Review of the Dual-Task Training for Stroke With Hemiplegia (뇌졸중 환자에게 적용한 이중과제 훈련이 미치는 효과에 대한 체계적 고찰)

  • Lee, Yei-Jin;Jung, Min-Ye
    • Therapeutic Science for Rehabilitation
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    • v.5 no.1
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    • pp.23-32
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    • 2016
  • Objective : To investigate the current international researches which identify the effect of stroke with hemiplegia after dual-task training Methods : We systematically examined journals published from 2007 to 2015, searching PubMed. Total 5 researches were selected for the analyses. Results : Selected studies were all in international journal and they used two group experimental design. In addition, all the paper got PEDro scores above 6. They conducted gait task for motor task, at the same time used various domain of cognitive task such as from sustain attention to working memory. The outcome measure tools used for evaluation by the standardized assessment tool and operational definition, further also included the assessment tool designed for the dual-task training such as a variety of tools make possible to assess various aspects of effect. Discussion : Dual-task training in this study was found to give a positive effect on the dual-task performance, as well as improving the motor and cognitive function in patients with stroke. However there were also limitation to the studies conducted so far. In order to apply the occupational therapy, this results can consider as the preliminary data which suggest supplement point and can be a evidence for effective treatment for stroke with hemiplegia.

The Longitudinal Effect of Vocational Identity on Career Outcomes of Individuals Transitioning to Adulthood: Focusing on Career Flexibility (대학졸업예정자의 진로정체감 발달과정이 이후의 진로결과에 미치는 영향: 진로유연성을 중심으로)

  • Lee, Sujung;Kim, Eunjin;Lee, Bora
    • Journal of vocational education research
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    • v.37 no.4
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    • pp.67-89
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    • 2018
  • The purpose of this study is to analyze the role of career flexibility on employment status, career growth, and job satisfaction longitudinally. Demographic information(gender, age, parent's income level, and students' perceived financial states of family), vocational identity, employment status, career growth, and job satisfaction at 1, 2, and 3 years after the first data collection with a sample of 259(time 1), 229(time 2), 182(time 3) were collected respectively. Multivariate regression and logistic regression analysis were performed. Results showed that in-breadth career exploration positively predicted to employment status at time 1, 2, 3 consistently and career flexibility also positively predicted to employment status at time 2, 3. The longitudinal effect of career flexibility was found that the expectancy of career flexibility had shown to have stronger effect. In addition, career growth was influenced by in-depth career exploration at time 2, 3. On the other hand, no variables were related to job satisfaction in this study. Results of the current study provided the new insights for career education and limitation and future suggestions were discussed.

A Novel Therapeutic Effect of a New Variant of CTLA4-Ig with Four Antennas That Are Terminally Capped with Sialic Acid in the CTLA4 Region

  • Piao, Yongwei;Yun, So Yoon;Kim, Hee Soo;Park, Bo Kyung;Ha, Hae Chan;Fu, Zhicheng;Jang, Ji Min;Back, Moon Jung;Shin, In Chul;Won, Jong Hoon;Kim, Dae Kyong
    • Biomolecules & Therapeutics
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    • v.30 no.6
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    • pp.529-539
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    • 2022
  • Rheumatoid arthritis (RA) is a multifactorial immune-mediated disease, the pathogenesis of which involves different cell types. T-cell activation plays an important role in RA. Therefore, inhibiting T-cell activation is one of the current therapeutic strategies. Cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig), also known as abatacept, reduces cytokine secretion by inhibiting T-cell activation. To achieve a homeostatic therapeutic effect, CTLA4-Ig has to be administered repeatedly over several weeks, which limits its applicability in RA treatment. To overcome this limitation, we increased the number of sialic acid-capped antennas by genetically engineering the CTLA4 region to increase the therapeutic effect of CTLA4-Ig. N-acetylglucosaminyltransferase (GnT) and α2,6-sialyltransferase (α2,6-ST) were co-overexpressed in Chinese hamster ovary (CHO) cells to generate a highly sialylated CTLA4-Ig fusion protein, named ST6. The therapeutic and immunogenic effects of ST6 and CTLA4-Ig were compared. ST6 dose-dependently decreased paw edema in a mouse model of collagen-induced arthritis and reduced cytokine levels in a co-culture cell assay in a similar manner to CTLA4-Ig. ST6- and CTLA4-Ig-induced T cell-derived cytokines were examined in CD4 T cells isolated from peripheral blood mononuclear cells after cell killing through irradiation followed by flow- and magnetic-bead-assisted separation. Interestingly, compared to CTLA4-Ig, ST6 was substantially less immunogenic and more stable and durable. Our data suggest that ST6 can serve as a novel, less immunogenic therapeutic strategy for patients with RA.

