• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.238-238
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• 2015

There are demands for water environmental analysis of discharge processes in paddy fields, however, it is not fully understood in nutrients discharge process for watershed modeling. As hydrological processes both surface and ground water and agricultural water managements are so complex in paddy fields, the development of lowland paddy fields watershed model is more difficult than upland watershed model. In this research, the improvement of SWAT (Soil and Water Assessment Tool) model for a paddy watershed was conducted. First, modification of surface inundated process was developed in improved pot hole option. Those modification was evaluated by monitoring data. Second, the monitoring data in river and drainage channel in lowland paddy fields from 2012 to 2014 were analyzed to understand discharge characteristics. As a case study, Imbanuma basin, Japan, was chosen as typical land and water use in Asian countries. In this basin, lowland paddy fields are irrigated from river water using small pumps that were located in distribution within the watershed. Daily hydrological fluctuation was too complex to estimate. Then, to understand surface and ground water discharge characteristics in irrigation (Apr-Aug) and non-irrigation (Sep-Mar) period, the water and material balance analysis was conducted. The analysis was composed two parts, watershed and river channel blocks. As results of model simulation, output was satisfactory in NSE, but uncertainty was large. It would be coming from discharge process in return water. The river water and ground water in paddy fields were exchanged each other in 5.7% and 10.8% to river discharge in irrigation and non-irrigation periods, respectively. Through this exchange, nutrient loads were exchanged between river and paddy fields components. It suggested that discharge from paddy fields was not only responded to rainfall but dynamically related with river water table. In general, hydrological models is assumed that a discharge process is one way from watershed to river. However, in lowland paddy fields, discharge process is dynamically changed. This function of paddy fields showed that flood was mitigated and temporally held as storage in ground water. Then, it showed that water quality was changed in mitigated function in the water exchange process in lowland paddy fields. In future, it was expected that hydrological models for lowland paddy fields would be developed with this mitigation function.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.4
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• pp.7-11
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• 2013

As thermosonic ball bonding is developed for more and more advanced applications in the electronic packaging industry, the control of process stresses induced on the integrated circuits becomes more important. If Cu bonding wire is used instead of Au wire, larger ultrasonic levels are common during bonding. For advanced microchips the use of Cu based wire is risky because the ultrasonic stresses can cause chip damage. This risk needs to be managed by e.g. the use of ultrasound during the impact stage of the ball on the pad ("pre-bleed") as it can reduce the strain hardening effect, which leads to a softer deformed ball that can be bonded with less ultrasound. To find the best profiles of ultrasound during impact, a numerical model is reported for ultrasonic bonding with capillary dynamics combined with a geometrical model describing ball deformation based on volume conservation and stress balance. This leads to an efficient procedure of ball bond modelling bypassing plasticity and contact pairs. The ultrasonic force and average stress at the bond zone are extracted from the numerical experiments for a $50{\mu}m$ diameter free air ball deformed by a capillary with a hole diameter of $35{\mu}m$ at the tip, a chamfer diameter of $51{\mu}m$, a chamfer angle of $90^{\circ}$, and a face angle of $1^{\circ}$. An upper limit of the ultrasonic amplitude during impact is derived below which the ultrasonic shear stress at the interface is not higher than 120 MPa, which can be recommended for low stress bonding.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.1
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• pp.171-187
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• 2016

