• Title/Summary/Keyword: DI model

Search Result 402, Processing Time 0.023 seconds

Removal of Cu(II) and Pb(II) by Solid-Phase Extractant Prepared by Immobilizing D2EHPA with Polysulfone (D2EHPA를 Polysulfone으로 고정화하여 제조한 고체상 추출제에 의한 Cu(II)와 Pb(II)의 제거)

  • Kam, Sang-Kyu;Jeon, Jin-Woo;Lee, Min-Gyu
    • Journal of Environmental Science International
    • /
    • v.23 no.11
    • /
    • pp.1843-1850
    • /
    • 2014
  • PS-D2EHPA beads were prepared by immobilizing di-2-ethylhexyl-phosphoric acid (D2EHPA) with polysulfone (PSf). The removal experiments of Cu(II) and Pb(II) by the prepared PS-D2EHPA beads were conducted batchwise. The removal efficiency of Cu(II) and Pb(II) by PS-D2EHPA beads was increased with increasing pH of solution. The removal rate of Cu(II) and Pb(II) was well described by the pseudo-second-order kinetic model. The maximum removal capacity of Cu(II) and Pb(II) obtained from Langmuir isotherm were 2.58 mg/g and 12.63 mg/g, respectively. External mass transfer coefficients for the removal of Cu(II) and Pb(II) by PS-D2EHPA beads were obtained $0.61{\times}10^{-2}{\sim}5.87{\times}10^{-2}/min$ and $1.55{\times}10^{-2}{\sim}8.53{\times}10^{-2}/min$, respectively and diffusion coefficients were obtained $1.32{\times}10^{-4}{\sim}3.98{\times}10^{-4}cm^2/min$ and $1.80{\times}10^{-4}{\sim}2.28{\times}10^{-4}cm^2/min$, respectively.

Modeling and designing intelligent adaptive sliding mode controller for an Eight-Rotor MAV

  • Chen, Xiang-Jian;Li, Di
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.14 no.2
    • /
    • pp.172-182
    • /
    • 2013
  • This paper focuses on the modeling and intelligent control of the new Eight-Rotor MAV, which is used to solve the problem of the low coefficient proportion between lift and gravity for the Quadrotor MAV. The Eight-Rotor MAV is a nonlinear plant, so that it is difficult to obtain stable control, due to uncertainties. The purpose of this paper is to propose a robust, stable attitude control strategy for the Eight-Rotor MAV, to accommodate system uncertainties, variations, and external disturbances. First, an interval type-II fuzzy neural network is employed to approximate the nonlinearity function and uncertainty functions in the dynamic model of the Eight-Rotor MAV. Then, the parameters of the interval type-II fuzzy neural network and gain of sliding mode control can be tuned on-line by adaptive laws based on the Lyapunov synthesis approach, and the Lyapunov stability theorem has been used to testify the asymptotic stability of the closed-loop system. The validity of the proposed control method has been verified in the Eight-Rotor MAV through real-time experiments. The experimental results show that the performance of the interval type-II fuzzy neural network based adaptive sliding mode controller could guarantee the Eight-Rotor MAV control system good performances under uncertainties, variations, and external disturbances. This controller is significantly improved, compared with the conventional adaptive sliding mode controller, and the type-I fuzzy neural network based sliding mode controller.

오행침자법(五行鍼刺法) 원리 및 임상응용에 관한 연구 - II 임상응용에 관한 연구

  • Ahn, Chang-Beohm;Min, Young-Kwang;Kim, Jeong-Eun;Moon, Hyuck-Chol;Song, Chun-Ho;Lee, Jang-Cheon;Shin, Sang-Woo
    • Journal of Pharmacopuncture
    • /
    • v.11 no.3
    • /
    • pp.33-45
    • /
    • 2008
  • Objective: To review the clinical basis of the Sa-Ahm 5 Element acupuncture originated about 360 years ago, papers and books were researched. Methods: Total of 58 books and papers ranging from ancient Huang Di nei jing to modern Bio Medical Acupuncture for Pain Management were investigated to study the clinical practice of it. Results: It could be practiced differently depending upon the viewpoints of diagnosis. They are ranging from theories of the greater-less of Yin and Yang, 7 emotions, organs- visceras, 8 diagnostic criteria, and pulse diagnosis to meridian circulation. Conclusions: It needs to be set clinical guidelines by which to practice Sa-Ahm acupuncture though it is nowadays mostly-used method in accordance with practitioner's viewpoints.

