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We evaluated the outcomes of precontoured locking plate fixation with the anconeus flap transolecranon (AFT) approach to treating AO type C2-3 comminuted intra-articular distal humerus (IDH) fractures among active patients. Thirty-six patients (age Orthopedics . 2022;45(6):e326–e334.]

We have developed a carbon nanotube (CNT) pad to replace carbon black, which is essential for electric muscle stimulation (EMS) suits that can provide efficient exercise effects in a short time. The optimized CNT pad had 10 times lower concentration but showed 20 times lower resistance than the carbon black pad. In the case of the peak voltage indicating the EMS performance, it was confirmed that the CNT (4.0 wt%) was 25.9 V and the carbon black (40 wt%) was 6.5 V, which was about 4 times better. CNT added increased from 4.0 wt% to 10.0 wt%, and the peak voltage increased from 25.9 V to 26.8 V, but the output voltage was not significantly improved compared to the amount of CNT added. These experimental results are expected to show higher EMS properties than carbon black because carbon nanotubes and silicon are agglomerated to form a particle-like shape.

In the field of piezoelectric energy harvesting, a cantilever is widely used in a piezoelectric energy harvester (PEH) because it easily deforms under various forces and, generally, the output of the cantilever increases proportionally with the deformation. Naturally, many previous studies focused on how to obtain a higher PEH output. However, the power of the input source is limited, so the efficiency of the PEH must be maximized. In this study, based on the amount of input energy, the existence of an optimal efficiency of energy conversion in the PEH was researched. A plate-type PEH was first installed as the cantilever, and various masses were suspended from the free end of the PEH by using a thread. Next, the thread was cut while the PEH was in a bending state. Immediately, the PEH began vibrating with the input energy being the potential energy of the bent PEH, and the output was obtained. A maximum efficiency of 15.58% was determined in three ways: via the output electrical energy (0.46 mJ), the input potential energy (2.94 mJ), and the deflection value (at a free end position of 3.75 mm). Finally, the existence of the optimal efficiency based on the amount of input energy was found in this PEH.

We propose a piezoelectric energy harvesting technology installed in a roadway speed bump. We have installed a module that can charge mobile phones utilizing a speed bump piezoelectric harvester (SBPH), which is easy to apply to roads. A highly integrated module with 40 piezo-generators was fixed and installed at the center of the speed bump. When a medium-sized vehicle passed the module at a speed of 30 km/h, an output voltage of 144 Vmax, output current of 45.2 mAmax, and output power of 4086.08 mWmax (6.81 W/m2) were measured at a load resistance of 2 kΩ. When the vehicle passed over the SBPH nine times, it charged a capacitor (10,000 μF) to provide 6 V for about 200 s, and the charged electrical energy was enough to operate a cellphone. The self-controlled battery charging system via electricity generated by the piezoelectric module could be applied to a speed bump installed on an actual road.

The power generated by the designed piezoelectric energy harvester replaces the standby power that is constantly used in sensors and driving circuits in commercial LED shoes; the harvester thus reduces battery consumption. LED shoes incorporating a piezoelectric energy harvester are designed for night workers who work near roads. The piezoelectric energy harvester, composed of a piezoelectric device (PZT ceramic), which is inserted under the insoles of shoes, converts mechanical energy generated by motion of user into electrical energy. The designed harvester has an area of 6 × 4 mm and height of 3 mm (pressed state); it weighs 14 g. Because of its small size and light weight, device is suitable for real workers’ shoes. This piezoelectric energy harvester produces 800 μW at a resistive matching point of 400 kΩ; it is used as a sensor to control an LED switching circuit, allowing the LEDs to blink based on user movements. By applying the piezoelectric energy harvester to LED shoes, battery usage time can be doubled compared to LED shoes that are turned on continuously.

