• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.217-232
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• 2021

This study calculated the productivity and cost of extraction and processing of logging residues by cut-to-length (CTL) and whole-tree (WT) harvesting methods. In addition, the comparative analysis of the characteristics of wood chip fuel to examine whether it was suitable for the fuel conditions of the energy facility. In the harvesting and processing system to produce the wood chips of logging residues the system productivity and cost of the CTL harvesting system were 1.6 Gwt/SMH and 89,865 won/Gwt, respectively. The productivity and cost of the WT harvesting system were 2.9 Gwt/SMH and 72,974 won/Gwt, respectively. The WT harvesting productivity increased 1.3times while harvesting cost decreased by 18.7% compared to the CTL harvesting system. The logging residues of wood chips were not suitable for CTL wood chips based on International Organization for Standardization (ISO 17225-4:2021) and South Korea standard (NIFoS, 2020), but the quality (A2, Second class) was improved through screening operation. The WT-unscreened wood chips conformed to NIFoS standard (second class) and did not conform to ISO but were improved through screening operation (Second class). In addition to the energy facility in plant A, all wood chips except CTL-unscreened wood chips were available through drying processing. The WT-unscreened wood chips were the lowest at 99,408 won/Gwt. Plants B, C, and D had higher moisture content than plant A, so WT-unscreened wood chips without drying processing were the lowest at 57,204 won/Gwt. Therefore, the production of logging residues should improve with operation methods that improve the quality of wood chips required for applying the variable biomass and energy facility.

• Journal of the Korea Society of Computer and Information
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• v.19 no.4
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• pp.1-8
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• 2014

As cores in multi-core processors are integrated in a single chip, power density increased considerably, resulting in high temperature. For this reason, many research groups have focused on the techniques to solve thermal problems. In general, the approaches using mechanical cooling system or DTM(Dynamic Thermal Management) have been used to reduce the temperature in the microprocessors. However, existing approaches cannot solve thermal problems due to high cost and performance degradation. However, floorplan scheme does not require extra cooling cost and performance degradation. In this paper, we propose the diverse floorplan schemes in order to alleviate the thermal problem caused by the hottest unit in multi-core processors. Simulation results show that the peak temperature can be reduced efficiently when the hottest unit is located near to L2 cache. Compared to baseline floorplan, the peak temperature of core-central and core-edge are decreased by $8.04^{\circ}C$, $8.05^{\circ}C$ on average, respectively.

• Korean Journal of Optics and Photonics
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• v.31 no.5
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• pp.213-217
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• 2020

In this study we report a wet-etching-based fabrication method for adiabatic optical-fiber tapers (OFTs), and describe their adiabaticity and HE₁₁ mode evolution at a wavelength of 1550 nm. The profile of the fabricated system satisfies the adiabaticity properties well, and the far-field pattern from the etched OFT shows that the fundamental HE₁₁ mode is maintained without a higher-order mode coupling throughout the tapers. In addition, the measured far-field pattern agrees well with the simulated result. The proposed adiabatic OFTs can be applied to a number of photonic applications, especially fiber-chip packages. Based on the fabricated adiabatic OFT structures, the optical transmission to the inversely tapered silicon waveguide shows large spatial-dimensional tolerances for 1 dB excess loss of ~60 ㎛ (silicon waveguide angle of 1°) and insertion loss of less than 0.4 dB (silicon waveguide angle of 4°), from the numerical simulation. The proposed adiabatic coupler shows the ultrabroadband coupling efficiency over the O- and C-bands.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.9
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• pp.699-708
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• 2006

Bus splitting technique reduces bus energy by placing modules with frequent communications closely and using necessary bus segments in communications. But, previous bus splitting techniques can not be used in MPSoC platform, because it uses cache coherency protocol and all processors should be able to see the bus transactions. In this paper, we propose a bus splitting technique for MPSoC platform to reduce bus energy. The proposed technique divides a bus into several bus segments, some for private memory and others for shared memory. So, it minimizes the bus energy consumed in private memory accesses without producing cache coherency problem. We also propose a task allocation technique considering cache coherency protocol. It allocates tasks into processors according to the numbers of bus transactions and cache coherence protocol, and reduces the bus energy consumption during shared memory references. The experimental results from simulations say the bus splitting technique reduces maximal 83% of the bus energy consumption by private memory accesses. Also they show the task allocation technique reduces maximal 30% of bus energy consumed in shared memory references. We can expect the bus splitting technique and the task allocation technique can be used in multiprocessor platforms to reduce bus energy without interference with cache coherency protocol.

