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Recently, as the damage of air pollution due to fine dusts, etc. has been continuously increased, there is a growing need for a low-cost air quality monitoring system to observe air pollution information at public facilities or homes. In this paper, we propose an IoT (Internet of Things)-based atmospheric environment monitoring system which can effectively observe air pollution information without restriction of place or space. The proposed system consists of an atmospheric environment measuring device and an atmospheric environment analyzer, in which the system has been developed to be able to collect and analyze atmospheric environment measurement results in a server through an LTE communication network. The atmospheric environment information obtained from the development system was compared with the observation results provided by the National Ambient air quality Monitoring Information System (NAMIS).

nowadays, vehicles have become a very significant role in transport which remain a major problem in most cities around the world, especially in developing regions resulting in massive delays, turn traffic congestion, increased fuel wastage and monetary losses. There are many alternative systems, but one possible solution to this problem is parking system has become the sparking factors of the mentioned problems above. In this paper, we present various techniques as far as the smart parking system is mainly debated which are already implemented. When we are deepening into this parking issue, many contributors contributed a lot in monitoring smart parking system (SPS) and management of SPS with an asset of various gadgets and technologies including Bluetooth, Cameras, Image Processing, wireless sensors, ZigBeee accompanied by software explanations based on mobile application. Following this analysis will enhance researcher's thought on SPS which will result in a real solution of the technique.

In this paper, we propose disparity map acquisition of high definition image using CUDA with new search range estimation algorithm. Our proposed search range estimation method uses SSD with processing in gray scale image only. To perform high speed computation of disparity map, we used shared memory in CUDA, and utilize SSD as a matching algorithm to apply for a 9 by 9 window to 1240×1110 image, with using search range length of 250. Our experimental results showed that our method achieved 31fps on the average using NVIDIA GeForce 770.

In this paper, we presents a technique for recognizing object in robot manufacturing automation system with block matching algorithm that is simple to implement, but slow. To reduce the processing time of block matching algorithm, we propose an object recognition with GPGPU model. As experimental validation indicates, our scheme achieved a better performance in terms of processing time compared with the existing method.

This paper presents a method of reducing visual fatigue for 3D image viewing. We, based on Epipolar geometry, compare with the conventional method focusing on adjusting baseline of image. Our unique idea is that the scaling of baseline is used to adjust the disparity of the left and right images to reduce visual fatigue. The experimental validation indicates that our proposed method can be adopted as a reliable method to reduce visual fatigue in the 3D image.

This paper presents a Ring Projection Transforms (RPT) for recognizing an object in automation system. Based on the Coarse-fine strategy and Compute Unified Device Architecture (CUDA), we developed a recognition model on GPGPU (General-Purpose computing on Graphics Processing Units) scheme. As experimental validation indicates, our scheme achieved a better performance in terms of processing time compared with the existing method.

As the use of ACFs has increased in electronic packaging applications, demands for highly reliable ACFs has been also increased. For this demand, solder ACFs which use solder particles as conductive particles of ACFs has been previously introduced combined with an ultrasonic bonding method. In the solder ACFs bonding, solders are melted simultaneously with polymer resin curing reaction and the solder particles between two metal electrodes form various solder joint morphologies depending on the ACF resin curing characteristics. Furthermore, the solder joint morphologies between two metal electrodes can affect the ACF joint reliability at high temperature and high humidity reliability conditions. Therefore, the study on the morphology control of solder ACF joints and understanding the solder crack initiation and propagation during the reliability tests are needed for the highly reliable solder ACFs bonding. In this study, to understand the formation of solder morphology during solder ACFs bonding process, in-situ ACF resin viscosity was investigated. In-situ ACF resin viscosity can be predicted by the fitted equation at the specific temperatures. Resin viscosity at specific temperatures increased as degree of cure of ACF resin increased with the S-shaped growth curve, which was fitted with the Boltzmann equation. From the fitted equation, the ACF resin viscosity can be predicted at solder melting point (MP). Using this prediction, the effects of resin properties on solder morphologies were investigated. Slow curing acrylic ACFs showed concave shaped solder joints with larger spreading of solder particles due to the lower viscosity of resin surrounding solder particles. The degree of cure of slow curing acrylic ACFs at the solder MP was lower compared with that of conventional acrylic ACFs. In terms of resin viscosity, lower viscosity epoxy resin showed concave shaped solder joints because of lower viscosity at the solder MP compared with that of conventional acrylic resin which showed convex shaped solder joints. Solder joints bonded with slow curing acrylic ACFs and low viscosity epoxy ACFs showed higher reliability than that of solder joints with conventional acrylic ACFs, because solder joints with slow curing ACFs and lower viscosity epoxy ACFs formed concave shaped solder joints resulting in lower stress concentration due to larger curvatures of stress concentration regions than that of conventional acrylic ACFs.

