• Title/Summary/Keyword: Two stage approach

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Recovering the Energy Potential of Sewage as Approach to Energy Self-Sufficient Sewage Treatment (하수처리장 에너지 자립화를 위한 하수 에너지 잠재력 회수 기술)

  • Bae, Hyokwan
    • Journal of Korean Society on Water Environment
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    • v.34 no.1
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    • pp.121-131
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    • 2018
  • Domestic sewage treatment plants (STPs) consume about 0.5 % of total electric energy produced annually, which is equivalent to 207.7 billion Korean won per year. To minimize the energy consumption and as a way of mitigating the depletion of energy sources, the sewage treatment strategy should be improved to the level of "energy positive". The core processes for the energy positive sewage treatment include A-stage for energy recovery and B-stage for energy-efficient nitrogen removal. The integrated process is known as the A/B-process. In A-stage, chemically enhanced primary treatment (CEPT) or high rate activated sludge (HRAS) processes can be utilized by modifying the primary settling in the first stage of sewage treatment. CEPT utilizes chemical coagulation and flocculation, while HRAS applies returned activated sludge for the efficient recovery of organic contents. The two processes showed organic recovery efficiencies ranging from 60 to 70 %. At a given recovery efficiency of 80 %, 17.3 % of energy potential ($1,398kJ/m^3$) is recovered through the anaerobic digestion and combustion of methane. Besides, anaerobic membrane bioreactor (AnMBR) can recover 85% of organic contents and generate $1,580kJ/m^3$ from the sewage. The recovered energy is equal to the amount of energy consumption by sewage treatment equipped with anaerobic ammonium oxidation (ANAMMOX)-based B-stage, $810{\sim}1,620kJ/m^3$. Therefore, it is possible to upgrade STPs as efficient as energy neutral. However, additional novel technologies, such as, fuel cell and co-digestion, should be applied to achieve "energy positive" sewage treatment.

ONE-STAGE RECONSTRUCTION OF PRIMARY BILATERAL CLEFT LIP; A CASE REPORT (일차 양측성 구순열의 일단계 재건에 대한 증례보고)

  • Lim, Seok-Kyun;Yeo, Hwan-Ho;Kim, Young-Kyun;Kim, Su-Gwan;Seo, Jae-Hoon;E, Gi-Hyug;Lee, Byung-Joon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.18 no.3
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    • pp.366-370
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    • 1996
  • Bilateral cleft lip reconstruction can be performed in one-or two-stages. The choice depends on the surgeon's proficiency and experience. However the type and severity of the cleft must be considered. Complete or incomplete symmetric, bilateral clefts in which the premaxilla is within the alveolar arch or slightly protruded can be successfully treated with simultaneous lip reconstruction on both sides. There are some advantages that one-stage lip reconstruction facilitates creation of a symmetric and balanced lip, retraction of protruding premaxilla and the parent's psychologic satisfaction. However, there are some disadvantages such as micrognathia of the upper jaw by severe scar formation and poor adaptation of flap margins by severe tension. The surgeon must be able to judge and exploit the advantages offered by one-stage approach. We present the case report of one-stage reconstruction of primary bilateral cleft lip with literature reviews.

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Development of Artificial Intelligence Modeling System for Automated Application of Steel Margin in Early Modeling Process using AVEVA Marine (AVEVA Marine 강재마진의 선모델링 자동반영을 위한 인공지능 모델링 시스템 개발)

