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A Study on the Complex Color Analysis by Industry for Signboard Improvement Project - Focused on the Jongno-gil, Dongsang-dong, Gimhae-si - (간판개선사업을 위한 업종별 복합 색채 분석 연구 - 김해시 동상동 종로길을 중심으로 -)

  • Park, Han Na;Son, Jeong Eun;Choi, In Kyu;Paik, Jin Kyung
    • Korea Science and Art Forum
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    • v.37 no.4
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    • pp.149-159
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    • 2019
  • This research was started to identify the color status of signboards at the target site and suggest the direction of improvement for the signboard project in Dongsang-dong, Jongno-gil, a central area of the old city center of Gimhae. The area under study forms a depressed street atmosphere with old facilities, and is a typical type of old city center sign that needs to be rebuilt. The purpose of this study is to investigate prior research related to signage and similar signboard improvement cases, and then to identify the current status of colors by sorting out the casting, auxiliary and highlighted colors through the survey of the color of the signboard in the target area, and to propose a desirable direction for the future sign business based on the basis of these findings. This paper divided the target sections by industry and conducted a color analysis of signboards. The results and contents of the research are as follows. First, cast-colored signboards in general businesses showed a variety of primary color distributions with high L* values, on average, with high intensity and high chromaticity. Second, the auxiliary colors were mostly white or black in color-free, making a contrast between the casting colors. Third, the highlight was that a* value showed a high distribution in positive water plus and was mainly distributed in obsolescence, such as red or yellow, and color was used to reflect the characteristics of each store. However, the stores in the entire section lack unity because they were using colors that were higher in color than middle colors, which was causing the street's aesthetic look to be undermined. Based on the results of these studies, it is thought that the future color scheme for Gimhae's signature improvement project will limit the number of colors to a certain extent and give a sense of security and visual comfort to the use of colorlessness and obscurity around the representative colors of Gimhae.

A Study on the Material and Production Method of Bronze Casting Earthen Mold - Focusing on Earthen Mold Excavated in Dongcheon-dong, Gyungju - (청동주조 토제범(土製范)의 재질과 제작기법 연구 - 경주 동천동 출토 토제범을 중심으로 -)

  • Son, Da-nim;Yang, Hee-jae
    • Korean Journal of Heritage: History & Science
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    • v.46 no.4
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    • pp.108-125
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    • 2013
  • This study examined the actual reconstruction drawing, composite mineral, particle size and property test, fine organic matters, color differences and main ingredients of the earthen mold excavated in Dongcheon-dong, Gyungju. The cross-section of the inner mold and outer mold divides into inside (1st layer) and outside (2nd layer), with organic matters mixed outside. The cross-section has been altered due to heat and form removal agent. X-ray analysis revealed that the layer was made of minerals with high transmissivity and only quartz particles were observed through a polarizing microscope. The inside of cross-section in SEM observation identified enlarged air gap, with crack developed in the center, but no changes observed on the outside. The particle size of the composites is almost the same for the inner mold and outer mold and is silt clay loam. The ratio between silt clay and silt clay loam was about 2.7:1 and 2.9:1 respectively. In the property test, the density and absorption rate of inner mold and outer mold were similar, but porosity was different, with inner mold of 27.36% and outer mold of 31.09%. The color difference of cross-section seems to have been caused by the spread of soot on the 1st layer surface for removal of form or by the covering of ink to protect the 1st layer. Composite mineral analysis revealed the same composition for the inner mold and outer mold, except for the magnetite that was detected in the inner mold alone. As for the main ingredient analysis, the average content of $SiO_2$ was 71.64% and that of $Al_2O_3$ was 14.59%. As for the sub-ingredients, $Fe_2O_3$ was 4.51%, $K_2O$ 3.06%, $Na_2O$, MgO, CaO, $TiO_2$, $P_2O_5$ and MnO was less than 2%.

