• 제목/요약/키워드: current division technique

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Surgical prevention of terminal neuroma and phantom limb pain: a literature review

  • Bogdasarian, Ronald N.;Cai, Steven B.;Tran, Bao Ngoc N.;Ignatiuk, Ashley;Lee, Edward S.
    • Archives of Plastic Surgery
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    • 제48권3호
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    • pp.310-322
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    • 2021
  • The incidence of extremity amputation is estimated at about 200,000 cases annually. Over 25% of patients suffer from terminal neuroma or phantom limb pain (TNPLP), resulting in pain, inability to wear a prosthetic device, and lost work. Once TNPLP develops, there is no definitive cure. Therefore, there has been an emerging focus on TNPLP prevention. We examined the current literature on TNPLP prevention in patients undergoing extremity amputation. A literature review was performed using Ovid Medline, Cochrane Collaboration Library, and Google Scholar to identify all original studies that addressed surgical prophylaxis against TNPLP. The search was conducted using both Medical Subject Headings and free-text using the terms "phantom limb pain," "amputation neuroma," and "surgical prevention of amputation neuroma." Fifteen studies met the inclusion criteria, including six prospective trials, two comprehensive literature reviews, four retrospective chart reviews, and three case series/technique reviews. Five techniques were identified, and each was incorporated into a targetbased classification system. A small but growing body of literature exists regarding the surgical prevention of TNPLP. Targeted muscle reinnervation (TMR), a form of physiologic target reassignment, has the greatest momentum in the academic surgical community, with multiple recent prospective studies demonstrating superior prevention of TNPLP. Neurorrhaphy and transposition with implantation are supported by less robust evidence, but merit future study as alternatives to TMR.

직류모터의 속도 제어를 위한 PID 제어기 동조 (PID controller tuning of DC motor for speed control)

  • 소명옥;이윤형;안종갑;최우철
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 추계학술대회
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    • pp.111-116
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    • 2004
  • 이 논문에서는 모델조정기법과 실수코딩 유전알고리즘을 이용하여 주어진 직류모터 시스템의 파라미터를 추정하였다. 종래에 논 Ziegler- Nichols(Z-N)동조법, Cohen-Coon(C-C)동조법, IMC(Internal model control)동조법, Lopez ITAE(L-ITAE)동조법과 같이 경험적이고 실험적인 많은 방법들이 제안되었다. 본 논문에서는 실수코딩 유전알고리즘을 이용하여 PID 제어기의 파라미터들을 동조하는 방법을 제안하고 시뮬레이션과 실험을 통해 제안한 제어기의 성능을 증명하였다.

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크롬환원제와 인산염으로 처리된 6가 크롬 오염토양의 고정화 (Immobilization Characteristics of Hexavalent Chromium Contaminated Soils Treated with Phosphate and Chromium Reducing Agent)

  • 이의상
    • 환경영향평가
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    • 제16권1호
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    • pp.27-33
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    • 2007
  • Hexavalent chromium-contaminated soils are encounted at many unregulated discharge and improper handling of wastes from electroplating, leather tanning, steelmaking, corrosion control, and wood preservation industries. Contamination of hexavalent chromium in the soil is a major concern because of its toxicity and threat to human life and environment. Current technologies for hexavalent chromium-contaminated soil remediation are usually costly and/or cannot permanently prohibit the toxic element from entering into the biosphere. Thus, as an alternative technique, immobilization is seen as a cost-effective and promising remediation technology that may reduce the leachable potential of hexavalent chromium. The purpose of this paper is to develope an immobilization technique for the formation of the geochemically stabilized hexavalent chromium-contaminated soil from the reactions of labile soil hexavalent chromium forms with the added soluble phosphate and chromium reducing agent. From the liquid phase experiment, reaction order of chromium reducing agent, soluble phosphate, alkali solution shows the best removal efficiency of 95%. In addition, actual soil phase experiment demonstrates up to 97.9% removal efficiency with 1:1 molar ratio of chromium reducing agent and soluble phosphate. These results provide evidence for the potential use of soluble phosphate and chromium reducing agent for the hexavalent chromium-contaminated soil remediation.