Piezoelectric energy harvesting technology can be used for a wide range of purposes through the design of road energy harvesting devices. For the roadway piezoelectric energy harvester (RPEH) developed here, a piezoelectric energy harvester (PEH) is fixed at both ends to increase the tolerable load and a module durable against harsh highway environments were developed using aluminum plates, steel plates, and polypropylene bars. A maximum voltage of 66 V, maximum current of 30.37 mA and maximum output power of 830 mW were measured with 2 mm of displacement at 15 Hz using the RPEH (50 cm × 20 cm) with 80 PEH units connected in parallel. On an actual high-speed road, measurements from a medium-sized vehicle which passes the RPEH at a speed of 90 km/h record an output voltage of 46.52 Vmax, output current of 93.04 mAmax, and power of 4.3 Wmax (power density: 43.0 W/m2) at a load resistance level of 0.5 kΩ. In an actual roadway environment, the electrical energy generated by the RPEH is sufficient to operate a temperature sensor and to transmit data wirelessly.

The purpose of this research was to demonstrate a road-compatible piezoelectric energy harvester (RPEH) that uses the energy to power self-powered sensors and vehicle indicators. The demonstrated RPEH (20 × 50 × 10 cm3) with 80 piezoelectric devices can efficiently convert mechanical energy stemming from the small vertical displacement (1.45 mm) from vehicles into electrical power. The maximum voltage is 113.5 V, the maximum current is 25.71 mA, and the maximum power is 661 mW (6.61 W/m2) at an impedance resistance level of 0.9 kΩ under a z-axial load. The high-power RPEH was initially installed at a highway rest area. The measured output performances of the installed module on the actual roadway in the test setup area were a maximum voltage of 196 V and output power of 2080 mW (20.79 W/m2) at a vehicle speed of 30 km/h. Tests of the RPEH module demonstrate its ability to measure temperature, strain, and leakage values in real time and the generated energy provides sufficient power to illuminate LED indicators. It was also found that the z-axial loaded piezoelectric devices with a two-end fixed beam provide high output power with low levels of vertical displacement, making it highly efficient and durable for actual highway energy-harvesting applications.

This paper introduces a fiber generator using PVDF with a high-performance lead-free piezoelectric ceramic as filler. The piezoelectric ceramic filler was Ba0.84Ca0.16Ti0.90Zr0.10O3 + CuO 0.25 wt% (BCTZC0.25) sintered at 1550 °C. The BCTZC0.25 has an improved high-energy conversion constant (d33 × g33). The fiber generator made of PVDF/BCTZC0.25 composite fiber showed 1.6 times better piezoelectric power generation performance compared to a pure PVDF fiber generator. The PVDF/BCTZC0.25 fiber generator produced an output voltage of 1.9 V at 4 Hz. Hence, we successfully demonstrated that a composite fiber generator that uses piezoelectric ceramics which are harmless to the human body can outperform a pure PVDF fiber generator.

Piezoelectric energy harvesters have attracted much attention because they are crucial in portable industrial applications. Here, we report on a high-power device based on a magneto-mechanical piezoelectric energy harvester to scavenge the AC magnetic field from a power-line cable for industrial applications. The electrical output performance of the harvester (×4 layers) reached an output voltage of 60.8 Vmax, an output power of 215 mWmax (98 mWrms), and a power density of 94.5 mWmax/cm3 (43.5 mWrms/cm3) at an impedance matching of 5 kΩ under a magnetic field of 80 μT. The multilayer energy harvester enables high-output performance, presenting an obvious advantage given this improved level of output power. Finite element simulations were also performed to support the experimental observations. The generator was successfully used to power a wireless sensor network (WSN) for use on an IoT device composed of a temperature sensor in a thermal power station. The result shows that the magneto-mechanical piezoelectric energy harvester (MPEH) demonstrated is capable of meeting the requirements of self-powered monitoring systems under a small magnetic field, and is quite promising for use in actual industrial applications.

A piezoelectric sensor is a typical self-powered sensor. With the advantages of a high sensitivity, high frequency band, high signal-to-noise ratio, simple structure, light weight, and reliable operation, it has gradually been applied to the field of smart wearable devices. Here, we first report a flexible piezoelectric sensor (FPS) based on tungsten disulfide (WS2) monolayers that generate electricity when subjected to human movement. The generator maximum voltage was 2.26 V, and the produced energy was 55.45 μJ of the electrical charge on the capacitor (capacity: 220 μF) when applying periodic pressing by 13 kg. The generator demonstrated here can meet the requirements of human motion energy because it generates an average voltage of 7.74 V (a knee), 8.7 V (a sole), and 4.58 V (an elbow) when used on a running human (weight: 75 kg). Output voltages embody distinct patterns for different human parts, the movement-recognition capability of the cellphone application. This generator is quite promising for smart sensors in human–machine interaction detecting personal movement.

