• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.331-341
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• 2018

Hazardous air pollutants(HAPs) in the atmosphere are regulated as major air pollutants in Korea by the Air Pollution Control Act. In order to manage and control HAPs, accurate standards, which are traceable to the International System of Units(SI), are required. In this study, primary standard gas mixtures(PSMs) of volatile organic compounds(VOCs) which are specified as HAPs were developed at $1{\mu}mol/mol$ levels. The selected fourteen VOCs include Benzene, Toluene, Ethylbenzene, m-Xylene, Styrene, o-Xylene, Chloroform, 1,1,2-Trichloroethane, Trichloroethylene, Tetrachloroethylene, 1,1-Dichloroethane, Carbon tetrachloride, 1,3-Butadiene, and Dichloromethane. The HAPs PSMs were gravimetrically prepared in aluminum cylinders and their consistency was verified within the relative expanded uncertainty of 0.71% (k=2). Potential adsorption loss onto the internal surface of cylinders was estimated by cylinder-to-cylinder division method. No adsorption loss was observed within the uncerainty of 0.53%. The long-term stability of the HAPs PSMs was evaluated comparing with freshly prepared HAPs PSMs. The HAPs PSMs were stable for one year within the uncertainty of 0.38%. The final uncertainty of the PSMs was determined by combining the preparation uncertainty, verification uncertainty, and stability uncertainty. Finally, traceable and stable HAPs PSMs at $1{\mu}mol/mol$ levels were developed with the uncertainty of less than 0.76% in high-pressure aluminum cylinders.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.27-30
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• 2022

The plasma process, which has many advantages in terms of efficiency and environment compared to conventional process methods, is widely used in semiconductor manufacturing. Plasma Sheath is a dark region observed between the plasma bulk and the chamber wall surrounding it or the electrode. The Plasma Sheath Monitoring Sensor (PSMS) measures the difference in voltage between the plasma and the electrode and the RF power applied to the electrode in real time. The PSMS data, therefore, are expected to have a high correlation with the state of plasma in the plasma chamber. In this study, a model for predicting the state of nitrogen ions in the plasma chamber is training by a deep learning machine learning techniques using PSMS data. For the data used in the study, PSMS data measured in an experiment with different power and pressure settings were used as training data, and the ratio, flux, and density of nitrogen ions measured in plasma bulk and Si substrate were used as labels. The results of this study are expected to be the basis of artificial intelligence technology for the optimization of plasma processes and real-time precise control in the future.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.705-708
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• 1991

Novel polysilamethylenosilanes (PSMS) were prepared by Wurtz type co-condensation of various mixtures of 2,4,4,6-tetrachloro-2,6-dimethyl-2,4,6-trisilahept ane (TSH) and dimethyldichlorosilane (D). When TSH was incorporated more than 25 mole%, PSMS polymers were soluble in common organic solvents probably due to the polycarbosilane linkage brought from TSH. The molecular weights of the polymer were measured by gel permeation chromatography and showed higher molecular weight with high TSH content. The thermal gravimetric residues increased as TSH contents increased. These properties suggested that PSMS polymers could be useful as ceramic precursors for silicon carbide.

• Journal of Korean Society for Quality Management
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• v.31 no.4
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• pp.184-193
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• 2003