인공지능을 이용한 3차원 구조물의 최적화 설계 : 마이크로 가속도계에 적용 (Optimal Design for 3D Structures Using Artificial Intelligence : Its Application to Micro Accelerometer)

  • Lee, Joon-Seong
    • 한국지능시스템학회논문지
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    • 제14권4호
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    • pp.445-450
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    • 2004
  • 본 논문은 실질적인 최적화 구조물의 설계를 위한 시스템에 대한 것으로 퍼지이론에 바탕을 둔 자동 유한요소 생성 망 기술과 계산 기하학적 기술, 해석코드 및 솔리드모델러를 시스템에 통합시켰다. 최적해 또는 만족해는 자동해석 시스템과 함께 탐색공간을 위한 유전자 알고리즘을 이용하여 자동적으로 탐색되어 진다. 또한, 유전자 알고리즘을 이용함으로써 본 설계 시스템은 다차원 해를 얻을 수 있다. 개발된 시스템은 터널전류에 바탕을 둔 마이크로 가속도계의 형상설계에 적용하였다.

소프트 스위칭 기법을 이용한 ZVS-HB형 고주파 공진 DC-DC 컨버터의 설계 및 특성해석 (A Design and Characteristic Analysis of ZVS-Half Bridge type High-Frequency Resonant DC-DC Converter Using Soft-Switching Technique)

  • 오경섭;남승식;김경식;김동희;노채균
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제50권4호
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    • pp.179-187
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    • 2001
  • In recent years, the switching source devices have the advantage of small, light and high reliability with the high-frequency. But, high-frequency switching has disclosed disadvantage of result from stress and turn-on and turn-off peak losses at the switching instant. Accordingly, in this paper propose ZVS-HB type high-frequency resonant DC/DC converter using soft switching technique (Zero-Voltage-Switching, Zero-Current-Switching) with safety operating of circuit at diving on inductive zone, through the circuit design example using the capacitor $C_3,\;C_4$ with soft switching function and division characteristic of resonant Capacitor C, $C_1,\;C_2$, and, the characteristic analysis of circuit is generally described using normalized parameters. Also, this paper certified a rightfulness of characteristic analysis in comparison with a theoretical values and a experimental values obtain from experiment using MOSFET.

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Simulative Investigation of Spectral Amplitude Coding Based OCDMA System Using Quantum Logic Gate Code with NAND and Direct Detection Techniques

  • Sharma, Teena;Maddila, Ravi Kumar;Aljunid, Syed Alwee
    • Current Optics and Photonics
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    • 제3권6호
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    • pp.531-540
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    • 2019
  • Spectral Amplitude Coding Optical Code Division Multiple Access (SAC OCDMA) is an advanced technique in asynchronous environments. This paper proposes design and implementation of a novel quantum logic gate (QLG) code, with code construction algorithm generated without following any code mapping procedures for SAC system. The proposed code has a unitary matrices property with maximum overlap of one chip for various clients and no overlaps in spectra for the rest of the subscribers. Results indicate that a single algorithm produces the same length increment for codes with weight greater than two and follows the same signal to noise ratio (SNR) and bit error rate (BER) calculations for a higher number of users. This paper further examines the performance of a QLG code based SAC-OCDMA system with NAND and direct detection techniques. BER analysis was carried out for the proposed code and results were compared with existing MDW, RD and GMP codes. We demonstrate that the QLG code based system performs better in terms of cardinality, which is followed by improved BER. Numerical analysis reveals that for error free transmission (10-9), the suggested code supports approximately 170 users with code weight 4. Our results also conclude that the proposed code provides improvement in the code construction, cross-correlation and minimization of noises.

Polarity Index Dependence of M13 Bacteriophage-based Nanostructure for Structural Color-based Sensing

  • Lee, Yujin;Moon, Jong-Sik;Kim, Kyujung;Oh, Jin-Woo
    • Current Optics and Photonics
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    • 제1권1호
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    • pp.12-16
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    • 2017
  • Color sensor systems based on M13 bacteriophage are being considerably researched. Although many studies on M13 bacteriophage-based chemical sensing of TNT, endocrine disrupting chemicals, and antibiotics have been undertaken, the fundamental physical and chemical properties of M13 bacteriophage-based nanostructures require further research. A simple M13 bacteriophage-based colorimetric sensor was fabricated by a simple pulling technique, and M13 bacteriophage was genetically engineered using a phage display technique to exhibit a negatively charged surface. Arrays of structurally and genetically modified M13 bacteriophage that can determine the polarity indexes of various alcohols were found. In this research, an M13 bacteriophage-based color sensor was used to detect various types of alcohols, including methanol, ethanol, and methanol/butanol mixtures, in order to investigate the polarity-related property of the sensor. Studies of the fundamental chemical sensing properties of M13 bacteriophage-based nanostructures should result in wider applications of M13 bacteriophage-based colorimetric sensors.

