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Analysis of existing kettle and its heating system has been the topic for localization technology development. Test pieces are made, polished and etched for existing kettle analysis. Surface of test pieces is observed using SEM, the kettle is verified to be made by deep drawing process from Ferrite-Perlite material. The kettle is also identified to be plated of thickness with Nickel(16%). Also heat transfer characteristics based on hot wire arrangement is investigated and optimal hot wire system is developed. Developed control system detects overheating and stops the whole system on the long operating time. Developed kettle takes the performance evaluation test for volume expansion and satisfied for standard 'KS G3602'.

Traditional anti-reflective (AR) coating films prepared using tetraethylorthosilicate (TEOS) as a precursor absorbs water easily in addition to having a weak abrasion resistance. To improve the transmittance, hydrophobicity and abrasion resistance of AR coating film, various AR coating films were prepared using methyltrimethoxysilane (MTMS) as a precursor in addition to in- troducing a fluoroalkylsilane, acid catalyst, base catalyst and acid-base two step catalyst. The prepared AR coating films were then characterized by UV-Vis spectroscopy, contact angle analyzer, atomic force microscope (AFM), pencil scratch hardness test and cross-cut test. As a result, the transmittance of bare glass was 90.5%, while that of AR coating glass increased to 94.8% at curing temperature of 300 ℃. When the fluoroalkylsilane was added, the water contact angle of AR coating film increased from 96.3° to 108°, indicating that the hydrophobicity of the film was greatly improved. The abrasion resistance of AR coating film was also improved by the acid catalyst, whereas the transmittance increased by the base catalyst. In the case of AR coating film prepared using an acid-base two step catalyzed reaction, both the transmittance and abrasion resistance of the film was synergistically enhanced as compared with those of AR coating films prepared without introduction of a catalyst.

An overview and comparison is provided of the different emerging wireless standards and their circuit solutions, which target low data-rate IoT applications, featuring ultra-low-power and/or long-range. Different RF transceiver implementations are presented, including proprietary solutions in license-free spectrum, WLAN-based IEEE802.11ah solutions and mobile operators' alternatives based on emerging long-term evolution (LTEM) standards. The different approaches coming to the market and their circuit design aspects will be discussed.

The stress corrosion cracking (SCC) behavior of Fe18Cr10Mn1Ni(0.3–0.8)N alloys was investigated in aqueous NaCl environment by using slow strain rate test method, and the results were compared to those of Ni-free counterparts. The addition of N tended to improve the SCC resistance of Fe18Cr10Mn- and Fe18Cr10Mn1Ni-based alloys. The alloying Ni magnified the beneficial effect of N on the SCC susceptibility and, eventually, the Fe18Cr10Mn0.8N alloy was immune to SCC in 2 M NaCl solution at 50 °C. The SCC behavior of the present alloys was found to be closely related to the repassivation tendency and the resistance to pitting corrosion.

The organic Rankine Cycle (ORC) uses a kind of refrigerant as a working fluid that evaporates at relatively low temperature, as the Rankine Cycle uses superheated steam as the working fluid. A small scale ORC test bench was installed, and two different working fluids (R245fa and R134a) were injected into the test bench. The test bench was in operation with the two different working fluids under the same conditions. The effects against the system performance from the different working fluids were analysed, and root causes were identified. Other factors reflecting the power generation efficiency were also found. A conclusion was drawn, that R245fa makes the system perform better, than R134a.

In this study, a mock-up facility equipped with both BIPV windows and normal clear windows was installed to carry out the actual measurement of long-term surface temperature characteristics as the preliminary step for analyzing the impact of the surface temperature rise of thin film BIPV modules on the PV performance. The measurement was carried out for clear double windows and BIPV double windows simultaneously for each inclined angle (0°, 30°, and 90°) for one year, and various statistical analyses were carried out for the collected annual surface temperature data to investigate the surface temperature characteristics of BIPV windows. The analysis result shows that the temperature of windows applied on the vertical plane rises significantly during the winter season, and the temperature of windows applied on the horizontal plane and the inclined plane rises significantly during the summer season with high solar altitude. Regarding indoor surface temperature of windows which is closely related with the thermal comfort of indoor occupants, the surface temperature of BIPV windows with low solar heat gain coefficient was 1 °C lower than that of normal windows during the day time in summer season and was approximately 2 °C higher during the night time in winter season due to the thermal insulation effect.