This article presents a high-performance lead-free piezoelectric energy harvester (LPEH) system for magnetic field. It based on a Ba0.85Ca0.15Ti0.90Zr0.10O3 + CuO 0.3 wt% (BCTZC0.3) composite was fabricated by sintering at 1450 °C. The BCTZC0.3 composite, which has an enhanced high energy conversion constant (), shows improved piezoelectric power-generation performance when compared with conventional piezoelectric energy harvesters. The BCTZC0.3-based LPEH produces instantaneous maximum power of 8.2 mW and an energy density of 107.9 mW/cm3 in a weak magnetic field of 250 μT. This system can be used to charge a capacitor and operate a wireless sensor network (WSN) system to provide temperature sensing and radio-frequency (RF) transmission in a 250 μT magnetic field. The proposed LPEH is a promising green-energy device for potentially self-powering WSN systems when applied.

For the development and application of wearable electronics, a transparent and flexible piezoelectric sensor (TFPS) system is an important component considering the physical motion energy of the human body. This work newly proposes a transparent and biocompatible boron nitride nanosheet (BNNS) material with a TFPS device. The TFPS device is based on BNNS as a piezoelectric active component and PDMS as a flexible element. The device is able to generate electrical energy from mechanical push force and human movement; it has an output voltage of 22 V, output current of 75 nA, output power of 40 µW (power density: 106 μW/cm3), and energy conversion efficiency of 12.6%. In addition, the TFPS device based on BNNS (1.0 wt%) is proposed as a significant step toward devices which are self-powered by the biomechanical movement of the human foot, neck, wrist, and knee, converted into electric energy in various signal forms. It will be deployed as a body-movement sensor.

One factor in the energy management of smart home is based upon the location of the home occupants. This location information then can be used to control various electrical and electronic devices and appliances. A floor tile is presented which can be used at different locations in the home and can generate enough energy to wirelessly transmit the information to electrical appliance when a person steps on it. In this work, a novel piezoelectric material system of 0.72Pb(Zr0.47Ti0.53)O3-0.28Pb[(Zn0.45Ni0.55)1/3Nb2/3]O3 + x mol% CuO (PZNxC) was designed, and the energy harvesting characteristics were tailored through composition driven phase boundary evolution. The rhombohedral-tetragonal phase boundary is the best performance area in terms of energy harvesting, which exhibits an obvious advantage in regards to stable energy harvesting. When a person steps on the floor tile, the peak output voltage and current of 42 V and 11 μA, was generated. This energy is then utilized to power a wireless sensor node which can control the power on and off function of home appliances in a real-time.

A smart lighting system can be controlled using a smartphone and/or human activated wireless remote switches. We designed a wireless remote switch using a cantilever type piezoelectric energy harvester to make a battery-less IoT node device that has high output power but a small tip displacement through frequency up-conversion. The purpose of this design is to overcome the conventional volume problem of the piezoelectric cantilever beam. In order to apply the high resonance frequency to the model at constant displacement, we set the limiting conditions of maximum vertical displacement of the cantilever beam to be 1 mm and a human input pressing force of 5–8 N, the force generally required when a human presses a switch button. In these limiting conditions, different shapes of steel substrate were used to find the optimal harvester that meets the limiting conditions and generates about 65 μJ of energy at 5 kΩ resistive loads under free vibration. Using this harvester, we designed a wireless remote switch with an impact type mechanical mechanism with two cantilever type energy harvesters to generate 140 μJ of energy, requiring no impedance matching circuit. This energy was then used to power a microcontroller to transmit data packets using ZigBee Green Power communication. Three identical data packets were transmitted by the wireless remote control switch to ensure data reception by the smart LED bulb and to toggle the bulb on or off state. Finally, this study successfully contributed to elevating the possibility of commercialization of the piezoelectric harvester based wireless remote switch for IoT.

