• Title/Summary/Keyword: Response Cases

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Spatially variable effects on seismic response of the cable-stayed bridges considering local soil site conditions

  • Tonyali, Zeliha;Ates, Sevket;Adanur, Suleyman
    • Structural Engineering and Mechanics
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    • v.70 no.2
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    • pp.143-152
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    • 2019
  • In this study, stochastic responses of a cable-stayed bridge subjected to the spatially varying earthquake ground motion are investigated for variable local soil cases and wave velocities. Quincy Bay-view cable-stayed bridge built on the Mississippi River in Illinois, USA selected as a numerical example. The bridge is composed of two H-shaped concrete towers, double plane fan type cables and a composite concrete-steel girder deck. The spatial variability of the ground motion is considered with the coherency function, which is represented by the components of incoherence, wave-passage and site-response effects. The incoherence effect is investigated by considering Harichandran and Vanmarcke model, the site-response effect is outlined by using hard, medium and soft soil types, and the wave-passage effect is taken into account by using 1000, 600 and 200 m/s wave velocities for the hard, medium and soft soils, respectively. Mean of maximum response values obtained from the analyses are compared with those of the specific cases of the ground motion model. It is concluded that the obtained results from the bridge model increase as the differences between local soil conditions cases of the bridge supports change from firm to soft. Moreover, the variation of the wave velocity has important effects on the responses of the deck and towers as compared with those of the travelling constant wave velocity case. In addition, the variability of the ground motions should be considered in the analysis of long span cable-stayed bridges to obtain more accurate results in calculating the bridge responses.

Exchange Rate Pass-Through, Asymmetric Responses and Market Shares (환율 변동의 비대칭적 전이와 시장점유율)

  • Tcha, MoonJoong
    • KDI Journal of Economic Policy
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    • v.27 no.1
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    • pp.185-209
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    • 2005
  • This study examines ERPT with asymmetric response and both import and export market shares, using wool trade data. The study found that, asymmetric response may be as common as symmetric response. In addition, the responses (both in price and quantity demanded) to the changes in exchange rate are considerably different across goods, and even for the homogenous goods, across countries. In case of depreciation, the export price changes more than appreciation case in general, and as a result the destination price changes less. It is also found that the cases of excessive or perverse pass-through are found more frequently than reported by previous studies. This finding points out that strategic behavior of firms or unexpected response to exchange rate fluctuation takes place more frequently than we commonly expect or take, in particular at disaggregated levels. When the model considers asymmetric responses of the export price to appreciation and depreciation (of exporter's currency), the estimation provided that for 39 trade cases out of 83, export price responded to appreciation and depreciation in different fashions, although the normal response was the dominating phenomenon with 99 cases or about 60% out of 166 cases. Market shares affected the extent and direction of responses in select cases. These findings will have important implications for policy makers and traders.

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Influence of pinching effect of exterior joints on the seismic behavior of RC frames

  • Favvata, Maria J.;Karayannis, Chris G.
    • Earthquakes and Structures
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    • v.6 no.1
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    • pp.89-110
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    • 2014
  • Nonlinear dynamic analyses are carried out to investigate the influence of the pinching hysteretic response of the exterior RC beam-column joints on the seismic behavior of multistory RC frame structures. The effect of the pinching on the local and global mechanisms of an 8-storey bare frame and an 8-storey pilotis type frame structure is evaluated. Further, an experimental data bank extracted from literature is used to acquire experimental experience of the range of the real levels that have to be considered for the pinching effect on the hysteretic response of the joints. Thus, three different cases for the hysteretic response of the joints are considered: (a) joints with strength and stiffness degradation characteristics but without pinching effect, (b) joints with strength degradation, stiffness degradation and low pinching effect and (c) joints with strength degradation, stiffness degradation and high pinching effect. For the simulation of the beam-column joints a special-purpose rotational spring element that incorporates the examined hysteretic options developed by the authors and implemented in a well-known nonlinear dynamic analysis program is employed for the analysis of the structural systems. The results of this study indicate that the effect of pinching on the local and global responses of the examined cases is not really significant at early stages of the seismic loading and especially in the cases when strength degradation in the core of exterior joint has occurred. Nevertheless in the cases when strength degradation does not occur in the joints the pinching may increase the demands for ductility and become critical for the columns at the base floor of the frame structures. Finally, as it was expected the ability for energy absorption was reduced due to pinching effect.

