• Title/Summary/Keyword: concurrent

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A Fast String Matching Scheme without using Buffer for Linux Netfilter based Internet Worm Detection (리눅스 넷필터 기반의 인터넷 웜 탐지에서 버퍼를 이용하지 않는 빠른 스트링 매칭 방법)

  • Kwak, Hu-Keun;Chung, Kyu-Sik
    • The KIPS Transactions:PartC
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    • v.13C no.7 s.110
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    • pp.821-830
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    • 2006
  • As internet worms are spread out worldwide, the detection and filtering of worms becomes one of hot issues in the internet security. As one of implementation methods to detect worms, the Linux Netfilter kernel module can be used. Its basic operation for worm detection is a string matching where coming packet(s) on the network is/are compared with predefined worm signatures(patterns). A worm can appear in a packet or in two (or more) succeeding packets where some part of worm is in the first packet and its remaining part is in its succeeding packet(s). Assuming that the maximum length of a worm pattern is less than 1024 bytes, we need to perform a string matching up to two succeeding packets of 2048 bytes. To do so, Linux Netfilter keeps the previous packet in buffer and performs matching with a combined 2048 byte string of the buffered packet and current packet. As the number of concurrent connections to be handled in the worm detection system increases, the total size of buffer (memory) increases and string matching speed becomes low In this paper, to reduce the memory buffer size and get higher speed of string matching, we propose a string matching scheme without using buffer. The proposed scheme keeps the partial matching result of the previous packet with signatures and has no buffering for previous packet. The partial matching information is used to detect a worm in the two succeeding packets. We implemented the proposed scheme by modifying the Linux Netfilter. Then we compared the modified Linux Netfilter module with the original Linux Netfilter module. Experimental results show that the proposed scheme has 25% lower memory usage and 54% higher speed compared to the original scheme.

The Study of Usability Evaluation in the GUI of Mobile Computing - Based on Benchmark Testing in the interface design of WIPI (Mobile Computing의 GUI 개발에 있어 사용성 평가 연구 - WIPI 인터페이스 디자인을 위한 Benchmark Testing을 중심으로 -)

  • 정봉금;송연승
    • Archives of design research
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    • v.17 no.1
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    • pp.49-62
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    • 2004
  • Due to the recent surge of wireless Internet and concurrent development of the end user terminal devices having standardized graphical user interface(GUI) and unified operation mechanism for better interactivity in information representation and ease of use, various efforts on the improvement of GUI is widely recognized as one of the key factors that will usher in the next stages of the wireless Internet for the users. Especially, improved usability along with unique visual effect are considered to be the key elements for GUI considering the rapid improvement of the resolution and color on the end user handset devices; thus, the study and research on the subject of GUI is expected to increase along with the wireless Internet using smart phones. User interface of the wires Internet end user handsets will have a definite and significant effect on the user interaction as well as productivity. Domestically, wireless Internet service providers and GUI design companies are making various efforts in producing a common GUI models for standardized operation scheme and improved graphical display capabilities of the hand phones, PDAs and smart phones. In the study, Nokia 3650 model and Microsoft Orange SPV model were chosen as test devices for usability comparison and data collection to collect directional benchmark data in developing next generation smart phone user interface integrating PDAs and phones. The mail purpose of this study is to achieve the most efficient user accessibility to WAP menu through intensive focus on developing WIPI WAP menu having most effective usability for the users in their twenties and thirties. The result of this study can also be used as the base research materials for WAP service development, VM browser development and PDA browser development. The result of this study along with the evaluation model is expected to provide effective analysis materials on the subject of user interface to the developers of the wireless Internet user devices, GUI designers and service planners while short listing key factors to consider in developing smart phones therefore serving as the GUI guideline of WIPI phones.