Effect of the Boost Pressure on Thermal Stratification on HCCI Engine Using Multi-Zone Modeling (Multi zone Modeling을 이용한 흡기관내의 과급이 온도성층화를 갖는 예혼합압축자기착화엔진에 미치는 영향에 관한 연구)

  • Kwon, O-Seok;Lim, Ock-Taeck
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.33 no.4
    • /
    • pp.248-254
    • /
    • 2009
  • The HCCI engine is a next generation engine, with high efficiency and low emissions. The engine may be an alternative to SI and DI engines; however, a pressure rise rate is a major limitation for high load range and power reduction. Recently, we were able to reduce the pressure rise rate using thermal stratification. Nevertheless, this was insufficient to produce high power. In this study, the reduction of the pressure rise rate using thermal stratification was confirmed and the HCCI engine power was increased using the boost pressure. The rate and engine power were produced by CHEMKIN and modified SENKIN. As a result of increasing the boost pressure, a higher IMEP was attained while the pressure rise rate increased only slightly in the HCCI with thermal stratification.

Precision of the milled full-arch framework fabricated using pre-sintered soft alloy: A pilot study

  • Woo, Hyun-Wook;Cho, Sung-Am;Lee, Cheong-Hee;Lee, Kyu-Bok;Cho, Jin-Hyun;Lee, Du-Hyeong
    • The Journal of Advanced Prosthodontics
    • /
    • v.10 no.2
    • /
    • pp.128-131
    • /
    • 2018
  • PURPOSE. This study aimed to evaluate the marginal discrepancy of full-arch frameworks in implant-supported prostheses fabricated using pre-sintered soft alloy (PSA). MATERIALS AND METHODS. Full-arch metal frameworks were fabricated on the edentulous implant model using casting alloy (CA), fully-sintered hard alloy (FHA), and PSA (n = 4 in each group). To evaluate the misfit of the framework to the abutments, the absolute marginal discrepancy (AMD) values of the frameworks were measured in cross-sectional images that had been drawn as part of the triple-scan protocol. The AMD values were compared among the tested alloy groups using the Kruskal-Wallis test, with a post hoc Mann-Whitney U test (${\alpha}=.05$). RESULTS. The FHA and PSA groups showed lower marginal discrepancies than the CA group (P<.001). However, the FHA group did not differ significantly from the PSA group. CONCLUSION. Soft alloy milling is comparable to hard alloy milling, and it is more precise than casting in terms of the marginal fit of implant-supported, full-arch prostheses.

Damage detection on output-only monitoring of dynamic curvature in composite decks

  • Domaneschi, M.;Sigurdardottir, D.;Glisic, B.
    • Structural Monitoring and Maintenance
    • /
    • v.4 no.1
    • /
    • pp.1-15
    • /
    • 2017
  • Installation of sensors networks for continuous in-service monitoring of structures and their efficiency conditions is a current research trend of paramount interest. On-line monitoring systems could be strategically useful for road infrastructures, which are expected to perform efficiently and be self-diagnostic, also in emergency scenarios. This work researches damage detection in composite concrete-steel structures that are typical for highway overpasses and bridges. The techniques herein proposed assume that typical damage in the deck occurs in form of delamination and cracking, and that it affects the peak power spectral density of dynamic curvature. The investigation is performed by combining results of measurements collected by long-gauge fiber optic strain sensors installed on monitored structure and a statistic approach. A finite element model has been also prepared and validated for deepening peculiar aspects of the investigation and the availability of the method. The proposed method for real time applications is able to detect a documented unusual behavior (e.g., damage or deterioration) through long-gauge fiber optic strain sensors measurements and a probabilistic study of the dynamic curvature power spectral density.

Development of a Far Field type Megasonic for Nano Particle Removing (나노입자 제거용 Far Field 메가소닉 개발)

  • Lee, Yanglae;Kim, Hyunse;Lim, Euisu
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.11
    • /
    • pp.1193-1201
    • /
    • 2013
  • Improved far field type(improved type) megasonic applicable to the cleaning equipment of single wafer processing type has been developed. In this study, to improve the uniformity of acoustic pressure distribution(APD), we utilize far field with relatively uniform APD, piezoelectric ceramic with a triangle hole in its center to prevent standing wave resulted from radial mode, and reflected wave from the wall of waveguide. On the basis of these methods, two analysis models of improved type were designed to which piezoelectric ceramic of different shape of electrode attached, and APD were analyzed by means of finite element method, and then one of them was selected by analysis results, finally, the selected model was fabricated. Test results show that the fabricated is better in the uniformity of APD than the imported and the conventional, also the fabricated shows high particle removal efficiency of 92.3% using DI water alone as a cleaning solution.