A Study on Comics Outreach Programs for Contents marginalized Areas (콘텐츠 소외지역의 만화 아웃리치 프로그램 모델링 연구)

  • Lee, Seung-Jin
    • Cartoon and Animation Studies
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    • s.49
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    • pp.359-382
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    • 2017
  • Content is the complex of art and technology of trend, so it is important to experience different technologies for content education. Today, many non-profit organizations plan and operate numbers of programs for disabilities, low-income, and minority families to enhance the quality of life and the realization of social integration. These programs are limited to museums and galleries, not so pro-actively in progressing. Various contend education is necessary to the expansion of cultural exchange for the culturally alienated area. Naver is running an outreach program named . It is an experience-based outreach program where current cartoon / webtoon writers come directly to the school to inform students about the basic story of comics and comic techniques. However, the fact that the is not centered on the marginalized area but is centered on the Seoul Gyeonggi area, has the limitation that they can not benefit from a wide range of programs because they have a space limit of 'school', and, has a spatial limitation that the experience of the work is excluded. 'Outreach programs in marginalized areas' must be reorganized into a fluid dimension, not a fixed, single-system program. You should be able to experience and experience your work by directly using various professional equipment of comics based on your capacity and experience, local culture, religion, and society. These program participants will gain the effect of attractive and effective learning with empathy with their comic experience. Meanings of Comics content outreach program are following: First, the rich cultural archive can be used efficiently by providing various contents to existing outreach programs with the educational limitation of museums and galleries. Second, Comics contents can be enjoyed as a part of our life by understanding diversity and technology of contents. Third, because it is the program of expertise' participation, it can remodel, and restructure the severed experience in remote areas for the continuous growth and development, and furthermore, it can enhance the understanding of society.

Development of Performance Indicators Based on Balanced Score Card for School Food Service Facilities (균형성과표(BSC)개념을 적응한 학교급식 운영성과 측정지표 개발)

  • Kwak, Tong-Kyung;Chang, Hye-Ja;Song, Ji-Yong
    • Korean Journal of Community Nutrition
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    • v.10 no.6
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    • pp.905-919
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    • 2005
  • This study raised the necessity of developing performance indicators for measuring the management efficiency and effectiveness of school food service, and as a means of helping its implementation, a balanced score card (BSC) approach developed by Norton and Kaplan was adopted. This study established BSC in seven phases through literature: Phase 1 Defining a school food service and the scope of working activities, Phase 2 Establishing the vision of a school food service, Phase 3 Setting strategic goals, Phase 4 Identifying critical success factors (CSFs), Phase 5 Developing Key Performance Indicators (KPIs), Phase 6 Extracting cause and effect relationship, and Phase 7 Completing a preliminary BSC. The preliminary BSC was fumed into a survey, which was administered to food service related people working at the Office of Education and School Food Service including 16 offices,209 dietitians, 48 school administrators both from self-operated and contract-managed, and 9 experts in areas related to school food service. They were asked questions about strategies from 4 different perspectives,12 CSFs, 39 KPls, and the cause and effect relationships among them. As a result, among the CSFs based on 4 different perspectives, all factors other than ' zero sum on profit/loss ' from the financial perspective turned out to be valid. In terms of KPIs, manufacturing cost percentages, casualty loss count/reduction rates, school foodervice participation rates, and sales goal achievement rates were found to be valid from the financial perspective, while student satisfaction index, faculty satisfaction index, leftover ratio, nutrition educational performance count, index of evaluating nutrition education, customer claim count/reduction rate, handling customer claim count/reduction rate, and parent satisfaction index were found to be valid from the customers' perspective. Besides, nutritional requirement sufficient ratio, nutritional management score, food poisoning outbreak count, employee safety accident count, sanitary inspection assessment index, meals per labor hour (productivity index), computerization ratio, operational management index, and purchase management assessment index were also found to be valid from the perspective of internal business processes. From the perspective of innovation and learning, employee turnover ratio/rate of absenteeism, annual education and training count, employee satisfaction index, human resource management assessment index, annual menu-related customer feedback, food service information index for employees and parents/schools were also found to be valid. The significance of this study is to present indices for measuring overall performance of school lunch food service operations without putting any limitation on types of school food service management, and to help correctly assess the contribution of the current types of school food service management to schools and students. (Korean J Community Nutrition 10(6) : $905\∼919$, 2005)