• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.151-151
• /
• 2017

본 연구는 인력을 이용한 품질검사를 수행하고 있는 현장에서 불량 및 품질에 대한 신뢰성이 떨어지고 있는 현상을 해소하기 위해 자동으로 평면도를 측정하고자 하였다. 설계는 Auto CAD를 이용하였다. 평면도 측정기의 크기는 가로${\times}$세로${\times}$높이를 $1000{\times}600{\times}1800mm$로 하였다. 프레임은 $60{\times}60$ 프로파일을 이용하였고 다른 구성 부품은 SUS304 재질을 이용하였다. 측정대상을 올려놓은 상태에서 녹색 버튼을 누루면 작동되도록 되어 있다. 그림 8은 측정결과를 나타낸 것이다. 측정기는 국내업체인 데바의 모델명 EA-20N의 Air Micrometer을 사용하였으며 측정핀의 위치는 조정이 가능하도록 하였다. 평면도 측정 중 설정치수와 같이 않으면 NG 명령과 함께 부저가 울리도록 프로그램하였다. 불량이 발생하면 그림 8과 같이 나타났다. 불량 측정을 위해 측정부의 결과 값이 나타나며 불량이 발생하면 어느 위치에서 불량이 발생했는지를 알 수 있도록 하였다. 또한 결과 값은 자동으로 저장되도록 하였다. 품질확보를 위해 100EA를 측정한 결과 0.00258, 0.00259, 0.00259, 0.00263, 0.00251, 0.00286, 0.00275의 평균값을 나타냈다. 측정값의 검증은 하이트게이지로 측정한 결과 0.002 이내의 결과를 나타냈다. 따라서 본 평면도 측정기를 이용한다면 생산성 향상이 가능하여 가격경쟁력이 있다고 판단된다.

• Polymer(Korea)
• /
• v.34 no.1
• /
• pp.38-44
• /
• 2010

Core-shell particles of inorganic/organic pair were synthesized from $CaCO_3$ absorbed sodium dodecyl benzene sulfonate(SDBS) surfactant. Shell components were synthesized by sequential emulsion polymerization. Various monomers were used as shell components such as methyl methacrylate(MMA), ethyl acrylate(EA), butyl acrylate(BA), and styrene(St). Ammonium persulfate(APS) was used as an initiator and 2-ethylhexyl acylate(2-EHA) was used as a functional monomer, In the $CaCO_3$/organic core-shell particle polymerization, $CaCO_3$ absorbed surfactant SDBS of 0.5 wt% was prepared first and then core $CaCO_3$ was encapsulated by emulsion polymerization. 0.1 wt% of APS was added sequentially to minimize the formation of new monomer particle during shell polymerization. The structure of inorganic/organic core-shell particles were characterized by measuring the decomposition degree of $CaCO_3$ using HCl solution, thermogravimetric analyzer, scanning electron microscope, and transmission electron microscope.

• Fashion & Textile Research Journal
• /
• v.13 no.6
• /
• pp.972-982
• /
• 2011

The purpose of this study is to improve the method of color developing with alkali solution as a promotor of color developing for feasible use. Cotton fabric was dyed with persimmon extract ranged with 0~3% alkali component with 5 types of strong to mild alkali solution. Heat treatment for color developing was applied to fabric dyed with persimmon extract and alkali mixing solution. Tests were carried out to analyze the change of surface color, ${\Delta},Ea^*b^*$, and water repellent of the dyed cotton fabric. The alkali mixing sample showed higher ${\Delta},Ea^*b^*$ value than control one without alkali mixing on the base of dyed fabric due to high color developing by alkali in the initial step of dyeing process. As alkali concentration increased, deeper dark color appeared on the fabric. The fabric color was changed to more dark in the application of sodium hydroxide, sodium carbonate, potassium carbonate in the initial step of dyeing process but color was not changed by increased heating time. However, the fabric showed a slight dark color with sodium acetate and more color change than that of the fabric dyed with persimmon extract without alkali. Therefore, sodium acetate seemed to a suitable promotor for color developing in persimmon extract dyeing. Property of water repellent was showed after color developing by heating with low concentration of alkali treatment.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2003.10a
• /
• pp.21-24
• /
• 2003

In general, to enhance physical properties of PET-layered silicate nanocomposites $(P_{et}LSNs)$, it has been well known that the organic modifiers should introduce into gallery regions. However, the organic modifiers in$(P_{et}LSNs)$ may result in thermal decomposition by melt processing at high temperature, and it necessarily lead to deteriorate various physical properties of final products. Therefore, in this study, $(P_{et}LSNs)$ excluding and including organic modifiers were prepared by solution method $(S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom})$ and we (focused on the effects of the organic modifiers in $P_{et}$ LSNs with exfoliation structure on the crystallization behaviors, the optical transparency, the thermal stability and the mechanical property. The absence and existence of organic modifiers in $S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom}$ were investigated by EA and TGA, and nano-structure of silicate layers in $S-P_{et}LSNs$ was evaluated by using WXRD, SAXS and TEM. $S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom}$ were mixed with neat PET as masterbatches by melt method $(M-P_{et}LSNs_{eom} and M-P_{et}LSNs_{iom})$, and also neat PET was mixed with organically modified layered silicates (OLS) by conventional direct melt method $(D-P_{et}LSNs) at 270^{\circ}C$. As results, it was found that $M-P_{et}LSNs_{eom}, M-P_{et}LSNs_{iom}, and D-P_{et}LSN$ showed a exfoliated structure and exhibited faster crystallization rate, better thermal stability and mechanical property than those of neat PET due to the dispersed and detaminated silicate layers in PET matrix. Whereas, considering organic modifiers effect, $M-P_{et}LSNs_{eom} and D-P_{et}LSN$ exhibited slower crystallization rate, poorer optical, thermal and mechanical properties, in comparison to $M-P_{et}LSNs_{eom}> due to the thermal decomposition of organic modifier in $D-P_{et}LSNs$ during melt method.