  • Kim, Nam-Hoon;Park, Yong-Suk;Kim, Jeong-Ho;Kim, Yeon-Yong;Chun, Jong-Jin;Choi, Hyung-Soon
    • Special Issue of the Society of Naval Architects of Korea
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    • 2013.12a
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    • pp.35-41
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    • 2013
  • Nowadays, automated modeling system for steel margin based on interactive user interface has been developed and applied to the production design stage. The system could increase design efficiency and minimize human error owing to recent CAD technique. However, there has been no approach to the pre-nesting design stage at all in early modeling process especially where ship model should be handled at more than two design stages using AVEVA Marine. A designer of the design stage needs artificial intelligence system beyond modeling automation when 3D model must be prepared in early modeling process using AVEVA Marine because they have focused on 2D nesting traditionally. In addition, they have a hard time figuring out the model prepared in previous design stage and modifying the model for steel purchase size in early modeling process. In this paper, artificial intelligence modeling system for automated application of steel margin in early modeling process using AVEVA Marine is developed in order to apply to the pre-nesting design stage that can detect effective segments before a calculation to find if a segment locates near block butt boundaries by filtering noise segments among lines, curves and surface intersections based on IT big data analysis.

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Adjuvant Chemotherapy and Prognostic Factors in Stage II Colon Cancer - Izmir Oncology Group Study

  • Kucukzeybek, Yuksel;Dirican, Ahmet;Demir, Lutfiye;Yildirim, Serkan;Akyol, Murat;Yildiz, Yasar;Bayoglu, Ibrahim Vedat;Alacacioglu, Ahmet;Varol, Umut;Salman, Tarik;Yildiz, Ibrahim;Can, Huseyin;Tarhan, Mustafa Oktay
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.6
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    • pp.2413-2418
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    • 2015
  • Background: Although adjuvant chemotherapy is a standard treatment in stage III colon cancer, its benefit is not as clear for stage II patients. In this retrospective analysis, we aimed to evaluate the survival of patients with low-risk stage II colon cancer, the efficacy of adjuvant chemotherapy in high-risk stage II colon cancer patients, and prognostic factors in stage II disease. Materials and Methods: One hundred and seventeen patients who were diagnosed with stage II colon cancer between January 2006 and December 2011 were included in the study. Patients were stratified into two groups as being low-risk and high-risk according to risk factors for stage II disease. Adjuvant 5-fluorouracil-based chemotherapy were administered to the patients with risk factors. Results: Ninety-four patients were treated with adjuvant chemotherapy due to high risk factors and 23 were monitored without treatment. Median follow-up time was 43 months. In terms of disease free survival and overall survival, adjuvant chemotherapy did not provide a statistically significant difference. Univariate analysis demonstrated that bowel obstruction was the major risk factor for shortened disease-free survival, while bowel perforation and perineural invasion were both negative prognostic factors for overall survival. Conclusions: The recommendation of adjuvant chemotherapy for stage II colon cancer is not clear. In our study, it was found that adjuvant chemotherapy did not contribute to survival in high-risk stage II patients. Due to the fact that prognosis of stage II patients is good, many more patients will be needed for statistically significant differences in survival. Adjuvant chemotherapy containing 5 fluorouracil is being used to high-risk stage II patients although it is not a standard treatment approach.

Analysis of Impulse Turbine for Wave Energy Conversion Using CFD Method (수치해석을 이용한 파력발전용 임펄스 터어빈의 성능해석)

  • Hyun, Beom-Soo;Moon, Jae-Seung
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.10a
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    • pp.81-86
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    • 2003
  • This paper deals with the performance analysis and design of impulse turbine for OWC type wave energy plant. Numerical analysis was performed using a commercially-available software FLUENT. This parametric study includes the variation of several important parameters such as the number and shape of blades, hub ratio and tip clearance. Since parametric study at various flow coefficients requires considerable amount of computing tim, two-dimensional analysis was employed to find out optimum principal particulars in rather simple manner. Full three-dimensional calculation was also performed for several test cases to confirm the validity of two-dimensional approach. Up to the present stage, tentative result is well demonstrating the usefulness of 2-D analysis.

