The present study was conducted to control Botrytis growth of cut roses during transport by applying hot water dipping. Water temperatures ranging from 40 – 70℃ and dipping time from 10 – 90 s were evaluated in vitro and in vivo. Hot water dipping at 50℃ inhibited mycelial growth depending on dipping time. Water temperature over 60℃ completely inhibited the pathogen growth even at exposure of 10 s while water below 40℃ did not have any effect. However, temperature over 60℃ rapidly damaged the tissue of rose petals. Dipping time below 40 s at 55℃ showed no significant difference on electrolyte leakage compared to control. In vivo, dipping flower heads in hot water reduced the severity of Botrytis rot. Dipping for 20 – 90 s at a temperature of 50℃ was more effective than at higher or lower temperatures. Heat treatment increased respiration rate and decreased slightly solution uptake, transpiration, fresh weight of flowers but dipping below 50℃ for 20 s did not affect vase life.

A severe outbreak of gray mold on kenaf (Hibiscus cannabinus L.) was observed on kenaf grown in the research field of Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Korea in 2014. Gray mold appeared on young plants as gray-brown velvety mold covering stems and leaves. Infections that girdled the stem caused wilting above the infected area and developed a canker. The casual fungus formed grayish brown colonies on potato dextrose agar. The conidia were one celled, mostly ellipsoid or ovoid in shape, colorless or pale brown in color, and 6–18 × 4–10 μm in size. The conidiophores were 15–32 μm in length. These measurements and taxonomic characteristics were most similar to those of Botrytis. DNA sequencing and phylogenetic analysis of the complete internal transcribed spacer rRNA gene region confirmed that the fungal isolates were indeed Borytis cinerea. Koch's postulates were supported by pathogenicity tests conducted on healthy plants. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea. To the best of our knowledge, this is the first report of a gray mold caused by B. cinerea on kenaf in Korea.

In this study, porous stainless steel (STS316L) sintered body was fabricated by powder metallurgy method and its properties such as porosity, compressive yield strength, hardness, and permeability were evaluated. 67.5Fe-17Cr-13Ni-2.5Mo (wt%) powder was produced by a water atomization. The atomized powder was classified into size with under 45 μm and over 180 μm, and then they were compacted with various pressures and sintered at 1210oC for 1 h in a vacuum atmosphere. The porosities of sintered bodies could be obtained in range of 20~53% by controlling the compaction pressure. Compressive yield strength and hardness were achieved up to 268 MPa and 94 Shore D, respectively. Air permeability was obtained up to 79 l/min·cm2. As a result, mechanical properties and air permeability of the optimized porous body having a porosity of 25~40% were very superior to that of Al alloy.

The optical film for light luminance improvement of back light unit that is used in light emitting diode/liquid crystal display and retro-reflective film is used as luminous sign consist of square and triangular pyramid structure pattern based on V-shape micro prism pattern. In this study, we analyzed machining characteristics of Cu-plated flat mold by shaping with diamond tool. First, cutting conditions were optimized as V-groove machining for the experiment of micro prism structure mold machining with prism pattern shape, cutting force and roughness. Second, the micro prism structure such as square and triangular pyramid pattern were machined by cross machining method with optimizing cutting conditions. Variation of Burr and chip shape were discussed by material properties and machining method.

Internet of Thing(IoT), which is recently talked about with the development of information and communication technology, provides big data to all nodes such as companies and homes, means of transportation etc. by connecting all things with all people through the integrated global network and connecting all actual aspects of economic and social life with Internet of Thing through sensor and software. Defining Internet of Thing, it plays the role of a connector of providing various information required for the decision-making of companies in the cloud computing environment for the Insight usage by collecting and storing Raw Data of the production site through the sensor network and extracting big data in which data is accumulated and Insight through this. In addition, as the industry showing the largest linkage with other root industries among root industries, the mold industry is the core technology for controlling the quality and performance of the final product and realizing the commercialization of new industry such as new growth power industry etc. Recently, awareness on the mold industry is changing from the structure of being labor-intensive, relying on the experience of production workers and repeating modification without the concept of cost to technology-intensive, digitization, high intellectualization due to technology combination according to IT convergence. This study, therefore, is to provide a golden opportunity to increase the direct and indirect expected effects in poor management activities of small businesses by actually implementing and managing the entire process of mold life cycle to information system from mold planning to mass production and preservation by building SME(small and medium-sized enterprises)-type mold life cycle management information system in the cloud computing environment and applying it to the production site.

