Recently, at-home workouts, which allows people to exercise easily and comfortably at home without going to the gym, has been in the spotlight. Accordingly, a lot of household equipment is produced, but weight exercise equipment is limited in use at home because of its heavy weight or volume. Therefore, this paper proposes a new form of exercise equipment that can be used at home by transforming the exercise equipment used in the fitness center. The proposed mechanism replaces the weight part of the strength exercise device, which is the key to weight control, with an electric motor. Three major muscle exercise instruments (long pull machine, curl cable machine, and let down machine) were analyzed by dynamic analysis using a multipurpose dynamic program (DAFUL). This shows that the proposed equipment can perform various sports. Therefore, the proposed mechanism is expected to be applicable at home, and this study is expected to be rapidly mass-produced by emphasizing practicality.

Recently, home workout has attracted attention as it can be done easily and conveniently at home. Accordingly, many types of home workout equipment are produced but, these kinds of exercise equipment using dumbbells or weights are too heavy to use for at-home-workout and they are too bulky in size. This paper studies a form of exercise done at home which is using a motor instead of dumbbells and weights that are originally used in the exercise equipment. DAFUL, a multi-body dynamics analysis program, is used to verify the dynamic performance of the proposed equipment. Therefore, motor-based exercise equipment is expected to be smaller than existing exercise equipment and more suitable for use at home.

As water resources are limited and legal regulations are strengthened, there is a growing need to reuse residuals in WTP(Water Treatment Plant). In this study, membrane filtration system was constructed and its operation method was studied for water quality stabilization and reuse of WTP residuals. The operation parameters were stable for 1 year and 6 months. Membrane fouling was identified as particulate pollution (activated carbon) and inorganic pollution (manganese). The membrane system was operated steadily with raw water of high concentration SS(Suspended solid) containing activated carbon because membrane fouling was reduced by the effect of End-Free type. In the case of inorganic contamination, dissolved manganese eluted by chemicals and acted as a membrane fouling source, and the operating conditions for minimizing membrane fouling were confirmed by newly developing application methods and types of cleaning chemicals. Based on the results, design parameters for reducing manganese membrane fouling were derived.

본 연구는 Veronica속 20종의 생장 및 개화 특성을 평가하기 위해 2년 동안 국립수목원 식물자원연구과 육종온실에서 수행하였다. Veronica속 식물은 다양한 생장 및 개화 특성을 가지고 있었다. 꼬리풀 20종을 식물 형태 및 초장에 따라 분류하였다. 포복형의 10cm 미만 초장은 V. armena와 V. repens, 직립형 30cm 미만 초장은 V. gentianoides ‘Little blues’ 등 4종, 직립형 30~60cm 사이 초장은 V. gentianoides ‘Blue Streak’ 등 7종, 직립형 60cm 이상 초장은 V. incana 등 7종이었다. 대부분의 엽색은 초록색이었고 V. incana와 V. incana ‘Silbersee’는 잎에 흰 털이 있었다. 꽃대 수는 5.3개부터 80.7개, 화수는 4.5개부터 67.3개였고 개화일은 3월 초순부터 6월 중순이었다. 화서의 형태는 총상화서, 수상화서, 취산화서로 분류하였다. 화색은 보라색 13종, 분홍색 2종, 흰색 5종이었다. 2017년 모든 개체가 개화한 종은 3종으로 V. longifolia ‘Blue Shades’, V. spicata ‘Blue Bouquet’, V. subsessilis ‘Blue Pyramid’였고, 일부 개체만 개화한 종은 7종으로 V. armena, V. gentianoides ‘Little Blues’, V. longifolia ‘Alba’, V. prostrata ‘Nestor’, V. spicata, V. spicata ‘Alba’, V. spicata ‘Sightseeing’ 이었다. 모든 개체가 개화하지 않은 종은 10종으로 V. gentianoides ‘Blue Streak’, V. incana, V. incana ‘Silbersee’, V. longifolia ‘Pink Shades’, V. orchidea ‘Blue Fingers’, V. repens, V. schmidtiana, V. spicata ‘Blue Carpet’, V. spicata ‘Pink Goblin’, V. teucrium ‘Royal Blue’였다. 반면, 2018년에는 모든 종의 개체가 개화하였다.