A self-powered energy harvester for real roads to predict and detect black ice formation and pinpoint dangerous road sections was developed. An open-type piezoelectric device was developed for a high-efficiency module to achieve uniform stress distribution for enhanced energy harvesting performance by free-fixed-end type central strike mechanism. The output performance of the open-type device was 80% higher than that of the closed-type device. A uniform stress distribution road piezoelectric generator (URPG) with 120 open-type devices was installed on real roads. The URPG showed output power performance of up to 2.38 mW/cm3 when a vehicle passed once under the condition of being buried 2.5 cm below the road surface. The URPG can operate a wireless temperature sensor monitoring system for 83 s and charge a cellphone battery for 53 s. The developed self-powered energy harvesters can be used to reduce accidents caused by black ice on real roads.

Magneto piezoelectric harvesters (MPHs) operating under an AC magnetic field have attracted much attention due to their vital importance in portable industrial applications. Here, we present the first report of a spring-supported magneto piezoelectric harvester (SMPH) operating under an AC magnetic field to generate enhanced electric performance. As the length of the spring supporting the MPH becomes longer, the elasticity coefficient (N/mm) becomes lower and the resonance frequency decreases. In order to implement SMPH at a resonance frequency of 60 Hz, a spring with spring constant of 24.52 N/mm is used to support the MPH and produce maximum output power. To increase the output power of the SMPH, a magnetic tip was used to scavenge the AC magnetic field. The electrical performance of the SMPH with the magnetic tip mass showed an output voltage of 12.5 Vmax, output current of 654 μAmax, and output power of 5.56 mWmax at a load resistance of 30 kΩ and AC magnetic field of 80 μT. The SMPH exhibits an advantage over the conventional rigidly supported MPH with regards to output power. The demonstrated device is capable of meeting the requirements of charging and operating a wireless temperature sensor system, and thus it is most suitable for use in actual industrial sites where such magnetic fields exist.

We fabricated a spring-supported piezoelectric unimorph cantilever (SPUC) with enhanced energy-harvesting characteristics by using a 0.69Pb(Zr0.47Ti0.53)O3–0.31Pb(Ni0.6Zn0.4)1/3Nb2/3)O3 + CuO (0.5 mol%) thick film sintered at 950 °C; a spring having a spring constant of 14,320 N/m was used as the cantilever support. The SPUC could generate an output power as high as 29 mW with a spring constant of 14,320 N/m across a resistance of 150 kΩ; this corresponded to a power density of 34 mW/cm3. We, therefore, that the thus-fabricated SPUCs when supported by a spring can harvest increased levels of energy.

We demonstrate the use of a road-capable piezoelectric harvester (RCPH) with improved maintenance and power-generation characteristics. The RCPH obtained its ingress and moisture protection system rating (IP 66) through a new housing system used to evaluate its waterproof performance. Finite element simulations were performed to identify the proper depth (1, 3, or 5 cm) under an actual road for its placement to achieve increased output power. The highest von Mises stress value was measured by the 1 cm landfilled module (1LFM). The RCPH was installed under a test road and was tested with the use of the exposed and landfilled method to compare output power levels. Correspondingly, the output voltage and output power of the 1LFM were higher the exposed module. When a minivan drove over the 1LFM at 90 km/h, an output voltage of 18 Vmax and an output power of 1150 mWmax (power density: 1.15 mW/cm2) were measured at a load resistance level of 910 Ω. In a test road environment, the electrical energy generated by the 1LFM was sufficient to illuminate four delineators for 40 s. This system could be used on actual roads by connecting the piezoelectric modules to an emergency lighting that can be powered by the electricity generated by the module.