Effects of primers on the microtensile bond strength of resin cements to cobalt-chromium alloy (레진 시멘트와 코발트 크롬 합금의 미세인장결합강도에 다양한 프라이머들이 미치는 영향)

  • Jung, Hong-Taek;Campana, Shiela A.;Park, Jin-Hong;Shin, Joo-Hee;Lee, Jeong-Yol
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.2
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    • pp.95-101
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    • 2019
  • Purpose: The aim of this study is to evaluate the effects of various primers on the microtensile bond strength (${\mu}TBS$) of resin cements to cobalt-chromium (Co-Cr) dental casting alloy. Materials and methods: Four adhesive primers (Universal primer, Metal primer II, Alloy primer, and Metal/Zirconia primer) and two resin cements (Panavia F2.0, G-CEM LinkAce) were tested. One hundred fifty Co-Cr beams were prepared from Co-Cr ingots via casting ($6mm\;ength{\times}1mm\;width{\times}1mm\;thick$). The metal beams were randomly divided into ten groups according to the adhesive primers and resin cements used; the no-primer groups served as the control (n = 15). After sandblasting with aluminum oxide ($125{\mu}m$ grain), the metal and resin cements were bonded together using a silicone mold. Prior to testing, all metal-resin beams were examined under stereomicroscope, and subjected to the ${\mu}TBS$ test. The mean value of each group was analyzed via one-way ANOVA with Tukey's test as post hoc (${\alpha}=.05$) using SPSS software. Results: The mean ${\mu}TBS$ of all groups was ranged from 20 to 28 MPa. There is no statistically significant difference between groups (P > .05). Mixed failure, which is the combination of adhesive and cohesive failures, is the most prevalent failure mode in both the Panavia F2.0 and G-Cem LinkAce groups. Conclusion: The ${\mu}TBS$ of all tested groups are relatively high; however, the primers used in this study result in no favorable effect in the ${\mu}TBS$ of Panavia F2.0 and G-Cem LinkAce resin cement to Co-Cr alloy.

Survey of Current Status of Casting Industry in Korea (국내 주조산업 현황조사)

  • Cho, Minsu;Lee, Jisuk;Lee, Sanghwan;Lee, Sangmok
    • Journal of Korea Foundry Society
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    • v.41 no.2
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    • pp.144-152
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    • 2021
  • Based on the analysis of the current state of the world's foundry industry, we looked at the international competitiveness of Korea's foundry industry for the past 20 years. Korea's total foundry production is 2.52 million tons, and the production per company (so-called productivity) is 2,831 tons, which is the eighth largest in the world and down one position for the case of total foundry production, while productivity remains its position compared to three years ago. Korea is the only one of the top 10 foundry to see a decline in production. Similar to the global situation, Korean products consist of 38% of grey csat iron, 31% of ductile cast iron, 15% of aluminum, and 9% of cast steel. In order to obtain statistics on Korea's foundry industry, the survey conducted a service project for approximately nine months from April 2020. Various statistical surveys and sample in-depth surveys by the Korean standard industry class were evaluated for various contents of the domestic casting industry. We also looked at the number of companies, the distribution by region, the number of workers and the percentage of foreigners, and the distribution of each job, as well as the R&D investment status according to the size of the enterprise. Together, sales, exports, sales and various profit ratios were analyzed to measure the earning power of foundry industry. In addition, the classification by grouping the foundry industry according to the process utilized by focusing on each company, and to determine the sales, exports, and yield status for each process was also investigated on the basis. Based on these data, the domestic foundry industry has presented a variety of offers for the following issues for sustainable growth; global ranking, marginal corporate restructuring, training of domestic technical people, differentiated support policies by company size and process.

Analysis of the operation status and opinion on the improvement of fishing vessel structure in coastal improved stow net fishery by the questionnaire survey (설문조사를 통한 연안개량안강망어업의 조업 실태 및 어선 구조 개선에 관한 의견 분석)

