• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.12
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• pp.2674-2685
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• 1997

In this paper, the design and imprlementation of dual-band power amplifier which is used as a critical part for mobile phone to be simultaneously working at a dual band, 800MHz CDAM and PCS frequency band is described. DC operating point of power FET is limited to Class-B to enable long talk time considering that the tyupical power range of CDMA phones in working is around 10 to Class-B to enable long talk time considering that the typical power range of CDMA phones in working is around 10 to 15dBm, i.e., liner range. The power amplifier which employs two GaAs FETs with good linerity at a low operating point has duplexer cuplexer circuit to separate two frequency bands at input and output stage. Electromagnetic analysis for via holes and coupling between narrow transmission lines is included to design a circuit. Moduld size of 0.96CC($22{\times}14.5{\times}3mm^3$) and maximum module current of 130mA at output power range, 10 to 15dBm are attained. The power amplifer module has achieved ACPR performance with 2 to 3dB marging from IS-95 requirement at output powers, 23.5dBm for PCS and 28dBm for 800MHz CDMA respectively.

• Journal of the Korean association of regional geographers
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• v.4 no.1
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• pp.27-41
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• 1998

The communication model has been accepted as the basic research paradigm of cartography since Board(1967) discussed the map/model analogy. In that paradigm, the function of maps was limited to the media of communication, and the functionality of maps was extremely emphasized. Therefore the model could not play its own role under the new environments such as computer, GIS, scientific visualization. Nowadays, the model has been attacked on several grounds and several alternatives have been suggested. Among the objections raised are (1) geographic visualization in which maps are considered as the tool of scientific visualization, (2) the contributions of art which are ignored in the positivist cartographic research, and (3) deconstructionist arguments which deny the scientific epistemology of map as an objective form of knowledge and recognize the textuality of maps including their metaphorical and rhetorical nature. Since a publication by McCormick et al, the scientific visualization based on the powerful computer graphics is used in a wide context. Maps are treated as the tools of scientific visualization and emphasis is on exploration of the geographic data to gain understanding and insight in the geographic visualization processes. The research on geographic visualization have stayed in the early stage of developing the conceptual model and the basic visualization tools. But, it is expected that the geographic or visual thinking which is emphasized in the geographic visualization will contribute the reestablishment of links between cartography and geography. Also, the development of scientific visualization tools and strategies will offer the opportunities to suggest a fresh idea, to synthesize information and develop holistic approaches to geographical problems.

• The KIPS Transactions:PartB
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• v.13B no.2 s.105
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• pp.105-114
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• 2006

In ubiquitous environment where various kinds of computers are embedded in persons, objects and environment and they are interconnected and can be used in my place as necessary, different types of data need to be exchanged between heterogeneous machines through home network. In the environment, the efficient processing, transmission and monitoring of image data are essential technologies. We need to make research not only on traditional image processing such as spatial and visual resolution, color expression and methods of measuring image quality but also on transmission rate on home network that has a limited bandwidth. The present study proposes a new motion vector estimation algorithm for transmitting, processing and controlling image data, which is the core part of contents in home network situation and, using algorithm, implements a real time monitoring system of multi dimensional images transmitted from multiple cameras. Image data of stereo cameras to be transmitted in different environment in angle, distance, etc. are preprocessed through reduction, magnification, shift or correction, and compressed and sent using the proposed metamorphosis hierarchical motion vector estimation algorithm for the correction of motion. The proposed algorithm adopts advantages and complements disadvantages of existing motion vector estimation algorithms such as whole range search, three stage search and hierarchical search, and estimates efficiently the motion of images with high variation of brightness using an atypical small size macro block. The proposed metamorphosis hierarchical motion vector estimation algorithm and implemented image systems can be utilized in various ways in ubiquitous environment.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.578-582
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• 2009

Purpose: In extensive deep burn of the lower limb, due to less amount of soft tissue, bone is easily exposed. When it happens, natural healing or reconstruction with skin graft only is not easy. Local flap is difficult to success, because adjacent skins are burnt or skin grafted tissues. Muscle flap or free flap are also limited and has high failure rate due to deep tissue damage. The authors acquired good outcome by performing one - stage operation on bone exposed soft tissue defect with AlloDerm$^{(R)}$(LifeCell, USA), an acellular dermal matrix producted from cadaveric skin. Methods: We studied 14 bone exposed soft tissue defect patients from March 2002 to March 2009. Average age, sex, cause of burn, location of wound, duration of admission period, and postoperative complications were studied. We removed bony cortex with burring, until conforming pinpoint bone bleeding. Then rehydrated AlloDerm$^{(R)}$(25 / 1000 inches, meshed type) was applicated on wound, and thin split thickness(6 ~ 8 / 1000 inches) skin graft was done at the immediately same operative time. Results: Average age of patients was 53.6 years(25 years ~ 80 years, SD = 16.8), and 13 patients were male(male : female = 13 : 1). Flame burn was the largest number. (Flame burn 6, electric burn 3, contact burn 4, and scalding burn 1). Tibia(8) was the most affected site. (tibia 8, toe 4, malleolus 1, and metatarsal bone 1). Thin STSC with AlloDerm$^{(R)}$ took without additional surgery in 12 of 14 patients. Partial graft loss was shown on four cases. Two cases were small in size under $1{\times}1cm$, easily healed with simple dressing, and other two cases needed additional surgery. But in case of additional surgery, granulation tissue has easily formed, and simple patch graft on AlloDerm$^{(R)}$ was enough. Average duration of admission period of patients without additional surgery was 15 days(13 ~ 19 days). Conclusion: AlloDerm$^{(R)}$ and thin split thickness skin graft give us an advantage in short surgery time and less limitations in donor site than flap surgery. Postoperative scar is less than in conventional skin graft because of more firm restoration of dermal structure with AlloDerm$^{(R)}$. We propose that AlloDerm$^{(R)}$ and thin split thickness skin graft could be a solution to bone exposured soft tissue defects in extensive deep burned patients on lower extremities, especially when adjacent tissue cannot be used for flap due to extensive burn.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.566-577
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• 2009