Development of Auditory Evaluation Scale in Automobile Engine Sound (자동차 엔진음의 청각 감성 평가 척도 개발)

  • Kim, Wonjoon
    • Journal of Korean Society for Quality Management
    • /
    • v.48 no.3
    • /
    • pp.409-420
    • /
    • 2020
  • Purpose: The purpose of this study is to develop a measurement scale for evaluating the auditory affect of automobile engine sounds. Methods: In order to collect affective vocabulary, literature review, user tests, and expert interviews were conducted. Affective vocabulary related to automobile engine sounds was selected through three methods. To develop the evaluation scale, open/close card-sorting and expert interview-based survey method was used. Results: The results of this study are as follows; In order to select the main affective vocabulary from the collected vocabulary, 39 vocabularies with a frequency of 5 or higher were selected as vocabulary expressing the main auditory affect of automobile engine sounds. Each affective vocabulary is divided into three di- mensions, it was confirmed that the conceptual model for the auditory affect of automobile engine sounds is composed of three levels: intuitive, descriptive, and evaluative of hierarchical structure. As a result of the study, four indices of intuitive dimension, seven indices of descriptive dimension, and one index of evaluative dimension were derived from the evaluation scale of the auditory affect in an automobile engine sound. Conclusion: The auditory evaluation scale developed in this study can be used to systematically measure and evaluate the auditory affect of automobile engine sounds.

In-Vitro Refolding of PEGylated Lipase (PEGylation된 Lipase의 In-Vitro 재접힘)

  • Kim, Min-Young;Kwon, Jin-Sook;Lee, Eun-Kyu
    • KSBB Journal
    • /
    • v.20 no.5 s.94
    • /
    • pp.338-340
    • /
    • 2005
  • Covalent modification of a protein with polyethylene glycol (PEG) has become one of the most widely used and well established drug enhancement strategies in the biopharmaceutical industry. The general benefits enjoyed by PEGylation, such as prolonged serum half-lives or reduced immunogenicity in vivo, are well known. By now the PEGylation process has been performed with purified proteins, and it is required to recover the desired PEGylate by a multi-step purification process. The ultimate aim of our research is to develop an integrated process of PEGylation and in vitro refolding starting with inclusion body material. For this, we investigated the feasibility that a protein could be PEGylated under a denaturing condition and also the PEGylated proteins could be refolded correctly. Using lipase as a model protein, we found that it was PEGylated in the presence of 8M urea and that the PEG molecules covalently attached to lipase did not appear to hinder its refolding.

A SMA-based morphing flap: conceptual and advanced design

  • Ameduri, Salvatore;Concilio, Antonio;Pecora, Rosario
    • Smart Structures and Systems
    • /
    • v.16 no.3
    • /
    • pp.555-577
    • /
    • 2015
  • In the work at hand, the development of a morphing flap, actuated through shape memory alloy load bearing elements, is described. Moving from aerodynamic specifications, prescribing the morphed shape enhancing the aerodynamic efficiency of the flap, a suitable actuation architecture was identified, able to affect the curvature. Each rib of the flap was split into three elastic elements, namely "cells", connected each others in serial way and providing the bending stiffness to the structure. The edges of each cell are linked to SMA elements, whose contraction induces rotation onto the cell itself with an increase of the local curvature of the flap airfoil. The cells are made of two metallic plates crossing each others to form a characteristic "X" configuration; a good flexibility and an acceptable stress concentration level was obtained non connecting the plates onto the crossing zone. After identifying the main design parameters of the structure (i.e. plates relative angle, thickness and depth, SMA length, cross section and connections to the cell) an optimization was performed, with the scope of enhancing the achievable rotation of the cell, its ability in absorbing the external aerodynamic loads and, at the same time, containing the stress level and the weight. The conceptual scheme of the architecture was then reinterpreted in view of a practical realization of the prototype. Implementation issues (SMA - cells connection and cells relative rotation to compensate the impressed inflection assuring the SMA pre-load) were considered. Through a detailed FE model the prototype morphing performance were investigated in presence of the most severe load conditions.