• Title/Summary/Keyword: Transmission control

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Design and Implementation of National Language Ability Test System using Korean Style Internet-Based Test added Middle-Server (미들서버방식 한국형 IBT를 이용한 국가언어능력평가 시스템의 설계 및 구현)

  • Chang, Young-Hyun;Park, Dea-Woo
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.9
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    • pp.185-192
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    • 2011
  • The purpose of this paper is to propose the design and implementation of a korean style internet-based test system on the basis of efficiency and stability for middle server. The current assessment system has some unstable elements with regard to transmission procedure, cost, system load and stability. This paper proposes a series of activities for the performance improvement of korean style internet-based test system which finally produced various excellent results in the administration of expense control, human resources, and special operational affairs. The proposed system's technological factors using middle server have been tested through a basic simulation pilot system. Actual development procedure starts from the analysis required by improving the shortcomings of existing internet-based test systems. A efficiency comparison with existing system and newly developed system was made in the area of number of operators, abnormal processing, system maintenances. Korean style internet-based test system using middle server has shown great efficiency increased to the maximum of 2 times about the effectiveness of processing for various parts. The korean style internet-based test system using middle server have been given good evaluations with regard to the convenience of their use and the management system for operators and supervisors.

Design and Implementation of Data Distribution Management Module for IEEE 1516 HLA/RTI (IEEE 1516 HLA/RTI 표준을 만족하는 데이터 분산 관리 모듈의 설계 및 구현)

  • Ahn, Jung-Hyun;Hong, Jeong-Hee;Kim, Tag-Gon
    • Journal of the Korea Society for Simulation
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    • v.17 no.2
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    • pp.21-29
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    • 2008
  • The High Level Architecture(HLA) specifies a framework for interoperation between heterogeneous simulators, and Run-Time Infrastructure(RTI) is a implementation of the HLA Interface Specification. The Data Distribution Management(DDM) services, one category of IEEE 1516 HLA/RTI management services, control filters for data transmission and reception of data volume among simulators. In this paper, we propose design concept of DDM and show its implementation for light-weighted RTI. The design concept of DDM is to minimize total amount of message that each federate and a federation process generate using the rate of RTI service execution. The design of our proposed DDM follows that a data transfer mechanism is differently applied as the rate of RTI service execution. A federate usually publishes or subscribes data when it starts. The federate constantly updates the data and modifies associated regions while it continues to advance its simulation time. Therefore, the proposed DDM design provides fast update or region modification in exchange of complex publish and subscribe services. We describe how to process the proposed DDM in IEEE 1516 HLA/RTI and experiment variable scenarios while modifying region, changing overlap ratio, and increasing data volume.

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The Effect of Lithospermum erythrorhizon Extracts in UVB-Irradiated Mouse Skin (자초(Lithospermum erythrorhizon) 추출물이 UVB로 조사된 생쥐 피부에 미치는 영향)

  • Song, Seon-Young
    • Applied Microscopy
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    • v.38 no.3
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    • pp.195-204
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    • 2008
  • This study was intended to identify the effectiveness of Lithospermum erythrorhizon in the UVB-irradiated mouse skin. The C57BL mice were divided into three groups; the control group, the UVB irradiated group(UVB group), and the group treated with Lithospermum erythrorhizon extracts after UVB irradiation(UVB+Le group). 10 mouses were collected and sacrificed at 24 hrs, 48 hrs, 72 hrs, 120 hrs, and 168 hrs, respectively. In the result, the transepidermal water loss (TEWL) was decreased the UVB+Le group than UVB groups by time. At the 168 hrs group was significantly lower(p<0.05). In the result, the melanin value was decreased in the UVB+Le group than UVB group, but meaningless(p>0.05). In the result of erythema index, the UVB+Le group was meaningfully lower at 24 hrs, 48 hrs, and 72 hrs group than UVB group(p<0.05). In the result of scanning electron micrograph observation, the UVB+Le group was allevited swelling than UVB group at the 24 hrs, formation of the scab at the 48 hrs, regular plate shap at the 72 hrs, new keratin observated at the 120 hrs partially, and fine fiber covered epidermis surface at the 168 hrs. In the result of transmission electron micrograph observation, the UVB+Le group was facilitation of increased lamellar bodies and reformation lamellar bodies than UVB group at the all groups. Almost all the structures were recovered at the 160 hrs group. In conclusion, Lithospermum erythrorhizon extracts may recovery on the UVB-irradiated mouse skin.

