• Journal of Ocean Engineering and Technology
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• v.26 no.5
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• pp.1-4
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• 2012

A energy saving device "Crown duct" has been developed and its efficiency gain has been verified experimentally in the towing tank of SSPA. The preswirl stator is well known as one of energy saving devices, which recovering the rotational energy of propeller slipstream. Crown duct has two functions of recovers the rotational energy by three blades on top of duct and of flow concentration by semi-duct. The model tests showed 4.4% efficiency gain with Crown Duct at full load condition and 6.9% at ballast condition compared with the bare hull ones for the middle class tanker.

• Journal of Korea Trade
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• v.23 no.8
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• pp.27-44
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• 2019

Purpose - The purpose of this paper is to develop a tractable general-equilibrium model of examining the impact of human resource management on intra-industry trade. Commonly, managers of Korean firms are promoted internally. It necessitates a study of human resource management and its impact on an industrial equilibrium. Design/methodology - This paper relies on theoretical analysis. We build a model in firms are hierarchical; an entrepreneur, managers, and workers. All individuals have heterogeneous managerial talents, which are the main source of managerial quality. Firms search talents for prospect managers, and eventually delegate them to supervise workers. The searching incurs a sunk cost. Findings - Our finding is as follows. Country 1, relatively abundant of managerial talents, can gain more from trade than Country 2, relatively scarce of managerial talents. This is because the higher searching cost leads to the lower survival rate of firms in Country 2. Implicatively, good jobs are destroyed, and aggregate income falls in Country 2. Originality/value - According to our study, relative abundance of managerial talents affects distribution of firm size and determines trade gain. This study can contribute to the literature of organization management and trade.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.267-274
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• 2014

Drug development and preclinical trials are challenging processes and more than 80% to 90% of drug candidates fail to gain approval from the United States Food and Drug Administration. Predictive and efficient tools are required to discover high quality targets and increase the probability of success in the process of new drug development. One such solution to the challenges faced in the development of new drugs and combination therapies is the use of low-cost and experimentally manageable in vivo animal models. Since the 1980's, scientists have been able to genetically modify the mouse genome by removing or replacing a specific gene, which has improved the identification and validation of target genes of interest. Now genetically engineered mouse models (GEMMs) are widely used and have proved to be a powerful tool in drug discovery processes. This review particularly covers recent fascinating technologies for drug discovery and preclinical trials, targeted transgenesis and RNAi mouse, including application and combination of inducible system. Improvements in technologies and the development of new GEMMs are expected to guide future applications of these models to drug discovery and preclinical trials.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.96-99
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• 2003

This paper presents the development of a Ku-band Low Noise Amplifier with the Noise figure of 1.4dBmax, the gain of 35dB, and the In/Out Return toss of -22dB/-18dB in the frequency range from 14 to 14.5GHz for Satellite transponders. All RF components were assembled using a hybrid technology with 15-mil thin-film substrates. The mechanical and thermal design of the housing was performed considering a vibration and a vacuum of space environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.3
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• pp.517-531
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• 1999

This paper presents the development of the 2-mode variable gain high power amplifier for a transmitter of INMARSAT-M operating at L-band(1626.5-1646.5 MHz). This SSPA(Solid State Power Amplifier) is amplified 42 dBm in high power mode and 36 dBm in low power mode for INMARSAT-M. The allowable error sets +1 dBm of an upper limit and -2 dBm of a lower limit, respectively. To simplify the fabrication process, the whole system is designed by two parts composed of a driving amplifier and a high power amplifier, The HP's MGA-64135 and Motorola's MRF-6401 are used for driving amplifier, and the ERICSSON's PTE-10114 and PTF-10021 are used the high power amplifier. The SSPA was fabricated by the circuits of RF, temperature compensation and 2-mode gain control circuit in aluminum housing. The gain control method was proposed by controlling the voltage for the 2-mode. In addition, It has been experimentally verified that the gain is controlled for single tone signal as well as two tone signals. The realized SSPA has 42 dB and 36 dB for small signal gain within 20 MHz bandwidth, and the VSWR of input and output port is less than 1.5:1 The minimum value of the 1 dB compression point gets 5 dBm for 2-mode variable gain high power amplifier. A typical two tone intermodulation point has 32.5 dBc maximum which is single carrier backed off 3 dB from 1 dB compression point. The maximum output power of 43 dBm was achieved at the 1636.5 MHz. These results reveal a high power of 20 Watt, which was the design target.the design target.

• Journal of Technology Innovation
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• v.13 no.3
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• pp.131-151
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• 2005

Industrial Technology Development Program enables the recipient to set up technology infrastructure and to facilitate technology diffusion. In return, government charges royalty from the program recipient. However, the current royalty system is not in the effective form. This study analyzes the various aspects of royalty collection methods applied to the Industrial Technology Development Program and recommend the following: (1) employ the combination of fixed amount royalty and running royalty with predetermined portion of revenue generated, (2) adjust the royalty collection duration by applying product life cycle, and (3) devise new program to link extra-gain from royalty collection with commercialization and other means to increase the effectiveness of research and development activities.

• Journal of Positioning, Navigation, and Timing
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• v.9 no.4
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• pp.367-378
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• 2020

This paper introduces the development of the iterative multiple signal classification (MUSIC)-based direction-of-arrival (DOA) estimation system using a rotator that can control the direction of antenna for the global navigation satellite system (GNSS) interference. The system calculates the spatial spectrum according to the noise eigenvector of all dimensions to measure the number of signals (NOS). Also, to detect the false peak, the system adjusts the array antenna's direction and checks the change's peak angles. The phase delay and gain correction values for system calibration are calculated in consideration of the chamber's structure and the characteristics of radio waves. The developed system estimated DOAs of interferences located about 1km away. The field test results show that the developed system can estimate the DOA without NOS information and detect the false peak even though the inter-element spacing is longer than the half-wavelength of the interference.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.452-458
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• 2020

In this paper, the contents of the development of RESS(Radar Environmental Signals Simulator) for the test of active phased array multi-function radar are described. The developed RESS can simulate multiple target environments, such as target/jamming/missile response/cluster signals, by using received radar operational information and simulated scenario. It can also modulate frequency, phase, gain, timing on all waveforms operated by multi-function radar and simulated two targets and one jamming in the beam. The RESS can be used to perform functional and performance verification of the active phased array multi-function radar with sub-array receiving structures.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.3
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• pp.369-375
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• 2017

One of good DF(Direction Finding) methods is based on TDOA(Time Difference of Arrival) estimation when finding underwater moving target. For small DF error, high time resolution A/D(Analog-to-digital) conversion board and long baseline are needed. But the result of sea trial about close-range and high speed moving target, spatial correlation coefficient and appeared poor properties below 0.3 when hydrophone arrangement are separated over 6 ${\lambda}$ because of underwater fading channel. And we also find out that the distance between hydrophone should be under 4 ${\lambda}$ apart to take advantage of spatial correlation coefficient gain and performance of DF in underwater moving channel environments.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.2
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• pp.162-169
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• 2019

This paper describes a thermal image processing algorithm for uncooled type TEC-less IR detector which is applicable to fire control system of small arms. We implemented a real-time gain and offset compensation algorithm based on polynomial approximation from the raw dataset which is acquired by two reference temperature of blackbody from various FPA(Focal Plane Array) temperature. Through the experiment, we analyzed the output characteristics of detector's raw-data and compared IR image quality to traditional non-uniformity correction method. It shows that the proposed method works well in all FPA temperature range with low residual non-uniformity.