• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.5
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• pp.769-774
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• 2010

It happened fractures on special bolt which supported main landing gear actuator up-lock rod of aircraft. Cracks were initiated mainly from the center hole and the external thread of the special bolt. To find out failure root causes, metallographic, fractographic analyses as well as test work were carried out. From the fractographic study by SEM work, fracture occurred by a brittle intergranular type failure. The fracture could be occurred primarily by solid-metal-induced embrittlement due to cadmium embrittler penetrated into the flaw existed after machining work for center hole and thread on the bolt during baking treatment processing to eliminate hydrogen. For its successful application, cadmium EP bolts require proper and adequate baking treatment after electroplating, and make no more drilled center hole on the bolt to prevent same failure.

• Transactions on Electrical and Electronic Materials
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• v.7 no.2
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• pp.81-86
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• 2006

In this paper, the response surface modeling of the control of the pretilt angle in the nematic liquid crystal on the homogeneous polyimide surface with different surface treatment is investigated. The pretilt angle is one of the main factors to determine the alignment of the liquid crystal display. The pretilt angle is measured to analyze the variation of the characteristics on the various process conditions. The rubbing strength and the hard baking temperature are considered as input factors. After the design of experiments is performed, the process model is then explored using the response surface methodology. The analysis of variance is used to analyze the statistical significance and the effect plots are also investigated to examine the relationship between the process parameters and the response.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.178-185
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• 2016

The influence of three cooking methods (stewing, microwaving and Aluminium (Al) foil-baking) was evaluated on the content of intramuscular lipid and the composition of intramuscular fatty acids of Hyla rabbit. The percentage of intramuscular lipid in cooked-longissimus dorsi (LD) (dry weight %) were in the order mentioned below: microwaving > foil-baking > stewing. All treated samples showed decrease in the proportion of polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA), whilst increase in the proportion of saturated (SFA) and n-6/n-3 value during processing. All of the cooked samples had the n-6/n-3 ratio within the recommended range (5-10). By the analysis of partial least squares regression (PLSR), the microwaving treatment was better to keep the stability of unsaturated fatty acids (UFA), whilst the long-time Al foil-baking did the most serious damage to UFA, especially the PUFA. In addition, the heating method showed greater influence on the samples than the processing time. The shorter processing time was better to retain the intramuscular PUFA of Hyla rabbit, especially the LC-PUFAs (C20-22). Considering all the factors, microwaving showed the superiority in reserving the composition of intramuscular fatty acids of Hyla rabbit.

• The Korean Journal of Food And Nutrition
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• v.33 no.6
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• pp.681-691
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• 2020

This study was conducted to evaluate the characteristics of bread and the rheology of flour dough containing chlorella powder(0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%). In the farinograph test, the addition of chlorella powder changed water absorption, development time and mixing tolerance index for making bread. As the amount of chlorella powder increased, the water absorption increased, mixing tolerance index and the development time decreased. In the extensograph test, the degree of extension and resistance was decreased with increasing of chlorella powder content. In the amylograph test, the maximum viscosity was slightly decreased with increasing of chlorella powder contents. The colors of L value in bread crumb was significantly decreased as the chlorella powder addition. After fermentation treatment, The dough with 2.5% chlorella powder showed the lowest dough raising power compared to the other doughs. The addition of the chlorella powder had significant effect on bread texture. The bread consisting of 0.5% chlorella powder showed the highest volume of loaf and specific volume. Therefore, high quality of bread can be achieved by adding chlorella powder.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.151-156
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• 2015

In order to improve the properties of high-temperature superconducting wire for superconducting cable system, we optimized the electro-polishing (EP), ion-beam assisted deposition (IBAD), superconducting (SC) layer, and baking (heat) treatment. The buffer layer was deposited on electro-polished substrate with RMS roughness ($R_{RMS}$) less than 5 nm. The IBAD process was carried out at $V_{beam}$: 1100 V and $V_{accel}$: 850 V that resulted in highly crystalline film of $LaMnO_3$. Chemical composition of SC layer is key to higher critical current, and we found that composition can be determined by surface color of SC layer. We adopt a proprietary contorl system based on RGB analysis of the surface and achieved critical current of 150 A/4 mm-width. The proposed baking treatment resulted in decreasing of about 10% of fraction defects.

• Journal of Welding and Joining
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• v.27 no.6
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• pp.62-67
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• 2009

Friction stir welding (FSW) was carried out for Al-Mg-Si series aluminum alloys which are being used for automotive body structure. Consequently, Post weld heat treatment (PWHT) was applied to the friction stir welds to evaluate the effect of the paint baking process which is one of the automotive fabrication process on friction stir welded zone (FSWZ) in 443K for 1.2Ks. Grain structure and its crystal orientation distribution was measured about both the as welded specimens and the post weld heat treated specimens. An optical microscope (OM) and an field emission scanning electron microscope (FE-SEM) was used for observing the grain structure and measuring its crystal orientation distribution, respectively. Changes on the grain structure and its crystal orientation distribution were not detected. From the present results, it was confirmed that the paint baking process after FSW do not affect on the grain structure and its crystal orientation distribution of FSWZ. The comprehensive investigations will be performed for various automotive aluminum alloys manufactured by different processes, in the future.

