• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.26-32
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• 2017

This paper presents a low power and high resolution incremental delta-sigma ADC that utilizes a passive integrator instead of an opamp-based active integrator. Opamp is a power-hungry block that involves tight design tradeoffs. To avoid the use of active integrator, the s-domain characteristic of an active integrator is first analyzed. Based on the analysis, an active integrator with low gain design is proposed as an alternative design method. To save power even more aggressively, a passive integrator with no static current is proposed. A 1st order single-bit incremental delta-sigma ADC using the proposed passive integrator is implemented in a 65nm CMOS process. Transistor-level simulation shows that the ADC consumes only 0.6uW under 1.2V supply while achieving SNDR of 71dB with 22kHz bandwidth. The estimated total power consumption including digital filter is 6.25uW, and resulting power efficiency is on a par with state-of-the-art A/D converters.

• Information and Communications Magazine
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• v.22 no.7
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• pp.67-80
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• 2005

In these days, international Ubiquitous Cities are being developed in many places, and their settings, aims, designs, organizations, and functionality differ among many different kinds of solutions and systems. This paper has been based on quantitative and qualitative research, and used lots of relevant data and information. Even though Ubiquitous cities are generally conceived as local information infrastructures and as a means for enhancing democratic participation, users primarily appreciate it as a tool for communication. We also observed among others, how cyberspace reproduces the dynamics of established and outsiders, which inclines us to think that virtual public is not as open as is often claimed. However, Ubiquitous cities will always offer you more comfortable life than ever from now on.

• Journal of Korean Academy of Nursing
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• v.9 no.2
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• pp.73-83
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• 1979

The objectives of this study have been conducted to establish effective clinical teaching program to I.C.U in terms of proper assignment of the clients for the students, proper rotation schedule, priorities in critical nursing problems and selection of the teaching and learning. We have analyzed statistically 1,850 patients who have been admitted during a period from January 1977 to October 31 1979 in Ewha Woman's University Hospital. The results are as follows: 1. The proportion to the total inpatients number was 6.5% and mortality rate was 16.3%. 2. The average hospitalized days were 5.8 days in I.C.U and the total death was occured from 1 st hospital day to 5th hospital day. So it shows a certain difficulties for clinical experiences of the senior students in I.C.U. 3. In the age of the death, 41.3% of the patients were in the 41-60 year age group. It shows highest mortality rate in socially active and productive age groups. 4. The mortality rates of the departments of the medicine was 18.7%, general surgery 18.5%, and neurosurgery 14.7%. 5. The number of patients admitted to the department of neurosystem was 30.6%, cardiovascular system 22.6%, respiratory system 11.1 ％ and urinary system 2.9%. 6. On utilizing instruments and machine for diagnosis and client's assessment in I.C.U, they have utilized everything a usual. But they never utilize angiogram and cardiac catheterization in cardiovascular system, and retroperitoneal pneumography in the urologic system. Further more we would recommend as follows 1. In consideration of the average hospital days and the date of death, the rotation program for clincal experience need to be adjusted as continuing practice program in apposite to current alternative practice program for comprehensive nursing care. 2. Socioeconomic needs for the patient's families and himself should be emphasized by the students in addition to physical needs. 3. Course content for critical care might be built up in considering of core disease centered nursing problems. 4. The diagnostic procedures and client's assessment items which could not experience in our university hospital by the students might be considered and refilled as filled trips to another hospital and visual aids.

• IE interfaces
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• v.22 no.2
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• pp.174-184
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• 2009

As R&D environment was changed, the research through Cyberinfrastructure emerged as a new paradigm. Advanced countries such as U.S. and U.K. invested heavily in the system for advancing R&D by building national Cyberinfrastructure. It is required to analyze how to build and utilize Cyberinfrastructure in science and technology. This paper aims to investigate and analyze the utilization status and demand of Cyberinfrastructure and to propose directions for operating it in Korea. This study is expected to be a principle foundation for decision making about developing it.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.160-163
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• 2006