The study performed a comparison analysis of market brand patterns for slim-fit dress shirts and analyzed the body surface development figure of men in their 40s using 3D body scan data and developed slim-fit dress shirt patterns suitable for middle-aged men. The sizes of slim-fit dress shirt patterns showed a slight difference depending on brand. The overlap map of slim-fit dress shirt patterns for brands demonstrates how difference of one-dimensional sizes reflect on two-dimensional patterns. This map provides useful information for pattern design and allows and easy recognition of pattern size differences. A try-on system evaluation through 3D-Simulation allows a grasp of the fitness of neckline and size tolerance of under the arms in front, the silhouette of side lines, and overall fitness in front that also allows analysis of the front/back balance of a shirt in side, the size tolerance proportion in front/back, and the fitness of the arm-hole line. Thus, we obtained try-on results that were equivalent to wearing actual clothing. According to the drafting size suggested in the developed final pattern, the total width was 'C/2+5.5cm', and the front was set at 1cm bigger in the size difference of the front and back. The width of the front neck and the back neck was set identically at 'C/12', while the width of the front neck was set to 'C/12+1.5cm'. For the armhole depth, we added 'C/4+2cm', and '0.5cm and 1.5cm' for the width of the front and back to anthropometry. The results of the try-on evaluation through 3D-Simulation indicated that the fitness of the final slim-fit dress shirt pattern was superior to available slim-fit dress shirt patterns on the market and evaluated as superior to the types for middle-aged men.

• Journal of the Korean Geographical Society
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• v.42 no.3 s.120
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• pp.315-331
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• 2007

Some reverse fault lines are passing through the alluvial fans and west hill slope of Bulguksa mountains including Mt. Toham in the directions of N-S and NW-SE. The study area is known as relatively unstable, because of active faults. Assuming on the record of Samguksagi about earthquakes, the architects in the construction of the Bulguksa Temple should have recognized the possibility of breakdown from the earthquakes and the need for an unique structure against at that time. Against earthquakes, Grengee technique, a stonework construction technique following wooden one and use of Chuduseok(Dongtleseok or Chumchaseok) were applied for the construction of the Bulguksa Temple. By designing the foundation stone with hole, a structure is prevented from modification that pillars secede from a foundation stone in spite of horizontal load of earthquake while wood construction is strong frame at earthquake. The Bulguksa Temple is usually evaluated to be a beautiful architecture from the appearances like the weight balanced structure with unique decoration. Impressive architectures are beautiful in balance and harmony coming from the important and specific rolls in its own way by each part of whole structure. This beauty comes from the science.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.10
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• pp.1005-1016
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• 2002

In this paper, a 2 GHz tapered shape of multiport power divider/combiner modified from the model published by [10] and adopted PBG(Photonic Band Gap) structure is proposed. Parameters determining electrical property of the circuit structure have been analyzed by HFSS simulation. For input matching, balance of output signals and phase linearity at each output port, one circular hole has been etched out on the circuit surface. 1:2 and 1:3 power dividers/combiners designed by this study have been compared with the same circuits designed by the method of [10] in terms of S-parameters. As a result, it has been found that tile modified structure and PBG of power divider/combiner have improved return loss more than 20 dB and another 18 dB. respectively, at 2 GHz.

• Journal of Advanced Navigation Technology
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• v.6 no.4
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• pp.279-290
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• 2002

In this paper, tapered shape of multiport power divider/combiner modified for 2 GHz range from the model published by [10] is proposed. Parameters determining electrical property of the circuit structure have been analyzed by HFSS simulation. For input matching, balance of output signals and phase linearity at each output port, one circular hole has been etched out on the circuit surface. 1:2 and 1:3 power dividers/combiners designed by this study have been compared with the same circuits designed by the method of [10] in terms of S-parameters. As a result, it has been found that the modified structure of power divider/combiner have improved return loss more than 20 dB and another 18 dB, respectively, at 2 GHz.

• World Technopolis Review
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• v.1 no.4
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• pp.276-286
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• 2013

"Federal investments into the future of a region" - pushing economy in the right direction or throwing tax money into a black hole? Hot-headed contentions keep circulating within politics and economy discussing the effect of technology centers and their sustainability within a region. Start-up support and technological infrastructure with the auxiliary service of well developed sector-oriented clusters as a fertile soil for successful networks are an undeniable advantage of well organised technology centers. Sceptic contemporaries still hold against that in order to implement such a center millions of federal funds for infrastructure and operation are invested. What output of this tax money is verifiable in the long run? The case of Dortmund provides substantial food for this necessary and relevant discussion. Now, after 27 years of history of the TechnologieZentrumDortmund, TZDO for short, a positive balance can be drawn. This is not just a matter of personal belief and stance. Fortunately, a recent study on the economic effects of the TZDO on the whole region was performed by the Center of Applied Economy Research M$\ddot{u}$nster, Germany (Gundel and Luttmann 2008). The result is clear and measurable: the TZDO has shown to be of great impact on the positive development of a whole region. This paper presents an account of the approach of the TechnologieZentrumDortmund and its current strategy and mode of operation to reach an utmost of effectiveness of personal and pecuniary input in establishing economic success for the region of Dortmund. An immense change of minds, employment opportunities and a massive structural change of the whole region were some of the ambitious aims that had to be reached and that are achieved to a large extent.