균상느타리버섯에서 발생하는 곰팡이 병해 중에서 가장많은 문제를 발생하는 것은 Trichoderma disease 또는green mould 등으로 불리우는 푸른곰팡이병이다.이 병은 Trichoderma, Penicillium, Aspergillus 등의 속(genus)에 포함되는 종들에 의해 발병되는 병을 총칭하는것으로 발생빈도와 피해가 가장 큰 것은 Trichoderma 속의 병원균에 의해 발생하였다. 느타리버섯 균상에 분리된 병원균은 T. longibrachiatum,T. koningii, Trichoderma virens, T atroviride, T. hazianum,T. pseudokoningii 6종이었으며, 발생빈도가 높은 것은 T.virens, T. hazianum, T. longibrachiatum 3종이었고, 각각의 균은 배양적 특성 및 병원성도 각기 다른 특성을 보이고 있었다.T. longibrachiatum 균사생장이 매우 빠르고, 포자형성이 빠르며, 특히 후막포자형성이 잘되는 특성을 있으며,후기에는 진한 녹색으로 변색된다. Trichoderma koningii는 균사생장은 빠르고, 공중균사가 많은 편이며, 포자는공중균사에 밀집되어 형성된다. 특히 Trichoderma virens같은 경우에는 포자형성에 의한 색깔변화가 느리며, 감염후기에 발견되어 그 피해가 심한 편이었다. Trichodermaatroviride. 균사생장은 보통이며, 포자형성은 공중균사에드믈게 형성되며, 후기에는 진녹색을 띤다. 이균의 특징은coconut 냄새와 유사한 향기가 나는 것이다. T. hazianum은 초기에는 균사가 백색으로 매우 빠르고, 공중균사에포자가 형성하며, 후기에는 진한 녹색으로 변색된다. 공중균사에 형성된 포자는 육안적으로 pustules or tufts의 형태를 나타내었다. Trichoderma pseudokoningii 균사생장은 빠르며, 포자형성은 접종부위를 중심으로 형성되며, 후기에는 환무니를 형성하며, 특히 배지 색이 변색되고 후막포자 잘 형성되는 특징이 있었다.

기계가공으로 인한 사고는 작업자에게 치명적인 경우가 많다. 이러한 사고는 완벽한 가공지그을 통해 대부분 예방이 가능하지만 제품설계초기 후가공과 양산 공정은 고려되지 않고 설계되어 기계가공 시 재해로 연결되는 경우가 빈번히 발생하고 있다. 사형 주조법은 수작업으로 손쉽게 제품을 생산하는 장점을 가지는 반면 치수오차가 다른 양산공정 보다 크다는 단점을 가진다. 이런 사형 주조품을 기계 가공할 때 제품의 치수편차로 인해 불안전한 고정및 과다한 절삭, 제품이탈, 공구파손, 장비와 공구의 빠른 수명감소 등의 다양한 문제가 발생 하지만 사형주조의 특성상 개선하기 어려운 문제로 인식되고 있다. 본 연구에서는 원형의 용기형태의 제품을 사형주조 후 기계가공 하는 것을 금형으로 대체하기 위한 셸몰드법을 제시하고 셸몰드로 만든 셸주형으로 주조함으로서 표면조도 평균 Ra9.94㎛의 기계가공에 준하는 표면을 구현하였다. 외형의 정밀한 제품을 대량 생산하여 가공공정의 간소화 및 평균 두께 편차를 줄임으로서 제품파손 및 제작 시 발생할 수 있는 안전사고예방에 긍정적인 영향을 주었다. 기계가공전 제품의 치수정밀도를 높여 안전성, 생산성향상, 가공 공정단축, 환경개선 등을 이 가능함을 확인하였다.

