• Journal of KIISE:Computer Systems and Theory
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• v.26 no.7
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• pp.813-826
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• 1999

실시간 멀티미디어 응용의 등장으로 멀티캐스트와 QoS(Quality of Service) 지원이 필수적인 망 서비스로 부각되고 있다. 이에, ATM 기반의 인터넷에서 IP 멀티캐스트의 효율적인 처리를 위하여 MARS(Multicast Address Resolution Server)가 제안되었고, 기존의 최선 서비스 기반의 인터넷에서 QoS(Quality of Service)를 지원하기 위하여 RSVP(Resource Reservation Protocol)가 제안되었다. 본 논문에서는 ATM 망에서 QoS가 지원되는 IP 멀티캐스트 서비스를 제공하기 위하여 MARS 구조에서 RSVP를 지원하는 두 가지 방안을 제안하고, 시뮬레이션을 통하여 그 성능을 분석하였다. 제안하는 두 가지 방법은 각각 'RSVP 전 홉 노드 방식'과 'MARS 서버 방식'이라 명명하였다. RSVP 전 홉 노드 방식은 송신원으로부터 ATM 망으로 진입하는 노드와 수신원을 향하여 ATM 망을 진출하는 노드 간에 각각 일대일 양방향 VC를 설정하여 멀티캐스트 그룹에 속하는 수신원들이 보내는 자원 예약 메시지를 ATM 망에서 전송하는 방안이다. MARS 서버 방식은 ATM 망을 진출하는 노드와 MARS 서버간에 MARS 제어 메시지 교환을 위해 존재하는 ATM VC를 사용하여 RSVP의 자원 예약 메시지를 전송하고, MARS 서버가 RSVP 자원 예약 메시지를 처리하도록 그 기능을 확장함으로써 ATM 망에서 필요로 하는 제어 VC 수를 절약할 수 있는 방안이다. 시뮬레이션을 통하여, MARS 서버 방식은 ATM 제어 VC의 수를 절약할 수 있을 뿐 아니라 경우에 따라 RSVP 자원 예약 메시지 전달 지연을 줄일 수도 있음을 볼 수 있었다. 그러나, MARS 클러스터 내에 동시에 존재하는 RSVP 흐름이 많을 때에는 MARS 서버 방식의 경우 MARS 서버에서의 병목 현상으로 인해 성능이 저하될 수 있다.Abstract Emerging real time multimedia applications require multicast service with a QoS(Quality of Service) support. An overlay service architecture MARS(Multicast Address Resolution Server) is proposed to support IP multicast over an ATM network, and a resource reservation protocol RSVP is proposed to provide QoS support in the Internet which is originally based upon best effort service only. In this paper, we propose two schemes to support IP multicast service with QoS support over ATM networks: 'RSVP Previous Hop Node(RPHN) scheme' and 'MARS server based scheme'. In RPHN scheme, the RSVP reservation messages are transported via one-to-one ATM control VC from the egress nodes to the ingress nodes of the the multicast flow set up between each pair of nodes. The RSVP message processing occurs at the ingress nodes of the multicast flow. Whereas, in the MARS server based scheme, the RSVP reservation messages are transported via the MARS control VCs between the egress nodes and the MARS server. The RSVP message processing burden is imposed at MARS server in this scheme. For MARS server based scheme, no additional ATM VC is required for RSVP reservation message transmission, while the processing burden at the MARS server is high. Simulation results show that the MARS server based scheme, may accomplish RSVP reservation message delivery with smaller delay as well as saving of the number of ATM VCs. When the number of simultaneous RSVP flows in the MARS cluster is large, however, MARS based scheme may suffer performance degradation since MARS server becomes a performance bottleneck.

• Korean Journal of Construction Engineering and Management
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• v.22 no.2
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• pp.12-20
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• 2021

Unsafe working environments slow down working speed in that it takes a lot of time to respond in case of an accident, greatly reducing the productivity of construction work. Therefore, proper safety management that does not impede the productivity of construction works is a very important factor for successful construction project. However especially in mega project, the mutual effects of safety management and productivity are complex. Therefore, this study establishes a causal model between safety management and productivity influencing factors based on effectiveness metrics, and analyzes the effect of increased site congestion due to excessive personnel input, irregular safety measures and inefficient change of work schedules. The result of this study, is expected to contribute to enhancing the competitiveness of the construction industry as the basis for establishing a safety management plan that can secure appropriate productivity.

