• 제목/요약/키워드: Combined procedures

검색결과 426건 처리시간 0.032초

패턴 인식에 의한 새로운 자동조정 PI제어기 (A New Auto-Tuning PI Controller by Pattern Recognition)

  • Park, Gwi-Tae;Lee, Kee-Sang;Park, Tae-Hong
    • 대한전기학회논문지
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    • 제40권7호
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    • pp.696-705
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    • 1991
  • This paper describes the procedures for pre-tuning and re-tuning the gains of PI controller based on output patterns -output error integral- of the unknown process which may not have any information, for example, system order, deadtime, time constant, etc. The key ideas of the proposed adaptive scheme are as follows. The scheme determines the initial gains by using ZNM (Ziegler-Nichols Method) with relay feedback, and then the adaptive algorithms by pattern recognition are introduced for re-runing the PI gains with on-line scheme whenever control conditions are changed. Because, among the various auto-tuning procedures, ANM with relay feedback has the difficulty in re-tuning with on-line and Bristol method has no comment on initial settings and has variables to pre-determine, which makes the algorithm comples, the proposed methods have the combined scheme with above two procedures to recover those problems. And this paper proposes a simple way to determine adaptive constant in Bristol method. To show the validity of the proposed method, an example is illustrated by computer simulation and a laboratory process, heat exchanger, is experimented.

Surgical management of hilar cholangiocarcinoma: Controversies and recommendations

  • Suvendu Sekhar Jena;Naimish N Mehta;Samiran Nundy
    • 한국간담췌외과학회지
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    • 제27권3호
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    • pp.227-240
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    • 2023
  • Hilar cholangiocarcinomas are highly aggressive malignancies. They are usually at an advanced stage at initial presentation. Surgical resection with negative margins is the standard of management. It provides the only chance of cure. Liver transplantation has increased the number of 'curative' procedures for cases previously considered to be unresectable. Meticulous and thorough preoperative planning is required to prevent fatal post-operative complications. Extended resection procedures, including hepatic trisectionectomy for Bismuth type IV tumors, hepatopancreaticoduodenectomy for tumors with extensive longitudinal spread, and combined vascular resection with reconstruction for tumors involving hepatic vascular structures, are challenging procedures with surgical indications expanded. Liver transplantation after the standardization of a neoadjuvant protocol described by the Mayo Clinic has increased the number of patients who can undergo operation.

저지대역 특성이 개선된 이중 E-평면 대역통과 여파기의 설계 (Design of Double E-Plane Bandpass Filters with Improved Stopband Characteristics)

  • 임재봉
    • 한국광학회:학술대회논문집
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    • 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.248-251
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    • 1990
  • A new CAD program for double E-plane bandpass filters is developed based on the variational analysis method and the passband correction method combined with the synthesis procedures. By taking the widths of three narrow waveguide equally, we can design bandpass filters with best stopband characteristics.

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비파괴시험 자료를 적용한 콘크리트 기준강도의 통계적 추정 (Statistical Estimation of Specified Concrete Strength by Applying Non-Destructive Test Data)

  • 백인열
    • 한국안전학회지
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    • 제30권1호
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    • pp.52-59
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    • 2015
  • The aim of the paper is to introduce the statistical definition of the specified compressive strength of the concrete to be used for safety evaluation of the existing structure in domestic practice and to present the practical method to obtain the specified strength by utilizing the non-destructive test data as well as the limited number of core test data. The statistical definition of the specified compressive strength of concrete in the design codes is reviewed and the consistent formulations to statistically estimate the specified strength for assessment are described. In order to prevent estimating an unrealistically small value of the specified strength due to limited number of data, it is proposed that the information from the non-destructive test data is combined to that of the minimum core test data. The the sample mean, standard deviation and total number of concrete test are obtained from combined test data. The proposed procedures are applied to an example test data composed of the artificial numerical values and the actual evaluation data collected from the bridge assessment reports. The calculation results show that the proposed statistical estimation procedures yield reasonable values of the specified strength for assessment by applying the non-destructive test data in addition to the limited number of core test data.