• Smart Structures and Systems
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• v.2 no.2
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• pp.115-126
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• 2006

The Terra-Scope system is an affordable 4-D down-hole seismic monitoring system based on independent, microprocessor-controlled sensor Pods. The Pods are nominally 50 mm in diameter, and about 120 mm long. They are expected to cost approximately $6000 each. An internal 16-bit, extremely low power MCU controls all aspects of instrumentation, eight programmable gain amplifiers, and local signal storage. Each Pod measures 3-D acceleration, tilt, azimuth, temperature, and other parametric variables such as pore water pressure and pH. Each Pod communicates over a standard digital bus (RS-485) through a completely web-based GUI interface, and has a power consumption of less than 400 mW. Three-dimensional acceleration is measured by pure digital force-balance MEMS-based accelerometers. These accelerometers have a dynamic range of more than 115 dB and a frequency response from DC to 1000 Hz with a noise floor of less than $30ng_{rms}/{\surd}Hz$. Accelerations above 0.2 g are measured by a second set of MEMS-based accelerometers, giving a full 160 dB dynamic range. This paper describes the system design and the cooperative shared-time scheduler implemented for this project. Restraints accounted for include multiple data streams, integration of multiple free agents, interaction with the asynchronous world, and hardened time stamping of accelerometer data. The prototype of the device is currently undergoing evaluation. The first array will be installed in the spring of 2006.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.2
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• pp.81-89
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• 2019

In this study, wind tunnel test on Quad-Tilt Propeller which has tandem wings is carried out to analyze the aerodynamic interference effect of front wing and propeller on rear wing during forward flight. Using 6-axis balance system, forces and moments of whole aircraft were measured and using strain gauge at wing root, bending moments were measured to observe change of aerodynamic force of each wings. A 12-hole probe was used to measure the flow field in the wing and propeller wake. Flow characteristics were observed qualitatively through flow visualization experiment using tuft and smoke. To measure the aerodynamic interference by elements, the influence of front wing and propeller on rear wing was analyzed by changing the wings and propellers mount combination.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.9 s.112
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• pp.811-820
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• 2006

Ultra wideband CPW batons are proposed in this paper. The proposed talons are consisted of ultra wideband multi-stage Wilkinson dividers and 'X'-shaped $180^{\circ}$ out-of-phase generator. Bottom-bridges and via-holes are used to connect CPW ground lines instead of the conventional air-bridges which require troublesome manual working in fabrication with HMIC(Hybrid Microwave Integrated Circuits) substrates. The proposed CPW batons have ultra wideband of 3 or $10(=F_{figh}/F_{low})$ theoretically, the wideband characteristics and S-parameters of the basis Wilkinson divider are directly converted to those of the proposed batons. The proposed batons are so compact and small compared to the conventional Wilkinson batons because no additional area for out-of-phase section is required. So the size of the proposed batons is exactly the same as that of the basis Wilkinson dividers. As examples, 3-stage and 7-stage wideband Wilkinson dividers are converted to the proposed batons. Their measured operating bandwidth are $1\sim3GHz$ and $0.8\sim5GHz$, respectively, with excellent matching, isolation and power division performances. The measured magnitude and phase balance errors are ${\pm}0.5dB\;and\;0.45\;dB,\;and\;{\pm}5^{\circ}\;and\;{\pm}10^{\circ}C$ over $1\sim3GHz\;and\;0.8\sim5GHz$, respectively.