In this study, self-fluxing additives were added in solder anisotropic conductive films (ACFs) in order to eliminate solder oxide resulting in an excellent solder wetting on metal pads during ACF bonding. Since the solder oxide causes poor wettability of solder particles, solder oxide was chemically removed by self-fluxing additives in solder ACFs. The test boards were 25 μm-thick polyimide based FPCs and 1 mm-thick FR-4 organic rigid PCBs which have 400 μm pitch Cu patterns with electroless nickel and immersion gold (ENIG) surface finish. Newly formulated solder ACFs were acrylic based adhesives film which can be fully cured above 150°C containing self-fluxing additives. The film contained 25 μm diameter Sn58Bi particles which has 138°C melting point and 8 μm diameter Ni particles as a spacer to maintain the gap between metal electrodes. According to the experimental results, the addition of self-fluxing additive caused significant improvement of solder wettability and reliability of solder ACF joints. Therefore, using a flux function added solder ACFs can be used for various applications such as FOB and FOF assemblies, and can provide an alternative interconnection method for high power and fine pitch assemblies for many other applications.

In this study, in order to improve thermal stability and reliability of camera module assembly for high yield rate, the camera module assembly using low temperature curable acrylic solder ACFs with ultrasonic-assisted thermo-compression (TC) bonding has been introduced. In general, the acrylic-based ACFs are cured at lower bonding temperature than conventionally used epoxy-based ACFs. And, the recently adopted ultrasonic-assisted TC bonding utilizes ultrasonic vibration during vertical thermo-compression to break solder oxide layers. Bonded solder ACF joints of camera modules for this study were investigated in terms of curing behavior, peel adhesion strength, and solder wetting. In addition, thermal stability of internal camera module assembly at this bonding condition was also investigated. According to the experiment results, acrylic-based solder ACF joints showed peel adhesion strength above recommendation with full degree of cure and excellent solder wetting on the electrodes at the low bonding temperature of 150°C and the ultrasonic amplitude of 6 μm. At the bonding temperature of 150°C, the internal temperature of a camera module was about 110°C which was lower than 137°C, the glass transition temperature of the lens. Therefore, the low temperature curable acrylic-solder ACFs with ultrasonic-assisted TC bonding is appropriate for the camera modules, since the ACFs were optimized in terms of degree of cure, peel adhesion strength and solder wetting and the camera modules were thermally stable at the low bonding temperature of 150°C.

In this study, flux function added solder ACF was proposed in order to be used not only with the ultrasonic bonding method which can break solder using ultrasonic vibration oxides but also with conventional thermo-compression bonding method. Since the solder oxides cannot be broken only with conventional thermo-compression method, we had to remove the oxide chemically. The test vehicles were consist of polyimide based flexible substrates and FR-4 organic rigid boards which have 300 μm pitch Cu patterns with electroless nickel immersion gold (ENIG) surface finish. Solder ACFs 50 μm thick were epoxy based adhesive films containing flux functional additive. The films contain 5-15 μm diameter SAC305 (96.5Sn-3.0Ag-0.5Cu) solder particles which are used as conductive particles and 5 μm diameter Au coated Ni particles which are used as spacers. According to the experimental results, the flux functional additive did not change the curing reaction of the solder ACF. Moreover, the addition of flux functional additive caused significant improvement of electrical properties of solder ACF joints such as power handling capability and reliability. Therefore, using a flux function added solder ACFs can be used for various FOB and FOF assemblies and can provide an alternative interconnection for high power and fine pitch assemblies.

