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A Study on the Characteristics of the Earth Heat Extraction Using Termosyphon (Termosyphon의 지열채열 성능에 관한 고찰)

  • Shin, H.J.;Seo, J.Y.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.3
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    • pp.226-233
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    • 1993
  • Thermosyphons are simple devices that can passively transport thermal energy over relatively large distance with little temperature degradation. Especially, the thermosyphon system requires no costly energy input and is completely maintenance free. These attributes permit the use of low grade thermal energy for thermal control of structures including the stabilization of highway foundations. This paper presents the experimental results of the snow melting system in which thermosyphon was utilized to ransfer the earth energy to the pavement to remove snow and ice. The test facility, three earth heated and one unheated test panels, is designed to investigate the variables associated with removing snow and ice from pavement surfaces. The results of these test show that the earth heated panel surface temperature is higher $2{\sim}6^{\circ}C$ than unheated panel when the ambient air temperature is $-7^{\circ}C$. The thermal performance of this earth source thermosyphon system for road heating showed that there was no snow on the heated test panels when the snowfall was 5cm average for the region.

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Postoperative radiotherapy for ependymoma

  • Jung, Jinhong;Choi, Wonsik;Ahn, Seung Do;Park, Jin Hong;Kim, Su Ssan;Kim, Young Seok;Yoon, Sang Min;Song, Si Yeol;Lee, Sang-Wook;Kim, Jong Hoon;Choi, Eun Kyung
    • Radiation Oncology Journal
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    • v.30 no.4
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    • pp.158-164
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    • 2012
  • Purpose: To evaluated the patterns of failure, survival rate, treatment-related toxicity and prognostic factors in postoperative radiotherapy of patients with ependymoma. Materials and Methods: Thirty patients who underwent surgery and postoperative radiotherapy for ependymoma between the period of June 1994 and June 2008 were reviewed retrospectively. The age of patients ranged from 21 months to 66 years (median, 19 years). Seventeen patients had grade II ependymoma, and 13 had grade III anaplastic ependymoma according to the World Health Organization grading system. The postoperative irradiation was performed with 4 or 6 MV photon beam with median dose of 52.8 Gy (range, 45 to 63 Gy), and radiation field including 2 cm beyond the preoperative tumor volume. Median follow-up period was 51 months (range, 12 to 172 months). Results: Fourteen out of 30 (46.7%) patients experienced recurrence, and 12 of those died. Among those 14 patients who experienced recurrence, 11 were in-field and 3 were out-of-field recurrence. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 66.7% and 56.1%, respectively. On univariate analysis, tumor grade was a statistically significant prognostic factor for OS and PFS. There were two complications after surgery and postoperative radiotherapy, including short stature and facial palsy on the left side. Conclusion: We observed good survival rates, and histologic grade was a prognostic factor affecting the OS and PFS. Almost all recurrence occurred in primary tumor site, thus we suggest further evaluation on intensity-modulated radiotherapy or stereotatic radiosurgery for high-risk patients such as who have anaplastic ependymoma.

Comparison of Concurrent Chemoradiotherapy Followed by Adjuvant Chemotherapy Versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma: a Meta-analysis of 793 Patients from 5 Randomized Controlled Trials

  • Liang, Zhong-Guo;Zhu, Xiao-Dong;Zhou, Zhi-Rui;Qu, Song;Du, You-Qin;Jiang, Yan-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5747-5752
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    • 2012
  • Purpose: The main objective of the present study was to evaluate the efficacy and toxicity of concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone in the treatment of locoregionally advanced nasopharyngeal carcinoma. Methods: The search strategy included Pubmed, Embase, the Cochrane Library, China National Knowledge Internet Web, Chinese Biomedical Database and Wanfang Database. We also searched reference lists of articles and the volumes of abstracts of scientific meetings. Randomized controlled trials (RCTs) that compared concurrent chemoradiotherapy followed by adjuvant chemotherapy with concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma were included. Meta-analysis was performed with RevMan 5.1.0. The Grading of Recommendations Assessment, Development, and Evaluation system (GRADE) was used to rate the level of evidence. Results: Five studies were included. Risk ratios of 1.02 (95%CI 0.89-1.15), 0.93 (95%CI 0.72-1.21), 1.07 (95%CI 0.87-1.32), 0.95 (95%CI 0.80-1.13) were observed for 3 years overall survival, 5 years failure-free survival, 5 years locoregional failure-free survival and 5 years distant metastasis failure-free survival. There were no treatment-related deaths in both groups of five studies. Hematologic and gastrointestinal toxicity were the most significant for patients during adjuvant chemotherapy. The level of evidence was low. Conclusion: Compared with concurrent chemoradiotherapy alone, concurrent chemotherapy followed by adjuvant chemotherapy did not improve prognosis. More toxicity was found during adjuvant chemotherapy.