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Update Protocols for Web-Based GIS Applications (웹 기반 GIS 응용을 위한 변경 프로토콜)

  • An, Seong-U;Seo, Yeong-Deok;Kim, Jin-Deok;Hong, Bong-Hui
    • Journal of KIISE:Databases
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    • v.29 no.4
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    • pp.321-333
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    • 2002
  • As web-based services are becoming more and more popular, concurrent updates of spatial data should be possible in the web-based environments in order to use the various services. Web-based GIS applications are characterized by large quantity of data providing and these data should be continuously updated according to various user's requirements. Faced with such an enormous data providing system, it is inefficient for a server to do all of the works of updating spatial data requested by clients. Besides, the HTTP protocol used in the web environment is established under the assumption of 'Connectionless'and 'Stateless'. Lots of problems may occur if the scheme of transaction processing based on the LAN environment is directly applied to the web environment. Especially for long transactions of updating spatial data, it is very difficult to control the concurrency among clients and to keep the consistency of the server data. This paper proposes a solution of keeping consistency during updating directly spatial data in the client-side by resolving the Dormancy Region Lock problem caused by the 'Connectionless'and 'Stateless'feature of the HTTP protocol. The RX(Region-eXclusive) lock and the periodically sending of ALIVE_CLIENTi messages can solve this problem. The protocol designed here is verified as effective enough through implementing in the main memory spatial database system, called CyberMap.

Two-Way Donation Locking for Transaction Management in Distributed Database Systems (분산환경에서 거래관리를 위한 두단계 기부 잠금규약)

  • Rhee, Hae-Kyung;Kim, Ung-Mo
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.12
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    • pp.3447-3455
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    • 1999
  • Database correctness is guaranteed by standard transaction scheduling schemes like two-phase locking for the context of concurrent execution environment in which short-lived ones are normally mixed with long-lived ones. Traditional syntax-oriented serializability notions are considered to be not enough to handle in particular various types of transaction in terms of duration of execution. To deal with this situation, altruistic locking has attempted to reduce delay effect associated with lock release moment by use of the idea of donation. An improved form of altruism has also been deployed in extended altruistic locking in a way that scope of data to be early released is enlarged to include even data initially not intended to be donated. In this paper, we first of all investigated limitations inherent in both altruistic schemes from the perspective of alleviating starvation occasions for transactions in particular of short-lived nature. The idea of two-way donation locking(2DL) has then been experimented to see the effect of more than single donation in distributed database systems. Simulation experiments shows that 2DL outperforms the conventional two-phase locking in terms of the degree of concurrency and average transaction waiting time under the circumstances that the size of long-transaction is in between 5 and 9.

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Prognostic value of nodal SUVmax of 18F-FDG PET/CT in nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

  • Lee, So Jung;Kay, Chul-Seoung;Kim, Yeon-Sil;Son, Seok Hyun;Kim, Myungsoo;Lee, Sea-Won;Kang, Hye Jin
    • Radiation Oncology Journal
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    • v.35 no.4
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    • pp.306-316
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    • 2017
  • Purpose: To investigate the predictive role of maximum standardized uptake value ($SUV_{max}$) of 2-[$^{18}F$]fluoro-2-deoxy-D-glucose($^{18}F-FDG$) positron emission tomography/computed tomography (PET/CT) in nasopharyngeal cancer patients treated with intensity-modulated radiotherapy (IMRT). Materials and Methods: Between October 2006 and April 2016, 53 patients were treated with IMRT in two institutions and their PET/CT at the time of diagnosis was reviewed. The $SUV_{max}$ of their nasopharyngeal lesions and metastatic lymph nodes (LN) was recorded. IMRT was delivered using helical tomotherapy. All patients except for one were treated with concurrent chemoradiation therapy (CCRT). Correlations between $SUV_{max}$ and patients' survival and recurrence were analyzed. Results: At a median follow-up time of 31.5 months (range, 3.4 to 98.7 months), the 3-year overall survival (OS) and disease-free survival (DFS) rates were 83.2% and 77.5%, respectively. In univariate analysis, patients with a higher nodal pre-treatment $SUV_{max}$ (${\geq}13.4$) demonstrated significantly lower 3-year OS (93.1% vs. 55.5%; p = 0.003), DFS (92.7% vs. 38.5%; p < 0.001), locoregional recurrence-free survival (100% vs. 50.5%; p < 0.001), and distant metastasis-free survival (100% vs. 69.2%; p = 0.004), respectively. In multivariate analysis, high pre-treatment nodal $SUV_{max}$ (${\geq}13.4$) was a negative prognostic factor for OS (hazard ratio [HR], 7.799; 95% confidence interval [CI], 1.506-40.397; p = 0.014) and DFS (HR, 9.392; 95% CI, 1.989-44.339; p = 0.005). Conclusions: High pre-treatment nodal $SUV_{max}$ was an independent prognosticator of survival and disease progression in nasopharyngeal carcinoma patients treated with IMRT in our cohort. Therefore, nodal $SUV_{max}$ may provide important information for identifying patients who require more aggressive treatment.