Immersion of substrates in a dilute aqueous solution of bio-inspired building blocks resulted a deposition of polydopamine thin film on the substrate. The Self-polymerization speed measured by ellipsometry was 1.6 nm/hr. Strong catalyst was added in order to enhance the speed. The resulting speed was increased from 1.6 nm/hr to 30 nm/hr. Bio-inspired surface treated PET and ITO-PET substrates with various treatment times were assembled with FPC using commercial acrylic ACF. As a result, adhesion strength between PET substrates and FPC was enhanced dramatically from below 10 gf/cm to over 500 gf/cm even when the treatment time was 5 min. Electrical contact resistance did not show any notable changes. It was presumably due to the sufficiently low thickness (2.5 nm) of bio-inspired thin film on the electrode.

In this study, bonding time for touch screen panel (TSP) assemblies were reduced by two third using an ultrasonic (U/S) horn which fits the shape of the entire TSP bonding area. Most TSPs have at least two bonding areas on the substrates with different heights due to structural design of touch sensing. Using conventional thermo-compression anisotropic conductive film (ACF) bonding, each bonding area should be separately bonded to perform suitable interconnections with uniform pressure and a temperature due to the step height among the bonding areas. However, in U/S bonding, the bonding area could be bonded all at the same time using the U/S horn which fits the bonding area. The test vehicles were capacitive TSPs which consist of three layers of polyethylene terephthalate (PET) substrates. The TSP had three separated bonding areas. Two of them were on the double layer PET substrate. The other one located in the middle of the whole bonding area was on the single layer PET substrate. Therefore, the middle bonding area was 210 μm lower than the other two bonding areas. This complicated TSP structure requires three separate ACF bonding using conventional ACF bonding method. When using a fitted U/S horn, the in-situ ACF temperatures for all bonding areas showed negligible deviation less than 5°C. After U/S bonding for 15 seconds at 2 MPa bonding pressure and 150°C ACF temperature, the adhesion strength of the ACF joint was higher than 650 gf/cm. No damage was observed on the electrode and the substrate. Also, the ACF joints had stable electrical continuities. In conclusion, U/S ACF bonding with fitted horn was successfully demonstrated for high productivity TSP assemblies.

Glass has long been used for photovoltaic (PV) module covers and thin-film (TF) module substrates and superstrates. These applications typically use float glass of soda-lime-silica composition and thickness ≥ 3.2 mm. Thin specialty glass is being considered as a replacement for substrates and superstrates for dual-glass laminated TF PV modules. This study focuses on module in-service stresses and their impact on mechanical reliability when using thin specialty glass. Substrate and superstrate thicknesses as low as 0.7 mm were analyzed using various support conditions. Hail impact tests were conducted according to IEC 61646 with standard ice balls (25mm diameter at 23 m/sec). Wind and snow loads as described in IEC 61646 were studied by finite element analysis. Reliability analyses were performed using experimental results, modeled stress levels, initial glass strength, and strength decrease over time (fatigue). This study concludes that thin specialty glass is reliable in the variety of configurations analyzed. Wind and snow load stresses increased systematically as glass thickness decreased. However, support structure configuration showed a greater influence on stress and reliability levels than glass thickness. High speed wind tests on full sized laminates with complete support structures provided validation of performance under realistic conditions. Thin specialty glasses are shown to be a reliable option for thin-film photovoltaic module substrates and superstrates.