온실 및 식물공장 작물재배에 있어서 LED 광원과 작물생육에 관한 연구들은 활발히 진행 되고 있으나, LED광원과 식물에 병을 일으키는 식물병원균에 대한 연구들은 미흡하다. LED 광원은 이미 시설재배 혹은 식물공장에 설치되어 있으므로 LED광원으로 식물에 발생하는 병원균을 제어할 수 있다면 방제에 필요한 인적, 시간적 비용과 살균제 등과 같이 인체에 유해한 성분들의 사용을 감소시킬 수 있을 것으로 판단하여 LED광원에 대한 Botrytis cinerea의 균사생장을 조사하였다. 식물공장에서는 주로 엽채류를 재배하며 엽채류에는 여러 가지 곰팡이균들에 의한 질병 발병 가능성이 충분히 내재되어 있다. 병원균의 포자는 항상 작물재배지에 존재하고 있기 때문에 LED 광원이 식물병원균의 균사 생장을 억제 할 수 있다면, 식물공장내에서 작물재배에 효과적으로 이용할 수 있을 것으로 판단된다. 식물공장의 광원중 가장 많이 보편화되어 있는 LED 광원을 이용하여 B. cinerea의 균사 생장을 조사한 결과 Blue 광원에서 균사 생장이 억제되는 것을 관찰할 수 있었다. 이러한 결과는 식물공장내 LED의 비율과 광량의 적절하게 조절함으로써 식물병원균의 증식을 억제 할 수 있을 것으로 판단된다.

In this study, mold core of can type lens for optical communication has been fabricated and heat transfer analysis has been conducted. Through this study, results were obtained as follows. Surface roughness of upper and lower cores by ultra precision grinding were Ra 0.002074(um) and 0.004316(um), respectively. Design P-V and Bestfit P-V as shape accuracy of upper core were 0.0858(um) and 0.0843(um), respectively, and those of lower core were 0.0957(um) and 0.0546(um), respectively. The temperatures of upper and lower surfaces of lens during machining obtained by heat transfer analysis were 576.05℃ and 576.4℃, respectively. In case of inner sleeve, it was estimated that the temperature of the side surface were 575.95℃ by heat transferred from lower core. The maximum and minimum temperatures of lower surface of lens were 576.4℃ and 575.96℃, respectively, according to the positions of holes for air circulation from out side.

To fabricate a precise micro metal mold, the electrochemical etching process has been researched. We investigated the electrochemical etching process numerically and experimentally to determine the etching tendency of the process, focusing on the current density, which is a major parameter of the process. The finite element method, a kind of numerical analysis, was used to determine the current density distribution on the workpiece. Stainless steel(SS304) substrate with various sized square and circular array patterns as an anode and copper(Cu) plate as a cathode were used for the electrochemical experiments. A mixture of H2SO4, H3PO4, and DIW was used as an electrolyte. In this paper, comparison of the results from the experiment and the numerical simulation is presented, including the current density distribution and line profile from the simulation, and the etching profile and surface morphology from the experiment. Etching profile and surface morphology were characterized using a 3D-profiler and FE-SEM measurement. From a comparison of the data, it was confirmed that the current density distribution and the line profile of the simulation were similar to the surface morphology and the etching profile of the experiment, respectively. The current density is more concentrated at the vertex of the square pattern and circumference of the circular pattern. And, the depth of the etched area is proportional to the current density.

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relation between injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects were dif

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relation between injection systems, casting condition, gating system, and cooling system. Also, the extent or the location of product defects will be differentiated according to the various relations of the above conditions. High-qualified products can be manufactured as those defects are controled by the proper modifications or the changes of die casting mold with the conditions. In this research, the proper manufacturing method intensively be derived for reducing the defect of the internal porosities issues of power steering which is very complicated to achieve the mold design, and for minimizing and for guaranteeing the product quality through the analysis of the problem of casting parts and the deduction of alternative plans.

This paper describes the manufacturing process of tilting pad gas bearing with a diameter of 5 mm and a length of 0.5-1 mm for power MEMS (Micro Electomechanical Systems) applications. The bearing compacts with nanopowder feedstock were prepared by Ni-metal mold with 2-mold system using LIGA process. The effect of the manufacturing conditions on sintering properties of nanopowder gas bearing was investigated. In this work, Fe-45 wt%Ni nanopowder with an average diameter of 30-50 nm size was used as starting material. After mixing the nanopowder and the wax-based binders, the amount of powder was controlled to obtain the certain mixing ratio. The nanopowder bearing compacts were sintered with 1-2 hr holding time under hydrogen atmospheres and under temperatures of to . Finally, the critical batch of mixed powder system was found to be 70% particle fraction in total volume. The maximum density of the sintered bearing specimen was about 94% of theoretical density.