The modification of wood color occurs rapidly during the service period at indoor. It is crucial to investigate the characteristics of color change, chemical and microscopical modification of wood at indoor. Wood products made of Japanese cedar at different years were used for this work. The tests were performed in order to evaluate the degree of color change of wood surface, breakpoint of brightness from surface to inside of wood, chemical analysis with FT-IR, and microscopical characteristics using the LM and TEM. Surface color of cedar wood stored indoor were rapidly changed at early stage, particularly ${\Delta}a$ (yellow), and ${\Delta}b$ (red) values were steeply decreased for one year old indoor wood, ${\Delta}L$ (white) value was dropped until 5 years old indoor wood compared with control sample. Decrease of peaks related to polysaccharide and lignin was noticed, especially, lignin was severely degraded. Although degradation of cell wall limited only to surface layers of indoor wood, degradation pattern of indoor wood showed similar degradation pattern to natural weathering of wood during outdoor weathering or wood behavior under artificial UV irradiation.

• The Journal of Korean Medical History
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• v.25 no.2
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• pp.155-193
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• 2012

From the part "歷代醫學姓氏(Historic Doctors)" in "醫林撮要(Uirimchualyo)", the following has been noticed and concluded. 1. Because acupuncture was originated from stony needle, the word "石(sok)" contains the meaning of needle, and from this point on, words like 石(sok), 砭石(pyumsok), 箴石(Jamsok), 鑱石(Chamsok) had been derived. 2. The word 砭石(pyumsok) used in "Hwangjenaekyong(Yellow Emperor's Canon of Medicine or Hwangdineijing)" should be interpreted as acupuncture in a verb form, not a noun form. 3. 鑱石(Chamsok) or 鑱鍼(Chamchim) was used for surgical treatment for tumor, by cutting open tumors and pressing the pus out. Therefore, 砭石(pyumsok), 鑱石(Chamsok) are the same kind of needles, and 鑱鍼(Chamchim) is the tool improved from 鑱石(Chamsok) used in the Bronze Age. 4. Kwakpak put a note on 鑱石(Chamsok) in "山海經(Sanhaekyong)" that reads "it is defined as 砥鍼(Jichim) and treats tumor." This let us know the shape of 石(sok), 砭石(pyumsok), 鑱(Chamsok), 鑱鍼(Chamchim), and the stone that can be used as a surgical tool with slim & sharp shape is obsidian. 5. Because obsidian is only found around Mt. Baekdu and limited area in South Korea & Japan in Asia, it is closely related with the life & medical environment of the tribe "Mt. Baekdu". 6. The development of 鑱鍼(Chamchim) was influenced by surgical treatment used in early stage of civilization, and its origin is traced upto Gochosun dynasty. Korea's own traditional medical knowledge is derived from this surgical treatment skill. 7. Because the acupuncture is originated from Gochosun dynasty, 鍼(chim) was derived from 箴(Jam) of 箴石(Jamsok), 䥠(Chim) & 䥠(Chim) both were used for a time being, and finally settled into 鍼(Chim). 8. The word 針(Chim) showed up at Myung dynasty, and started to be used in Korea from early Chosun dynasty. 9. In the early Chosun dynasty, 鍼(Chim) was used for medical term, and 針(Chim) for non-medical term. In the mid Chosun dynasty, 針(Chim) was used as a term for tool, and 鍼(Chim) as a term for acupunctural medical treatment. 10. Under the order of King Sunjo, Dr. Yesoo Yang published "醫林撮要(Uirimchualyo)", added "醫林撮要續集(Sequel to Uirimchualyo)", and added "歷代醫學姓氏(Historic Doctors)" again which eventually made totally 13 books of "醫林撮要(Uirimchualyo)". In addition, many parts of "醫林撮要續集(Sequel to Uirimchualyo)" were quoted in "東醫寶鑑(Donguibogam)", and influenced much in publishing "Donguibogam". 11. In "歷代醫學姓氏(Historic Doctors)" of "醫林撮要(Uirimchualyo)", the same way in "Donguibogam", referred to 針(Chim) as a term for a needle, and 鍼(Chim) as a term for Acupuncture. 12. From the usage of 針(Chim) & 鍼(Chim), shown in "鄕藥集成方(Hyangyakjipsungbang)", "醫林撮要(Uirimchualyo)" and "東醫寶鑑(Donguibogam)", we can notice the spirit of doctors who tried to take over the legitimacy of Korean tradition, and their elaboration & historical view that expresses confidence on our own medical technology, through the wording 鍼(Chim).