  • CHANG, Ho-Young;KIM, Min-Son;HWANG, Bo-Kyu;OH, Jong Chul
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.57 no.4
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    • pp.316-333
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    • 2021
  • In order to understand basic data for improving the fishing system and fishing vessel structure in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 to analyze opinions on the improvement of operation status and fishing vessel structure. The questionnaire survey consisted of ten questions on the operation status of coastal improved stow net fishery and six questions on the improvement of fishing vessel structure, and the results of each question were analyzed by the region, the captain's age, the captain's career and the age of fishing vessel. As a result of analyzing opinions on the operation status of the coastal improved stow net fishery, it was found that the average time required for casting net was 32.8 to 33.0 minutes and that the average time required for hauling net was 41.0 to 42.2 minutes which took 10 to 12 minutes more than for casting net. The most important work requiring improvement during fishing operation (the first priority) were 'hauling net operation,' 'readjustment and storage of fishing gear,' and 'fish handling' and the hardest factor in fishing management were in the order of 'reduction of catch,' 'labor shortage' and 'rising labor costs.' The most institutional improvement that is most needed in coastal improved stow net fishery was an 'using fine mesh nets.' Most of the respondent to the questions on the experience in hiring foreign crews was 'either hiring or willing to hire foreign crews,' and the average number of foreign crews employed was found to be 2.3 to 2.4 persons. The most important reason for hiring (or considering employment) foreign crews was 'high labor costs.' The degree of communication with foreign crews during fishing operation were 'moderate' or 'difficult to direct work.' The most important problem in hiring foreign crews (the first priority) was an 'illegal departure.' As the survey results on the opinion of structural improvement of coastal improved stow net fishing vessel, the degree of satisfaction with fishing vessel structure related to fishing operation was found to be somewhat unsatisfactory, with an average of 3.3 points on a five-point scale. The inconvenient structure of fishing vessel in possession (the first priority), the space needed most for the construction of new fishing vessel (the first priority) and the space considered important for the construction of new fishing vessel (the first prioprity) was a 'fish warehouse.' The most preferred equipment for the construction of new fishing vessel were 'engine operation monitoring' and 'navigation safety devices.' The average size (tonnage class), the average horse power and the average total length of fishing vessel for proper profit and safety fishing operation was between 13.8 and 14.0 tonnes, 808.3 to 819.5 H.P. and 23.4 to 23.5 meters, respectively. The results of the operation status of coastal improved stow net fishery and the requirement for improving the fishing vessel structure are expected to be provided as basic data for reference when we build or improve the fishing vessel.

Reliable Radiologic Parameters to Predict Surgical Management for Clubfoot Treated with the Ponseti Method (Ponseti 방법으로 치료를 시작한 선천성 만곡족 환자에서 수술적 치료 여부를 예측할 수 있는 방사선적 지표)

  • Song, Kwang Soon;Yon, Chang Jin;Lee, Si Wook;Lee, Yong Ho;Um, Sang Hyun;Kwon, Hyuk Jun
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.1
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    • pp.59-66
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    • 2019
  • Purpose: Several radiologic reference lines have been used to evaluate individuals with a clubfoot but there is no consensus as to which is most reliable. The aim of this study was to identify which radiologic parameters have relevance to the predictability of additional surgery after Ponseti casting on clubfoot and the effect of clubfoot treatments that contain Ponseti casting and additional surgery. Materials and Methods: A total of 102 clubfeet (65 patients, 37 bilateral) were reviewed from 2005 to 2013. The patients were divided into two groups (Group A, those for whom the result of the Ponseti method was successful and did not require additional surgery; and Group B, those for whom the result of the Ponseti method was unsuccessful and required additional surgery), and the following parameters were measured on the plain radiographs: i) talo-calcaneal angle on the anteroposterior and lateral view, ii) talo-1st metatarsal angle on the anteroposterior view, and iii) Tibio-calcaneal angle on the lateral view with the ankle full-dorsiflexion state. Each radiograph was reviewed on two separate occasions by one orthopedic doctor to characterize the intra-observer reliability, and the averages were analyzed. Next, 20 cases were chosen using a random number table, and two orthopedic doctors measured the angle separately to characterize the interobserver reliability. Results: Groups A and B included 73 clubfeet (71.6%) and 29 clubfeet (28.4%), respectively. The initial talo-calcaneal angle and tibiocalcaneal angle in the lateral view were significantly different among the groups. In addition, inter- and intra-observer biases were not detected. The talo-1st metatarsal angle on the anteroposterior view and tibio-calcaneal angle on the lateral view were significantly different after treatment in both groups. Conclusion: Congenital clubfeet treated with the Ponseti method showed successful results in more than 70% of patients. The initial talocalcaneal angle and tibio-calcaneal angle on the lateral view were the radiologic parameters that could predict the need for additional surgical treatments. The talo-1st metatarsal angle on the anteroposterior view and tibio-calcaneal angle on the lateral view could effectively evaluate the changes in clubfoot after treatment.