A Study on Radio-Protection Mechanism of Platelet Cells After Injection of Alliin (알리인 투여 후 혈소판의 방사선 방어기전 연구)

  • Ji, Tae-Jeong
    • Journal of radiological science and technology
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    • v.33 no.3
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    • pp.185-192
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    • 2010
  • Platelets originating from Megakaryocyte are sensitive to radiation along with white blood cells, and thus these platelets are used as an index of radiation hazard as they decrease in advance. Thus, when there is a scarcity of platelets, dot hemorrhage occurs and it leads to decrease of blood corpuscle and a decline in immunity. In particular, when 4~6 Gy whole body irradiation is received, after three weeks, the platelets will decrease to the lowest level, which can be a cause of death by bleeding and anemia. Therefore, this study tried to identify the mechanism of platelet damage and protection effect. The protection substance used in the experiment is Alliin, which is a component of garlic, and it was observed by an Transmission Electron Microscope(TEM) after its injection to the rat's tail vein. In the study, it was found that the cell membrane was severely damaged in a 10-day progressed platelet organ after receiving 5 Gy irradiation. It billowed as balloon-like figure and the glycocalyx became hyperplasia. The minute organ was damaged to the point that it was beyond recognition in a 20-day progressed platelet organ after receiving irradiation, and the cytoplasmic contents were exposed to epilepsy parts and outrageously damaged. Furthermore, the form of granules could also not be observed. A hole was formed in the middle, and the damaged organ was found in a 30-day progressed platelet. However, the form of granules was consistently maintained in the experiment group injecting Alliin, as with the control group, and there was no damage to the cell membrane recognized. Thus, it was possible to verify the effectiveness of radiation protection of the platelet when Alliin was injected to the blood vessel.

Assessment on Thermal Transmission Property of Wall Through a Scaled Model Test (축소모형 실험을 통한 벽체의 열관류 측정)

  • Chang, Yoon-Seong;Kim, Sejong;Shim, Kug-Bo;Lee, Sang-Joon;Han, Yeonjung;Park, Yonggun;Yeo, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.6
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    • pp.884-889
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    • 2015
  • Appropriate evaluation of thermal insulation property of structural member and valid control of cooling/heating energy are important for improving building's energy efficiency. The typical heating system of house in Korea is the floor heating one. The radiation heating system is not only appropriate to climate and geographic conditions of Korea, but also advantageous to provide emotional comfort by the warm feeling of floor. Based on living conditions in Korea, scaled models of the wooden house and concrete house were designed. The ceiling was made of styrofoam insulation and the four sided walls and bottom were made of plywood and concrete, respectively. The floor was heated by heating film. Indoor vertical temperature distributions by floor heating system were measured by thermocouple, and surface temperatures on walls were measured by infrared thermography. Also, thermal insulation property of wooden wall was evaluated to build database for improving energy efficiency of wooden building. It is expected that collected data during tests of various types of floor and wall composition could be referenced for evaluating thermal environment of actual conditions of houses.