• Journal of the Korean Society for information Management
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• v.38 no.1
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• pp.71-86
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• 2021

This study attempted to discover the problems related to the increasing book disposal trend within academic libraries by analyzing the disposal status over ten years and interviews with the librarians. The analysis utilized Korea Education and Research Information Service provided disposal information from 2010 to 2019. The academic libraries with more than 2 million books had disposed of the most number of books. This trend led to a distinctive decrease in the books' duplicate copies in terms of the collection composition. The librarians from the organizations, which conducted disposal more than three times and one massive removal within ten years, revealed in the interviews that they discarded many valuable duplicate books. They discussed the importance of digitizing high-value resources and also the limitation imposed by the copyright law. In conclusion, this study pointed out that book disposal can cause changes in the collection composition in the long run and suggested that academic libraries pay attention to these changes. The study also suggested evaluating the discarded books' values to guide the digitization efforts and count the number of books to include digital book use rights.

• Journal of fish pathology
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• v.35 no.1
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• pp.27-40
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• 2022

Yellow head virus (YHV), Infectious hypodermal and hematopoietic necrosis (IHHNV), Taura syndrome virus (TSV), and Infectious myositis virus (IMNV) cause serious mortality to Penaeidae shrimp in the aquaculture. In this study, YHV, IHHNV, TSV, and IMNV were surveyed from imported frozen shrimps between 2019 and 2020 via molecular diagnostic assay. Among 10 shrimp groups, YHV (n=1) and IHHNV (n=4) were detected by RT-PCR and PCR, respectively. From the phylogenetic analysis based on the partial ORF 1b region of YHV, YHV was classified into YHV genotype 3 (YHV3). And IHHNVs (n=2) detected from Litopenaeus vannamei belong to infectious IHHNV type 2. Although IHHNVs (n=2) identified from Penaeus monodon showed PCR positive results (MG 831F/R primer set), the sequences of ORF 2 and 3 were not amplified, suggesting that those samples might possess type A IHHNV related sequence of P. monodon. Furthermore, in the challenge test, even though PCR-detected isolates (YHV3/type A IHHNV related sequence or infectious IHHNV type 2) were not induced mortality to L. vannamei, viral genes were amplified suggesting that the viruses in the frozen shrimp could be non-pathogenic particles which are not enough to induce mortality.

• Phonetics and Speech Sciences
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• v.14 no.1
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• pp.21-28
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• 2022

Previous studies have provided important findings on children's speech production development. They have revealed that essentially all aspects of children's speech shift toward adult-like characteristics over time. Nevertheless, few studies have examined the perceptual aspects of children's speech tokens, as perceived by naive adult listeners. To fill the gap between children's production and adults' perception, we conducted cross-sectional perceptual studies of monosyllabic words produced by children aged two to six years. Monosyllabic words in the consonant-vowel-consonant form were extracted from children's speech samples and presented aurally to five listener groups (20 listeners in total). Generally, the agreement rate between children's production of target words and adult listeners' responses increases with age. The perceptual responses to tokens produced by two-year old children induced the largest discrepancies and the responses to words produced by six years olds agreed the most. Further analyses were conducted to identify the sources of disagreement, including the types of segments and syllable structure. This study makes an important contribution to our understanding of the development and perception of children's speech across age groups.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.4
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• pp.8-16
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• 2023

The importance of next-generation packaging technologies is being emphasized as a solution as the miniaturization of devices reaches its limits. To address the bottleneck issue, there is an increasing need for 2.5D and 3D interconnect pitches. This aims to minimize signal delays while meeting requirements such as small size, low power consumption, and a high number of I/Os. Hybrid bonding technology is gaining attention as an alternative to conventional solder bumps due to their limitations such as miniaturization constraints and reliability issues in high-temperature processes. Recently, there has been active research conducted on SiCN to address and enhance the limitations of the Cu/SiO₂ structure. This paper introduces the advantages of Cu/SiCN over the Cu/SiO₂ structure, taking into account various deposition conditions including precursor, deposition temperature, and substrate temperature. Additionally, it provides insights into the core mechanisms of SiCN, such as the role of Dangling bonds and OH groups, and the effects of plasma surface treatment, which explain the differences from SiO₂. Through this discussion, we aim to ultimately present the achievable advantages of applying the Cu/SiCN hybrid bonding structure.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.79-90
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• 2024