The purpose of this study was to analyze the annual energy demand including heating, cooling and lighting according to kind of windows with transparent thin-film a-Si Building Integrated Photovoltaic(a-Si BIPV) for office building. The analysis results of the annual energy demand indicated that the a-si BIPV window was reduced by 8.4% than the clear gazing window. The base model A was combinate with a-Si BIPV window area of 67% and clear window area of 33% among the total exterior area. The model B is to be applied with low-e clear glass instead of clear glass of the base model A. The model B was reduced to annual energy demand of 1% more than the model A. Therefore, By using a-si BIPV solar module, the cooling energy demand can be reduced by 53%(3.4MWh) and the heating energy demand can be increase by 58%(2.4MWh) than clear glazing window in office building. Also, Model C applied to the high efficient lighting device to the model B was reduced to annual energy demand of 14.4% more than the Model D applied to the high efficient lighting device to the model A. The Model E applied with daylight dimming control system to the Model C was reduced to annual energy demand of 5.9% more than Model C.

The maximum power analysis simulator took advantage of the facilities and power consumption reduction simulator test scenario development and testing of improvement in the scenario. As a maximum demand power controller, Maximum power analysis simulator performs control and disperasion of maximum demand power by calculating base power, load forecast, and present power which are based on signal of watt-hour meter to keep the electricity under the target. In addition, various algorithms to select appropriate control methode on each of the light installations through the peak demand power is configured to management. The simulation shows the success of control power for the specified target controlled by five sequential lighting installations.

While the demand for micro-energy harvesters (μEHs) is increasing (for seamless energy source in applications such as wireless sensor node), two major problems still obstruct versatile use of them. The first problem is the self-startup capability. Because many wireless sensor nodes are likely to be located where human-maintenance is difficult, starting them up manually can be as difficult as replacing the battery. Its realization has been difficult because μEHs must be able to turn itself on without any stored energy. Some previous works have reported such a function: some needed high voltage [1] or vibration [2] and one used a transformer as a starter [3]. The other problem is the maximum power point tracking (MPPT) capability. Because it is known that MPPT algorithms usually require considerable power consumption [4], using them in μEHs is impractical. This paper suggests a new boost converter architecture and MPPT control method which can bring μEH into practical use.

The effects of shielding gas on the microstructure and localized corrosion of tube-to-tube sheet welds of SR-50A super austenitic stainless steel for seawater cooled condense were investigated in highly concentrated chloride environments. The localized corrosion resistance of the weld metal after welding with an Ar shielding gas supplemented with N 2 increased due to a decrease in the pitting resistance equivalent number (PREN) difference between the PREN IR of interdendritic region and the PREN DC of dendrite core. The localized corrosion was selectively initiated at the dendrite core because the PREN of the dendrite core was smaller than that of the interdendritic region.

The behaviors of localized corrosion associated with microstructure of tube-to-tube sheet welds of UNS S32050 super austenitic stainless steel for seawater cooled condenser were investigated in highly concentrated chloride environments. In the interdendritic region, Cr and Mo as α-stabilizers were enriched and N as the γ-stabilizer was depleted whereas in the dendrite core, Cr and Mo were depleted and N was enriched. Based on the PRENIR and PRENDC values, the localized corrosion was selectively initiated at the dendrite core (DC) because the PREN value of the dendrite core was much smaller than that of the interdendritic region (IR). It was found that the resistance to localized corrosion of the UNS S32050 SASS tube-to-tube sheet welds at least as good as that of a UNS S31254 SASS base metal with PREN 47 in highly acidified chloride environments.

