• Title/Summary/Keyword: local mass

Search Result 1,240, Processing Time 0.024 seconds

Conceptual Design of a Riser for 10 MW OTEC (10MW급 해양온도차발전을 위한 라이저 개념설계)

  • Jung, Dongho;Kwon, Yongju;Kim, Hyeonju
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.18 no.1
    • /
    • pp.29-35
    • /
    • 2015
  • The concept design of a riser for Ocean Thermal Energy Conversion in 10 MW is proposed and its dynamic behaviour characteristics is analyzed with numerical method. A riser pipe with a hollow along its thickness in the cross-section to increase the effective modulus of its cross-section is designed considering the manufacture. The riser pipe without hollows along its thickness needs a lumped weight at the bottom end of a riser in order to keep its vertical hanging configuration from large buoyancy and the strong current. The riser is designed to control its density by inserting materials in high or low density into a hollow. The dynamic behaviour characteristics of the two designed risers is evaluated with the developed numerical analysis tool. The combined stress of the riser with a lumped weight is showed to be dominated by weight of a lumped mass. The riser with no hollow shows large combined stress near sea surface by strong current. Local structural analysis for the cross-section of a hollow riser is needed in detail.

Effect of surgical site instillation after laparoscopic urologic surgery (비뇨기과 복강경 수술 후 국소마취제 점적의 효과)

  • Hwang, Yong;Shin, Sangyol;Oh, Tae Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.7
    • /
    • pp.200-206
    • /
    • 2018
  • The aim of this study was to evaluate the effect of Ropivacaine on pain following laparoscopic surgery. Between March 2015 and June 2017, all 97 patients with renal mass who elected to receive laparoscopic nephrectomy were reviewed, retrospectively. Normal saline (0.9%) was used as a control in 45 patients while Ropivacaine was used for local anesthesia in the instillation group (n=52). Pain score (visual analog scale) of the shoulder and upper abdominal area between the two groups was significantly different between recovery time and 24 h (p<0.05), with no significant differences between 48 and 72 h (both p>0.05). In the instillation group, pain score of shoulder and abdominal pain in the two groups according to the amount of CO2 used was not significantly different between recovery time and 24, 48, and 72 h (all p>0.05). Ropivacaine reduced shoulder and upper abdominal pain that occurred within 24 h after surgery. Effective pain control with Ropivacaine is needed in the early postoperative period when a large amount of CO2 is used in laparoscopic surgery.

Experimental study on applicability of Air-Curtain system in train fire at subsea tunnel rescue station (해저터널 열차 화재 시 구난역 에어커튼 시스템의 성능에 관한 실험 연구)

  • Park, Byoung-Jik;Shin, Hyun-Jun;Yoo, Yong-Ho;Park, Jin-Ouk;Kim, Hwi-Seong;Kim, Yang-Kyun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.20 no.1
    • /
    • pp.1-9
    • /
    • 2018
  • Visibility is very poor in tunnel fire because of confined space where the fire may easily lead to the mass casuality incident because of fast smoke spread. In this test, air curtain and the fan were installed at rescue station in a bid to make use of rescue station in safe way during the train fire in undersea tunnel and a full-scale fire test was conducted to identify the applicability of air curtain system. Air curtain system was installed at a real rescue station and the test was continued for 2 minutes till heptane which was used as fire source was completely burned out. When air curtain was working, difference in temperature between inside and outside the platform was $160^{\circ}C$ and carbon monoxide measured inside the platform was less than the case of no air curtain system by 160 ppm. Thus a full-scale fire test demonstrated that the air curtain system installed at rescue station in undersea tunnel was able to effectively block the heat and smoke generated from the fire.

Young Women with Breast Cancer in the United States and South Korea: Comparison of Demographics, Pathology and Management