Possibility of Involvement of Porphyromonas gingivalis in Coronary Heart Disease

  • Lee, Jin-Yong;Park, Byung-Lae;Yun, Hyun-Kyung;Park, Eun-Ah;Shin, Eun-Ah;Jue, Seong-Suk;Shin, Je-Won
    • The Journal of the Korean Society for Microbiology
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    • v.35 no.3
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    • pp.203-214
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    • 2000
  • Porphyromonas gingivalis has been implicated in periodontal diseases. Accumulating evidence suggests that cardiovascular disease is the most prevalent medical problem in patients with periodontal diseases. In order to check the possibility that P. gingivalis is involved in coronary heart disease, the present study was performed to observe P. gingivalis adherence and invasion of human coronary artery endothelial cells (HCAEC) and production of cytokines and growth factors by HCAEC upon P. gingivalis infection. $^3H$-labeled P. gingivalis 381 was incubated with HCAEC for 90 min. The radioactivity of the washed HCAEC was a measure of the absorbed (adhering and invading) P. gingivalis. The absorption radioactivity of the HCAEC infected by P. gingivalis was determined to be 59.58% of the input bacterial cells. In contrast, the absorption radioactivity of the cells infected by S. gordonii Challis which was employed as a control was negligible (0.59%). DPG3, a P. gingivalis mutant defective of fimbriae, appeared to be impaired to some extent in capability of adherence/invasion as compared to that of the parental strain 381, showing 43.04% of the absorption radioactivity. The absorption radioactivity of the HCAEC infected by P. gingivalis 381 in the presence of excessive fimbriae at the concentrations of $50\;{\mu}g$ and $100\;{\mu}g/ml$ was 57.27 and 45.44%, respectively. Invasion of HCAEC by P. gingivalis 381 was observed by an antibiotic (metronidazole) protection assay and transmission electron microscopy (TEM). In the antibiotic protection assay, invasion by the bacterium was measured to be 0.73, 1.09, and 1.51% of the input bacterial cells after incubation for 30, 60, and 90 min, respectively. Invasion by DPG3 was shown to be 0.16% after 90-min incubation. In comparison of invasion efficiency at 90 min of the incubation, the invasion efficiency of DPG3 was 0.37% while that of its parental strain 381 was 2.54%. The immunoblot analysis revealed fimbriae of P. gingivalis did not interact with the surface of HCAEC. These results suggest that fimbriae are not the major contribution to the adherence of P. gingivalis to HCAEC but may be important in the invasion of HCAEC by the bacterium. The presence of cytochalasin D ($1\;{\mu}g/ml$) and staurosporine ($1\;{\mu}M$) reduced the invasion of HCAEC by P. gingivalis 381 by 78.86 and 53.76%, respectively, indicating that cytoskeletal rearrangement and protein kinase of HCAEC are essential for the invasion. Infection of P. gingivalis induced HCAEC to increase the production of TNF-${\alpha}$. by 60.6%. At 90 min of the incubation, the HCAEC infected with P. gingivalis cells was apparently atypical in the shape, showing loss of the nuclear membrane and subcellular organelles. The overall results suggest that P. gingivalis may cause coronary heart disease by adhering to and invading endothelial cells, and subsequently damaging the cells.

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Design and Implementation of Bio-data Monitering System Based on ISO/IEEE 11073 DIM/REST for IoT Healthcare Service (IoT 헬스케어 서비스를 위한 ISO/IEEE 11073 DIM/REST 기반 생체정보 모니터링 시스템 설계 및 구현)

  • Choi, Ju-Hyun;Chun, Seung-Man;Jang, Dong-Hyun;Park, Jong-Tae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.3
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    • pp.3-12
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    • 2015
  • Recently, various studies have been attempted to provide a biological information monitoring service through integrating with the web service. The medical information transmission standard ISO/IEEE 11073 PHD defines the optimized exchange protocol ISO/IEEE 11073-20601 based on the No-IP to exchange the biometric information between the ISO/IEEE 11073 agent and the manager. It's system structure based on the No-IP using ISO/IEEE 11073-20601 is not suitable for providing a remote biological information monitoring services. That is because it is difficult to provide to control and manage the biological information measurement devices, which have installed IP protocol stack at the remote. Furthermore, ACSE and CMDISE in ISO/IEEE 11073-20601 are not suitable to provide U-healthcare services based on IoT because they are complicated and difficult to implement it caused by the structural complexity. In order to solve the problems, in this paper, we propose the biological information monitoring architecture based on ISO/IEEE 11073 DIM/REST of IoT environment to provide the biological information monitoring service based on IoT. To do this, we designed biological information monitoring system architecture based on IoT and the message exchange protocol of ISO/IEEE 11073 DIM/REST between the ISO/IEEE 11073 agent and the ISO/IEEE 11073 manager. In order to verify the realistic possibility of the proposed system architecture, we developed the service prototype.

A Study on Real Time Traffic Performance Improvement Considering QoS in IEEE 802.15.6 WBAN Environments (IEEE 802.15.6 WBAN 환경에서 QoS를 고려한 실시간 트래픽 성능향상에 관한 연구)

  • Ro, Seung-Min;Kim, Chung-Ho;Kang, Chul-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.4
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    • pp.84-91
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    • 2011
  • Recently, WBAN(Wireless Body Area Network) which has progressed standardization based on IEEE 802.15.6 standardization is a network for the purpose of the short-range wireless communications within around 3 meters from the inner or outer human body. Effective QoS control technique and data efficient management in limited bandwidth such as audio and video are important elements in terms of users and loads in short-range wireless networks. In this paper, for high-speed WBAN IEEE 802.15.6 standard, the dynamic allocation to give an efficient bandwidth management and weighted fair queueing algorithm have been proposed through the adjustment of the super-frame about limited data and Quality of Service (QoS) based on the queuing algorithm. Weighted Fair Queueing(WFQ) Algorithm represents the robust performance about elements to qualitative aspects as well as maintaining fairness and maximization of system performance. The performance results show that the dynamic allocation expanded transmission bandwidth five times and the weighted fair queueing increased maximum 24.3 % throughput and also resolved delay bound problem.