5MW, open pool type research reactor, is commonly used to education and experimental purpose. It is necessary to prepare a standardization of system designs for considering a demand. HANARO has prepared the standardization of 5MW research reactor system designs based on the design, installation, commissioning and operating experiences of HANARO. For maintaining an open pool type reactor safety, a primary cooling system (after below, PCS) should remove the heat generated by the reactor under a reactor normal operation condition and a reactor shutdown condition. For removing the heat generated by the reactor, the PCS should maintain a required coolant flow rate. For a verification of the required flow rate, a flow network analysis of the PCS was carried under a normal operating condition. Based on the flow network analysis result, this paper describes the PCS flow characteristics of a 5MW open pool type research reactor. Through the result, it was confirmed that the PCS met design requirements including design flow rate without cavitation.

The power output of PV module was characterized depending on incidence angle and the azimuth using a transparent thin-film solar cell in a mock-up model at various slopes to the south, as a building integrated photovoltaic system. Simulated data was also evaluated to determine the influence of the inclined angles and the azimuth on the power performance of the PV module. The experimental and computed data fitted comparatively well through the relative error estimation after calibration. It was found that the PV module with a slope of 30°, facing south, provided the best power performance according to an annual power output, producing about 2.5 times higher power output than that with the vertical module. Furthermore, the PV module facing south showed higher power output than that to the east. The varying power output of the PV module with inclined angles can be explained by the impact of the incidence angle modifier of the glass on the PV module. Specifically, the increased inclined slope of the PV module resulted in the reduced solar energy transmission, which producing a significant reduction of power output for the PV module with a slope over 70°.

The primary purpose of this study is to examine empirically the effect of the organizational characteristics in the vessel with foreign crews on their self-efficacy and organization commitment. Currently, the restrictions on the employment of the foreign crews are being eased in the Korean shipping industry and many problems are occurring consequently. However, specific and empirical studies on the relevancy of organizational characteristics to the crew's self-efficacy and organizational commitment on board the vessels with combined crews have not yet been carried out. To solve these problems, we examined how the organizational characteristics such as communication and leadership trust of different language and culture related to vessels with combined crews influence on the self-efficacy, job satisfaction and organizational commitment of the foreign crews through SEM analysis. According to the results, hypothesis 1, 2 and 3 were all supported with statistical significance. That means that communication and leadership trust of the vessel with foreign crew had positive effects on their self-efficacy and that such self-efficacy also had a positive effect on the organizational commitment and job satisfaction. To conclude, this study suggests that foreign crew's self-efficacy should be firstly enhanced in order to improve organizational commitment on the vessel with combined crews. Furthermore, studies on self-efficacy of foreign crew's organization are urgently needed to enhance the effectiveness of an organization in a vessel with combined crews that has special environment - working environment with depression and uneasiness due to the exposure to the different language and culture, and excessive stress from the social and psychological adaptation. Therefore, an attempt of this study is considered to be timely since there has not been a study on this subject so far and result of this study will contribute a lot to the organization management of a vessel with combined crews.

This work proposes a 12b 60MS/s 0.11μm CMOS Flash-SAR ADC for wireless communication systems. The proposed Flash-SAR ADC is implemented with a 4b flash ADC and a 9b SAR ADC for high speed operation with low power consumption. Furthermore, the shared single sampling-network minimizes a sampling-time mismatch between the flash ADC and the SAR ADC, which is commonly observed in a Flash-SAR ADC without a T/H circuit. The prototype ADC occupies an active die area of 0.31mm2 and consumes 3.2mW at a 1.2V supply voltage.

This paper presents a design, a control scheme, and experiments for a new vibrating magnet robot (ViMbot). Permanent magnets in the new robot vibrate due to an external vibrating magnetic field. The vibration motion of the robot induces the locomotion of the robot. The vibratory dynamic response of the ViMbot is heavily dependent on the frequency of the vibration. This paper shows that the direction of the robot locomotion can be controlled by the vibration frequency of the external magnetic field. To achieve the distinct dynamic responses depending on the vibration frequency, three acrylic plates with different torsional stiffness are attached at three sides of the triangle-shaped ViMbot and then a magnet is attached to each plate. A strategy to find the special frequencies inducing locomotion and associated experiments with the ViMbot are presented. Control experiments for the ViMbot using the special frequencies are also presented. Because the proposed robot is actuated by an external energy source, the robot can move without traditional actuation components such as motors with batteries. This new design concept allows us to miniaturize the proposed robot.

