• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.657-662
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• 2012

This study was carried out to evaluate the removal rate of organic and inorganic matters from landfill leachate using pre-treatment process as coagulation and limonite adsorption, and membrane process as RO (reverse osmosis) and NF(nanofiltration). By adding limonite adsorption as pre-treatment process, about 40% of organic matters in leachate was removed through pre-treatment process and 74.7% of boron was removed after RO process without pH adjustment. The rejection rate of boron in RO process mainly depends on the pH and increased at pH value of 10. RO process was performed as two stage system adjusting pH condtion to 7 and 10 in second RO stage for boron removal. Most (>90%) of TOC, Cl- and inorganic matters as Ca was rejected in first RO stage, the residue was rejected in second RO and the rejection rate was above 97%. Considering economic efficiency of operation cost, NF substituted for the first RO and total removal rate of TOC was above 90%. Through RO system toxicity to Daphnia in leachate was removed completely.

• Membrane Journal
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• v.34 no.1
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• pp.79-86
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• 2024

The flat sheet membrane, one of the representative forms of polymeric membranes, is widely used from material research in laboratories to commercial membrane production due to its ease of fabrication. Porous polymeric flat sheet membranes used in microfiltration and ultrafiltration are mainly fabricated through phase separation processes, utilizing non-solvent-induced and vapor-induced phase separation methods. However, due to the nature of phase separation processes, variations between samples can easily occur depending on the surrounding environment and the experimenter, making it difficult to ensure reproducibility. Therefore, for scaling up and ensuring reproducibility of developed membrane fabrication technologies, there is a need for a controlled environment continuous large-area production device, such as a roll-to-roll manufacturing system. This research compared the changes in membrane characteristics due to differences in manufacturing environments when scaling up laboratory-scale fabrication technologies to roll-to-roll processes using knife and slot die coaters. By optimizing the continuous manufacturing process factors, uniformity of the membrane was ensured during large-area production.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.99-109
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• 2007

To realize process-driven management, so many companies have been launching business process managementsystems. Business process is collection of standardized and structured tasks inducing value creation of acompany. Moreover, it is recognized as one of significant intangible business assets to achieve competitiveadvantages. This research introduces a novel approach of workflow process analysis, which has more and moresignificance as process-aware information systems are spreading widely into a lot of companies, In this paper, amethodology of workflow clustering based on process similarity has been proposed. The purpose of workflowclustering is to analyze accumulated process definitions in order to assist design of new processes andimprovement of existing ones. The proposed methodology exploits measures of structural similarity of workflowprocesses.The methodology has been experimented with synthetic process models for illustrating the implicationofworkflow clustering.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.3
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• pp.1-19
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• 2002

Recently, increasing attention has been paid to building a successful software process in Information System(IS) implementation. This study establishes software process model as a key predictor of organizational performance. We propose a theoretical framework for capability maturity model derived from the Software Engineering Institute(SEI). This paper identify the process-related variables, financial performance and non-financial performance from the relevant literature and clarify the concept of software process by distinguishing between its component and determinants. We then examine the impact of software process on organizational performance. Hypotheses on software process were tested for 36 enterprises including 118 organizational units. Results indicate that software process capability may serve as a key predictor of organizational performance. Software process maturity found to be positively influenced on the financial and non-financial performance, while investment of information technology as a mediating variable not significantly affected to the performance.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.4
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• pp.1-17
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• 2014

The functions of stocking and releasing in logistics center consist of three major procedure such as receiving, shipping and stock managements. Each process includes various sub-processes which are complicatedly connected with each other. Furthermore, lots of operators execute various tasks in the different sub-processes, simultaneously. It makes difficult to standardize, monitor, and analyze the processes. This paper proposed the quantitative methodology using process mining approach to discover and analyze receiving and shipping processes. For this purpose, the PDA operation log data is analyzed to build a realistic process model. The deduced model has been compared with official process model. In addition, task assignment and social networks analysises are carried out by utilizing process mining tools. Also, it has been proposed how to improve the processes with the analytical simulation model based on the results of process mining.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.1142-1149
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• 2003

Various organizational factors effect successful implementation of IT enabled business transformation. Among them, the most critical success factor is deemed to overcoming change management problem. Lots of studies have been made on Implementation methodologies and business process formalizations to encourage organizational members to accept new business process changes. However, the logic or process redesign still depends on qualitative problem solving techniques mostly depending on basically human intuition such as brainstorming. cause-and-effect analysis. and so on. In this paper, we focused on developing analytic framework to design to-be business process structure. which can complement qualitative problem solving procedures. With effective use of IT as an enabler, we provide algorithmic framework applicable to designing various business process changes such as process automation, business process resequencing, and more radical process integration. The framework follows dynamic programming approach in the literature, which is based on the decision making paradigm of organizations to abstract business processes as quantitative decision models. As such, our research ran fill the gap of limited development of theory based analytic methodologies for business process design, by providing objective rationale to reach the consensus among the organizational members including senior management.

• Proceedings of the Safety Management and Science Conference
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• 2012.04a
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• pp.573-577
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• 2012

Based on latest research, the parametric quality statistics cannot be used in non-normal process with demand pattern of many-variety and small-volume, since it involves extremely small sample size. The research proposes nonparametric quality statistics according to the number of lot or batch in the non-normal process. Additionally, the nonparametric Process Capability Index (PCI) is used with 14 identified non-normal distributions.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.05a
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• pp.16.2-16.2
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• 2006

• ETRI Journal
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• v.27 no.1
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• pp.122-125
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• 2005

A polymer-based planar-lightwave-circuit-type variable optical attenuator (VOA) was fabricated using a hot embossing process. With an optimized one-step embossing process, forty micro-channels for the guidance of light were defined on a polymer thin film with an accuracy of ${\pm}0.5{\mu}m$. The fabricated polymeric thermo-optic VOA shows 30 dB attenuation with 110 mW electrical input power at $1.55{\mu}m$. The rise and fall times are less than 5 ms.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.600-600
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• 2003