• Title, Summary, Keyword: sizing

Search Result 1,203, Processing Time 0.038 seconds

The Influence of Base Paper Sizing on Coating Penetration into Paper (원지의 사이징 특성이 도공액의 침투에 미치는 영향)

  • Kim, Bong Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.45 no.1
    • /
    • pp.21-26
    • /
    • 2013
  • The influences of heat treatment and surface sizing on coating penetration were studied using two types of commercial base papers. Dry oven was used for heat treatment and laboratory rod draw down coater was used for surface sizing and coating application. Coating penetration was evaluated by measuring the roughness of the backside of coating layer. The backside of the coating was exposed by dissolving the fibers in a cupriethylenedimine(CED) solution. The results showed that both heat treatment and surface sizing were the effective methods to increase sizing degree and to reduce coating penetration.

Computational Study of Cutting Planes for a Lot-Sizing Problem in Branch-and-Cut Algorithm (Branch-and-Cut 알고리즘에서 Lot-Sizing 문제에 대한 Cutting Planes의 전산 성능 연구)

  • Chung, Kwanghun
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.40 no.3
    • /
    • pp.23-38
    • /
    • 2015
  • In this paper, we evaluate the strength of three families of cutting planes for a lot-sizing problem. Lot-sizing problem is very basic MIP model for production planning and many strong valid inequalities have been developed for a variety of relaxations in the literature. To use three families of cutting planes in Branch-and-Cut framework, we develop separation algorithms for each cut and implement them in CPLEX. Then, we perform computational study to compare the effectiveness of three cuts for randomly generated instances of the lot-sizing problem.

Structural Sizing for Optionally Piloted PAV Preliminary Design (유무인 겸용 개인항공기(OPPAV) 개념설계를 위한 구조물 사이징)

  • Kim, Sung Joon;Lee, Seung-gyu
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.28 no.1
    • /
    • pp.83-89
    • /
    • 2020
  • Personal air vehicle (PAV) is considered by aviation engineers as a solution to provide fast urban mobility. The purpose of designing a optionally piloted PAV (OPPAV) is to provide an individual air vehicle. The airframe structure is designed with high strength carbon fiber composite to reduce the aircraft weight. This paper presents an overview of sizing process for OPPAV at the conceptual design level. It consists of load analysis, structural sizing and development of efficient design allowable values for composite material. The weight is estimated based on sizing process, including strength and stiffness requirements. The objective of this study is to present a overview of structural sizing procedure and fast tool for preliminary design phases.

Coagulation of Cationic Rosin Emulsion and its Effect on Ink Receptivity of Coating Layer (양이온성 로진 에멀션의 응결현상이 도공층의 잉크흡수성에 미치는 영향)

  • 박철웅;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.30 no.3
    • /
    • pp.74-83
    • /
    • 1998
  • The phenomenon of decrease in sizing efficiency when the stock temperature is increased is well recognized as summer sizing, and this is believed to be caused by uneven distribution of sizing agents on paper surface most often incurred by coagulation of sizing agents. When unevenly sized paper is used as coating base stock, nonuniform consolidation of the coating layer may result, which, in turn, causes uneven distribution of binder on coating surface. This causes nonuniform ink absorption to produce print mottle. In this study the effects of simple or polymeric electrolytes, storage temperature and time on the coagulation of cationic dispersed rosin size were investigated using a turbidity measurement method which was verified to correlate well with the particle size of rosin emulsion or its coagulates. Handsheets sized with rosin dispersions coagulated under various conditions were prepared and their sizing degree and coated paper properties including gloss and ink density were examined. The relationship between the sizing nonuniformity of coated papers and its ink absorption property was evaluated. Turbidity of rosin emulsion increased as the storage temperature and time were increased. Addition of simple or polymeric electrolytes caused reduction in $zeta$ -potential of the rosin dispersion and accelerated the coagulation tendency substantially. Reversion of the $zeta$ -potential of rosin dispersion, however, did not occur when coagulation was induced with simple electrolytes. On the other hand, addition of an anionic polyelectrolyte reversed the $zeta$ -potential of the flocculated rosin dispersion. This indicated that electrical double layer compaction and bridging flocculation were coagulation mechanisms for simple and polymeric electrolytes, respectively. Sizing degree decreased as coagulation of rosin was increased. Paper gloss, ink gloss and ink density were increased when sizing degree of base stock was increased most probably due to prevention of base paper swelling and increased binder migration to coating surface. This suggested that uneven printing ink density occurred when uneven sizing development was induced by coagulation of rosin particles.

