Case Study Development of Welding Machine for Sterling Silver Jewelry Parts With 500-amp electrical arc system for welding closing porous jewelry after casting. The problem can be solved by welding closing porous or by the jewelry. It is an alternative to repairing the work piece. The efficiency of electrical arc welding equipment can be repaired to a certain extent. Based on the results of the experiments the welding and repairing porous porcelain parts were rated at 500 amperes by random sampling of 4 time slots 5 seconds 10 seconds 15 seconds and 20 seconds. Examine the most appropriate porous or porous workpiece for 20 seconds with 18 complete workpieces capable of sealing or milling. A good percentage of 90 percent of the performance of an electrical arc welding machine for welding sealing or cutting.

This research is a study of the optimum heat temperature for baking sintered castings for burnout removal of EC 500 type ash wax from cast mortar. Improving jewelry casting process to reduce waste from silver jewelry production process. By studying the temperature of the mortar. To burn remove wax from the mortar and clean the gaps. Then try to bring silver water instead of metal casting. The results of a baked casing study using the EC500 housing prototype from the study showed that the EC500 wax material is melted from all solids to ash wax by heating at 850 ° C to burn. Remove ash wax which makes the cavity clean. When the casting was casted with 925 sterling silver the most complete workpiece after the improvement of the waste jewelry casting process was found to be 1 piece 1 percent 99 pieces or 99 percent.

This Research is a Development of 8k White Gold low Alloy Metal Components for Jewelry Pieces. By Study and Analyze the Influence of Silver Alloy Gold Alloy Bronze Alloy Zinc Alloy and Tin Alloy. Which Affect Microstructure and Mechanical Properties. (The Different of Color Scales) And Resistance Behavior of Lowered 8k White Gold Alloy in Varies Ratio. The Results Showed that Tests and Analysis to Find the Quantities of Elements has found out that Chemical Components of 8k White Gold Low Alloy Metal had a Little Different Quantities when Compared Between Before and After Centrifugal Casting Process. The Tests and Analysis Results of Mechanical Properties of Test Pieces Showed that the Hardness and Tensile Strength of 8k White Gold Low Alloy Metal with Mixture of 33.33%Au+50.67%Ag+10%Cu+5%Zn+1%Sn had Minimum Ultimate Tensile Strength Equal 0.54 kN/mm2 Minimum Elongation Percentage of 55% and Maximum Hardness of 137.0 HV. The Test Results also Show that the Mechanical Properties of the Material are Brittle Material. When Perform a Forming Process the Pieces will be Easily Broken which was Meant that the Forming Process would be Difficult. But The Color Level of the Test Pieces at this Composite Ratio had the Best Metal Color Level. The Brightness L * = 74.87 was a * = -0.89 b * = 13.74 and the Value of ΔE with the Lowest Color Difference Level of 1.35. Compared to other Varies Ratio. It Showed that 8k White Gold Low Alloy Metal Test Pieces were Very Green and Came out Slightly Yellow Compared to the Blue Line that Approached the Standard Line. These Properties were the Physical Properties Required in 8k White Gold Low Alloy Metal Jewelry Pieces Production. Also there were the Results of 8k White Gold Low Alloy Metal in Two Formulas 8k 33.33%Au+50.67%Ag +8%Cu+7%Zn+1%Sn 33.33%Au+50.67%Ag+8%Cu+8%Zn+0%Sn. These Formulas had Tensile Strength in the Range of 1.10 0.60 kN /mm2 Elongation Percentage in the Range of 70 61% and Hardness of 115.6 123.3HV Respectively. The Results of the Mechanical Properties Test of the Test Pieces Showed that 8k White Gold Low Alloy Metal 33.33% Au+50.67%Ag+8%Cu+7%Zn+1%Sn has Similar Tensile Strength but Maximum Elongation Percentage of 70% and Minimum Hardness of 115.6HV. Which was Suitable for Forming Because of good Ductility and Stretchness Properties (Ductile Material). Forming would be Easy. These were Good Mechanical Properties for Forming Precious Metals.

The purpose of the study on Knowledge and Understanding of Personal Income Tax Planning is to study the knowledge and understanding on personal income tax problems and obstacles of individual taxpayers regarding internet tax filing. The study compared the level of knowledge understanding and planning of personal income tax of the sample with different demographic factors. The questionnaire was used as a tool to collect data. A total of 410 samples were used for one-way analysis of variance (One Way ANOVA) and compared by Least-Significant Different (LSD). The research found that the overall understanding of personal income tax planning was moderate. The most knowledgeable issues were net income taxable income expenses and tax reduction which were in high level. Secondly the issue of “the personal income tax rate is a progressive tax rate” was in a very high level. The lowest level was “each type of assessment has different deduction rates”. “Type 1 income has the least expense deductible rate” was in moderate level. In conclusion different gender occupation and education levels have statistically significant knowledge and understanding on tax planning.

The purpose of this research was to investigate the optimum heat temperature for the EC500 wax cured basecoat extrusion from all castings without waxing in the mortar. To reduce waste when the casting mortar through the casting process Silver Sterling 925 silver jewelry company Muang District Chiang Mai where the waste is caused by waxing outflow. The imperfections and leave waxing inside. Experiment with high temperature heat in mortar. And analyze the quality of work surface after casting with microscope. To find defects such as droplets and porosities caused by a range of temperatures. Temperature of baking mortar There is a difference from the conventional waxing mortar temperature. That is outflow of EC500 type wax. In the mortar to live. High heat The results of the 100 sample EC500 wax samples were tested at a temperature of 25 ° C. The mortar temperature was 700 ° C. 60 percent of waste was found the mortar was laid at 750 ° C 54 percent of waste was found. The mortar temperature was 800 ° C 32 percent waste was found the mortar temperature was 850° C Detecting 1 percent waste. The results of the study show that heat temperatures of up to 850 ° C can solve the problem of casting sterling silver alloys from the EC500 wax model. Finds the least waste.