• Korean Journal of Food Science and Technology
• /
• v.31 no.3
• /
• pp.638-643
• /
• 1999

In this study we prepared 5 types of nutritional beverage base samples containing various ratios of soy protein isolate (SPI) and sodium caseinate as protein source. The rheological properties of each sample were measured and the results were as followes; Samples changed their rheological properties with the ratio of SPI. Samples represented newtonian property with low ratio of SPI, pseudoplastic property with the increment of SPI, and bingham pseudoplastic property with higher increment of SPI (80% as protein source). In this result we conjectured that the more was the SPI, the more was the formation of progel during heat treatment, which could be the reason of the rheological changes. In the test of the relationship between temperature and apparent viscosity, apparent viscosity of samples decreased along with the increment of temperature. In observing the relationship between time and apparent viscosity, we found sample, containing high ratio of SPI (80%), represented thixotropic property clearly with the hysteresis loop.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.251.2-251.2
• /
• 2010

Plant biomass has been proposed to be an alternative source for petroleum-based chemical compounds. Especially, phenolic chemical compounds can be obtained from lignin by chemical depolymerization processes because lignin consists of complex aromatic polymer such as trans-p-coumaryl, coniferyl and sinapyl alcohols, etc. Phenolic chemical compounds from lignin were usually produced in super critical water. However, we applied Near-critical water (NCW) system because NCW is known as a good solvent for lignin depolymerization. Organic matter like lignin can be solved in NCW system and the system has a unique acid-base property without conventional non-eco-friendly chemicals such as sulfuric acid and sodium hydroxide. In this work, we tried to optimize the NCW depolymerization system by adjusting the processing variables such as reaction time, temperature and pressure. Moreover, the amount of additional phenol was optimized by changing the molar ratio between water and phenol. Phenol was used as capping agent to prevent re-polymerization of active fragment such as formaldehyde. Alkali-lignin was used as a starting material and characterized by a Solid State 13C-NMR, FT-IR and EA (Elemental Analysis). GC-MS analysis confirmed that o-cresol, p-cresol, anisole and 4-hydroxyphathalic acid were the main product and they were quantitatively analyzed by HPLC.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.8
• /
• pp.2546-2552
• /
• 2012

A novel biguanide-functionalized $Fe_3O_4/SiO_2$ magnetite nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperbase in chemical transformations. The structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (TEM), powder X-ray diffraction (XRD), vibrating sample magnetometry (VSM), elemental analyzer (EA), thermogravimetric analysis (TGA), $N_2$ adsorption-desorption (BET and BJH) and FT-IR. The biguanide-functionalized $Fe_3O_4/SiO_2$ nanoparticles showed a superpara-magnetic property with a saturation magnetization value of 46.7 emu/g, indicating great potential for application in magnetically separation technologies. In application point of view, the prepared catalyst was found to act as an efficient recoverable nanocatalyst in nitroaldol and domino Knoevenagel condensation/Michael addition/cyclization reactions in aqueous media under mild condition. Additionally, the catalyst was reused six times without significant degradation in catalytic activity and performance.

• Magazine of the Korea Concrete Institute
• /
• v.7 no.6
• /
• pp.224-232
• /
• 1995

Recently, in other.view of underwater concrete construction, special admixture agent of concrete has been developed for antiwashout of concrete under water with easy carrying out method in some foreign nations. They had successful cases in experiment and construction and it trend to use in many cases with many scales. However, in domestic, there was rare record in carrying out. In this paper, reference for successful results of experiment and construction about antiwashout underwater concrete, as variable add of special admixture agent and other agents. We have carried out property tests of fresh and hardened concrete, certified the properties and made the antiwashout underwater concrete have enough strength to endure with ea.sy construction. And we have decided the optimal mix proportion for antiwashout underwater concrete under standard state.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.6 s.183
• /
• pp.174-179
• /
• 2006

The curing characteristics of a photocurable resin are critical factors that often decide the ultimate resolution and structural sharpness of a final product fabricated by microstereolithography$(\mu-STL)$. In this study, we investigated the curing characteristics of the FA1260T photopolymer under a visible laser light of 42nm wavelength. Modification of the curing property of the FA1260T is attempted to reduce the cure depth $(D_c)$ by adding a radical quencher to the resin. Also, an organic solvent was used to reduce the resin viscosity for an improvement of the flatness of the liquid surface during layer-by-layer curing. As a result, the minimum $D_c$ has been reduced over a factor of 3 with no abrupt increase. Samples of three dimensional microstructures fabricated using the modified FA1260T are presented.

• Journal of Welding and Joining
• /
• v.25 no.3
• /
• pp.78-84
• /
• 2007

Laser Material Processing has been replaced the conventional machining systems - cutting, drilling, welding and surface modification and so on. Especially, LTH(Laser Transformation Hardening) process is one branch of the laser surface modification process. Conventionally, some techniques like a gas carburizing and nitriding as well as induction and torch heating have been used to harden the carbon steels. But these methods not only request post-machining resulted from a deformation but also have complex processing procedures. Besides, LTH process has some merits as : 1. It is easy to control the case depth because of output(laser power) adjustability. 2. It is able to harden the localized and complicated a.ea and minimize a deformation due to a unique property of a localized heat source. 3. An additional cooling medium is not required due to self quenching. 4. A prominent hardening results can be obtained. This study is related to the surface hardening of the rod-shaped carbon steel applied to the lathe based complex processing mechanism, a basic behavior of surface hardening, hardness distribution and structural characteristics in the hardened zone.