In this study, the glass melting properties are evaluated to examine the possibility of using refused coal ore as replacement for ceramic materials. To fabricate the glass, refused coal ore with calcium carbonate and sodium carbonate in it (which are added as supplementary materials) is put into an alumina crucible, melted at 1,200 ~ 1,500℃ for 1 hr, and then annealed at 600℃ for 2 hrs. We fabricate a black colored glass. The properties of the glass are measured by XRD (X-ray diffractometry) and TG-DTA (thermogravimetry-differential thermal analysis). Glass samples manufactured at more than 1,300℃ with more than 60 % of refused coal ore are found by XRD to be non-crystalline in nature. In the case of the glass sample with 40 % of refused coal ore, from the sample melted at 1,200℃, a sodium aluminum phosphate peak, a disodium calcium silicate peak, and an unknown peak are observed. On the other hand, in the sample melted at 1,300℃, only the sodium aluminum phosphate peak and unknown peak are observed. And, peak changes that affect crystallization of the glass according to melting temperature are found. Therefore, it is concluded that glass with refused coal ore has good melting conditions at more than 1,200℃ and so can be applied to the construction field for materials such as glass tile, foamed glass panels, etc.

Ink-jet printing is a manufacturing process technology that directly prints a digitalized design pattern onto a substrate using a fine ink jetting system. In this study, environmentally friendly yellow aqueous ceramic ink is synthesized by mixture of distilled water, yellow ceramic pigment and additives for ink-jet printing. The graft polymer, which combines electrostatic repulsion and steric hindrance mechanism, is used as a surfactant for dispersion stability of aqueous ceramic ink. Synthesized ceramic ink with graft polymer surfactant shows better dispersion stability than did ceramic ink with PAA surfactant; synthesized ink also shows desirable ink-jet printability with the formation of a single ink droplet during printability test. Finally, ceramic ink printed on glass substrate and ceramic ink with graft polymer surfactant shows a high contact angle without surface treatment on glass substrate. Consequently, it is confirmed that the ceramic ink with graft polymer surfactant can achieve high printing resolution without additional surface treatment process.

As automation systems become more common, there is growing interest in functional labeling systems using organic and inorganic hybrid materials. Especially, the demand for thermally and chemically stable labeling paper that can be used in a high temperature environment above 300 oC and a strong acid and base atmosphere is increasing. In this study, a composite coating solution for the development of labeling paper with excellent thermal and chemical stability is prepared by mixing a silica inorganic binder and titanium dioxide. The silica inorganic binder is synthesized using a sol-gel process and mixed with titanium dioxide to improve whiteness at high-temperature. Adhesion between the polyimide substrate and the coating layer is secured and the surface properties of the coating layer, including the thermal and chemical stability, are investigated in detail. The effects of the coating solution dispersion on the surface properties of the coating layer are also analyzed. Finally, it is confirmed that the developed functional labeling paper showed excellent printability.

This paper is concerned to develop a fluid pressure system for the control of artificial bladder urine discharge. The primary goal is to force the fluid into the space between the inner wall and the outer wall by using a pump in the artificial bladder having a double structure of inner and outer walls and to form the urine discharge pressure by the contraction of the bladder inner wall due to the movement of the fluid. The ANSYS_CFD analysis is used to confirm the delivery of fluid pressure in the artificial bladder model, and the ANSYS_FSI analysis is used to identify the deformation and internal pressure of the artificial bladder through the delivery of fluid pressure, and to identify the discharge of urine. As the design parameters of the modeling of the artificial bladder and the fluid flow field, the capacity of the flow field, and the pump pressure input value were selected.