  • Son, Byung Ho;Dominici, Laura S;Aydogan, Fatih;Shulman, Lawrence N;Ahn, Sei Hyn;Cho, Ja Young;Coopey, Suzanne B;Kim, Sung Bae;Min, H Elise;Valero, Monica;Wang, Jiping;Caragacianu, Diana;Gong, Gyung-yub;Hevelone, Nathanael D;Baek, Seunghee;Golshan, Mehra
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.6
    • /
    • pp.2531-2535
    • /
    • 2015
  • Background: Breast cancer diagnosed in young women may be more aggressive, with higher rates of local and distant recurrence compared to the disease in older women. Epidemiologic evidence suggests that Korean women have a lower incidence of breast cancer than women in the United States, but that they present at a younger age than their American counterparts. We sought to compare risk factors and management of young women with breast cancer in Boston, Massachusetts (US) with those in Seoul, South Korea (KR). Materials and Methods: A retrospective review was performed of consecutive patients less than 35 years old with a diagnosis of breast cancer at academic cancer centers in the US and KR from 2000-2005. Patient data were obtained by chart review. Demographic, tumor and treatment characteristics were compared utilizing Pearson's chisquare or Wilcoxon rank-sum tests where appropriate. All differences were assessed as significant at the 0.05 level. Results: 205 patients from the US and 309 from KR were analyzed. Patients in US were more likely to have hormone receptor positive breast cancer, while patients in KR had a higher rate of triple negative lesions. Patients in US had a higher mean body mass index and more often reported use of birth control pills, while those in the KR were less likely to have a sentinel node procedure performed or to receive post mastectomy radiation. Conclusions: Patients under 35 diagnosed with breast cancer in the US and KR differ with respect to demographics, tumor characteristics and management. Although rates of breast conservation and mastectomy were similar, US patients were more likely to receive post mastectomy radiation. The lower use of sentinel node biopsy is explained by the later adoption of the technique in KR. Further evaluation is necessary to evaluate recurrence rates and survival in the setting of differing disease subtypes in these patients.

Size Distributions of Trace Elements in Airborn Particulates Collected using Drum impactor at Gosan, Jeju Island : Measurements in Springtime 2002 (DRUM impactor를 이용한 대기 입자상 물질 중 원소성분의 입경분포 특성 : 제주도 고산지역의 2002년 봄철 (3.29-5.30) 측정 연구)

  • 한진석;문광주;류성윤;안준영;공부주;홍유덕;김영준
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.20 no.4
    • /
    • pp.555-569
    • /
    • 2004
  • Size -segregated measurements of aerosol composition using 8-stage DRUM impactor are used to determine the transport of natural and anthropogenic aerosols at Gosan site from 29 March to 30 May in 2002. Separation of ambient aerosols by DRUM impactor offers many Advantages over other standard filtration techniques. Some of the most important advantages are the ability to segregate into details by particle tire, to better preserve chemical integrity since the air stream doesn't pars through the deposit, to collect samples as a function of time, and to have a wide variety of impaction surfaces available to match analytical needs. Although the transport of Yellow sand is a well-known phenomenon in springtime, the result of measurement shows that not only soil dust but also anthropogenic aerosols, including sulfur, enriched trace metals such as Pb, Ni, Zn. Cu, Cr, As, Se, Br, are transported to Gosan in springtime. This study combines the size- and time-resolved aerosol composition measurements with isentropic, backward air-mass trajectories in order to identify some potential source regions of anthropogenic aerosols. As a result, during the NYS period, the average concentration of PM$_{10}$ was 46$\mu\textrm{g}$/㎥, Si, Al. S, Fe, Cl, K, Ca were higher than 1,000 ng/㎥ and Ti was about 100 ng/㎥. The concentrations of Zn, Mn, Cu. Pb, Br, Rb, V, Cr, Ni. At, Se ranged between 1 and 70 ng/㎥. More than 50% typical soil elements, tuck as Al, Si, Fe, Cd. Ti, Cr, Cu, Br. were distributed in a coarse particle range(5.0-12${\mu}{\textrm}{m}$). In other hand, anthropogenic pollutants, luck as S, N, Vi, were mainly distributed in a fine particle range (0.09-0.56${\mu}{\textrm}{m}$). During the YS period, PM$_{10}$ increased about 8 times than NYS period, and main soil elements, such as Al, Si, S, K, V, Mn, Fe also doubled in coarse particle range (1.15-12${\mu}{\textrm}{m}$). But Zn, As, Pb, Cu and Se, which distributed in the time aerosols (0.09-0.56${\mu}{\textrm}{m}$), were on the same level with or decreased than NYS period. Finally. except the YS Period, coarse particles (2.5-12${\mu}{\textrm}{m}$) are inferred to be influenced by soil, coal combustion, waste incineration, ferrous and nonferrous sources through similar pathways with Yellow Sand. But fine particles have different sources, such as coal combustion, gasoline vehicle, biomass burning, oil or coal combustion, nonferrous and ferrous metal sources, which are transported from China, Korea peninsula and local sources.ces.