This study focused on user trust in ChatGPT, a generative AI technology, and explored the factors that affect usage status and intention to continue using, and whether the influence of trust varies depending on the purpose. For this purpose, the survey was conducted targeting people in their 20s and 30s who use ChatGPT the most. The statistical analysis deploying IBM SPSS 27 and SmartPLS 4.0. A structural equation model was formulated on the foundation of Bhattacherjee's Expectation-Confirmation Model (ECM), employing path analysis and Multi-Group Analysis (MGA) for hypothesis validation. The main findings are as follows: Firstly, ChatGPT is mainly used for specific needs or objectives rather than as a daily tool. The majority of users are cognizant of its hallucination effects; however, this did not hinder its use. Secondly, the hypothesis testing indicated that independent variables such as expectation- confirmation, perceived usefulness, and user satisfaction all exert a positive influence on the dependent variable, the intention for continuance intention. Thirdly, the influence of trust varied depending on the user's purpose in utilizing ChatGPT. trust was significant when ChatGPT is used for information retrieval but not for creative purposes. This study will be used to solve reliability problems in the process of introducing generative AI in society and companies in the future and to establish policies and derive improvement measures for successful employment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1790-1799
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• 2010

A controlled and double blinded trial was performed to evaluate the effects of OPE supplementation on blood circulation in healthy male smokers. The study population consisted of 92 healthy male smokers aged $44.4{\pm}7.8$ years. The supplement group (n=49) received OPE containing 100 mg quercetin/day for 10 weeks, while the control group (n=43) received placebo powders. The prothrombin time and activated partial thromboplastin time increased significantly after OPE consumption, indicating the attenuated blood clot formation by OPE. In conclusion, these results indicate that the daily consumption of OPE (containing 100 mg quercetin) for 10 weeks exerts significant health benefits through the modulation of physiological functions including the blood circulation in male smokers.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.65-69
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• 2011

Purpose: Normal pancreas has low uptake rate in $^{18}F$-FDG PET scan. However, it is possible to diagnose malignancy of pancreatic cancer which has high uptake rate. Many studies approve a high prevalence of diabetes in pancreatic cancer and if the blood glucose level (BGL) is over the normal range, FDG uptake will be decreased and there will be inconvenience for patients from the delay time to reduce the high BGL or could cause difficulty to arrange the schedule. Therefore, we studied the relation of BGL and image quality in pancreatic cancer on PET. Materials and Methods: A hundred patients had PET scan. The prevalence of pancreatic cancer and diabetes were evaluated using SPSS ver. 17. The fasting BGL of patients were examined and sorted as diabetes mellitus (DM) group and Non-DM group. For the evaluation, patients were divided into 3 groups (Non-DM, DM; BGL${\geq}7.0mmol/L$, and DM; BGL<7.0 mmol/L). The ROI was drown on Liver and Lung for the PET imaging analysis. Results: Fifty three male and forty seven female were in the patients. The average age was $60.1{\pm}13.5$. There were 36 patients (male: 22, female: 14, 36%) who had pancreatic cancer with DM. There were 15 patients who showed over 7.0 mmol/L in their fasting BGL and 85 patients who showed under 7.0 mmol/L in their fasting BGL. Among the Non-DM, DM; BGL${\geq}7.0mmol/L$, and DM; BGL<7.0 mmol/L, there was not a statistical significance (p>0.05). Conclusion: The prevalence of pancreatic cancer was comparatively high in this study. If the fasting BGL was slightly over the normal BGL, we believe it will not give a severe disturbance when the patients have PET scan. Furthermore, the examination schedule doesn't need to change and the inconvenience from the delay of patients preparation will be reduced.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.25-29
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• 2010

To evaluate the usefulness of newly designed percutaneous bone biopsy needle for pumpkin's specimen collection. We manufactured three types of biopsy needle with different internal processing which were made of 10 mm-diameter acrylic material. We made the conventional type (Ct) similar to the clinical type then compared the test group. The type a (Ta) made 1 cm-length internal processing from the distal, type b (Tb) made taper, and type c (Tc) made internal processing like spiral configuration. We performed 20 times biopsy to get an 10 mm length specimen from pumpkin's surface and evaluated the success rate of the biopsy, length of the specimen, and determine internal processing type of the most suitable biopsy needle (ANOVA test). Success rates of Ct, Ta, Tb, and Tc were 55%, 80%, 90%, and 100%, respectively. The lengths of the specimen of Ct, Ta, Tb, and Tc were $5.6{\pm}1.1\;mm$, $5.9{\pm}0.87\;mm$, $3.9{\pm}0.77\;mm$, and $9.4{\pm}0.54\;mm$, respectively. All groups were statistically significant (p < 0.05) except the group between Ct and Ta (p = 0.28). Newly designed bone biopsy needle seems to be useful for obtaining enough specimen. Tc may be more effective than other types.