The Lived Experience of Mothers of Children with Muscular Dystrophy (근디스트로피 자녀를 가진 어머니의 경험)

  • Oh Sang-Eun
    • Child Health Nursing Research
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    • v.7 no.4
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    • pp.421-433
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    • 2001
  • The purpose of this phenomenological study was to understand the lived experience of mothers of children with muscular dystrophy. The participants were 11 mothers recruited by snowball sampling, who agreed with the objectives of the research and could verbally communicate with the researcher and who lived with their sons who had muscular dystrophy. Data collection was done through in-depth interviews with participants in their own homes. Each interview took 50 to 120 minutes. All of the interviews were audiotaped and then transcribed. Data were analyzed using Colaizzi's (1978) method of phenomenology. From the transcripts 109 significant sentences and phrases were selected and 13 clusters of themes were categorized from 67 significant statements. These results were integrated into the essential structure of the lived experience of mothers of children with muscular dystrophy. 1. Anxious and relying on chance due to indefinite diagnosis. 2. Only able to cry with shock because of son's fatal disease. 3. Seeing the future as dismal and feeling resentment that this disease in transmitted through the mother. 4. Feeling caught between a husband who is distancing himself from his family and the family which is disintegrating. 5. Feeling like a sinner for transmission of genetic disease(Feeling guilt for conceiving a son with a genetically transmitted fatal disease). 6. Empathizing with other suffers of muscular dystropy and their parents in their grief and helping to dissipate their heavy feelings. 7. Deciding to sacrifice self as a way of taking responsibility for giving birth to a handi-capped son. 8. Losing hope (feeling despair) as son's condition deteriorates in spite of all attempts to help him. 9. Wishing to die with son who becomes progressively immobile. 10. Accumulating Han*(한, 恨), because of rising Hwa(화, anger), and becoming sick both mentally and physically. 11. Seeing events as destiny and finding self-control through faith. 12. Finally, giving up sacrificing self for son and becoming concerned(involved) with other children in the family. 13. Feeling fear at son's impending death. This is the first research on the experience of Korean mothers of children with muscular dystrophy. In applying the phenomenology research method, this study not only helps health professionals understand the experience of these mothers in the Korean patriarchal social system, but the researcher, as a nurse, can share their agony and grief through identification of their inner world through in-depth personal interviews. The results obtained in this study will not only help in the development of family nursing practice for families with genetically transmitted diseases but also prepare basic data for family nursing practice in the Korean sociocultural context.

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Performance Comparison of TCP and SCTP in Wired and Wireless Internet Environment (유무선 인터넷 환경에서 TCP와 SCTP의 성능 비교)

  • Sasikala, Sasikala;Seo, Tae-Jung;Lee, Yong-Jin
    • 대한공업교육학회지
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    • v.33 no.2
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    • pp.287-299
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    • 2008
  • HTTP is one of the most widely used protocols of the WWW. Currently it uses TCP as the transport layer protocol to provide reliability. The HTTP uses separate TCP connection for each file request and adds unnecessary head-of-line blocking overhead for the file retrieval. The web application is short sized and affected by the increased handover latency of TCP in wireless environment. SCTP has attractive features such as multi-streaming and multi-homing. SCTP's multi-streaming and multi-homing avoid head-of-line blocking problem of TCP and reduce handover latency of TCP in wired and wireless environment. Mean response time is the important measure in most web application. In this paper, we present the comparison of mean response time between HTTP over SCTP with that of HTTP over TCP in wired and wireless environments using NS-2 simulator. We measured mean response time for varying packet loss rate, bandwidth, RTT, and the number of web objects in wired environment and mean response time and packet loss rate for varying moving speed and region size in wireless environment. Our experimental result shows that SCTP reduces the mean response time of TCP based web traffic.