Generally, ceramic tiles for building construction are manufactured by dry forming process using granular powders prepared by spray drying process after mixing and grinding of mineral raw materials. In recent years, as the demand for large ceramic tiles with natural texture has increased, the development of granule powders with high packing ratio and excellent flowability has become more important. In this study, ceramic tile granule powders are coated with hydrophobically treated silica nanoparticles. The effects of hydrophobic silica coating on the flowability of granule powders and the strength of the green body are investigated in detail. Silica nanoparticles are hydrophobically treated with GPTMS(3-glycidoxypropyl trimethoxy silane), which is an epoxy-based silane coupling agent. As the coating concentration increases, the angle of repose and the compressibility decrease. The tap density and flowability index increase after silica coating treatment. These results indicate that hydrophobic treatment can improve the flowability of the granular powder, and prevent cracking of green body at high pressure molding.

Recently, the demand of wire quality improvement has been increasing due to the development of the textile market, and the demand for round type flat wire having superior performance compared to the existing reed wire is also increasing greatly. The round wire requires equal spacing and precise alignment of the wire at reed knitting. So, there is a need for a method for measuring the flatness of Reed in real time. In this paper, it is shown how the contact and non - contact methods for the flatness of Reed used in a power loom are easy to measure in real - time process. The contact-type method provides excellent measurement accuracy and precision because it directly touches the object. The non-contact type does not touch the object, so it does not scratch the surface, and the result can be obtained faster than the contact type. Contact type measuring device was used as contact type and laser displacement sensor was used as non - contact type. It was confirmed that the measurement method using the laser displacement sensor (non-contact type) is suitable for the real time process.

In this study, we proposed a model for forecasting power energy demand by investigating how outside temperature at a given time affected power consumption and. To this end, we analyzed the time series of power consumption in terms of the power spectrum and found the periodicities of one day and one week. With these periodicities, we investigated two time series of temperature and power consumption, and found, for a given hour, an approximate linear relation between temperature and power consumption. We adopted an exponential smoothing model to examine the effect of the linearity in forecasting the power demand. In particular, we adjusted the exponential smoothing model by using the variation of power consumption due to temperature change. In this way, the proposed model became a mixture of a time series model and a regression model. We demonstrated that the adjusted model outperformed the exponential smoothing model alone in terms of the mean relative percentage error and the root mean square error in the range of 3%~8% and 4kWh~27kWh, respectively. The results of this study can be used to the energy management system in terms of the effective control of the cross usage of the electric energy together with the outside temperature.

This paper deals with the stability of industrial robot arms with six axes and six degrees of freedom. The robot arm used was IRB120, a product of ABB company, which is used in the real industry, by using the commercial “DAFUL” which is a simulation program that can analyze the dynamic behavior. DAFUL was applied to the robot arm to control the motion by applying the load to the robot arm and then the structural analysis of the robot arm was performed during the analysis time. As a result of the analysis of the robot arm, the stress and displacement acting on the elliptic model and the acting torque and force were analyzed. Based on the analysis results, stability was checked with reference to IRB120 product catalog.

Heat treatment of metals is an necessary process for obtaining properties required for metals. However, the heat treatment sector is labor intensive enough to be classified as an unwanted sector. In particular, in the case of quenching during the heat treatment, in order to select the defective product due to the collision caused by the collision between the products when the product is dropped in the oil tank during the quenching process, the labor is not concentrated on the heat treatment as the main process, It is a fact that it is put in. In this paper, in order to solve the labor - intensive nature, this paper designed and tested prototype products for the selection of defective products during the heat treatment process of the ball stud. The ball stud inspection device is divided into two parts, a ball stud supply device and an inspection device, and describes the concept design and prototype production contents. The performance of the prototype was evaluated by examining 1000 samples with 5 items. The manufactured ball stud inspection system will contribute to the relaxation of the avoidance phenomenon of the heat treatment industry and contribute to the efficiency and competitiveness of the work.