• KSBB Journal
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• v.22 no.6
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• pp.371-377
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• 2007

Polyhydroxyalkanoates (PHAs) are a family of microbial polyesters that can be produced by fermentation from renewable resources. PHAs can be used as completely biodegradable plastics or elastomers. In this paper, novel applications of PHAs in biosensor are described. A general platform technology was developed by using the substrate binding domain (SBD) of PHA depolymerase as a fusion partner to immobilize proteins of interest on PHA surface. It could be shown that the proteins fused to the SBD of PHA depolymerase could be specifically immobilized onto PHA film, PHA microbead, and microcontact printed PHA surface. We review the results obtained for monitoring the specific interaction between the SBO and PHA by using enhanced green fluorescent protein, red fluorescent protein, single chain antibody against hepatitis B virus preS2 surface protein and severe acute respiratory syndrome coronavirus surface antigen as model proteins. Thus, this system can be efficiently used for studying protein-protein and possibly protein-biomolecule interactions for various biotechnological applications.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.235-242
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• 2010

Emotion science is one of the rapidly expanding engineering/scientific disciplines which has a major impact on human society. Such growing interests in emotion science and engineering owe the recent trend that various academic fields are being merged. In this paper we review the recent techniques in the measuring the emotion related elements and applications which include animal model system to investigate the neural network and behaviour, artificial nose/neuronal chip for in-depth understanding of sensing the outer stimuli, metabolic controlling using emotional stimulant such as sounds. In particular, microfabrication techniques made it possible to construct nano/micron scale sensing parts/chips to accommodate the olfactory cells and neuron cells and gave us a new opportunities to investigate the emotion precisely. Recent developments in the measurement techniques will be able to help combine the social sciences and natural sciences, and consequently expand the scope of studies.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.2
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• pp.93-100
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• 2009

This paper presents a step up four channel DC-DC converter using charge pump voltage doubler structure. Our goal is to design and implement DC-DC converter for capacitive SP4T RF MEMS switch in front end module in wireless transceiver system. Charge pump structure is small and consume low power 3.3V input voltage is boosted by DC-DC Converter to $11.3{\pm}0.1V$, $12.4{\pm}0.1V$, $14.1{\pm}0.2V$ output voltage With 10MHz switching frequency. By using voltage level shifter structure, output of DC-DC converter is selected by 3.3V four channel selection signals and transferred to capacitive MEMS devices. External passive devices are not used for driving DC-DC converter. The total chip area is $2.8{\times}2.1mm^2$ including pads and the power consumption is 7.52mW, 7.82mW, 8.61mW.

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.237-242
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• 2006

Nowadays, LEDs has been applied to the luminescent devices of various fields because of the invention of high efficient blue chip. Recently, especially, the white LEDs composed of InGaN blue chips and a yellow phosphor (YAG:Ce3+) have been investigated extensively. With the exception of YAG:Ce3+ phosphor, however, there are no reports on yellow phosphor that has significant emission in the 450~470 nm excitation range and this LED system is the rather low color rendering index due to their using two wavelength. Hence, we have attempted to synthesize thiogallate phosphors that efficiently under the long wavelength excitation range in the present case. Among those phosphors, we have synthesized Sr2Ga2S5:Eu2+ phosphor by change the host material of SrGa2S4:Eu2+ which is well known phosphor and we investigated the luminescent properties. In order to obtain the harmlessness and simplification of the synthesis process, sulfide materials and mixture gas of 5 % H2/95 % N2 were used instead of the CS2 or H2S gas. The prepared phosphor shows the yellow color peaking at the 550 nm wavelength and it possible to emit efficiently under the broad excitation band in the range of 300~500 nm. And this phosphor shows high luminescent intensity more than 110 % in comparison with commercial YAG:Ce3+ phosphor and it can be applied for UV LED due to excitation property in UV region.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.95-104
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• 2004

This paper propose a motion estimator architecture to reduce the power consumption of the most-power-consuming motion estimation method when designing multimedia SoC with deep submicron technologies below 0.13${\mu}{\textrm}{m}$. The proposed architecture considers both dynamic and static power consumption so that it is suitable for large leakage process technologies, while conventional architectures consider only dynamic power consumption. Consequently, it is suitable for mobile information terminals such as mobile videophone where efficient power management is essential. It exploits full search method for simple hardware implementation. It also exploits early break-off method to reduce dynamic power consumption. To reduce static power consumption, megablock shutdown method considering power line noise is also employed. To evaluate the proposed architecture when applied multimedia SoC, system-level control flow and low-power control algorithm are developed and the power consumption was calculated based on thor From the simulation results, power consumption was reduced to about 60%. Considering the line width reduction and increased leakage current due to heat dissipation in chip core, the proposed architecture shows steady power reduction while it goes worse in conventional architectures.