PL has been developed centering around England and America. Recently many countries are introducing PL system changing the world a single economic bloc based on the rapid development of Technology and Economy. This paper is studied with related literatures and theses, organizational consulting cases within the framework of the firm as the central operating bodies of PL system. In the past, Some papers about System Integration which was operated as a same Certificate System and enacted in a single organization, was studied and presented. But most of papers was a theoretical study related model and conception. In this situation Government supports PSMS of a single system at government expense to 100­200 companies for improving organizational confrontation ability of PL this year. This paper proposed a design and effect of Integration system model based on the analysis of ISO 9001：2000, KS, PSMS and ISO 14001. The integrated system has the following three distinctions. Firstly, KS is a national establishment, national leading certification and forcing standard. Secondly, ISO 9001：2000 and ISO 14001 are an international organization's establishment, non­official certification and optional standard. Finally, PSMS isn't a national law and forcing matter. And it isn't the concept of certification but the operational system by itself. Also if a lawsuit by defect is happened, it is very dangerous. This paper, which is integrated by four management systems and has many consulting cases, is the first in this department and is different from others. Also If people has the basic knowledge about management system, they can directly connect it to the organizational system according to this paper's guidance. It is very good result in this study because the law of PL is executed now.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.115-122
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• 2021

Phenol-soluble modulins (PSMs) are responsible for regulating biofilm formation, persister cell formation, pmtR expression, host cell lysis, and anti-bacterial effects. To determine the effect of psm deletion on methicillin-resistant Staphylococcus aureus, we investigated psm deletion mutants including Δpsmα, Δpsmβ, and Δpsmαβ. These mutants exhibited increased β-lactam antibiotic resistance to ampicillin and oxacillin that was shown to be caused by increased N-acetylmannosamine kinase (nanK) mRNA expression, which regulates persister cell formation, leading to changes in the pattern of phospholipid fatty acids resulting in increased anteiso-C15:0, and increased membrane hydrophobicity with the deletion of PSMs. When synthetic PSMs were applied to Δpsmα and Δpsmβ mutants, treatment of Δpsmα with PSMα1-4 and Δpsmβ with PSMβ1-2 restored the sensitivity to oxacillin and slightly reduced the biofilm formation. Addition of a single fragment showed that α1, α2, α3, and β2 had an inhibiting effect on biofilms in Δpsmα; however, β1 showed an enhancing effect on biofilms in Δpsmβ. This study demonstrates a possible reason for the increased antibiotic resistance in psm mutants and the effect of PSMs on biofilm formation.

• IE interfaces
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• v.21 no.1
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• pp.18-32
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• 2008

In recent, a general trend is observed towards more customized products and shorter product life cycles in manufacturing companies. In these companies, customers often wish to influence the product they order and to get a variant of product that meets their requirements. This environment is called as a customer-oriented manufacturing companies. This paper presents a procedure of product specification management for customer-oriented manufacturing companies by using product specification framework. This framework is founded on the product specification based product structure which is made of model, specification, function, and part. Also, a product specification management system(PSMS) is implemented by using the proposed product specification framework and is a core system in product data integration system. To illustrate an utilization of the proposed framework and procedure, a case of a ship engine product is applied. As a result, PSMS reduces delivery time and improves customer relationships. Moreover, the case shows that PSMS can be used as a tool for improving inter-department coordination within a company during product life cycle.

• Journal of Korean Society for Quality Management
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• v.31 no.3
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• pp.19-36
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• 2003

The manager of manufacturing industry just not to have known what to do related to the law of product liability(PL) that was put into operation in July 1, 2002. The law of PL is a public law about defective product, which was established in order to compensate consumer's damages of property and body caused by product, to make sound society by the safety products and to take international competitiveness. But the existing civil law has been having clause that compensation to be taken is limited. The law of PL is resolving this limitations and is characterized by the easy relief from damages of defective product. The decision in the case of Green-man has been a precedent since the court sentenced the manufacturer to liability. The law of PL has been in force in 27 countries, including all of the EU countries, Japan, Philippines and China. It has been shown that the corporations which meet the Global Standard, could survive in global competition. The economic effects by the law of PL are the increase of consumers relief production cost by the lawsuits. This paper will recommend more biref method that is able to cover PSMS by use of QMS. It will make domestic corporation improve in the plan, manufacture and sale of products to meet the Global Standard.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.2
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• pp.124-131
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• 2021