Changes of the Chemical and Microbiological Quality in Milk from Jeju-Do after Raw Milk Grading System (등급제 실시 이후 제주산 원유의 품질 변화)

  • Lee, Hyun-Jong
    • Journal of Dairy Science and Biotechnology
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    • v.24 no.1
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    • pp.1-7
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    • 2006
  • This experiment was performed to identify the improvement of raw milk quality after introducing raw milk grading system(1993, June). The purpose of this experiment was to investigate chemical component and microbiological quality of raw milk in jeju. This experiment made it possible to spread high standard of quality of raw milk or milk product including yoghurt, ice cream etc., and to provide dairy industry information for the construction of Jeju international free city master plan. As a result, automatic milking system is improved a lot after introducing raw milk grading system and sustained good condition compared with other provinces. High ratio was shown dairy farm in jeju for pre-milking, pre-cooling system equipment and self laboring. Otherwise, the ratio of dairy farm doing test of mastitis is low. The ratio of first grade distribution in Jeju is 80.64%, which means that was improved before introducing raw milk grading system. The number of somatic cells found in summer more than that of other seasons in raw milk. However, these data is a little higher than the nation wide data medium. Also, general components, annual lipid ratio is 3.90% that improved compared with before introducing raw milk grading system. These data showed low in summer and similar to nation wide.

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Prognostic Significance of Altered Blood and Tissue Glutathione Levels in Head and Neck Squamous Cell Carcinoma Cases

  • Khan, Sami Ullah;Mahjabeen, Ishrat;Malik, Faraz Arshad;Kayani, Mahmood Akhtar
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7603-7609
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    • 2014
  • Glutathione is a thiol compound that plays an important role in the antioxidant defense system of the cell and its deficiency leads to an increased susceptibility to oxidative stress and, thus, progression of many disease states including head and neck cancer. In the present study, alterations of glutathione levels were investigated in study cohort of 500 samples (cohort 1 containing 200 head and neck cancer blood samples along with 200 healthy controls and cohort II with 50 head and neck squamous cell carcinoma tissue samples along with 50 control tissues) by high performance liquid chromatography. The results indicated that mean blood glutathione levels were significantly reduced in head and neck cancer patients (p<0.001) compared to respective controls. In contrast, the levels of glutathione total (p<0.05) and glutathione reduced (p<0.05) were significantly elevated in head and neck squamous cell carcinoma tissues compared to the adjacent cancer-free control tissues. In addition to this, pearson correlation performed to correlate different tissue glutathione levels (GSH) with clinical/pathological parameters demonstrated a significant negative correlation between pT-stage and GSH level ($r=-0.263^{**}$; p<0.01), C-stage and GSH level ($r=-0.335^{**}$; p<0.01), grade and GSH ($r=-0.329^{**}$; p<0.01) and grade versus redox index ($r=-0.213^{**}$; p<0.01) in HNSCC tissues. Our study suggests that dysregulation of glutathione levels in head and neck cancer has the potential to predict metastasis, and may serve as a prognostic marker.

Role of Postoperative Radiotherapy for Patients with Pathological Stage III Non-Small-Cell Lung Cancer after Curative Resection (근치적 절제술 후 병기3의 비소세포성 폐암에서 수술 후 방사선 치료의 역할)