수영만 해역의 오염원 관리를 위해 유입되는 육상기인 오염물질의 체류특성을 분석하였다. 오염물질의 체류특성은 해수유동 모델과 입자추적 모델을 활용하여 분석하였다. 오염물질은 입자로 표현되며, 입자의 양과 오염물질량은 비례하도록 나타내었다. 체류특성은 각 오염원별로 부하량, 해역에서 체류하는 오염물질량, 부하량 대비 해역에 체류하는 오염물질량을 비교하여 분석하였다. 수영만 해역에 체류하고 있는 오염물질량을 오염원별 순으로 나타내면 수영하수처리장, 남부하수처리장, 수영강 등의 순이었다. 오염부하량이 적고 만 내측에서 멀어질수록 해역에 체류하는 오염물질량이 적었다. 오염원 중에서는 남부하수처리장에서 유입되는 부하량이 가장 많았다. 하지만, 유입 부하량 대비 해역에 체류하는 오염물질량은 수영만으로 유입되는 오염원 중 가장 낮은 값을 보였다. 이는, 해역의 특성과 각 오염원의 지형적인 특성에 따라 오염물질이 해역에 미치는 정도가 다르다는 것을 의미한다.

Three-dimensional(3D) printing is a process for producing complex-shaped 3D objects by repeatedly stacking thin layers according to digital information designed in 3D structures. 3D printing can be classified based on the method and material of additive manufacturing process. Among the various 3D printing methods, digital light processing is an additive manufacturing technique which can fabricate complex 3D structures with high accuracy. Recently, there have been many efforts to use ceramic material for an additive manufacturing process. Generally, ceramic material shows low processability due to its high hardness and strength. The introduction of additive manufacturing techniques into the fabrication of ceramics will improve the low processability and enable the fabrication of complex shapes and parts. In this study, we synthesize silica composite material that can be applied to digital light processing. The rheological and photopolymeric properties of the synthesized silica composite are investigated in detail. 3D objects are also successfully produced using the silica composite and digital light processing.

In this study, glass fibers are fabricated via a continuous spinning process using manganese slag, steel slag, and silica stone. To fabricate the glass fibers, raw materials are put into an alumina crucible, melted at 1550℃ for 2 hrs, and then annealed at 600℃ for 2 hrs. We obtain a black colored glass. We identify the non-crystalline nature of the glass using an XRD(x-ray diffractometer) graph. An adaptable temperature for spinning of the bulk marble glass is characterized using a high temperature viscometer. Spinning is carried out using direct melting spinning equipment as a function of the fiberizing temperature in the range of 1109℃ to 1166℃ , while the winder speed is in the range of 100rpm to 250rpm. We investigate the various properties of glass fibers. The average diameters of the glass fibers are measured by optical microscope and FE-SEM. The average diameter of the glass fibers is 73 μm at 100rpm, 65 μm at 150rpm, 55 μm at 200rpm, and 45 μm at 250rpm. The mechanical properties of the fibers are confirmed using a UTM(Universal materials testing machine). The average tensile strength of the glass fibers is 21MPa at 100rpm, 31MPa at 150rpm, 34MPa at 200rpm, and 45MPa at 250rpm.

Anti-reflection thin films are fabricated on glass substrates using the screen printing method. Tetra ethyl silicate(TEOS) and methyl tri methoxy silane(MTMS) are used as starting materials and buthyl carbitol acetate(BCA) and buthyl cellusolve(BC) are mixed to improve the viscosity of the solution. Anti-reflection thin films are fabricated according to the number of the screen mesh and the characteristics improve as the mesh size increases. The transmittance and reflectance of the coated thin film using 325 mesh are about 94 % and 0.43 % in the visible wavelength. The thickness and refractive index of the AR thin film are 107 nm and n = 1.26, respectively.