• The Journal of Korean Academy of Prosthodontics
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• v.18 no.1
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• pp.49-57
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• 1980

The adhesive mechanisms on the metal-ceramic restorations have been reported to be mechanical interlocking, chemical bonding, compressive force, and Van der Waal's force, etc. Of these, the mechanical interlocking and chemical bonding forces are thought to affect the adhesive force between Ni-Cr alloy and porcelain. This study investigates the adhesion of Ni-Cr alloy to porcelain according to surface treatment. For this purpose, the following experiments were made; The compositions of Ni-Cr alloy as cast by emission spectrograph, and the oxides produced on Ni-Cr alloy during degassing at $1850^{\circ}F$ for 30 minutes in air and in vacuum were analyzed by X-ray diffractograph. The metal phases of Ni-Cr alloy were observed according to porcelain-baking cyclic heat treatment by photo microscope and the distribution and the shift of elements of Ni-Cr alloy and porcelain and the failure phases between Ni-Cr alloy and porcelain by scanning electron microscope. The adhesive force between Ni-Cr alloy and porcelain was measured according to surface treatment with oxidization and roughening by Instron Universal Testing Machine. Results were as follows; 1. The metal phases of Ni-Cr alloy as cast and degassing state showed the enlarged and fused core, but when subjected to porcelain-baking cyclic heat treatment, showed a dendrite growing. 2. The kinds of metal oxides produced on Ni-Cr alloy during degassing were found to be NiO and $Cr_2O_3$. 3. The distribution of elements at the interface of Ni-Cr alloy and porcelain in degassing state showed demarcation line, but in roughening state, showed mechanical interlocking phase. 4. The shift of elements at the interface occurred in both states, but the shift amount was found to be larger in roughening than in degassing. 5. The adhesive force between Ni-Cr alloy and porcelain was found to be $3.45{\pm}0.93kg/mm^2$, in degassing and $3.82{\pm}0.99kg/mm^2$, in roughening. 6. The failure phase between Ni-Cr alloy and porcelain showed the mixed type failure.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.512-523
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• 1999

A purpose of this study was to figure out the best cooking conditions of salted-dried fish by a sensory evaluation on cooked salted-dried flathead. Cooking of the salted-dried fish is traditional and popular in Korea, and salted-dried flathead is a favorite with southern Korea. The raw material for the examination were a raw flathead and 3 degrees salted(2%, 4%, 6%)-dried flathead which added 3 kinds cooking treatment (steaming, boiling, baking) within three different times(5, 10 and 15 min.) respectively. The category scaled descriptive test and response surface methodology were applied for the evaluation, and the results of the evaluation were analyzed by SAS program. The result of the study were as follows : 1. For the steaming cooking, scale at 6% salt concentration and 5 minutes cooking time were the best conditions of the salted-dried flathead cooking. 2. For the boiling, 6% salt concentration and 10 minutes cooking time were the best conditions. 3. For the baking, 6% salt concentration and 10 minutes cooking time were the best conditions. 4. The baking group got higher estimations on the items of browning, cooked condition and meaty aroma than steaming and boiling group on Duncan's multiple range test. According to the result of the Duncan's test, baking is better cooking way for the salted-dried flathead.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.157-164
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• 2018

The purpose of this study was to develop a kelp (Laminaria japonica) product with optimal sensory and nutritional properties for eating as a snack by investigating its physicochemical properties and conducting sensory evaluation. A preliminary study using tripolypolyphosphate solution found that it was good for removing the fishy smell and for making it soft. We soaked the kelp in 0.3-0.4% sodium tripolyphosphate buffer and tested with or without baking. In searching for the optimal polyphosphate dilution concentration, soaking in 0.3-0.4% sodium tripolyphosphate resulted in the best texture and flavor. As kelp separates into thick or thin samples, thick kelp was best when soaked in 0.4% sodium tripolyphosphate buffer and thin soaked in 0.3%. The kelp snack made from the thick one (over 221 mm thickness) was better than the thin one. Baking improved the moisture, texture and feel of the kelp snack. Tripolyphosphate treatment affected protein contents and texture softening. The differences by baking and tripolyphosphate treatment were shown with electromicroscopic image. Kelp snacks with added sweet and hot taste were preferred to sour taste. In conclusion, in making kelp snacks, it is advisable to use a thick kelp, 0.3-0.4% sodium tripolyphosphate, and baking treatment for better texture and feel. This kelp snack has low fishy smell, better taste and soft feel. Further research is needed to support sea food's importance, and usefulness of the kelp snack to help prevent goiter in inland province citizens.

• 한국기계연구소 소보
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• s.20
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• pp.105-114
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• 1990

The relationship between the properties of two kinds of calcined cokes and graphitized forming bodies were examined. The microstructures of the forming bodies are already determined to some degree at the stage of baking. Calcined cokes as well as baked forming bodies using the same coke as filler were heat treated at various temperatures and their structural and properties changes with heat treated temperature were studied. The transition in properties changes with heat treatment in forming bodies were observed around $2000^{\circ}C$. The characteristics of the finial graphite bodies are strongly dependent on the properties of the raw material cokes.