Study fo the Characteristics Analysis of Laboratory Chemical Accidents (실험실 화학사고 특성 분석에 관한 연구)

  • Lee, Tae-Hyung;Lee, Deok-Jae;Park, Joong-Don;Shin, Chang-Hyun
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.110-116
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    • 2016
  • The major aim of this study was to provide information on the chemical accidents that occurred in laboratories over the last 3 years. The total incidence of laboratory chemical accidents was 30 cases; 25 cases occurred at educational institutions. Most accidents (19 cases) occurred due to spills and leaks. The main cause of the accidents analyzed was worker carelessness (21 cases). Twenty-two accidents were related to hazardous chemical substances. In addition, general chemical substances as well as waste liquid contributed 26% to the incidents related to the laboratory. Among the 22 hazardous chemical substances involved in laboratory chemical accident, 67% of accident substances were accident preparedness substances.

Comparison of WHO and RECIST Criteria for Evaluation of Clinical Response to Chemotherapy in Patients with Advanced Breast Cancer

  • Khokher, Samina;Qureshi, Muhammad Usman;Chaudhry, Naseer Ahmad
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3213-3218
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    • 2012
  • When patients with advanced breast cancer (ABC) are treated with neoadjuvant chemotherapy (NACT), efficacy is monitored by the extent of tumor shrinkage. Since their publication in 1981, World Health Organization (WHO) guidelines have been widely practiced in clinical trials and oncologic practice, for standardized tumor response evaluation. With advances in cancer treatment and tumor imaging, a simpler criterion based on one-dimensional rather than bi-dimensional (WHO) tumor measurement, named Response Evaluation Criteria in Solid Tumors (RECIST) was introduced in 2000. Both approaches have four response categories: complete response, partial response, stable disease and progressive disease (PD). Bi-dimensional measurement data of 151 patients with ABC were analysed with WHO and RECIST criteria to compare their response categories and inter criteria reproducibility by Kappa statistics. There was 94% concordance and 9/151 patients were recategorized with RECIST including 6/12 PD cases. RECIST therefore under-estimates and delays diagnosis of PD. This is undesirable because it may delay or negate switch over to alternate therapy. Analysis was repeated with a new criteria named RECIST-Breast (RECIST-B), with a lower threshold for PD (${\geq}10%$ rather than ${\geq}20%$ increase of RECIST). This showed higher concordance of 97% with WHO criteria and re-categorization of only 4/151 patients (1/12 PD cases). RECIST-B criteria therefore have advantages of both ease of measurement and calculations combined with excellent concordance with WHO criteria, providing a practical clinical tool for response evaluation and offering good comparison with past and current clinical trials of NACT using WHO guidelines.

Evaluation of Clinical Alarms and Alarm Management in Intensive Care Units (중환자실에서 사용되는 의료장비의 경보음 발생과 관리 현황)

  • Jeong, Yu Jin;Kim, Hyunjung
    • Journal of Korean Biological Nursing Science
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    • v.20 no.4
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    • pp.228-235
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    • 2018
  • Purpose: This study aimed to investigate the clinical alarm occurrence and management of nurses toward clinical alarms in the intensive care unit (ICU). Methods: This observational study was conducted with 40 patients and nurses cases in two ICUs of a university hospital. This study divided 24 hours into the unit of an hour and conducted two times of direct observation per unit hour for 48 hours targeting the medical devices applied to 40 patients. Data were analyzed using IBM SPSS Statistics 23. Results: On average, 3.8 units of medical devices were applied for each patient and the ranges of alarm settings were wide. During 48 hours, 184 cases of clinical alarm were occurred by four types of medical devices including physiological monitors, mechanical ventilators, infusion pumps, and continuous renal replacement therapy. Among them, false alarm was 110 cases (59.8%). As for the alarm management by ICU nurses, two-minute alarm mute took up most at 38.0% (70 cases), and no response was second most at 32.6% (60 cases). When valid alarm sounded, nurses showed no response at 43.2%. Conclusion: The findings suggest that a standard protocol for alarm management should be developed for Korean ICU settings. Based on the protocol, continuous training and education should be provided to nurses for appropriate alarm management.

A Study on the Early Response System Subway Cabin Arson Fire (지하철 차량 방화사고 초기대응에 관한 연구)

  • Roh, Sam-Kew;Ham, Eun-Gu;Kim, Si-Gon
    • Fire Science and Engineering
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    • v.20 no.2 s.62
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    • pp.21-30
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    • 2006
  • Since Daegu subway arson fire disaster in 2003, there have been several copycat crimes such as at Seoul Metro line number seven and Hongkong Chuiwan line cases. Oil and gas were used for fire propagation in most cases as in Daegu case and such fire could be expanded to a whole subway cabin within several minutes. The fire may eventually cause the whole subway system stop. Fire damage can be minimized when fire occurrence and diffusion are blocked by stages or isolated rapidly. This study suggests an effective early response system that separates passengers from fire and a real-time fire extinguishment program by stages. Based on the subway arson case studies, the early response scenario has been structured by three stages, i.e., confirmation of fire and damage, early fire extinguishment, and information dissemination and passengers evacuation.

