• Journal of the Semiconductor & Display Technology
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• v.19 no.1
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• pp.79-84
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• 2020

Unlike a printing process, it is difficult to pattern organic thin films in the longitudinal (coating) direction using a coating process. In this paper, we have investigated the feasibility of patterning organic thin films using needles. To this end, we have slot-coated an aqueous poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) solution in the form of a fine stripe or large area and then applied the dual needle; one for discharging the main solvent of the underlying thin film and the other for sucking the dissolved thin film. We have found that the pattern width and depth increase as the moving speed of the plate decreases. However, it is observed that the sidewall slope is very gentle (the length of the slope is of the order of 200 ㎛) due to the fact that the discharged main solvent is widely spread and then isotropic etching occurs. With this scheme, we have also demonstrated that a fine stripe can be obtained by scanning the dual needle closely. To demonstrate its applicability to solution-processable organic light-emitting diodes (OLEDs), we have also fabricated OLED with the patterned PEDOT:PSS stripe and observed the insulation property in the strong light-emitting stripe.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.591-592
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• 2010

• Laser Solutions
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• v.15 no.3
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• pp.1-6
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• 2012

The friction force of patterned needle in elastomer have been investigated to verify the application for bio and plastic industry. The micro pattern on the needle surface were prepared by 266 nm, 20 ns laser and 800 nm, 220 fs laser, which were able to generate the different surface roughness. The friction force was measured by the load cell of 10 N capacity. As the results, the friction force of no patterned needle is almost constant during the needle penetrates the silicone rubber sample. However, the needle having asperities shows the variation of the friction force. The higher the surface roughness is, the smaller the friction force is until the surface roughness is very high. In our experiment conditions, the reduction of the friction force by 20 % compared to no pattern needle was achieved with straight and $50{\mu}m$ discrete line generated by 266 nm, 20 ns laser.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.509-509
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• 2011

Superhydrophobic surfaces on alloyed steels were fabricated with a non-conventional method of plasma etching and subsequent water immersion procedure. High aspect ratio nanopatterns of nanoflake or nano-needle were created on the steels with various Cr content in its composition. With CF4 plasma treatment in radio-frequence chemical vapor deposition (r.-f. CVD) method, steel surfaces were etched and fluorinated by CF4 plasma, which induced the nanopattern evolution through the water immersion process. It was found that fluorine ion played a role as a catalyst to form nanopatterns in water elucidated with XPS and TEM analysis. The hierarchical patterns in micro- and nano scale leads to superhydrophobic properties on the surfaces by deposition of a hydrophobic coating with a-C:H:Si:O film deposited with a gas precursor of hexamethlydisiloxane (HMDSO) with its lower surface energy of 24.2 mN/m, similar to that of curticular wax covering lotus surfaces. Since this method is based on plasma dry etching & coating, precise patterning of surface texturing would be potential on steel or metal surfaces. Patterned hydrophobic steel surfaces were demonstrated by mimicking the Robinia pseudoacacia or acacia leaf, on which water was collected from the humid air using a patterned hydrophobicity on the steels. It is expected that this facile, non-toxic and fast technique would accelerate the large-scale production of superhydrophobic engineering materials with industrial applications.

• Journal of Fashion Business
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• v.2 no.4
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• pp.102-111
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• 1998

The purpose of this study is to present the basic material for the competitive, high-quality products by analyzing employees' attitude toward their job and some factors which influence the enhancement of productivity, education of workers, and facilities. This project was mainly conducted the conditions of women's wear manufacturing industries in Taegu by interviewing 143 employees in the sewing department. The result of this dissertation can be summarized as follows; 1. When it comes to the division of task in the sewing department, one team is composed of chairpersons (33.5%), assistant members (27.4%) and sub-assistant members (26.6%). The inspection of commodities as well as the enhancement of work on ironing for elaboration was divided as completion (12.6%) and finally the forms of task were made up of design sampling team (49%) and contracting team (51%). 2. Among the needle workers, as many as 60% employees had received technical education, which was by means of being passed down from the predecessors (81.6%). In terms of the period of education, from 2 to 5 years topped the list. The contents of education comprise patterning, sewing (65.2%) and ironing (20.3%). 3. The department of design takes charge of the report on working directions up to 88.2% and the working directions were used by 69.9 % of technicians. The directors of working conditions and methods were chiefs of designing department (37.7%) and those of sewing department (30.8%). The factors of defective goods were low-quality materials (50.0%), the deficiency in skills of workers. In terms of methods for preventing defects, technical education of workers, standardization of task and investment for factory automation were suggested. 4. As for their perception of present work, most of employees (80%) look upon it as a way of earning a living and 11% of them wanted to derive many things from their work. 59.2% of workers were satisfied with the product. When it comes to the incentive system provided by company, 67.0% responsed that it was not bad, and 23.9% evaluated it as 'satisfactory'.