The primary purpose of this study is to examine empirically the effect of foreign crew`s cultural and organizational characteristics on their self-efficacy and organization commitment. Currently, the restrictions on the employment of the foreign crews are being eased in the Korean shipping industry and many problems are occurring consequently. However, specific and empirical studies on the relevancy of cultural characteristics to the crew`s self-efficacy and organizational commitment on board the vessels with combined crews have not yet been carried out. To solve these problems, we examined how the cultural characteristics such as acculturation and accommodation of different culture related to the improvement of cultural homogeneity of vessels with combined crews influence on the self-efficacy, job satisfaction and organizational commitment of the foreign crews through SEM analysis. According to the results, hypothesis 1 and 2 were all supported with statistical significance. To conclude, this study suggests that foreign crew`s cultural homogeneity and their self-efficacy should be firstly enhanced in order to improve organizational commitment on the vessel with combined crews. Furthermore, a study on self-efficacy of crew organization is urgently needed to enhance the effectiveness of an organization in a vessel with combined crews that has special environment. The result of this study will contribute a lot to the organization management of a vessel with combined crews.

This paper describes the characteristics of Ru-Zr alloy gate electrodes deposited by co-sputtering. The various atomic composition was made possible by controlling sputtering power of Ru and Zr. Thermal stability was examined through 600 and 700 RTA annealing. Variation of oxide thickness and X-ray diffraction(XRD) pattern after annealing were employed to determine the reaction at interface. Low and relatively stable sheet resistances were observed for Ru-Zr alloy after annealing. Electrical properties of alloy film were measured from MOS capacitor and specific atomic composition of Zr and Ru was found to yield compatible work function for nMOS. Ru-Zr alloy was stable up to while maintaining appropriate work function and oxide thickness.

In this paper, a driving amplifier stage with 1 Watt output has been designed and fabricated, which is operating at UHF band( 470 ∼ 806 MHz) for digital TV repeater. In the driving amplifier stage, preamplifier and 1 Watt unit amplifier are integrated by one electric substrate which is 2.53 in dielectric constant and 0.8 mm thickness. When the driving amplifier stage is flown by bias voltage of 28 V DC and current of 900 mA. it has the gain of more than 53.5 dB. the gain flatness of 0.5 dB and return loss of less than -15 dB in 470 ∼ 806 MHz. Also, when two signals at 2 MHz frequency interval are input port into the driving amplifier stage with 1 Watt output, it resulted in excellent characteristics to designed specification with showing intermodulation distortion characteristics of more than 48 dBc.

Recently, various types of aircraft are flying in the sky. Especially, Unmanned Aircraft Vehicle (UAV) called drones can operate with from aerial photography to unmanned delivery thus, utilization is very high. Drones are classified as Quad, Hexa and Octa copter depending on the number of rotor. However recently, most drone has to configure and operate the number of such three rotors and two tilt-rotors. The biggest problem of these drones is a short flying time. In general, it is possible a flying about 15~20 minutes. It is highly variable depending on wind influence, nature of the communication environment. Therefore, overall flight distance is inevitably very short. And also shooting or operational area is very limited. To be presented as a solution to this problem is the swarm flight. The swarm flight has the advantage that several drones ensure flying area and execute their mission. Therefore execution of duty is possible in the wider area. In this paper in order to solve this problem, we propose effective message authentication method between aircraft that performs the swarm flight. Keywords-drone; swarm flight; authentication; message authentication

For economic evaluation of cooling plant equipment in the preliminary design stage, it is necessary to simplify energy prediction method, which should include the efficiency corrected by part-load ratio. This study proposed a simplified correlation method with regression equations of time-average partial loads and chiller capacity. DOE-2 program was used to carry out a parametric study of twelve variables. Five input variables were considered to be significant and were used in the regression equations. To test the accuracy of this method, calculated results were compared with DOE-2 simulated results. Testing showed good agreement between these two results with 5.9-7.6% error. It is hoped that this method can be used as an easy prediction tool for comparing energy use of different cooling plants during the early design stage.