Precambrian Crustal Evolution of the Korean Peninsula (한반도 선캠브리아 지각진화사)

  • Lee, Seung-Ryeol;Cho, Kyung-O
    • The Journal of the Petrological Society of Korea
    • /
    • v.21 no.2
    • /
    • pp.89-112
    • /
    • 2012
  • The Korean Peninsula consists of three Precambrian blocks: Nangrim, Gyeonggi and Yeongnam massifs. Here we revisited previous stratigraphic relationships, largely based on new geochronologic data, and investigated the crustal evolution history of the Precambrian massifs. The Precambrian strata have been usually divided into lower crystalline basements and upper supracrustal rocks. The former has been considered as Archean or Paleoproterozoic in age, whereas the latter as Paleoproterozoic or later. However, both are revealed as the Paleoproterozoic (2.3-1.8 Ga) strata as a whole, and Archean strata are very limited in the Korean Peninsula. These make the previous stratigraphic system wrong and require reconsideration. The oldest age of the basement rocks can be dated as old as Paleoarchean, suggested by the occurrence of ~3.6 Ga inherited zircon. However, most of crust-forming materials were extracted from mantle around ~2.7 Ga, and produced major portions of crust materials at ~2.5 Ga, which make each massif a discrete continental mass. After that, all the massifs belonged to continental margin orogen during the Paleoproterozoic time, and experienced repeated intracrustal differentiation. After the final cratonization occurring at ~1.9-1.8 Ga, they were stabilized as continental platforms. The Nangrim and Gyeonggi massif included local sedimentary deposition as well as igneous activity during Meso-to Neoproterozoic, but the Yeongnam massif remained stable before the development of Paleozoic basin.

Prediction of dryout-type CHF for rod bundle in natural circulation loop under motion condition

  • Huang, Siyang;Tian, Wenxi;Wang, Xiaoyang;Chen, Ronghua;Yue, Nina;Xi, Mengmeng;Su, G.H.;Qiu, Suizheng
    • Nuclear Engineering and Technology
    • /
    • v.52 no.4
    • /
    • pp.721-733
    • /
    • 2020
  • In nuclear engineering, the occurrence of critical heat flux (CHF) is complicated for rod bundle, and it is much more difficult to predict the CHF when it is in natural circulation under motion condition. In this paper, the dryout-type CHF is investigated for the rod bundle in a natural circulation loop under rolling motion condition based on the coupled analysis of subchannel method, a one-dimensional system analysis method and a CHF mechanism model, namely the three-fluid model for annular flow. In order to consider the rolling effect of the natural circulation loop, the subchannel model is connected to the one-dimensional system code at the inlet and outlet of the rod bundle. The subchannel analysis provides the local thermal hydraulic parameters as input for the CHF mechanism model to calculate the occurrence of CHF. The rolling motion is modeled by additional motion forces in the momentum equation. First, the calculation methods of the natural circulation and CHF are validated by a published natural circulation experiment data and a CHF empirical correlation, respectively. Then, the CHF of the rod bundle in a natural circulation loop under both the stationary and rolling motion condition is predicted and analyzed. According to the calculation results, CHF under stationary condition is smaller than that under rolling motion condition. Besides, the CHF decreases with the increase of the rolling period and angular acceleration amplitude within the range of inlet subcooling and mass flux adopted in the current research. This paper can provide useful information for the prediction of CHF in natural circulation under motion condition, which is important for the nuclear reactor design improvement and safety analysis.

Analysis of Dietary Characteristics of Participants Attending the Nutrition Education Program for Hypertensive Patients at a Public Health Center (보건소 고혈압 영양교육 참여자의 식생활 요인 분석)