We propose a pavement block piezoelectric energy harvester (PBPEH) that can be installed in an actual walkway. We developed an Internet of Things (IoT) system that can power the walkway signal indicator (delineator) and also collect environmental data (such as humidity and temperature) near the walkway utilizing the PBPEH, without a battery. A highly integrated module with 24 piezoelectric devices were fixed inside the PBPEH. Under maximum weight condition, that is, in case of a person weighing 100 kg passing over the module, an output voltage of 38.52 Vmax, current of 3.85 mAmax, and power of 148.3 mWmax (3.7 W/m2) were generated at a load resistance of 10 kΩ. Energy storage test as applied to realistic conditions, that is, when a 60 kg person (average weight condition) passes over the module 10 times it charged a capacitor (1000 μF) to 55.6 mJ. As a result, it successfully turned on a delineator installed on an actual walkway after 4.8 s and powered the IoT sensor system without an external energy source.

Unlike previous piezoelectric energy harvesters that generate electrical energy from a magnetic field according to the magnetic strength or magnetostrictive material, the proposed method achieves significant power enhancement using directional optimization of magnetization. This method can serve as a ubiquitous autonomous energy source that converts a magnetic field into usable electrical energy in a wireless sensor network for an (Industrial) Internet of Things (IIoT). The key approach in the proposed model is to increase of the Lorentz force by vertically adjusting the magnetic flux direction of a power cable and the magnetic direction of a tip magnet. In the simulation, a 3592 times higher y-axis Lorentz force was obtained in the vertical pole array, which resulted in about a 1.6 times higher output voltage. Then, we experimentally compared the electrical output performance of six different types of pole array according to the size and direction of the tip magnet. In a one-tip magnet (10 × 10 × 10 mm3), the output power values were 2.34 mW (Vertical) and 1.23 mW (Horizontal) at 8 kΩ matching impedance. For two-tip magnets (20 × 10 × 10 mm3), the output power values of the harvester were 39.2 mW (Planar-Vertical), 18.4 mW (Orthogonal-Vertical), 8.64 mW (Planar-Horizontal), and 0.05 mW (Orthogonal-Horizontal) at 5 kΩ matching impedance. It was found that the power generation differed by 2.13 to 784 times. With this method of power enhancement using multi-disciplinary research, we successfully constructed autonomous IoT and IIoT sensor systems for smart homes, smart buildings and smart factories.

In this study, factors influencing the parking policy compliance (i.e. levying a garage option on car buyers) were identified, and then, were applied to the theory of planned behavior. To find out the influence of factors and their path, the study built a parking policy compliance model using structural equation modeling. The independent variables such as attitude, subjective norm, perceived behavioral control had positive effects on the parameter describing the efforts to secure his garage, but the parameter impact on the dependent variable was not significant. In the end, the independent variables affected the dependent variable was not significant. The perceived behavioral control utilizing regulations had positive effects on the parking policy compliance behavior, but past behavior such as street parking and prowling to find a free parking space had a negative effect on parking policy compliance behavior.

Phenolic compounds of 17.9±1.0 mg/g were extracted from Ulmus pumila with 70% ethanol. The elastase inhibitory activity related with forming wrinkle was shown an excellent wrinkle improvement effect in 70% ethanol extracts as 55.5-69.5% at phenolic concentration of 50-200 μg/ml. The tyrosinase inhibitory activity related with skin-whitening was 24% in 70% ethanol extracts at phenolic concentration of 200 μg/mL. The astringent activity of 70% ethanol extracts was shown activity of 71% at phenolic concentration of 200 μg/mL therefore it is judged that there is a high effect on pores reduction of the skin. The hyaluronidase inhibitory activity of U. pumila extracts was confirmed anti-inflammation effect of 80% at phenolic concentration of 50 μg/mL. Antimicrobial activity of U. pumila water extracts was shown each 8.7, 10.0, 11.1 and 11.8 mm clear zones on Propionebacterium acnes at phenolic concentration of 50-200 μg/ mL. The stability of the multi-functional cosmetic (lotion) added U. pumila extracts was very stable for 28 days without changing of pH and viscosity also it`s stable on temperature and sun lights. As the concentration of extracts was increased, the color of lotion was getting dark, but the sensory evaluation was high at score of 8.5.

In this study, the effect of traffic information satisfaction and expansion by the attitude on traffic information media using the structural equation modeling was evaluated. Research findings showed that the attitude formed by experience with VMS had a positive impact on user satisfaction and expansion on traffic information. Howevr, the expansion on traffic information was not affected significantly. by user satisfaction on traffic information. In other words, If experiences with VMS is positive, higher uset satisfaction on traffic information. In addition, it should be positive to expand traffic information.