Effectiveness and feasibility of concurrent chemoradiotherapy using simultaneous integrated boost-intensity modulated radiotherapy with and without induction chemotherapy for locally advanced pancreatic cancer

  • Oh, Eun Sang;Kim, Tae Hyun;Woo, Sang Myung;Lee, Woo Jin;Lee, Ju Hee;Youn, Sang Hee;Han, Sung Sik;Park, Sang Jae;Kim, Dae Yong
    • Radiation Oncology Journal
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    • v.36 no.3
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    • pp.200-209
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    • 2018
  • Purpose: To evaluate the effectiveness and feasibility of chemoradiotherapy (CRT) using simultaneous integrated boost-intensity modulated radiotherapy (SIB-IMRT) in locally advanced pancreatic cancer (LAPC) patients. Materials and Methods: Between January 2011 and May 2015, 47 LAPC patients received CRT using SIB-IMRT. Prior to SIB-IMRT, 37 patients (78.7%) received induction chemotherapy (IC-CRT group) and remaining 10 patients (21.3%) did not received induction chemotherapy (CRT group). During SIB-IMRT, all patients received concomitant chemotherapy, with gemcitabine (n = 37) and capecitabine (n = 10). Results: At the time of analysis, 45 patients had died and 2 patients remained alive and the median follow-up time was 14.2 months (range, 3.3 to 51.4 months). For all patients, the median times of local progression-free survival (LPFS), progression-free survival (PFS), and overall survival (OS) were 18.1, 10.3, and 14.2 months, respectively. The median time of LPFS between IC-CRT and CRT groups was similar (18.1 months vs. 18.3 months, p = 0.711). IC-CRT group had a higher trend in PFS (10.9 months vs. 4.1 months, p = 0.054) and had significantly higher OS (15.4 months vs. 9.5 months, p = 0.007) than CRT group. In multivariate analysis, the use of induction chemotherapy and tumor response were significant factors associated with OS (p < 0.05, each). During SIB-IMRT, toxicity of grade ≥3 was observed in 7 patients (14.9%) in all patients. Conclusions: CRT using SIB-IMRT is feasible and promising in LAPC patients.

Hemorrhargic Effusion Caused by Chronic Torsion of Right Middle Lung Lobe with Concurrent Ovarian Tumor in a Female Miniature Poodle Dog (난소종양이 병발한 암컷 푸들에서 오른쪽 중간엽 폐염전으로 인한 만성적인 출혈성 흉수 증례)