금속 주조시 사용되는 탄소이형제를 카본블랙과 점증제 겸 알데하이드 화합물의 경화제로 사용될 수 있는 수용성 고분자인 잔탄검(X-gum), 카르복시메틸셀룰로오스(CMC)을 혼합하여 제조하였다. 이 때 카본블랙의 안정한 분산을 위하여 0.25 wt%의 X-gum 또는 1.0 wt%의 CMC가 적당하였다. 1.0 wt% 보다 낮은 농도의 CMC를 사용했을 경우 카본블랙이 매우 쉽게 층분리되었다. 유리판에 대한 부착력은 경화제와, 구르탈알데하이드 및 사슬연장제인 올리고당의 양에 비례하였으며. X-gum으로 제조된 탄소 이형제는 CMC를 이용해 제조된 것보다 유리에 대한 부착력이 우수하였다. 결과적으로 본 실험의 최적 조건에서 제조된 탄소이형제는 친환경적으로 주조시에 적용할 수 있을 것으로 판단된다.

It is not easy to predict the shrinkage rate of a plastic injection mold in its design process. The shrinkage rate should be considered as one of the important performances to produce the reliable products. The shrinkage rate can be determined by using the CAE tools in the design produces. However, since the analysis can take minutes to hours, the high computational costs of performing the analysis limit their use in design optimization. Therefore this study was carried out to presume for mutual relation of analysis condition to get the optimum average shrinkage by regression analysis. The results shown that coefficient of determination of regression equation has a fine reliability over 87% and regression equation of average shrinkage is made by regression analysis

Currently, there are two main issues regarding the development of core technologies in the automotive industry: the development of environmentally friendly vehicles and securing a high level of safety in the event of an accident. As part of the efforts to address these issues, research into alternative materials and new car body manufacturing and assembly technologies is necessary, and this has been carried out mainly by the automotive industries. Large press molds for producing car body parts are made of cast iron. With the increase of automobile production and various changes of design, the press forming process of car body parts has become more difficult. In the case of large press molds, high hardness and abrasive resistance are needed. To overcome these problems, we attempted to develop a combined heat treatment process consisting of local laser heat treatment followed by plasma nitriding, and evaluated the characteristics of the proposed heat treatment method. From the results of the experiments, it has been shown that the maximum surface hardness is 864 Hv by the laser heat treatment, 953 Hv by the plasma nitriding, and 1,094 Hv by the combined heat treatment. It is anticipated that the suggested combined heat treatment can be used to evaluate the durability of press mold.

Carbon material shows relatively high strength at high temperature in vacuum atmosphere and can be easily removed as CO or gas in oxidation atmosphere. Using these characteristics, we have investigated the applicability of carbon mold for precision casting of high melting point metal such as nickel. Disc shape carbon mold with cylindrical pores was prepared and Ni-base super alloy (CM247LC) was used as casting material. The effects of electroless Nickel plating on wettability and cast parameters such as temperature and pressure on castability were investigated. Furthermore, the proper condition for removal of carbon mold by evaporation in oxidation atmosphere was also examined. The SEM observation of the interface between carbon mold and casting materials (CM247LC), which was infiltrated at temperature up to , revealed that there was no particular product at the interface. Carbon mold was effectively eliminated by exposure in oxygen rich atmosphere at for 3 hours and oxidation of casting materials was restrained during raising and lowering the temperature by using inert gas. It means that the carbon can be applicable to precision casting as mold material.

Mold infestation problems in building are a complex phenomenon due to various causes such as environmental conditions including temperature and relative humidity, substrates (building materials), exposure time, and so on. Earlier studies showed the interrelationship among humidity, temperature conditions and mold growth. However, surface structure also can be a key factor to mold germination. This study conducted experiments on the mold germination and growth on wallpapers with different surface structures. Four wallpapers and two fungal species (Aspergillus versicolor, Penicillium chrysogenum) were selected for experiment and observed fungal germination and growth on the different surface structures of wallpapers using scanning electron microscope. The resulfts showed that the shape of the micro structure of wallpaper surface affected to the growth of fungi.

Recently, the engineering designer of injection mold has become more and more dependent on the CAE. In the design factors of injection mold, the shrinkage rate should be considered as one of the important performances to produce the reliable products. Therefore, the shrinkage rate can be mostly calculated by the MoldFlow and CATIA in the design process. However, it is not easy to predict the shrinkage rate of a plastic injection mold in its design process because the analysis can take minutes to hours, the high computational costs of performing the analysis limit their use in design optimization. In this study, the surrogate models based on the Taguchi Design in order to optimize the shrinkage rate of bevel gear injection mold is used instead of the original models, facilitating design optimal design.