A road energy harvester was designed and fabricated to convert mechanical energy from the vehicle load to electrical energy. The road energy harvester is composed of 16 piezoelectric cantilevers. We fabricated prototypes using a vehicle load transfer mechanism. Applying a vehicle load transfer mechanism rather than directly installing energy harvesters under roads decreases the area of road construction and allows more energy harvesters to be installed on the side of the road. The power generation amount with respect to the vehicular velocity change was assessed by installing the vehicle load transfer mechanism form and underground form. The energy harvester installed in the underground form generated power of 4.52 mJ at the vehicular velocity of 50 km/h. Also, power generation of the energy harvester installed in the vehicle load transfer mechanism form was 48.65 mJ at the vehicular velocity of 50 km/h.

This research is to find out the method appropriate for the forecasting of passennger demand using seasonal ARIMA model and efficient operation in Jeju National Airport. Time series monthly data for the investigation were collected ranging from January 2003 to December 2011. A total of 108 observations were used for data analysis. Research findings showed that the multiplicative seasonal ARIMA(0.1.2)(0.1.1)12 model is appropriate model. The number of passengers in Jeju National Airport will continue to rise, it was expected to surpass 20 million people.

A road energy harvester was designed and fabricated to convert mechanical energy from the vehicle load to electrical energy. The road energy harvester is composed of 24 piezoelectric cantilevers and a vehicle load transfer mechanism. Applying a vehicle load transfer mechanism rather than directly installing energy harvesters under roads decreases the area of road construction and allows more energy harvesters to be installed on the side of the road. The power generation amount with respect to the vehicular velocity change was assessed by installing the vehicle load transfer mechanism and the energy harvester in the form of speed bumps and underground. The energy harvester installed in a speed bump form generated power of 7.61 mW at the vehicular velocity of 20 km/h. Also, power generation of the energy harvester installed in the underground form was 63.9 mW at the vehicular velocity of 28 km/h. Although the number of piezoelectric cantilevers was reduced by 1/3 to 24 in comparison to the previous research results with 72 piezoelectric cantilevers, similar power generation characteristic value was obtained within the vehicular velocity of 20 km/h by altering the vehicle load transfer mechanism and cantilever vibration method.

Piezoelectric energy harvester (PEH) as a box type was fabricated in order to harvest mechanical energy imparted to roadways from passing vehicles and convert it into electricity. The PEH was composed of 72 piezoelectric cantilevers with 9 springs with elasticity stick to a bottom of the PEH. For the single piezoelectric cantilever, when a single push with approximately 5 mm displacement was incident to it, power of 0.355 mW was produced at . It is found that the power from the single piezoelectric cantilever increases when spring constant is high. We investigated power of PEH when the moving vehicle passes in it. Power was increased with increasing vehicle speed. When vehicle speed is 30 km/h, power is 20.6 mW.

In order to solve the traffic problem in jeju, we must reduce demand for car travel. In addition, demand for passenger travel by public transport policy is needed for conversion. And to improve the quality of public transport services are desperately needed. The purpose of this study, personal characteristics of the trip traveler and the relationship between transportation choice, and personal effectiveness as a factor in travel costs and travel time on the impact of transportation choices will investigate. Restructure its public transportation routes, when to switch to buses to car traffic on the data as a basis for the factors that may be. In addition to improving the quality of public transport services is expected to be able to contribute. To study the performance of the May 2010 survey was conducted. And multinominal logit model were conducted. According to the analysis, People who own homes and families with more than 5 people are likely to use cars. If a prolonged travel time is likely to use buses. However, increasing the cost of travel increases the likelihood that the car is available.