  • Kim, Tae-Hwan;Hong, Subin;Kim, Minkyung;Shin, Jeong-In;Jang, Yun-Sul;Lee, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.32 no.6
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    • pp.530-535
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    • 2015
  • An 11-year-old intact female miniature poodle presented with a four-month history of hemorrhagic effusion. The patient was alert on physical examination, although muffled heart sounds were noted upon auscultation of the right hemithorax. The radiographic finding was pleural effusion. Ultrasonography revealed cystic changes in both ovaries and several nodules in the liver. A refractory opacity in the right lung field, as visualized with computer tomography (CT), was diagnosed as right middle lung lobe torsion with a collapsed bronchus. Five days after diagnosis, a right fifth intercostal thoracotomy was performed to remove the right middle lung lobe; the right middle lung lobe was grossly shrunken as a result of chronic lung lobe torsion. Ovariohysterectomy was also performed. Histopathologic examination revealed papillary adenocarcinoma in both ovaries and suspected metastasized ovarian adenocarcinoma cells in the lung lobe. The patient recovered favorably and had been doing well up to two months post-surgery. However, after four months, the dog presented with respiratory difficulty. The radiographic findings were pleural effusion and collapse of the right cranial and left caudal lung lobes. Malignant cells of epithelial origin were observed in the pleural effusion. The tumor cells were suspected to be metastasized cells from the previously resected lung lobe. Although cancer treatment was recommended, the suggestion was suspended and the dog was discharged from hospital. This was a case of lung lobe torsion that had occurred because of hemorrhagic effusion due to tumor. Although ovariohysterectomy and lobectomy were performed, there was a relapse of hemorrhagic effusion because of metastasized tumor from the previously resected lung lobe.

Capnographic Monitoring of End-Tidal Partial Pressure of Carbon Dioxide in Anesthetized Cinereous vultures (Aegypius monachus) (독수리(Aegypius monachus)의 흡입마취에서 Capnography를 이용한 호기말 이산화탄소분압 모니터링)

  • Park, Won-Kyu;Seok, Seong-Hoon;Park, Se-Jin;Lee, Seung-Yong;Kim, Young-Ki;Hwang, Jae-Min;Jeong, Dong-Hyuk;Lee, Hee-Chun;Yeon, Seong-Chan
    • Journal of Veterinary Clinics
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    • v.32 no.4
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    • pp.380-384
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    • 2015
  • The relationships between end-tidal partial pressure of carbon dioxide ($P_{ET}CO_2$) and arterial partial pressure of carbon dioxide ($P_aCO_2$), and between $P_{ET}CO_2$ and blood pH in isoflurane-anesthetized cinereous vultures were evaluated. Nine cinereous vultures (weighing 7.3-9.5 kg) were anesthetized via mask with isoflurane, intubated, and connected to a mechanical ventilator. By mechanical ventilator, respiratory rate was altered to achieve a $P_{ET}CO_2$ randomly selected among 30 to 35 mmHg. $P_aCO_2$ and blood pH were determined in serial arterial samples and compared with concurrent $P_{ET}CO_2$ measured with a sidestream capnography. Thirty six samples, nine cinereous vultures were tested 4 times each, were used to determine correlations coefficients between $P_aCO_2$ and $P_{ET}CO_2$, and between $P_{ET}CO_2$ and blood pH. Strong correlations were observed between $P_aCO_2$ and $P_{ET}CO_2$ (r = 0.951, P = 0.000, y = 1.679x - 30.236, $R^2=0.905$) as well as between $P_{ET}CO_2$ and blood pH (r = -0.728, P = 0.000, y = -0.024x + 8.389, $R^2=0.530$) with Pearson's correlation coefficient and simple linear regression. These results suggest that the capnography used provided a sufficiently accurate estimation of $P_aCO_2$ and blood pH. Thus, the monitoring of $P_{ET}CO_2$ can be useful method to prevent hypoventilation for cinereous vultures receiving mechanical ventilation.