A Study on the Development of Ultra-precision Small Angle Spindle for Curved Processing of Special Shape Pocket in the Fourth Industrial Revolution of Machine Tools (공작기계의 4차 산업혁명에서 특수한 형상 포켓 곡면가공을 위한 초정밀 소형 앵글 스핀들 개발에 관한 연구)

  • Lee Ji Woong
    • Journal of Practical Engineering Education
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    • v.15 no.1
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    • pp.119-126
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    • 2023
  • Today, in order to improve fuel efficiency and dynamic behavior of automobiles, an era of light weight and simplification of automobile parts is being formed. In order to simplify and design and manufacture the shape of the product, various components are integrated. For example, in order to commercialize three products into one product, product processing is occurring to a very narrow area. In the case of existing parts, precision die casting or casting production is used for processing convenience, and the multi-piece method requires a lot of processes and reduces the precision and strength of the parts. It is very advantageous to manufacture integrally to simplify the processing air and secure the strength of the parts, but if a deep and narrow pocket part needs to be processed, it cannot be processed with the equipment's own spindle. To solve a problem, research on cutting processing is being actively conducted, and multi-axis composite processing technology not only solves this problem. It has many advantages, such as being able to cut into composite shapes that have been difficult to flexibly cut through various processes with one machine tool so far. However, the reality is that expensive equipment increases manufacturing costs and lacks engineers who can operate the machine. In the five-axis cutting processing machine, when producing products with deep and narrow sections, the cycle time increases in product production due to the indirectness of tools, and many problems occur in processing. Therefore, dedicated machine tools and multi-axis composite machines should be used. Alternatively, an angle spindle may be used as a special tool capable of multi-axis composite machining of five or more axes in a three-axis machining center. Various and continuous studies are needed in areas such as processing vibration absorption, low heat generation and operational stability, excellent dimensional stability, and strength securing by using the angle spindle.

Jangdo(Small Ornamental Knives) manufacturing process and restoration research using Odong Inlay application (오동상감(烏銅象嵌)기법을 활용한 장도(粧刀)의 제작기술 및 복원연구)

  • Yun, Yong Hyun;Cho, Nam Chul;Jeong, Yeong Sang;Jang, Chu Nam
    • Korean Journal of Heritage: History & Science
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    • v.49 no.2
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    • pp.172-189
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    • 2016
  • In this research, literature research on the Odong material, mixture ratio, casting method and casting facility was conducted on contemporary documents, such as Cheongong Geamul. Also, a long sword was produced using the Odong inlay technique. The sword reproduction steps were as follows; Odong alloying, silver soldering alloying, Odong plate and Silver plate production, hilt and sheath production, metal frame and decorative elements, such as a Dugup (metal frame), production, Odong inlay assembly and final assembly. For the Odong alloy production, the mixture ratio of the true Odong, which has copper and gold ratio of 20:1, was used. This is traditional ratio for high quality product according to $17^{th}$ century metallurgy instruction manual. The silver soldering alloy was produced with silver and brass(Cu 7 : Zn 3) ratio of 5:1 for inlay purpose and 5:2 ratio for simple welding purpose. The true Odong alloy laminated with silver plate was used to produce hilt and sheath. The alloy went through annealing and forging steps to make it into 0.6 mm thick plate and its backing layer, which is a silver plate, had the matching thickness. After the two plates were adhered, the laminated plate went through annealing, forging, engraving, silver inlaying, shaping, silver welding, finishing and polishing steps. During the Odong colouring process, its red surface turns black by induced corrosion and different hues can be achieved depending on its quality. To accomplish the silver inlay Odong techniques, a Hanji saturated with thirty day old urine is wrapped around a hilt and sheath material, then it is left at warm room temperature for two to three hours. The Odong's surface will turn black when silver inlay remains unchanged. Various scientific analysis were conducted to study composition of recreated Odong panel, silver soldering, silver plate and the colouring agent on Odong's surface. The recreated Odong had average out at Cu 95.57 wt% Au 4.16wt% and Cu 98.04 wt% Au 1.95wt%, when documented ratio in the old record is Cu 95wt% and Au 5wt%. The recreated Odong was prone to surface breakage during manufacturing process unlike material made with composition ratio written in the old record. On the silver plate of the silver and Odong laminate, 100wt% Ag was detected and between the two layers Cu, Ag and Au were detected. This proves that the adhesion between the two layers was successfully achieved. The silver soldering had varied composition of Ag depending on the location. This shows uneven composition of the silver welding. A large quantities of S, that was not initially present, was detected on the surface of the black Odong. This indicates that presence of S has influence on Odong colour. Additional study on the chromaticity, additional chemical compounds and its restoration are needed for the further understanding of the origin of Odong colour. The result of Odong alloy testing and recreation, Odong silver inlay long sword production, scientific analysis of the Odong black colouring agent will form an important foundation of knowledge for conservation of Odong artifact.