  • PDF

Studies on the Printability of Hanji by Sizing and Calendering

  • Kang Jin-Ha;Seo Seung-Man;Park Seong-Cheol
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.37 no.5
    • /
    • pp.70-77
    • /
    • 2005
  • The development of printable Hanji is regarded as an important work to create a new demand of Hanji in information-oriented era. Hanji has rougher surface, huger absorption of ink and lower optical properties and printabilities than common printing papers. Improving those shortcomings of Hanji is required to be printable Hanji. Sizing and calendering have known as a way to make properties of paper good. Accordingly, this research was performed to find out useful sizing agents for reforming its drawbacks. Four sizing agents (CMC, com starch, PVA, AKD) were used in this research. The optical properties and the printabilities of sized Hanji were tested. The obtained results were as follows. Based on concentration, each sizing agent was prepared. These were CMC(0.5, 1, $1.5\%$), corn starch(1, 2, $3\%$), PVA(1, 5, $10\%$), AKD(0.5, 0.1, $0.15\%$) respectively. After sizing, we performed calendering treatment with pressure of 0.5, $1\;kgf/cm^2$. All the sizing agents and calendering treatment improved the properties of Hanji to some extent. Particularly, com starch was good for gloss. In case of printability, $1\%$ AKD with $1\;kgf/cm^2$ was recommendable for typography ink density, $3\%$ com starch with $0.5\;kgf/cm^2$, inkjet ink density, $2\%$ com starch with $0.5\;kgf/cm^2$, inkjet ink girth. PVA and AKD without calendering were counter-effective agents for inkjet ink density. Printable Hanji is required to have not only better surface strength enough to appear non-picking, higher ink density and lower show-through than base paper but also the lowest ink girth in comparison with base paper. When referring to them, efficient sizing agents were regarded as $0.1\%$ AKD with $1\;kgf/cm^2$, calender pressure, for typography printing and $2\%$ com starch with $0.5\;kgf/cm^2$, calender pressure, for inkjet printing.

Automatic Color Recognition System for Stockigt Sizing Test (II) - Application of the automatic recognition principle of red coloration for developing the novel automatic system - (스테키히트 시험용 자동발색인지 시스템 개발을 위한 기초 연구(II) -자동 발색 인지 원리를 적용한 발색 자동인지시스템-)

  • Kim, Jae-Ok;Kim, Chul-Hwan;Park, Chong-Yawl;Kwon, Oh-Chul
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.37 no.1
    • /
    • pp.73-81
    • /
    • 2005
  • Stockigt sizing test, which is readily affected by individual tester's bias as well as testing conditions in recognizing red coloration, had to be modified to improve its reliability and reproducibility. The novel testing system with the automatic recognizing program of red coloration was developed with the auxiliary equipments including an automatic liquid dispenser and a specimen shifter. The analysis program used a hue value of a droplet image in recognizing a point of time on red coloration instead of RGB values that are not similar to human perception of color. Hue was more sensitive in recognizing the red coloration of a droplet than the other two factors, Saturation and Value. During the test, the program records the time consumed up to a specific hue value of a droplet on a specimen. Differently from the conventional test, the automatic test could obtain a reliable and reproducible sizing degree with a minor error. Furthermore, the Stockigt sizing degree measured by the automatic system showed great correlations with contact angle and Hercules sizing degree. It means that such great correlations will contribute to the development of an integrated measuring system capable of predicting contact angle, surface tension, surface energy and Hercules sizing degree of paper and paperboards through the Stbckigt sizing test. It was meaningful to note that the automatic system for Stbckigt sizing test might be able to used to predict contact angle, Hercules and Cobb sizing degree, based upon the high correlation coefficients.

Sizing System for Medical Compression Stockings -Focus on Imported Medical Compression Stockings in the Korean Market- (의료용 압박스타킹의 사이즈 체계에 관한 연구 -한국 시장에서의 수입 의료용 압박스타킹을 중심으로-)

  • Do, Wol-Hee;Kim, Nam-Soon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.36 no.8
    • /
    • pp.860-874
    • /
    • 2012
  • This study provides size information on current imported medical compression stockings in Korea. A total 20 brands from 6 countries imported and sold in the Korean on-off line markets were selected for this study and the sizing system of medical compression stockings was researched. The results of this study were as follows: there were size differences among different USA brands according to product type or compression class of medical compression stockings. To establish the sizing system for medical stockings of the German brands, the basic body measurements standard was set as cA, cY, cB, cB, cC, cD, cE, cF, cG, cH, cT, lD, lG, and lT. Italian brands developed the sizing system for medical compression stockings by compression class. In the Swiss brands, size types were sub-divided as 'Normal', 'Plus', 'Short', and 'Long'. The sizing 1 were confined within very narrow limits. There were differences of the basic body measurements between Taiwan brands. The results of the comparison of the size range of the imported brands with Size Korea (KATS, 2010) by two-way size distribution shows that the sizing systems of the imported brands were unsuitable for Koreans. To enhance the suitability of the sizing system for medical compression stockings, a new sizing system for Korean adult males and females needs to be established.