• Journal of Korean Medical classics
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• v.6
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• pp.89-130
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• 1993

Huh-joon's medical thoughts shown on his medical book of the Doog-Eui-Bo-Kham can be summerized as follows. 1. The general trend of medical science in Koryo dynasty is that much more interests were concentrated upon the books about curative means rather than upon the books about theoretical knowledge of medical science. With the development of Hyang Yak(鄕樂) (the term referring either various kinds of domestic medical stuffs such as herbs or the curative methods using those stuffs) and the writing of books on Hyang Yak, independent medical science of the nation's own was established in late Koryo dynasty. And the national medical science was continuously further developed until early Choson dynasty. Briskly-expanded mutual exchanges with China in early Choson dynasty provided Choson opportunities to import Chinese medical science and to examine it. Under this circumstances, he wrote the Dong-Eui-Bo-Kham. 2. As we look over the preface and Chip-Rae-Muo(集例文), we can find the characterstic of Doog-Eui-Bo-Kham is that the philosophical theory of Taoism was quoted in explaining the principles of his medical science and that the main idea of Naekyuog is the basis in explaining the way of curing diseases. 3. 83 kinds of medical books were quoted in the Doog-Eui-Bo-Kham. Besides, as many as 200 kinds of books including Tao-tzu's teaching books(道書), history books(史書), almanac(曆書), and Confucius' teaching books(儒家書籍) were quoted in total. Naekyuog and Eue-Hak-Ip-Mun, Dan-Kye-Sim-Bup were the most frequently quoted books among them. 4. Huh-Joon's medical thoughts about health care were like these. 1) The reason why Huh-Joon regarded the idea of health care as of great importance was that he laid much more emphasises on the preventive medicines rather than on the remedial medicines. The direct reason was that he was greatly influenced by profound knowledge of Taoist's study of discipline and who participated in the editing the books from the beginning. 2) Huh-Joon's outlook on human body started from the theory of "Unity of Heaven and Man"(天人合一論), which implied man was a kind of miniature universe. In addition to that, he largely theory of essence(精), vital force(氣), and spirit(神) which were regarded very important as the three most valuable properties in Taoism. However, he took his medical ground on practical and pragmatic idea that he did not discuss fundamental essence(元精), fundamental vital force(元氣), and fundamental spirit(元神) which were given by Heaven from the received only the theory of essence, vital force, and spirit which were acquired after birth and worked mainly on realistic activity of life. 3) Huh-loon accepted Do-In-Bup(導引法) sharply as a method to prevent and cure diseases. 5. Huh-loon's medical thoughts on remedial aspects are as 1) Naekyung was considered so important in Dong-Eui-Bo-Kham that not only each paragraph was begun with the Quotations from Nackyung but also the edited order of the content of the book the same with that of Naekyung. And differently from the former korean medical books he accepted at large and recorded the theories of the four noted physicians of the Geum-Won era(金元四大家) by Dong-Eui-Bo-Kham. 2) For the first time, Huh-Joon introduced the theory of Un-Ki (運氣論) in the Dong-Eui-Bo-Kahm. However, he accepted it as a pathological function of human body but he did not apply physical constitution, physiological function, pathological function, and remedial methods. 3) Huh-loon liked to use Hyang Yak that he recorded korean name of Hyang Yak(鄕名), places of the production(産地), the time of collecting(採取時月), and the way of drying herbs(陰陽乾正法) in the remedial method of a single medicine prescription for diseases at the end of each paragraph. By doing so, he developed, arranged, and revived Hyang Yak. 4) He believed that since the natural features of China were different from those of Korea the reasons of being attacked with its remedial methods couldn't be the same with different from Chinese medical books which primarily focused on paralysis and the injury of the cold has his own structure in his book that he founded independent science of this nation. He consulted enormous documents He discovered and wrote the theory and therefore concrete methods for diseases so that the book hadthe principles of outbreak of diseases(理), methods of cure(法), prescription(方), and a single medicine prescription(藥) and set system of medical science in a good order. By doing so, he and pragmatic development of medical science.