• Title/Summary/Keyword: Stable Response

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Rotordynamic Analysis and Experiment of Superconducting Magnetic Bearings-Flywheel System (초전도 자기베어링-플리이휠 시스템의 회전체 해서 및 실험)

  • Kim, Jong-Soo;Lee, Soo-Hun
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.9
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    • pp.104-109
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    • 1999
  • The flywheel energy storage system using superconducting magnetic bearings is a device to store electrical energy as rotatioal kinetic energy by motor and to convert it to electrical energy by generator when it is necessary. The rotordynamic analysis should be performed with an adequate analytical model and equations of motion to identify the stable driving condition and the dynamic behavior. The critical speed and the unbalance response of superconducting magnetic bearings-flywheel system are studied in this paper. The analytical results show that the system has one forward whirling mode and two backward whirling models below 500rpm. The maximum displacement 0.75mm is detected at the first forward mode (385rpm)through unbalance response analysis. The analytical results are compared with the experimental result by the spin-down test. The experimental result shows that the maximum displacement is 0.7mm at 370rpm.

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Seismic Response of Exterior Beam-Column-Slab connection using High-Strength Materials (고강도 재료를 사용한 외부 보-기둥-슬래브 접합부의 지진응답)

  • 장극관
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.343-350
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    • 1999
  • The purpose of this study is to compare the response of the high-strength concrete beam-column-slab subassembly with the response of a normal-strength concrete specimens. Four assemblies were designed 2/3 scale beam-column-slab joint(fc'=240kg/cm2 fc'=700kg/cm2) and tested to investigate seismic behaviour. From the test results 1) flexral cracks emerge to inside of bean deeply for high strength concrete member 2) the high-strength specimens represented stable hysteretic behaviour for the displacement ductility 5.5 but degradation in stiffness and strength and unstable hysteretic behaviors were observed owing to the brittleness of high-strength concrete beyond its range.

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Computational simulation of intelligent big data analysis under nanotube rotation

  • Lunan Li;Allam Maalla
    • Advances in nano research
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    • v.14 no.1
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    • pp.67-80
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    • 2023
  • Economic investigation is one of the main issues regarding the design and production of small-scale structures. This paper concerns the creation, implementation, and economic aspects of the cross-section profile of small-scale structures regarding the dynamic response of the free and forced vibration behavior of spinning nanoscale beams based on big data analysis. According to the financial analysis, the three practical non-uniform functions of cross-sections are compared to the uniform beam in the same weight and the equal material used. The previous studies reported that the uniform beams are more stable and contain a better frequency response based on the mechanical analysis. Still, concerning the economic investigation, which means the considered structures should have equal length and have the same weight in the aspect of material used, the conclusion can be different from the mechanical aspect. Consequently, in the current paper, the dynamic response along with computer technology as well as the big data analysis of the free and forced vibration of the nanobeam regarding the economic shape of the cross-section is scrutinized.

Clinical Application of the Adenosine Triphosphate-based Response Assay in Intravesical Chemotherapy for Superficial Bladder Cancer

  • Ge, Wen-Qing;Pu, Jin-Xian;Zheng, Shi-Ying
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.2
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    • pp.689-692
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    • 2012
  • Objective: To investigate correlations between adenosine triphosphate chemotherapy response assay (ATP-CRA) and clinical outcomes after ATP-CRA-based chemotherapy for drug selection in patients receiving intravesical chemotherapy to prevent recurrence of superficial bladder cancer after surgery. Methods: The chemosensitivities of 12 anticancer drugs were evaluated, including 5-Fu ADM, and EPI, using ATP-CRA and primary tumor cell culture in 54 patients. In addition, a further 58 patients were treated according to clinical experience. Differences in post-chemotherapeutical effects between drug sensitivity assay and experience groups were compared. Results: The evaluable rate of the test was 96.3%, the clinical effective rate was 80.8%, the sensitivity rate was 97.6% (41/42), the specificity was 20%, the total predicting accuracy was 74.3%, the positive predictive value was 83.7% (41/49), the negative predictive value was 66.7% (2/3); in the drug sensitivity test group, the clinical effective rate was 80.8%, the experience group response rate was 63.8%, with a significant difference in clinical effects between the ATP-based sensitivity and experience groups (${\chi}^2$=7.0153, P<0.01). Conclusion: ATP-CRA is a stable, accurate and potentially practical chemosensitivity test providing a predictor of chemotherapeutic response in patients with superficial bladder cancer.

Modeling of Hanlim's gas turbine generator & qualitative analysis of PSS operation (한림가스터빈 발전기/제어계의 모델링 및 PSS 동작의 정성적 분석)

  • Choi, K.S.;Moon, Y.H.;Kim, D.J.;Choo, J.B.;Lyu, S.H.
    • Proceedings of the KIEE Conference
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    • 1996.11a
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    • pp.95-98
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    • 1996
  • Response speed of generator/control system kas increased with the aid of the development of power electronics. Even though it is desirable to enhance response speed for the control system(AVR/Gov) of generator itself, in case a certain generator/control system with high response excitation system is connected with bulk power system, terminal voltage and active power of some generators can oscillate with adjoining generators or near area when even a little of disturbance take place. PSS(Power System Stabilizer) is used to damp rotor swing by adding the supplementary signal in phase with speed. As the stable AVR response is very important before PSS is installed, modeling and analysis of generator/control system was performed. Next we have analysed PSS response of Hanlim's gas turbine by transmission line open/close test.