  • Kim, Mi-Young;Wu, Hong-Gyun;Kim, Hak-Jae;Heo, Dae-Seog;Kim, Young-Whan;Kim, Dong-Wan;Lee, Se-Hoon;Kim, Joo-Hyun;Kim, Young-Tae;Kang, Chang-Hyun
    • Radiation Oncology Journal
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    • v.29 no.1
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    • pp.44-52
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    • 2011
  • Purpose: To evaluate the outcomes and prognostic factors of postoperative radiotherapy (PORT) for patients with pathological stage III non-small-cell lung cancer (NSCLC) at a single institution. Materials and Methods: From 2000 to 2007, 88 patients diagnosed as having pathologic stage III NSCLC after curative resection were treated with PORT. There were 80 patients with pathologic stage IIIA and eight patients with pathologic stage IIIB in the AJCC 6th staging system. The majority of patients (n=83) had pathologic N2 disease, and 56 patients had single station mediastinal LN metastasis. PORT was administered using conventional technique (n=76) or three-dimensional conformal technique (n=12). The median radiation dose was 54 Gy (range, 30.6 to 63 Gy). Thirty-six patients received chemotherapy. Radiation pneumonitis was graded by the Radiation Therapy Oncology Group system, and other treatment-related toxicities were assessed by CTCAE v 3.0. Results: Median survival was 54 months (range, 26 to 77 months). The 5-year overall survival (OS) and disease free survival (DFS) rates were 45% and 38%, respectively. The number of metastatic lymph nodes was associated with overall survival (hazard ratio, 1.037; p-value=0.040). The 5-year locoregional recurrence free survival (LRFS) and distant metastasis free survival (DMFS) rates were 88% and 48%, respectively. Multiple stations of mediastinal lymph node metastasis was associated with decreased DFS and DMFS rates (p-value=0.0014 and 0.0044, respectively). Fifty-one relapses occurred at the following sites: 10 loco-regional, 41 distant metastasis. Grade 2 radiation pneumonitis was seen in three patients, and symptoms were well tolerated with anti-tussive medication. Grade 2 radiation esophagitis was seen in 11 patients. There were no grade 3 or more severe complications associated with PORT. Conclusion: Our retrospective data show that PORT for pathological stage III NSCLC is a safe and feasible treatment and could improve loco-regional control. The number of metastatic lymph nodes and stations of mediastinal lymph node metastasis were analyzed as prognostic factors. Furthermore, efforts are needed to reduce distant metastasis, which is a major failure pattern of advanced stage NSCLC.

Low energy ultrasonic single beacon localization for testing of scaled model vehicle

  • Dubey, Awanish C.;Subramanian, V. Anantha;Kumar, V. Jagadeesh
    • Ocean Systems Engineering
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    • v.9 no.4
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    • pp.391-407
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    • 2019
  • Tracking the location (position) of a surface or underwater marine vehicle is important as part of guidance and navigation. While the Global Positioning System (GPS) works well in an open sea environment but its use is limited whenever testing scaled-down models of such vehicles in the laboratory environment. This paper presents the design, development and implementation of a low energy ultrasonic augmented single beacon-based localization technique suitable for such requirements. The strategy consists of applying Extended Kalman Filter (EKF) to achieve location tracking from basic dynamic distance measurements of the moving model from a fixed beacon, while on-board motion sensor measures heading angle and velocity. Iterative application of the Extended Kalman Filter yields x and y co-ordinate positions of the moving model. Tests performed on a free-running ship model in a wave basin facility of dimension 30 m by 30 m by 3 m water depth validate the proposed model. The test results show quick convergence with an error of few centimeters in the estimated position of the ship model. The proposed technique has application in the real field scenario by replacing the ultrasonic sensor with industrial grade long range acoustic modem. As compared with the existing systems such as LBL, SBL, USBL and others localization techniques, the proposed technique can save deployment cost and also cut the cost on number of acoustic modems involved.

Preliminary Results of Concurrent Chemotherapy and Radiation Therapy using High-dose-rate Brachytherapy for Cervical Cancer (자궁경부암에 항암화학요법과 동시 병용요법으로 외부 방사선조사와 고선량률 강내조사의 예비적 치료 결과)