Optimization of Angled Ribs for Heat Transfer Enhancement in a Square Channel with Bleed Flow (유출유동을 가진 정사각유로 내 열전달 향상을 위한 경사진 요철 최적설계)

  • Lee, Hyun;Kim, Kyung-Min;Lee, Dong-Hyun;Cho, Hyung-Hee
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.4
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    • pp.300-306
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    • 2008
  • In the present study, the second order response surface method (RSM) is carried out to get optimum thermal design for enhancing heat transfer in a square channel with bleed flow. The RSM is used as an optimization technique. To calculate the heat transfer, RNG k-epsilon model and enhanced wall function are used. To design optimum rib turbulators, two design variables such as attack angle of rib $({\alpha})$ and rib pitch-to-rib height ratio (p/e) are optimized. In these analyses, the channel inlet Reynolds number was fixed at 10,000 in both non-bleeding and bleeding cases. The response surfaces of two design variables are constructed in cases with and without bleed flow. As a result, the optimum (or highest) heat transfer values are almost the same in ranges of two cases with and without bleed flow. However, the friction losses in the case with bleed flow are lower than those without bleed flow.

Third-line Hormonal Therapy to Treat Prostate Cancer Relapse after Initial and Second-line Hormonal Therapy: Report of 52 Cases and Literature Review

  • Matsumoto, Kazuhiro;Hagiwara, Masayuki;Hayakawa, Nozomi;Tanaka, Nobuyuki;Ito, Yujiro;Maeda, Takahiro;Ninomiya, Akiharu;Nagata, Hirohiko;Nakamura, So
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3645-3649
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    • 2014
  • The aim of this study was to evaluate the efficacy of third-line combined androgen blockade (CAB) therapy for castration-resistant prostate cancer that relapsed after primary and second-line CAB. We retrospectively reviewed the medical records of 52 patients who received first-, second-, and third-line CAB therapy (medical or surgical castration, plus steroidal antiandrogen of chlormadinone acetate, or nonsteroidal antiandrogen of flutamide or bicalutamide). For cumulative analysis, we searched the PubMed database and identified a total of 50 cases published in English. Including our cases, this provided a total of 102 cases for analysis. In our study cohort, 11 cases (21.2%) achieved more than 50% reduction of serum prostate-specific antigen (PSA) on initiation of third-line CAB. We found that third-line CAB with nonsteroidal antiandrogen after second-line CAB with steroidal antiandrogen exhibited favorable results, with a positive response in six of 13 patients (46.2%). Cumulative analysis findings were comparable. Regarding the timing of third-line CAB administration, 15 patients had started at a PSA equal to or less than 4.0 ng/ml, and eight of them (53.3%) showed a positive response to treatment, compared to only three of 37 patients (8.1%) whose PSA at the initiation of third-line therapy was higher than 4.0 ng/ml (p<0.001). We conclude that third-line CAB with nonsteroidal antiandrogen would be particularly useful for patients whose cancer progressed after second-line CAB with steroidal antiandrogen. The timing of treatment seems to be important because the higher the PSA at the start of third-line therapy, the lower the PSA response rate.

Clinical Observation of Thymoma (종격동 흉선종양의 임상적 고찰)

  • Jang, Un-Ha;Lee, Jeong-Ho;Ryu, Hoe-Seong
    • Journal of Chest Surgery
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    • v.10 no.2
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    • pp.355-358
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    • 1977
  • The period from .1959 to 1976, authors experienced 13 cases of thymoma at the Department of Thoracic and Cardiovascular Surgery in National Medical Center. Ten patients were male, and 3 patients were female.Main complaints were cough 76.9%, dyspnea, 69.2%, chest pain 61.6%, myasthenia gravis 23.1 % and S.V.S 23.1%. All of them located anterior mediastinum. 7 cases were benign and 6 cases were malignant. Lymphocytic type was 5 cases, epithelial type 3 case,spindle cell type 1 case, mixed type 2 cases, cystic type 1 case and seminomatous type 1 case. All cases were surgically approached but in malignant cases, only 1 case was palliatively removed and followed radiation therapy. 4 cases were made only biopsy, among them, obstained good response with radiation therapy in seminomatous type case. In benign cases, excellent result was obtained but 2 cases which were combined myasthenia gravis were relapsed the symptoms.

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