  • Im, Gyeong-Suk;Han, Mun-Hwa;Gang, Yong-Hwa;Park, Hyei-Ryeon;Kim, Chan-Ho
    • Journal of the Korean Dietetic Association
    • /
    • v.6 no.2
    • /
    • pp.125-135
    • /
    • 2000
  • Hypertension is a well-known degenerative disease whose prevalence rate increases with age. Management of high blood pressure is a critical concern in preventive strategies to reduce the morbidity and mortality for cardiovascular disease. The purpose of this study was to examine the dietary characteristics of hypertensive program participants, and to establish strategies based on their nutritional needs. Hypertensive patients were enrolled in the program in a public health center or in a local elderly center, at Suwon, in 1999-2000. Trained dietitians interviewed 62 enrollees(24-hour recall) and related variables. Mean body mass index of the subjects was 25.0kg/m². 30.7% of the subjects had a family history of hypertension. The majority of them ate regularly and partook of all available side dishes. They consumed grains and vegetables regularly, but seldom ate dairy products or food prepared with oil. Male enrollees frequently consumed more processed food and animal fat than did female enrollees(p<0.05). An analysis of the percentage of RDA(Recommended Dietary Allowances of Korea 1995) showed that but for ascorbic acid, enrollees consumed nutrients below the RDA. The food group intake pattern was not diverse, thus only 8.1% of enrollees consumed all food groups in a day. An analysis of eating attitude showed that 64.5% of enrollees always added salt to beef soup. Male enrollees showed low food-related self-efficacy compared to female enrollees, especially with reference to reduction of instant food intake(p<0.01), increase in vegetable intake(p<0.01), reduction of monosodium glutamate(MSG) intake(p<0.01). and not overeating(p<0.05). Their perceived barriers for participating in hypertension nutrition programs included lack of time, program necessity non-recognition, and program comprehension difficulty. These results suggest that nutrition education program necessity non-recognition, and program comprehension difficulty. These results suggest that nutrition education programs for community hypertensive patients should focus on increasing participant consumption of foods, expecially dairy products, and desirable eating attitudes. It also suggests that the program should consider should consider encouraging self-efficacy in changing eating behavior.

  • PDF

THE ERUPTION GUIDANCE OF AN IMPACTED TOOTH ASSOCIATED WITH A COMPLEX ODONTOMA : CASE REPORT (복잡 치아종으로 인한 매복치아의 교정적 견인)

  • Pack, Jung-Ah;Yang, Kyu-Ho;Choi, Nam-Ki;Kim, Seon-Mi
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.34 no.4
    • /
    • pp.651-657
    • /
    • 2007
  • Odontomas are the common type of odontogenic tumors and generally are asymptomatic and frequently lead to impaction or delayed eruption of permanent teeth. They are composed of enamel, dentin, cementum and pulp tissue and are divided into compound and complex according to the morphology of the hard tissues. Compound odontomas consist of varying numbers of small toothlike structure and have a predilection for the maxillary anterior regions. Complex odontomas consist of an unorganized mass of odontogenic tissues and comprise approximately 25 percent of all odontomas and have a predilection for the mandibular posterior regions. The etiology of odontomas is uncertain but hypothesized to involve local trauma, infection and genetic factors. Treatment of odontoma is conservative surgical removal and are little probability of recurrence. These two cases were about the patients with delayed eruption of mandibular first molar and mandibular lateral incisor. We surgically removed odontoma, exposed impacted tooth and guided impacted tooth into normal position by orthodontic traction. At the completion of traction, the mandibular first molar and mandibular lateral incisor was positioned fairly within the arch and complications such as root resorption were not observed.

  • PDF

Endobronchial Metastasis of Epithelioid Sarcoma

  • Kim, Seo-Yun;Lee, Ji-Yeon;Lee, Yeon-Joo;Park, Sung-Soo;Koo, Hyeon-Kyoung;Lee, Sang-Min;Yim, Jae-Joon;Yang, Seok-Chul;Yoo, Chul-Gyu;Han, Sung-Koo;Shim, Young-Soo;Kim, Young-Whan
    • Tuberculosis and Respiratory Diseases
    • /
    • v.70 no.5
    • /
    • pp.423-427
    • /
    • 2011
  • Epithelioid sarcomas are rare soft tissue sarcomas with a high tumor grade and high local recurrence and metastasis rates. Although the lung is the most common site of metastasis, endobronchial metastasis hasn't been reported yet. We now report a case of epithelioid sarcoma with endobronchial metastasis. A 28-year-old man had recurrent pneumothorax and underwent wedge resection. He presented at our hospital with hemoptysis, dyspnea, and chest pain. Chest computed tomography revealed left pneumothorax, multiple lung nodules and endobronchial lesions at the right lower basal lobe. Bronchoscopy showed a hemorrhagic mass obstructing the bronchus of the right lower basal lobe. Magnetic resonance imaging revealed multiple nodular lesions in the left thigh muscles. The bronchoscopic biopsy of the endobronchial lesion and the muscle biopsy of the thigh showed the same feature epithelioid sarcoma. This is the first case report of an epithelioid sarcoma with endobronchial metastasis that was diagnosed by bronchoscopic biopsy.