• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.91-94
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• 2008

In this paper, we searched for impact factors by brainstorming and calculated the weights of them using the Analytic Hierarchy Process(AHP) method in order to develop energy technology strategy for the future. AHP is a useful method for evaluating multi-criteria decision making problems. We selected 3 criteria(possibility of success for developing technology, application of the technology, technical spin-off) and 10 sub-criteria. According to the result in this study, the most important sub-criterion is the possibility of commercialization, the second is the possibility of developing the fundamental technology, and the third is the possibility of convergence technology. The other side, the lowest important sub-criterion is the difference of technical standards as compared with advanced countries.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.1-6
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• 2002

In order to simulate the actual wet-end process in papermachine, RDA, a novel handsheet former, was used and following results were obtained. While the addition of polyelectrolytes gives significant effect on fiber flocculation, increase of stock consistency influenced on the formation of RDA sheets greatly. In particular, the consistency increase from 0.3 % to 0.4% abruptly increased floe size of RDA sheet and it results in severe deterioration of paper strength. Stock consistency, therefore, should be regarded as the most important factor in the formation simulation with RDA and should be controlled as the first sequence of tuning the operating conditions of RDA to simulate correctly the target machine paper's formation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.73-85
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• 1999

Yield and fracture are separated in the tensile failure of paper. Failure in the machine direction of photocopy paper is contrasted with failure in the cross-machine direction . The ratios of distortion (shape change) to dilatation (volume change) for individual elements at yield and fracture are described. The ratios of distortion to dilatation are measured and compared to predicted values of the strain energy density theory. To evaluate the effect of the angle from the principal material direction on the strain energy density theory. To evaluate the effect of the angle from the principal material direction on the strain energy density factor, samples are prepared from machine direction to cross-machine direction in 15 degree intervals. the strain energy density of individual elements are obtained by the integration of stress from finite element analysis with elastic plus plastic strain energy density theory. Poison's ratio and the angle from the principal material direction have a great effect ion the ratio fo distortion to dilatation in paper. During the yield condition, distortion prevails over dilatation . At fracture, dilatation is at a maximum.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.35-46
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• 1999

Mathematical modeling provided a systematic analysis for the dynamic behavior of stock fluid in a paper machine pressurized headbox. Dynamic responses of liquid level, sheet basis weight and hydraulic pressure were predicted from the simulation model which represents the system. A unit step and asinusoidal wave load were considered as the input forcing functions in the headbox. Results are summarized as follows : 1. The dependence of sheet basis weight on liquid level in the pressurized-headbox was non -linear. 2. Liquid level in the head-box showed first-order lag with a unit step forcing to fluid input rate ; 3 . The amplitude of wave response of liquid level was inversely proportional to the time content for the sinusoidal input changes ; 4.Sheet basis weight showed second-order oscillating underamped responses for the step input load of flow rate ; 5. The damping factor in the second-order system was a function of air-pressure in the headbox ; and, 6. Dead-time existed in the measuring process for the headbox slice pressure.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.51-57
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• 2000

Cylinder machine usually gives more fiber orientation than fourdrinier and has limitation in machine speed because of fiber wash-off caused by centrifugal force when machine speed increases. This study aimed for the improvement of paper formation and productivity by setting an apron in vat inlet and by adjusting mould water head. Improvement of formation and increase of machine speed were achieved, which ultimately improve productivity. Installing an apron successfully decreased fiber wash-off. Fiber orientation and two-sideness of ash distribution became less severe. The proper adjustment of water head inside the cylinder mould proved to be an important factor not only in paper formation but also in decreasing paper two-sideness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.58-64
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• 2009

This study was carried out to prepare high porosity pulp for oil and air filter media from commercial grade NBKP with 6 - 20% NaOH treatment. The fiber width of NBKP remarkably decreased by NaOH pretreatment. The air permeability of the test sheet prepared from alkali-pretreated NBKP increased with increasing NaOH concentration up to 15%. The burst factor was greatly decreased by alkali pretreatment. By 15 - 20% NaOH pretreatment of NBKP, it could be possible to prepare a high porosity pulp. It seems that the high porosity of the pulp was due to a strong swelling and a great change of the cellulose crystalline lattice from cellulose I to cellulose II with NaOH treatment of NBKP. The study suggested that alkali- pretreated NBKP could be used for manufacturing oil and air filter media.

• Corrosion Science and Technology
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• v.6 no.3
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• pp.96-102
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• 2007

The resistance of the linepipe steel to hydrogen-induced cracking (HIC) and sulfide stress cracking (SSC) is very important for steel to be used in sour oil/gas environments. Welding of steels is necessary to the construction of pipe-line transporting oil/gas. In this study, HIC and SSC resistance of an electric resistance welded (ERW) steel plate which belongs to API X70 grade was evaluated by using NACE TM0284-96A and NACE TM0177-96A methods. HIC and SSC fracturing behavior was investigated by observing fractured surfaces using optical microscopy (OM) and scanning electron microscopy (SEM). It was discussed in terms of metallurgical parameters such as the distribution of primary microstructure, second phases and inclusions. Results showed that the weld joint of ERW steel is more sensitive than base metal to HIC and SSC. This is due to difference in the contribution of metallurgical parameters to HIC and SSC nucleation and propagation.

• The Journal of Information Systems
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• v.11 no.1
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• pp.1-28
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• 2002

Today, IT outsourcing has become a very important management strategy of implementing information systems in organizations. This paper investigates the risks and strategic recognition as a key factors effecting on the degree of outsourcing, Specifically the risks of outsourcing and its four components-control risk, economical risk, technical risk, relational risk-are examined to be a negative effect on the degree of outsourcing. And strategic recognition about outsourcing is examined to be a mediator factor between the risks and the degree of outsourcing. To empirically test these relationships, data are gathered from senior IT managers in 62 corporations. Results of this study show that the degree of outsourcing is strongly influenced by control risk, economical risk, relational risk. But technical risk does not influence on the degree of outsourcing. And strategic recognition about outsourcing is found that is mediator concern with the risks and the degree of outsourcing. The results indicate to provide a good framework to minimize the risks for IT outsourcing success.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1237-1244
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• 2006

This research discussed about method for basis construction of sea jacket construction. Several access ways of method for foundation construction of sea jacket construction are used. Accompany many efforts of design and build process to overcome the form of construction work and application equipment, special quality of construction and restriction and so on of sea environment in the case of pile foundation. Therefore, great many factor of sea condition, construction special quality, base condition, construction time, equipment composition, worker composition etc. shows other work form in spot at sea jacket construction process.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.5
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• pp.199-204
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• 2000

This paper presents new approaches for the calculation for the calculation of each user's wheeling prices based on the economic analysis method with focus on the postage stamp rule. The suggested postage stamp rules can overcome the following problems embedded in the conventional accounting-costs-based methods such as the volatileness of wheeling prices depending deprieciation methods, emerging the wheeling free-riders due to the difference between accounting life-time and technical life-time, price discrimination between firm and non-firm network users, etc. To solve these problems we suggest new postage stamp rules employing capital recovery factor for investment costs treatment and applying technical life-time. Furthermore, we have suggested a new formulation for non-firm wheeling users based on the wheeling energies. In the case study, the results of suggested postage stamp methodologies are compared with those of conventional approaches.