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A Study on a RAM-Based Model for Integrated Automatic Manufacturing System Design and Performance Evaluation (RAM 을 고려한 복합 생산시스템의 최적설계 및 평가방안의 연구)

  • Hwang, Heung-Suk
    • Journal of Korean Institute of Industrial Engineers
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    • v.21 no.1
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    • pp.17-32
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    • 1995
  • The objective of this study is to develop a general design and performance evaluation model for the system designers in the initial design phase of the integrated automatic manufacturing system based on the RAM(Reliability, Availability and Maintainability) and life cycle cost(LCC). The methodology proposed in this research includes the following two stages. First, a deterministic approach to the solution of optimal work station arrangement for the initial system configuration is considered under the assumption that the system availability is one(no failure and maintenance), and then a stochastic simulation model based on RAM and LCC is developed. Using the results of these two stage simulation, a system performance index(SPI) was developed for the performance evaluation of the proposed system. Also a computer program is developed.

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Analysis of Impulse Turbine for Wave Energy Conversion Using CFD Method (수치해석을 이용한 파력발전용 임펄스 터어빈의 성능해석)

  • HYUN BEOM-SOO;MOON JAE SEUNG
    • Journal of Ocean Engineering and Technology
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    • v.18 no.5
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    • pp.1-6
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    • 2004
  • This paper deals with the performance analysis and design of impulse turbine for owe type wave energy plant. Numerical analysis is performed using a commercial software FLUENT. This parametric study includes the variation of several important parameters, such as the number and shape of blades, hub ratio, and tip clearance. Since parametric study at various flow coefficients requires a considerable amount of computing time, two-dimensional analysis is employed to find out optimum principal particulars. Full three-dimensional calculations are also performed for several test cases, in order to confirm the validity of the two-dimensional approach. Up to the present stage, tentative results are demonstrated the usefulness of 2-D analysis.

Neural network-based generation of artificial spatially variable earthquakes ground motions

  • Ghaffarzadeh, Hossein;Izadi, Mohammad Mahdi;Talebian, Nima
    • Earthquakes and Structures
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    • v.4 no.5
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    • pp.509-525
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    • 2013
  • In this paper, learning capabilities of two types of Arterial Neural Networks, namely hierarchical neural networks and Generalized Regression Neural Network were used in a two-stage approach to develop a method for generating spatial varying accelerograms from acceleration response spectra and a distance parameter in which generated accelerogram is desired. Data collected from closely spaced arrays of seismographs in SMART-1 array were used to train neural networks. The generated accelerograms from the proposed method can be used for multiple support excitations analysis of structures that their supports undergo different motions during an earthquake.

EXercise Prescription of A.M.I. Recovery stage (심근경색 회복기의 운동처방)

  • Lim, Sung-Soo
    • Journal of Korean Physical Therapy Science
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    • v.5 no.4
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    • pp.751-761
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    • 1998
  • The A.M.I(acute myocardiac Infarction) treated in Rehabilitation programs May be divided Into three general types, 1. mechanlcal derangement. 2. Increased resistance to blood flow. 3. decreased Energy production. in each case the heart Will be Limited in its ability to respond. to the demands of metabolic activites. cardiac rehabilitation programs following myocardiac infarction are of two general types:acute and delayed. There are fundamental differences in the philosophies, pathophilogical concepts, and psycosocial values in the two approach. both programs asplre to protect the patient through the period of Maximal risk and then safely restore him to a near normal home life and appropriate vocatlonal activity. Both programs assume that physical activity and emotional stress. increase the work of the heart and with it increase the likefood of venticular fibillation

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Constructing Container Shipping Networks with Empty Container Repositioning among Calling Ports - a Genetic Algorithm Approach

  • Shintani, Koichi;Imai, Akio;Nishmura, Etsuko;Papadimitriou, Stratos
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.157-164
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    • 2006
  • This paper addresses the design of container liner shipping service networks by explicitly taking into account empty container repositioning and container fleet size. Two key and interrelated issues of deployments of ships and containers are usually treated separately by most existing studies on shipping network design. In this paper, both issues are considered simultaneously. The problem is formulated as a two-stage problem: the upper-problem being formulated as a Knapsack problem and the lower-problem as a Flow problem. A genetic algorithm based heuristic is developed for the problem. Through a number of numerical experiments that were conducted it was shown that the problem considering empty container repositioning provides a more insightful solution than the one without.

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