The broadband high power 3-way combiner was designed and fabricated for the digital TV repeater. To achieve increase of the bandwidth and the high power capability, Wilkinson type power divider was adopted in our research. First of all, Wilkinson type power divider of equal-split and unequal-split were combined, and the characteristics of the four port in-phase power combiner was simulated for each thickness of dielectric substrates. As the results of simulation, the power combiner fabricated by using dielectric substrate of 120 mil-thickness has the characteristics as follows: insertion loss of less than -651 dB, reflection coefficient of less than -13 dB, isolation among the output ports of less than -15 dB, and pose difference among the output ports of smiler than 13. Therefore, this power combiner was possible to improve the limit of microstrip line width due to high impedance, the problem of power loss due to interaction between strip lines in a high power combiner and narrow bandwidth simultaneously. Furthermore, making broadband and high power could be achieved since the fabricated 3-way combiner has good characteristics of insertion loss, the reflection coefficient, separation between ports, and phase difference.

In this paper, the 100 watt unit ower amplifier using temperature independent biasing for DTV (Digital Television) repeater application is designed and fabricated. The DC operation point of this unit power amplifier at temperature variation from to is fixed by active bias circuit. The variation of current consumption in the 100 watt unit power amplifier has an excellent characteristics of less than 0.6A. The implemented unit power amplifier has the gain over 12dB, the gain flatness of less than 0.5dB and input and output return, loss of than 15dB over the DTV repeater frequency range (470~806MHz). This unit power amplifier yields intermodulation distortion(IMD) of more than 32dBc at 2MHz offset, which satisfies the IMD at output power of 100 watt (50dBm).

Energy harvesting is one of the key technologies used to realize self-sustaining systems such as wireless sensor networks and health-care devices. Much research on circuit design has been conducted to extract as much energy as possible from transducers, such as the thermoelectric generator (TEG) and the piezoelectric transducer (PZT). Specifically, the energy in a PZT could be extracted more efficiently by utilizing resonance as [1] and [2] demonstrated. However, the maximum output voltage swing in those techniques are limited to twice of the original swing of the PZT, and thus, had a limited energy extraction capability in spite of more energy being available from the PZT. In [3], on the other hand, the large energy is obtained with higher voltage swing, but is limited up to 247% because the load energy is used to increase the output voltage swing of PZT. To obtain far more power from PZT, we propose an alternative resonance technique through which the PZT output swing can be boosted as high as CMOS devices can sustain. This technique is applied to a dual-energy-sourced (PZT and TEG) energy-harvesting interface (EHI) as a battery charger.

A 65nm CMOS Low Drop-Out (LDO) Regulator is presented employing Gain Boost-Up and Differential Feed Forward Noise Cancellation (DFFNC) to maximize the Power Supply Rejection. The gain boost-up consists of both negative feedback and positive feedback in the error amplifier. With a 1.2V supply voltage, this LDO regulator has a 200mV drop-out voltage and the ability to handle a maximum 25mA load current. The measurement results show a −47dB PSR ratio up to 10MHz and 0.8% of load regulation for the full load current change.

The total radiated power is one of the most important factor for designing a mobile handset. Thus, in this work, a spatial loss which comes from a human hand was studied to find an effective way to reduce losses and increase the radiated power. A simple lossy object and a half-wavelength dipole antenna were used for the analysis to find a basic principle of the generation of electric fields inside a human hand. From the results, it was verified that there are internal resonance modes in which the electric field and the loss are maximized, and the resonance depends on the shape and size of a lossy object. Therefore, it must be possible to reduce the loss from a human hand by designing the handset antenna to avoid the resonant mode.

20V maximum input voltage and 1A load current hysteretic control based monolithic buck converter with phase locked loop (PLL) is presented. To achieve advantage of hysteretic control and reduce inductor current ripple with ceramic output capacitor, hysteretic based control with PLL is adopted. Furthermore, in order to decrease inductor current ripple due to wide input voltage range, switching frequency is adapted to the input supply voltage. This buck converter is fabricated with 0.35 μm high voltage BiCMOS-DMOS (BCD) process.