In this study, the effects of vertical ultrasonic (VUS) bonding parameters such as vibration amplitudes and bonding pressures were investigated and optimized in terms of thermal deformation of TSP polymer substrates, electrical continuity, and pull adhesion strength of anisotropic conductive adhesive (ACA) joints. And the reliability of VUS bonded TSP ACA joints were evaluated at various test conditions. As the vertical ultrasonic vibration was applied, ACA temperatures rapidly increased due to the spontaneous heat generation in the ACA itself and surrounding polymers. The ultrasonic vibration showed significant effects on the peak temperature of the ACA layers, and the bonding pressure affected the heating rates. By adjusting both ultrasonic vibration and bonding pressure, the ACA temperature could be successfully controlled. In terms of thermal deformation, VUS bonding showed no severe thermal deformation of TSPs up to 120°C which is much higher than the Tg of polyethylene terephthalates (PETs) which are the base material of TSPs. In terms of electrical continuity of the ACA joints, VUS bonded TSPs showed stable electrical resistances at 2 MPa bonding pressures, and there were no significant effects of vibration amplitudes and bonding times on contact resistances. At the same time, VUS bonded TSPs showed strong adhesion at the ACA joints with 1 second bonding time at 7.5 um vibration amplitude and 2 MPa bonding pressure. During the FPCB pull test, VUS bonded TSPs showed higher than 3 kgf pull strengths. Therefore, VUS bonding parameters were optimized at 7.5 um vibration amplitude, 2 MPa bonding pressure, and 1 second bonding time in terms of PET thermal deformation, electrical continuity and pull adhesion strength of the TSP ACA joints. With the optimized parameters, various reliability tests were conducted such as thermal shock test, salt spray test, high temperature/high humidity test, high temperature storage test and writing test. After each test, the VUS bonded TSPs showed no significant changes in electrical resistance compared with those of thermo-compression bonding. As a summary, the VUS method can be successfully used in TSPs assembly with no thermal damages, higher speed assembly and good reliability.

Based on customer information, data relating to details of financing and payment histories from a financial institution, we derived single models using multilayer perceptions model(MLP), multiple discriminant analysis(MDA), and decision tree model(DTM). The results obtained from these single models were subsequently compared with the results from an integrated model that was developed using genetic algorithm. This study not only verifies existing single models and but also attempts to overcome the limitations of these approaches. While our comparative analysis of single models for the purpose of identifying the best-fit model relies upon existing techniques, this study presents a new methodology to build an integrated approach using data mining and genetic algorithm.

For resolving the manipulator redundancy under inequality constraints, the compact QP method (including the improved Compact QP method) is very effective and efficient. From a viewpoint of practical applications, however, it turns out, we found, to have some performance limitations such as unrealistically high torque due to joint angle limit constraints and tracking errors due to joint torque limit constraints under parameter variation and disturbance. Remedying the limitations, the enhanced compact QP method is developed by using the practical inequality constraints with p-step-ahead predictor and time delay estimation. Through dynamic simulation results, it is verified that the enhanced compact QP method significantly improves the compact QP method in terms of efficiency and effectiveness for the real-time control of redundant manipulators under physical limits.

In telerobot systems, visual servoing of a task object for a slave arm with an eye-in-hand camera has drawn an interesting attention. As such a task is generally conducted in an unstructured environment, it is very difficult to define the inverse feature Jacobian matrix. To overcome this difficulty, this paper proposes an auto-tuning fuzzy rule-based visual servo algorithm. In this algorithm, a visual servo controller composed of fuzzy rules, receives feature errors as inputs and generates the change of slave position as outputs. The fuzzy rules are tuned by using steepest gradient method of the cost function, which is defined as a quadratic function of feature errors. Since the fuzzy rules are tuned automatically, this method can be applied to the visual servoing of a slave arm in real time. The effectiveness of the proposed algorithm is verified through a series of simulations and experiments.