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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.

Modeling of Near Fault Ground Motion due to Moderate Magnitude Earthquakes in Stable Continental Regions (안정대륙권역의 중규모지진에 의한 근단층지반운동의 모델링)

  • Kim, Jung-Han;Kim, Jae-Kwan
    • Journal of the Earthquake Engineering Society of Korea
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    • v.10 no.3 s.49
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    • pp.101-111
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    • 2006
  • This paper proposes a method for modeling new fault ground motion due to moderate size earthquakes in Stable Continental Regions (SCRs) for the first time. The near fault ground motion is characterized by a single long period velocity pulse of large amplitude. In order to model the velocity pulse, its period and peak amplitude need be determined in terms of earthquake magnitude and distance from the causative fault. Because there have been observed very few new fault ground motions, it is difficult to derive the model directly from the recorded data in SCRs. Instead an indirect approach is adopted in this work. The two parameters, the period and peak amplitude of the velocity pulse, are known to be functions of the rise time and the slip velocity. For Western United States (WUS) that belongs active tectonic regions, there art empirical formulas for these functions. The relations of rise time and slip velocity on the magnitude in SCRs are derived by comparing related data between Western United States and Central-Eastern United States that belongs to SCRs. From these relations, the functions of these pulse parameters for NFGM in SCRs can be expressed in terms of earthquake magnitude and distance. A time history of near fault ground motion of moderate magnitude earthquake in stable continental regions is synthesized by superposing the velocity pulse on the for field ground motion that is generated by stochastic method. As an demonstrative application, the response of a single degree of freedom elasto-plastic system is studied.

Fabrication of $In_2O_3$-based oxide semiconductor thick film ozene gas sensor ($In_2O_3$ 계 산화물 반도체형 후막 오존 가스센서의 제조)

  • 이규정
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.1
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    • pp.19-24
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    • 1999
  • $In_2O_3$-based thick films for the ozone detection of ppb range have been investigated. The $In_2O_3$ sensing layer is quite sensitive to ozone, but the saturated stable sensitivity cannot be obtained at the ozone exposure of 100 ppb for 5 min. The addition of $Fe_2O_3$ into $In_2O_3$ indicates some improvement in response time and sensitivity, but it seems the improvement is not good enough for real applications. Firing of $In_2O_3$:$Fe_2O_3$ powder induces remarkable improvement in response and recovery, although the sensitivity decrease. The sensing layer fired at $1300^{\circ}C$ and operated $550^{\circ}C$ shows excellent properties of fast response time, saturated stable sensitivity and rapid recovery characteristics to 100 ppb ozone exposure for 5 min. Especially, it shows the reproducibility of the sensor signal for repeated measurements and the linearity between the ozone concentration and the sensor resistance. The preliminary results clearly demonstrated that the sensor can be successfully applied for the ozone detection of ppb range.

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Seismic response analysis of virtual honam-jeju subsea tunnel (지진시 가상 호남-제주 해저터널의 지반응답 특성)

  • Kwak, Chang-Won;Jang, Dong-In;Park, Inn-Joon;Park, Seong-Yong
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.18 no.3
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    • pp.319-329
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    • 2016
  • Underground structures such as subsea tunnel having large section should be stable against seismic loads. In general, underground structures show more stable behavior due to the limited dynamic motion and force, and considerable energy dissipation; however, severe damage was reported from recent earthquakes. Therefore, more sophisticated and analytic approach is required to investigate the seismic response of underground structure like subsea tunnel. In this study, seismic analysis of virtual Honam-Jeju subsea tunnel are performed. Consequently, stresses and forces of tunnel lining increased at fractured and/or weak rock zones. Stresses and forces of tunnel lining also increased at large section under axially deformed condition; however, decrease under transversely deformed condition.

Postoperative Cure for Metastatic Gastrointestinal Stromal Tumor (전이성 위장관 기질종양의 수술 후 완치)

  • Park, Eun Hyea;Kim, Jin Il;Cheung, Dae Yong;Park, Soo-Heon
    • The Korean journal of helicobacter and upper gastrointestinal research
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    • v.18 no.4
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    • pp.264-270
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    • 2018
  • Gastrointestinal stromal tumor (GIST) is a mesenchymal tumor derived from Cajal cells originating from the myotonic plexus. The expression of tyrosine kinase (KIT) membrane receptors that are active on KIT is inhibited by the KIT inhibitor imatinib mesylate. GISTs are resistant to conventional chemotherapy, and radiation therapy is not significantly beneficial for GISTs. With the development of imatinib mesylate, approximately 81.6% of patients with advanced and metastatic GIST exhibit an effect above the stabilization response, thereby increasing the survival time. However, imatinib mesylate alone is unlikely to cure metastatic GISTs. Even with a partial or stable response, imatinib mesylate may be used for a longer time period. However, resection of grossly visible lesions should be considered for patients with a stable response during surgical treatment. In this study, we present a case of GIST with liver metastasis after imatinib mesylate treatment, which was followed up without recurrence after partial resection.