In the recent business environment, risks related to product safety problems are increasing. These are arising from various factors such as increasing product and production complexity, supply chain diversification, enhanced PL (product liability) law and strengthening regulations of the government. Accordingly, ISO (international organization for standardization) published standards of PSMS (product safety management system) for suppliers such as ISO 10377 and ISO 10393. Meanwhile, the ISO 9001 QMS (quality management system) was revised in 2015, and it has established itself as an effective tool that can consistently meet the various requirements of stakeholders and promote customer satisfaction. This study aims to suggest an integration framework of QMS and PSMS based on the recent ISO international standards. To this end, firstly, the relationship between QMS and PSMS is studied based on the quality and product safety definitions, PDCA (plan-do-check-act) cycle and risk-based thinking. Secondly, the requirements of ISO 10377 and ISO 9001 are compared and classified as the common and ISO 10377 specific requirements. Finally, integration steps of two systems are suggested and guidelines that can systemize the integrated requirements are presented in the aspect of processes and documentation. This study is expected to be used as a guideline that helps companies those have already acquired QMS certification to build an international-level product safety management system early.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.463-481
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• 2022

Phosphorous (P) is considered to be one of the key essential elements demanded by crop plants. Approximately 70 - 90% of phosphatic fertilizers applied to crops are fixed in soil as Ca, Fe, and Al metal cations, which are insoluble and thus not readily available for plant uptake. Therefore, most soils are deficient in plant available P. This is usually rectified by applying phosphate fertilizers continuously, although this is not economically viable or environmentally acceptable. The present paper reviews the mechanisms involved with phosphate solubilization and mineralization by phosphate solubilizing microorganisms (PSMs) with the associated factors that determine the success. PSMs are effectively involved in mediating the bioavailability of soil P. Their contribution includes mineralization of organic P solubilization of inorganic P minerals, and storing sizable amounts of P in biomass through different mechanisms such as the production of organic and inorganic acids, H₂S, siderophores, exopolysaccharides, and production of enzymes such as phosphatases, phytase, and phosphonatases/C-P lyases, which are capable of chelating the metal ions, forming complexes, and making plant available P. PSMs manifest a wide range of metabolic functions in different environments, resulting in significantly higher plant growth, enhanced soil properties, and increased biological activities. Therefore, development of bio-inoculants with efficient novel PSM strains and further investigations on exploring such strains from diverse ecological niches with multifunctional plant-growth-promoting traits are needed.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.3
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• pp.320-328
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• 2016

Among biogenic volatile organic compounds (BVOCs) in the natural ecosystem, monoterpenes, along with isoprene, play important roles in atmospheric chemistry and make significant impacts on air pollution and climate change, especially due to their contribution to secondary organic aerosol production and photochemical ozone formation. It is essential to measure monoterpene concentrations accurately for understanding their oxidation processes, emission processes and estimation, and interactions between biosphere and atmosphere. Thus, traceable calibration standards are crucial for the accurate measurement of monoterpenes at ambient levels. However, there are limited information about developing calibrations standards for monoterpenes in pressured cylinders. This study describes about developing primary standard gas mixtures (PSMs) for monoterpenes at about 2 nmol/mol, near ambient levels. The micro-gravimetric method was applied to prepare monoterpene (${\alpha}$-pinene, 3-carene, R-(+)-limonene, 1,8-cineole) PSMs at $10{\mu}mol/mol$ and then the PSMs were further diluted to 2 nmol/mol level. To select an optimal cylinder for the development of monoterpene PSMs, three different kinds of cylinders were used for the preparation and were evaluated for uncertainty sources including long-term stability. Results showed that aluminum cylinders with a special internal surface treatment (Experis) had little adsorption loss on the cylinder internal surface and good long-term stability compared to two other cylinder types with no treatment and a special treatment (Aculife). Results from uncertainty estimation suggested that monoterpene PSMs can be prepared in pressured cylinders with a special treatment (Experis) at 2 nmol/mol level with an uncertainty of less than 4%.