Spectrally encapsulated OFDM: Vectorized structure with minimal complexity

  • Kim, Myungsup;Kwak, Do Young;Jung, Jiwon;Kim, Ki-Man
    • ETRI Journal
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    • 제43권4호
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    • pp.660-673
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    • 2021
  • To efficiently use frequency resources, the next 6th generation mobile communication technology must solve the problem of out-of-band emission (OoBE) of cyclic prefix (CP) orthogonal frequency division multiplexing (OFDM), which is not solved in 5th generation technology. This study describes a new zero insertion technique to replace an existing filtering scheme to solve this internal problem in OFDM signals. In the development of the proposed scheme, a precoder with a two-dimensional structure is first designed by generating a two-dimensional mapper and using the specialty of each matrix. A spectral shaping technique based on zero insertion instead of a long filter is proposed, so it can be applied not only to long OFDM symbols, but also very short ones. The proposed method shows that the transmitted signal is completely blocked at the bandwidth boundaries of signals according to the current standards, and it is confirmed that the proposed scheme is ideal with respect to bit error rate (BER) performance because its BER is the same as that of CP-OFDM. In addition, the proposed scheme can transformed into a real time structure through vectorizing process with minimal complexity.

건설사업관리자(CMr) 측면에서 건설기술용역 평가의 CSFs 추출 및 AHP 중요도 분석 (CSFs Extraction and AHP Importance Analysis for Construction Technology Services Evaluation in terms of Construction Manager)

  • 양진국;홍성욱
    • 대한건축학회논문집:구조계
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    • 제36권3호
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    • pp.129-134
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    • 2020
  • The current evaluation time period for the construction management service is the project completion or after project completion. Therefore, the construction manager has the following problems. First, it is difficult to prepare the evaluation due to the new field movement of the existing participating engineer. Next, the CM work is complex as well as extensive. Therefore, the critical success factors of the construction technology services evaluation are required as a systematic performance standard of CM work. In this study, we extracted the critical success factors that can systematically prepare the evaluation from the early stage of the project through in - depth interviews with experts. And, this study was analyze the priority of each factor by using AHP technique. As a result, the most important factors were related to the systemization of the preparation process, the construction manager work capabilities and practical construction management. And the priorities of all factors were analyzed high in the factors suggested by the owner groups. The results of this analysis are expected to provide the standards that construction management service performer carry out structured management of construction management throughout the project.

A study on Countermeasures by Detecting Trojan-type Downloader/Dropper Malicious Code

  • Kim, Hee Wan
    • International Journal of Advanced Culture Technology
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    • 제9권4호
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    • pp.288-294
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    • 2021
  • There are various ways to be infected with malicious code due to the increase in Internet use, such as the web, affiliate programs, P2P, illegal software, DNS alteration of routers, word processor vulnerabilities, spam mail, and storage media. In addition, malicious codes are produced more easily than before through automatic generation programs due to evasion technology according to the advancement of production technology. In the past, the propagation speed of malicious code was slow, the infection route was limited, and the propagation technology had a simple structure, so there was enough time to study countermeasures. However, current malicious codes have become very intelligent by absorbing technologies such as concealment technology and self-transformation, causing problems such as distributed denial of service attacks (DDoS), spam sending and personal information theft. The existing malware detection technique, which is a signature detection technique, cannot respond when it encounters a malicious code whose attack pattern has been changed or a new type of malicious code. In addition, it is difficult to perform static analysis on malicious code to which code obfuscation, encryption, and packing techniques are applied to make malicious code analysis difficult. Therefore, in this paper, a method to detect malicious code through dynamic analysis and static analysis using Trojan-type Downloader/Dropper malicious code was showed, and suggested to malicious code detection and countermeasures.