The Effects of Lygodium japonicum Treatment on Hematological and Cyto-pathological Alterations in Non-Bacterial Prostatitis Rat Model (해금사가 만성 비세균성 전립선엽 모델에서 혈액학적 및 세포조직학적 변화에 미치는 영향)

  • Lee, Byung-Cheol;Kim, Sang-Woo;Ahn, Young-Min;Doo, Ho-Kyung;Ahn, Se-Young
    • The Journal of Internal Korean Medicine
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    • v.27 no.3
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    • pp.664-676
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    • 2006
  • Objective : Although chronic non-bacterial prostatitis is a common disease, it is very difficult to treat effectively. Lygodium japonicum has been traditionally used in treatment of urinary tract inflammation and voiding disturbance. In this study, we investigated the therapeutic effects and action mechanism of Lygodium japonicum in the rat model of non-bacterial prostatitis induced by castration and testosterone treatment. Methods : Five-month-old rats were treated with 17$\beta$-estradiol after castration for induction of experimental non-bacterial prostatitis, which is similar to human chronic prostatitis in histopathological profiles. Lygodium japonicum and testosterone were administered as an experimental specimen and a positive control. respectively. The prostates were evaluated by histopathological parameters including the epithelial score and epithelio-stromal ratio for glandular damage. PCNA labeling index for cyto-proliferation and a TUNEL(deoxyuridine triphosphate biotin nick end-labeling) assay for cell apoptosis. Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation, the rats treated with Lygodium japonicum showed a diminished range of tissue damage. Epithelial score was improved in the Lygodium japonicum group over that of the control (P<0.05). The epithelio-stromal ratio was lower in the Lygodiutn japonicum group when compared to that of the control (P<0.05). Although there was no difference in PCNA and TUNEL positive cells of the glandular epithelia. we found an decreased number of PCNA positive cell and concurrent increase of TUNEL positive cells in the stroma of Lygodium japonicum treated rats (P<0.01). Conclusions : These findings suggest that Lygodium japonicum may protect the glandular epithelial cells and also inhibit stromal proliferation in association with suppression of cyto-proliferation and stimulation of apoptosis. We concluded that Lygodium japonicum could be a useful remedy agents for treating chronic non-bacterial prostatitis.

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Association between vitamin D deficiency and anemia among Korean adolescent girls and young women (여자 청소년 및 젊은 여성의 비타민 D 결핍과 빈혈과의 연관성 분석)

  • Jang, Haeun;Park, Seonghee;Park, Kyong
    • Journal of Nutrition and Health
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    • v.52 no.6
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    • pp.552-558
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    • 2019
  • Purpose: Although vitamin D deficiency is common among Korean adolescent girls and young women, few studies have explored the potential health effects of vitamin D deficiency in this vulnerable population. This study examined the association between vitamin D deficiency and anemia in Korean adolescent girls and young women. Methods: The data from the Korea National Health and Nutrition Examination Survey 2008 ~ 2014 were used. A total of 3,643 girls and adult women aged 12 to 29 who provided all the information (including serum 25-hydroxy vitamin D, hemoglobin, and/or serum ferritin) needed for the analysis were included in the analysis. Demographic, lifestyle, and health data were obtained through survey questionnaires. Anemia and iron deficiency anemia were defined according to the World Health Organization cut-offs. Multivariable logistic regression, and restricted cubic spline regression were used in the analysis. Results: In fully adjusted logistic regression models, the vitamin D deficiency was significantly associated with higher prevalences of anemia (odds ratio (OR): 1.61, 95% confidence interval (CI): 1.04 ~ 2.49) and iron deficiency anemia (OR: 1.43, 95% CI: 1.01 ~ 2.03). In a cubic spline regression model, we observed a dose-response relationship between serum 25(OH)D concentration and anemia, and this linear relationship was also clearly observed between serum 25(OH)D concentration and iron deficiency anemia. Conclusion: Vitamin D deficiency may be associated with a higher prevalence of iron deficiency anemia and anemia in adolescent girls and young women. Alternatively, vitamin D deficiency may be a concurrent event for patients with anemia, which we cannot distinguish in this cross-sectional study. Further studies are needed to verify the causality in this population of low vitamin D levels.