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.1
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• pp.105-119
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• 2015

A case study to test the open API service functions of Geographic Information Open Platform(Vworld) for Environmental Impact Assessment was carried out for improving the function of Environmental Impact Assessment Geographic Information System(EIAGIS) which is one of Environmental Impact Assessment Supporting System(EIASS) used for current Environmental Impact Assessment. Followings are the summary of the study. First, utilization of EIAGIS was low since DB renewal was limited and the quality of 2D based topographic information was low. A new service which could respond to practitioners' needs could be developed to use a open API service of Vworld provided by the Ministry of Land, Infrastructure and Transport to make up those disadvantages. EIASS with Vworld could provide a consulting service from the beginning stage of business plan and make improvements of confidence as well as fast agreements since both consultation agencies and assessment agencies are using a same program during Environmental Impact Assessment process with customized information.

• Geophysics and Geophysical Exploration
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• v.15 no.3
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• pp.136-143
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• 2012

In this case study, we present the various and consistent processing techniques for the reasonable interpretation of aeromagnetic data. In the processing stage, we especially focused on the three major respects. First, in the low latitude area, severe artifacts are occurred as a result of reduction to the pole technique. To overcome this problem, variable alternative methods were investigated. From the comparison of each technique, we concluded that energy balancing method gives more fruitful result. Second, because of limited a priori information, it is nearly impossible to employ detailed geological survey due to wide and thick spreading of soils in the survey area. So we especially investigated the new techniques such as extracting slope, curvature and aspect information mainly used in GIS field as well as conventional methods. Finally, by using the Euler deconvolution, we extracted the depth information on the magnetic anomalous body. From the synthetic analysis between depth information and previous discussed results, the detailed future survey area was proposed. We think that a series of processing techniques discussed in this study may perform an important role in the domestic and abroad resource development project as a useful guideline.

• Journal of Yeungnam Medical Science
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• v.38 no.4
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• pp.337-343
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• 2021

Background: Chromogranin A (CgA) levels have been reported to predict mortality in patients with heart failure. However, information on the prognostic value and clinical availability of CgA is limited. We compared the prognostic value of CgA to that of previously proven natriuretic peptide biomarkers in patients with acute heart failure. Methods: We retrospectively evaluated 272 patients (mean age, 68.5±15.6 years; 62.9% male) who underwent CgA test in the acute stage of heart failure hospitalization between June 2017 and June 2018. The median follow-up period was 348 days. Prognosis was assessed using the composite events of 1-year death and heart failure hospitalization. Results: In-hospital mortality rate during index admission was 7.0% (n=19). During the 1-year follow-up, a composite event rate was observed in 12.1% (n=33) of the patients. The areas under the receiver-operating characteristic curves for predicting 1-year adverse events were 0.737 and 0.697 for N-terminal pro-B-type natriuretic peptide (NT-proBNP) and CgA, respectively. During follow-up, patients with high CgA levels (>158 pmol/L) had worse outcomes than those with low CgA levels (≤158 pmol/L) (85.2% vs. 58.6%, p<0.001). When stratifying the patients into four subgroups based on CgA and NT-proBNP levels, patients with high NT-proBNP and high CgA had the worst outcome. CgA had an incremental prognostic value when added to the combination of NT-proBNP and clinically relevant risk factors. Conclusion: The prognostic power of CgA was comparable to that of NT-proBNP in patients with acute heart failure. The combination of CgA and NT-proBNP can improve prognosis prediction in these patients.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.156-169
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• 2021

Traditional morphological identification difficulties, such as phenotypic plasticity, misidentification of cryptic species, and larval stage species, can be compensated for by using DNA analysis techniques, such as DNA barcoding, in surveying zooplankton populations, including species identification. Recently, the rapid development of DNA sequencing techniques has allowed DNA-based community analysis not only for zooplankton assemblages in various aquatic ecosystems but also for the gut contents of zooplankton that are limited by conventional methods such as visual and microscopic identification. Therefore, the application of DNA sequencing can help understand biological interactions through the analysis of zooplankton food sources. The present paper introduces the major DNA-based approaches in zooplankton research topics, including taxonomic approaches by DNA barcoding, community-level approaches by metabarcoding, and gut content analyses, summarizes the analysis methods, and finally suggests the methodological topics that need to be considered for future applications.