Effect of Electron Donor on the Reductive Dechlorination of PCE in Groundwater Using Biobarrier: Batch Experiment (생물벽체를 이용한 지하수내 PCE의 환원성 탈염소화시 전자공여체의 영향: 회분식 실험)

  • HwangBo, Hyun-Wook;Shin, Won-Sik;Kim, Young-Hun;Song, Dong-Ik
    • Journal of Soil and Groundwater Environment
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    • v.11 no.2
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    • pp.22-37
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    • 2006
  • The applicability of biobarrier or in situ microbial filter technology for the remediation of groundwater contaminated with chlorinated solvent was investigated through batch microcosm study. The efficiency and rates of reductive dechlorination of tetrachloroethylene (PCE) are known to be highly dependent on hydrogen concentration. In this study, the effect of electron donors on the reductive dechlorination of PCE was investigated using vermicompost (or worm casting) and peat as a biobarrier medium. The effect of organic acids (lactate, butyrate and benzoate), yeast extract and vitamin $B_{12}$ on the reductive dechlorination was investigated. In the absence of biobarrier medium (adsorbent), addition of electron donors stimulated the dechlorination rate of PCE compared to the control experiment (i.e., no electron donor added). Among the treatments, addition of lactate or lactate/benzoate as hydrogen donor exhibited the highest dechlorination rate ($k_1=0.0260{\sim}0.0266\;day^{-1}$). In case of using vermicompost as a biobarrier medium, amendment of lactate/benzoate exhibited the highest dechlorination rate following with a pseudo-first-order degradation rate constant of $k_1=0.0849\;day^{-1}$. In contrast, when Pahokee peat was used as a biobarrier medium, either butyrate or lactate addition exhibited the highest dechlorination rate with $k_1$ values of 0.1092 and $0.1067\;day^{-1}$, respectively. The results of this study showed the potential applicability of in situ biobarrier technology using vermicompost or peat as a barrier material for the remediation of groundwater contaminated with chlorinated solvent.

Rheology Control of Cement Paste for Applying ECC Produced with Slag Particles to Self-Consolidating and Shotcreting Process (고로슬래그 미분말이 혼입된 자기충전 및 숏크리트용 ECC의 개발을 위한 시멘트풀 레올로지 제어)

  • Park, Seung-Bum;Kim, Jeong-Su;Kim, Yun-Yong
    • Journal of the Korea Concrete Institute
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    • v.20 no.1
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    • pp.67-75
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    • 2008
  • An engineered cementitious composite produced with slag particles (Slag-ECC) had been developed based on micromechanical principle. Base grain ingredients were properly selected, and then the mixture proportion was optimized to be capable of achieving robust tensile ductility in the hardened state. The rheological design is performed in the present study by optimizing the amount of admixtures suitable for self-consolidating casting and shotcreting process in the fresh state. A special focus is placed on the rheological control which is directly applicable to the construction in field, using prepackaged product with all pulverized ingredients. To control the rheological properties of the composite, which possesses different fluid properties to facilitate two types of processing (i.e., self-consolidating and shotcreting processing), the viscosity change of the cement paste suspensions over time was initially investigated, and then the proper dosage of the admixtures in the cement paste was selected. The two types of mixture proportion were then optimized by self-consolidating & shotcreting tests. A series of self-consolidating and shotcreting tests demonstrated excellent self-consolidation property and sprayability of the Slag-ECC. The rheological properties altered through this approach were revealed to be effective in obtaining Slag-ECC hardened properties, represented by pseudo strain-hardening behavior in uniaxial tension, allowing the readily achievement of the desired function of the fresh Slag-ECC. These ductile composites with self-consolidating and shotcreting processing can be broadly utilized for a variety of applications, e.g., in strengthening seismic resistant structures with congested reinforcements, or in repairing deteriorated infrastructures by shotcreting process.