A Dual Hybrid Energy transfer media (DHE) Single-Inductor Boost-Inverting Flyback (SIBIF) DC-DC Converter is presented. To increase the converter efficiency, two flying capacitors as well as an inductor are adopted as additional energy transfer media. Furthermore, in order to remove the bifurcation problem occurring in the SIMO type converter, a Bifurcation Free Comparator (BFC) is adopted. The proposed chip is implemented in a 0.5-μm power BCD process and operates at 1.25 MHz with a max efficiency of 89% at an output power of 600 mW.

This paper presents a parking assistance system using visual information. The system input is an image taken by a single camera fixed to the vehicle. In the input image, we detect feature points corresponding to parking slots, among the keypoints detected by SIFT algorithm. The vehicle's location is estimated using detected feature points, and the vehicle's motion is expected using state of vehicle's wheels. Then, the system displays where the vehicle is expected to move in the parking lot based on the current location and the current wheel status. The experimental results show that the presented system can assist a driver in parking the vehicle.

A hybrid-type Single Inductor Boost/Buck Inverting Flyback(SIBBIF) DC-DC Converter is presented. To increase the converter efficiency, a flying capacitor as well as an inductor is adopted as another energy transfer medium together with multi-level gate driver (MLGD). Besides, to enhance load transient response, hybrid fast transient control (HFTC) is adopted. The proposed chip is implemented in a 0.5-µm power BCD process and operates at 1.25 MHz with a max efficiency of 87.1% at an output power of 600 mW.

Polar modulation, where a constant-amplitude phase signal is amplified by an efficient switched-mode power amplifier (PA) and an envelope signal is modulated at the drain of the PA, has been proven to improve efficiency and linearity of the PA system. However, the amplitude modulator (AM) used in such modulation systems must have wide bandwidth, low switching ripple and high efficiency. Although several AM structures have been reported the hybrid switching amplitude modulator (HSAM) shows excellent performance [1–3]. The HSAM consists of a linear amplifier as a voltage source and a switching amplifier as a dependant current source. The linear amplifier using voltage feedback defines output voltage with high frequency information in a bandwidth-expanded envelope signal and the switching amplifier using current feedback drives almost all the current to develop output voltage with the help of a current sensing circuit. If the current sensing circuit does not work well, it makes an offset to the switching amplifier and results in additional power consumption of the linear amplifier [2]. To meet a stringent spectral mask, low output impedance of the linear amplifier is needed [1]. In conclusion, wide bandwidth and low output impedance of the linear amplifier, and accurate current sensing are critical points in the design of the HSAM.

In this paper, we propose an estimation method of golf club's loci and attitudes using a 3-axis acceleration sensor1. Extraction of golf club's loci and attitudes from the 3-axis acceleration sensor is difficult. Because an output values of a 3-axis acceleration sensor are affected by gravity acceleration. For this reason, we use an appropriate golf swing model that describes relationships of golf swing properties. Based on the swing model, we estimate golf club's loci and attitudes that appropriative to the output of sensor. By applying the estimated golf club's loci and attitudes, we made a golf game. Using our estimation, we get advantages of lower cost and little constraints of location compared to other researches.

A hybrid switching amplifier for dynamic power supply applications is presented. To achieve both high speed and high efficiency, a wideband buffered linear amplifier is combined with a hysteretic controlled switching amplifier. To obtain high linearity and reduce switching loss at low power levels where the switching amplifier is not needed, the linear amplifier supplies all load current with the switching one disabled. The novel two-quadrant linear amplifier as a voltage source for regulating the output voltage has very low output impedance of about 200 m Omega around the switching frequency, a high current-driving capability of maximum 220 mA and a bandwidth wider than 7 MHz. The hybrid amplifier can drive a circuit with an equivalent impedance of 7 Omega and supply a maximum output power of 1.1 W with a maximum efficiency of about 91%. Its output voltage ranges from 0.3 V to 2.9 V for a 3.3V supply. The chip is fabricated using only thick-oxide devices in a 0.13 um CMOS process and occupies an area of 3.9 mm2.

The luminance of AMOLED displays varies depending on the temperature owing to panel degradation. In this paper, a luminance compensation method using a monitor pixel with a multiple output boost converter and DAC for digital driving scheme is introduced. This method makes the panel luminance constant irrespective of the temperature. Furthermore, it has lower power consumption compared with the previous compensation method using monitor pixel.