Automatic Test Method of Sizing Degree by Analysis of Liquid Penetration and its Surface Behavior (액체 침투 특성과 표면 거동 분석을 이용한 사이즈도 자동측정법)

  • Lee, Ji-Young;Kim, Gyung-Chul;Kim, Chul-Hwan;Sheikh, M.I.;Park, Hyun-Jin;Kim, Sung-Ho;Sim, Sung-Woong;Cho, Hu-Seung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.44 no.2
    • /
    • pp.18-28
    • /
    • 2012
  • This study was to develop a novel automatic system for measuring St$\ddot{o}$ckigt sizing degree and contact angle at a time. The conventional methods to measure sizing degree had serious problems in obtaining significant differences according to different dosages of a sizing agent, and moreover they disclosed unique limitation due to liquid types used and tester's subjectivity. However, the newly developed system could get reproducible results through total automation of all procedures including liquid dropping, image acquisition and measurement of both St$\ddot{o}$ckigt sizing degree and contact angle. For the St$\ddot{o}$ckigt sizing test, the automatic system could measure sizing degree with more definite differences according to different dosage of AKD, compared to the conventional method. For the contact angle test, the automatic system showed a similar trend to the conventional method but had smaller contact angles due to distortion of an image focus by a sheet curl than the conventional testing machine. The problem from the image out of focus due to specimen curl will be overcome with adopting a new specimen holder for the future system.

A Study on the Appropriateness of the Current Sizing System of Infant Coveralls (시판 유아용 커버롤의 치수적합성에 관한 연구)

  • 도월희;최혜선;김은경
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.27 no.2
    • /
    • pp.277-288
    • /
    • 2003
  • The purpose of this study was to provide information on how to improve the current sizing system of infant coveralls through analysis of the present system. In order to compile the information about dissatisfaction with the appropriateness of the fit of infant coveralls, a questionnaire was administered to mothers of 241 infants (aged under 36 months) living in Seoul, and analyzed using the SPSS WIN.10.0 program. Also, the manufacturers'basic body sizes were investigated. The results of this study were as follows : 1. The results of the comparison between the manufacturers'basic body sizes and the body measurement values obtained as the physical standard of the nation(1997) show that in terms of length and hip circumference, the manufacturers'body sizes were larger. On the other hand, in the waist circumference, the manufacturers'body sizes were smaller than the national average. 2. Research on the production sizing system of domestic and international brands, showed that the sizing interval of domestic brands were 6 months, whereas the international brands were 3 months f3r infants under 12 months. 3. Concerning fit, the areas causing most dissatisfaction were: the trunk length, sleeve length, inside leg length, and neck depth. The results showed that dissatisfaction with the suitability of the sizing of current infant coveralls according to the body part differed among the groups according to the month of age.

A Study on Actual Condition of Sizing System of Women′s RTW Apparel Brands in Korea (한국 여성복 브랜드의 치수 체계 실태에 관한 연구)

  • 오설영;천종숙
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.26 no.1
    • /
    • pp.50-61
    • /
    • 2002
  • The manufacturer first identifies a target market before developing a sizing chart. A target market is specific for age or figure type. The purpose of this study is to evaluate the suitability of sizing system of women's apparel brand in Korea. For this purpose, the characteristics of the manufacture's sizing chart for jacket and skirt/pants were analyzed. For each brand, the target age of the brand and the age of consumers who preferred that bland were compared. The size charts collected from 27 women's apparel brands were analyzed and compared with Korean industrial standard sifting chart. The results of this study reviled that the body proportion in many manufacturer's sizing chart does not correspond to the body types in Korean industrial standard sizing chart. This trend was apparent for the short figure sizes made for women 155cm in height. There is a difference between the target age in brand concept and the age of consumer preferring to purchase that brand apparel. The age of fitting models usually does not correspond the customer's age. It was concluded that the age of target customer does not go well with the age of brand concept nor the fitting model age caused fit problem of the women's ready-made clothes.