  • Lee, Kyung-Ja;Lee, Ji-Hye;Lee, Re-Na;Suh, Hyun-Suk
    • Radiation Oncology Journal
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    • v.24 no.3
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    • pp.171-178
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    • 2006
  • [ $\underline{Purpose}$ ]: To determine the efficacy and safety of concurrent chemotherapy and radiation therapy with high-dose-rate brachytherapy for cervical cancer. $\underline{Materials\;and\;Methods}$: From January 2001 to December 2002, 30 patients with cervical cancer were treated with concurrent chemotherapy (cisplatin and 5-FU) and definitive radiation therapy. The median age was 58 (range $34{\sim}74$) year old. The pathology of the biopsy sections was squamous cell carcinoma in 29 patients and one was adenocarcinoma. The distribution to FIGO staging system was as follows: stage IB, 7 (23%); IIA, 3 (10%); IIB, 12 (40%); IIIA, 3 (10%); IIIB, 5 (17%). All patients received pelvic external beam irradiation (EBRT) to a total dose of $45{\sim}50.4\;Gy$ (median: 50.4 Gy) over $5{\sim}5.5$ weeks. Ir-192 HDR intracavitary brachytherapy (ICBT) was given after a total dose of 41.4 Gy. HDR-ICBT was performed twice a week, with a fraction point A dose of 4 Gy and median dose to point A was 28 Gy (range: $16{\sim}32\;Gy$) in 7 fractions. The median cumulative biologic effective dose (BED) at point A (EBRT+ICBT) was $88\;Gy_{10}$ (range: $77{\sim}94\;Gy_{10}$). The median cumulative BED at ICRU 38 reference point (EBRT+ICBT) was $131\;Gy_3$ (range: $122{\sim}140\;Gy_3$) at point A, $109\;Gy_3$ (range: $88{\sim}125\;Gy_3$) at the rectum and $111\;Gy_3$ (range: $91{\sim}123\;Gy_3$) at the urinary bladder. Cisplatin ($60\;mg/m^2$) and 5-FU ($1,000\;mg/m^2$) was administered intravenously at 3 weeks interval from the first day of radiation for median 5 (range: $2{\sim}6$) cycles. The assessment was performed at 1 month after completion of radiation therapy by clinical examination and CT scan. The median follow-up time was 36 months (range: $8{\sim}50$ months). $\underline{: The complete response rate after concurrent chemoradiation therapy was 93.3%. The 3-yr actuarial pelvic control rate was 87% and 3-yr actuarial overall survival and disease-free survival rate was 93% and 87%, respectively. The local failure rate was 13% and distant metastatic rate was 3.3%. The crude rate of minor hematologic complications (RTOG grade 1-2) occurred in 3 patients (10%) and one patient had suffered from severe leukopenia (RTOG grade 4) during concurrent treatment. Acute minor enterocolitis (RTOG grade 1-2) occurred in 11 patients (37%) and one patient (3%) was suffered from colon perforation during radiation therapy. Late colitis of RTOG grade 1 occurred in 5 patients (15%). Acute cystitis of RTOG grade 1 occurred in 12 patients (40%) and late cystitis of RTOG grade 2 occurred in one patient (3%). No treatment related death was seen. $\underline{Conclusion}$: The results of this study suggest that the concurrent chemoradiation therapy with HDR brachytherapy could be accepted as an effective and safe treatment for cervical cancer.

Fatigue evaluation and CFRP strengthening of diaphragm cutouts in orthotropic steel decks

  • Ke, Lu;Li, Chuanxi;He, Jun;Lu, Yongjun;Jiao, Yang;Liu, Yongming
    • Steel and Composite Structures
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    • v.39 no.4
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    • pp.453-469
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    • 2021
  • The cracking at the transverse diaphragm cutout is one of the most severe fatigue failures threatening orthotropic steel decks (OSDs), whose mechanisms and crack treatment techniques have not been fully studied. In this paper, full-scale experiments were first performed to investigate the fatigue performance of polished cutouts involving the effect of an artificial geometrical defect. Following this, comparative experimental testing for defective cutouts strengthened with carbon fiber-reinforced polymer (CFRP) was carried out. Numerical finite element analysis was also performed to verify and explain the experimental observations. Results show that the combinative effect of the wheel load and thermal residual stress constitutes the external driving force for the fatigue cracking of the cutout. Initial geometrical defects are confirmed as a critical factor affecting the fatigue cracking. The principal stress 6 mm away from the free edge of the cutout can be adopted as the nominal stress of the cutout during fatigue evaluation, and the fatigue resistance of polished cutouts is higher than Grade A in AASHTO specification. The bonded CFRP system is highly effective in extending the fatigue life of the defective cutouts. The present study provides some new insights into the fatigue evaluation and repair of OSDs.

A Study on the Thermal Characteristics of the Large Low Temperature Vacuum Dryer for Biological Drying (생체 건조용 대형 저온진공건조기의 열적 특성에 관한 연구)

  • 김경근;성부용;정한식;최순열;문수범
    • Journal of Advanced Marine Engineering and Technology
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    • v.24 no.4
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    • pp.427-434
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    • 2000
  • In tradition, there have been two kinds of drying methods, which are sun drying and artificial drying. The sun drying method which has been adopted traditionally has been replaced by the hot-air drying method which is one of the most general methods of artificial drying, with its simple drying system, low initial cost of drying plant, and easy operating method. But the hot-air drying method has some defects; (1) much energy loss happens due to the discharge of hot air during the drying process, (2) control of drying rate is not easy on account of changing relative humidity of inlet air for uniform hot air temperature, (3) high temperature of foods in drying process brings about the production of low-grade drying products. Vacuum drying takes advantage of energy saving and mass production because it reduces the drying time by increasing the drying rate under low temperature condition. The aim of this paper is to develop the low temperature vacum dryer, with low initial investments and operating costs, easy operating method and trouble-free operation.

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