A previous study suggested that the phyto-extract mixture (PEM381) containing Camellia sinensis (leaf), Psidium guajava (leaf), and Rosa hybrida (flower) inhibited not only arachidonic acid cascade-related enzymes (5-lipoxygenase and cyclooxygenase) in vitro but also degranulation and histamine release from rat peritoneal mast cells. In this study, the same PEM381 was used to investigate its inhibitory effects on the syntheses of leukotrienes and prostaglandins as well as on serum concentration of histamine and eosinophils infiltration in type I allergic reaction-induced mice. The PEM381 could decrease concentrations of serum cysteinyl leukotrienes from mice activated by anti-DNP IgE and DNP-albumin. The concentration of serum histamine by oral administration of PEM381 (25, 50, and 100 mg/kg of body weight) in type I allergic reaction-induced mice was nM, nM, and nM, respectively, while that of positive control (promethazine hydrochloride 10 mg/kg of body weight) was nM. In addition, the PEM381 also showed inhibitory effect on the eosinophils infiltration in the nasal mucosa of mice which were sensitized with ovalbumin. However, the effect of PEM381 on the syntheses of prostaglandins seemed to be insignificant. Consequently, these results suggest that PEM381 may be useful for the prevention and treatment of type I allergy-related diseases.

In this study, we have investigated CuO doping effect on PZT-PZNN thick film for lower temperature sintering of multi-layer structure energy harvesting system. We prepared 0.69PZT-0.31PZNN powder, slurry, and green sheet to manufacture thick film ceramics with different doping amount of CuO. Various amount of CuO (0, 1, 2 and 3 mol%) were inserted into piezoelectric material composition of (Zr 0.47 Ti 0.53 )O 3- 0.31Pb {(Ni 0.6 Zn 0.4 ) 1/3 Nb 2/3 }O 3 . Laminated thick films with thickness of 0.310 mm were sintered at 900°C. Microstructures were investigated by using SEM and XRD. Also, dielectric property of sintered samples was measured by using d 33 meter. As results, dielectric permittivity increases as CuO doping amount increases, which led to decrease in resistance and increase in capacitance value. CuO doping amount of 2 mol % was found to be the optimized point with the highest d 33 value. This was explained by SEM images. The SEM images showed the increasing grain size as the CuO doping amount increase, and as the doping amount was 2 mol % or higher, secondary phase was observed in XRD. After measuring and analyzing the CuO doped samples, 2 mol% CuO doped PZT-PZNN thick film was placed on a SUS301 substrate to perform as a unimorph cantilever type energy harvesting system. First, the resonance frequency was observed in 39 Hz with 10.4V. At the resonance frequency, the impedance matching was found at the 2 M Ω, which the output power was calculated as 8 μW. This output power was then calculated as 0.267 mW/cm3.

Little is known about the prevalence of naturally acquired IgG antibodies to the capsular polysaccharides of Streptococcus pneumoniae (pneumococcal IgG) in Korea. In the present study, we investigated transplacental transfer and age-related levels of pneumococcal IgG to provide background seroepidemiologic data for S. pneumoniae in Korea. One hundred thirty eight sera were assayed by ELISA for IgG to pneumococcal polysaccharide capsular serotypes 14 and 19, the predominant serotypes for under 15 yr of age in Korea. The subjects were divided into 7 subgroups according to age. The cord/maternal geometric mean titer of pneumococcal were 4.47+/-5.88/5.21 +/- 5.88 for serotype 14, and 4.68 +/- 5.55/6.55 +/- 6.92 for serotype 1 9 (mean +/- standard deviation, microg/mL). After birth, the geometric mean titers of pneumococcal IgG for serotypes 14 and 19 expressed in microg/mL were 1.18+/-2.12 and 1.41+/-2.17 in the 0-6 months group, 0.27+/-0.19 and 0.69+/-0.93 in 7-12 months, 0.21+/-0.22 and 0.64+/-1.32 in 1-2 yr, 0.69+/-0.78 and 2.65+/-2.46 in 3-6 yr, 2.52+/-2.72 and 8.29+/-4.24 in 7-10 yr, respectively. In conclusion, reduced transplacental transfer and very low serum concentrations of pneumococcal IgG may contribute to the susceptibility of neonates, infants, and young children to S. pneumoniae infection.

In this study, composite materials were put to dry interfacial treatment by use of plasma technology. It has been presented that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. The contact angles of the samples treated under the optimum conditions and the samples that had not been treated at all were 78/spl deg/ and 72/spl deg/, respectively.