Combined Endovascular and Microsurgical Procedures as Complementary Approaches in the Treatment of a Single Intracranial Aneurysm

  • Lim, Yong-Cheol;Shin, Yong-Sam;Chung, Joon-Ho
    • Journal of Korean Neurosurgical Society
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    • 제43권1호
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    • pp.21-25
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    • 2008
  • Objective : Both endovascular coil embolization and microsurgical clipping are now firmly established as treatment options for the management of cerebral aneurysms. Moreover, they are sometimes used as complementary approaches each other. This study retrospectively analyzed our experience with endovascular and microsurgical procedures as complementary approaches in treating a single aneurysm. Methods : Nineteen patients with intracranial aneurysm were managed with both endovascular and microsurgical treatments. All of the aneurysms were located in the anterior circulation. Eighteen patients presented with SAH, and 14 aneurysms had diameters of less than 10 mm, and five had diameters of 10-25 mm. Results : Thirteen of the 19 patients were initially treated with endovascular coil embolization, followed by microsurgical management. Of the 13 patients, 9 patients had intraprocedural complications during coil embolization (intraprocedural rupture, coil protrusion, coil migration), rebleeding with regrowth of aneurysm in two patients, residual sac in one patient, and coil compaction in one patient. Six patients who had undergone microsurgical clipping were followed by coil embolization because of a residual aneurysm sac in four patients, and regrowth in two patients. Conclusion : In intracranial aneurysms involving procedural endovascular complications or incomplete coil embolization and failed microsurgical clipping, because of anatomical and/or technical difficulties, the combined and complementary therapy with endovascular coiling and microsurgical clipping are valuable in providing the best outcome.

눈에 띄는 흉의 생성 없는 내안각췌피 교정술 (Correction of the Epicanthal Fold with Invisible Scar)

  • 이윤호;이시우;백롱민
    • Archives of Plastic Surgery
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    • 제32권3호
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    • pp.299-303
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    • 2005
  • The epicanthal fold is common natural finding in Asian eyes. It is very common that patients, who look for oriental blephaloplasty for double eye lid, request correction epicanthal fold. It is very often difficult to achieve satisfactory results if the correction of the epicanthal fold is not corrected concomitantly. Many authors described surgical procedures for correction of epicanthal folds. But most of them leave additional scars which tend to be hypertrophic and noriceable. We achieved satisfactory result in epicanthoplasty with invisible scar, using combination of procedures, such as upward incision, double eyelid operation, anchoring suture of the medial upper lid skin to the medial canthal tendon, trans-nasal root subcutaneous mattress suture of the epicanthal fold itself and combined rhinoplasty. For past six years (1998 to 2003) 17 patients have been operated with one of these mentioned procedures. The mean follow up was 4months (2weeks to 6months). All patients were satisfied and no major complication was noted. This method can be one of the effective procedures for correcting the Asian epicanthal fold for avoiding potential visible scar and ancillary procedure in double eye lid blephaloplasty.

Small scale experimental testing to verify the effectiveness of the base isolation and tuned mass dampers combined control strategy

  • Petti, Luigi;Giannattasio, Giovanni;De Iuliis, Massimiliano;Palazzo, Bruno
    • Smart Structures and Systems
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    • 제6권1호
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    • pp.57-72
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    • 2010
  • This paper presents the most significant results obtained within a broad-ranging experimental program aiming to evaluate both the effectiveness and the robustness of a Base Isolation (BIS) and a Tuned Mass Damper (TMD) combined control strategy (BI & TMD). Following a brief description of the experimental model set-up and the adopted kinematic scaling technique, this paper describes the identification procedures carried out to characterize the system''s model. The dynamic response of a small-scale model to recorded earthquake excitations, which has been scaled by using the Buckingham pi-theorem, are later presented and discussed. Finally, the effectiveness and robustness of the combined control strategy is evaluated by comparing the model's dynamic response. In particular, reduction in relative displacements and absolute accelerations due to the application of different mass damping systems is investigated.

쉘 구조물의 비선형 동적응답 해석을 위한 Algorithm에 관한 연구 (A Study on the Algorithm for Nonlinear Dynamic Response Analysis of Shell Structure)

  • 최찬문
    • 수산해양기술연구
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    • 제32권2호
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    • pp.164-176
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    • 1996
  • The main intention of this paper is to develop and compare the algorithm based on finite element procedures for nonlinear transient dynamic analysis which has combined effects of material and geometric nonlinearities. Incremental equilibrium equations based on the principle of virtual work are derived by the finite element approach. For the elasto - plastic large deformation analysis of shells and the determination of the displacement-time configuration under time-varying loads, the explicit, implicit and combined explicit-implicit time integration algorithm is adopted. In the time structure is selected and the results are compared with each others. Isoparametric 8-noded quadrilateral curved elements are used for shell structure in the analysis and for geometrically nonlinear elastic behaviour, a total Lagrangian coordinate system was adopted. On the other hands, material nonlinearity is based on elasto-plastic models with Von-Mises yield criteria. Thus, the combined explicit-implicit time integration algorithm is benefit in general case of shell structure, which is the result of this paper.

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