Brown rice contains rice bran and germ with higher nutritional value and dietary fiber content compared with the polished rice. However, brown rice has a limitation of poor digestion. fermented brown rice could be better nutritional source and improve digestibility. Therefore, we tried to select good fermentative microorganisms which have nutritional values with high amylase and protease activities, and probiotic effects. Nineteen micro-organisms, including eight Bacillus strains isolated from Chongkukjang and 11 lactic acid bacteria, were screened for the fermentation ability and enzyme production. The liquid broths containing 2.5%(w/v) of raw brown rice powder as a sole nutritional source were used for culture media. Among the strains tested, all of the Bacillus strains and two lactic acid bacteria (Leuconostoc gelidum and Pediococcus pentosaceus) showed increase in cell population and enzyme activities. The viable cell counts of all the Bacillus strains and two lactic acid bacteria exceeded $10^7 CFU/mL$. The maximal enzyme activities produced by Bacillus sp. Bl, Bacillus sp. B2, Bacillus sp. B11, L. gelidum and P. pentosaceus were 17.85, 17.50, 17.10, 17.10 and 3.24 U/mL for amylase and 22.48, 22.04, 23.76, 12.13, and 3.4 U/mL for pretense, respectively. Therefore, the results of this study demonstrated that the above strains could be potential starters for the fermentation of raw brown rice.

• Journal of Power System Engineering
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• v.9 no.1
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• pp.76-81
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• 2005

The effect of micro-pulse plasma nitriding temperature and time on the case thickness, hardness and nitride formation in the surface of Fe-12Cr-22Mn-X alloy with 3% Co and 1% Ti alloys elements investigated. External compound layer and internal diffusion layer was constituted in plasma nitride case of Fe-12Cr-22Mn-X alloys and formed nitride phase such as ${\gamma}'-Fe4N\;and\;{\varepsilon}-Fe2-3N$. Case depth increased with increasing the plasma nitriding temperature and time. Surface hardness of nitrided Fe-12Cr-22Mn-X alloys obtained the above value of Hv 1,600 and case depth obtained the above value of $45{\mu}m$ in Fe-12Cr-22Mn-3Co alloy and $60{\mu}m$ in Fe-12Cr-22Mn-1Ti alloy. Wear-resistance increased with increasing plasma nitriding time and showing the higher value in Fe-12Cr-22Mn-1Ti alloy than Fe-12Cr-22Mn-3Co alloy.

• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.283-291
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• 2012

This study examines the optimal fractionation method and conditions for the isolation of endoprotease- and exopeptidase-active fractions from crude extracts of cuttlefish hepatopancreas (HP) using four fractionation methods: ammonium sulfate fractionation (ASF), polyethylene glycol fractionation (PGF), ion exchange chromatography (IEC), and gel filtration chromatography (GFC). Total endoprotease activity highest in the fraction II (concentrate of fractions 34-42; 842.60 U) of GFC, followed by fraction III (40-60% ammonium sulfate fraction; 670.25 U) of ASF, fraction I (concentrate of fractions 8-12; 436.89 U) of IEC, and fraction II (10-20% polyethylene glycol; 307.31 U) of PGF. Total exopeptidase activity of these fractions was highest in fraction II (2,704.70 U) of GFC, fraction III (2,110.50 U) of ASF, fraction III (1,605.60 U) of PGF, and fraction II (concentrate of fractions 38-44; 1,196.22 U) of IEC. These results showed that fraction II of GFC had the highest activity toward both exopeptidase and endoprotease, with exopeptidase activity being 3.21 times higher than of endoprotease. These results suggest cuttlefish HP could be used as a potential source for the extraction of exopeptidase, an enzyme capable of catalyzing the cleavage of N- and C-terminal amino acids in polypeptides, Like endoprotease, the most efficient method for separating exopeptide-active fractions was GFC.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.4
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• pp.231-236
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• 2019

In drug discovery or preclinical stages of development, potency parameters such as $IC_{50}$, $K_i$, or $K_d$ in vitro have been routinely used to predict the parameters of efficacious exposure (AUC, $C_{min}$, etc.) in humans. However, to our knowledge, the fundamental assumption that the potency in vitro is correlated with the efficacious concentration in vivo in humans has not been investigated extensively. Thus, the present review examined this assumption by comparing a wide range of published pharmacokinetic (PK) and potency data. If the drug potency in vitro and its in vivo effectiveness in humans are well correlated, the steady-state average unbound concentrations in humans [$C_{u_-ss.avg}=f_u{\cdot}F{\cdot}Dose/(CL{\cdot}{\tau})=f_u{\cdot}AUCss/{\tau}$] after treatment with approved dosage regimens should be higher than, or at least comparable to, the potency parameters assessed in vitro. We reviewed the ratios of $C_{u_-ss.avg}$/potency in vitro for a total of 54 drug entities (13 major therapeutic classes) using the dosage, PK, and in vitro potency reported in the published literature. For 54 drugs, the $C_{u_-ss.avg}$/in vitro potency ratios were < 1 for 38 (69%) and < 0.1 for 22 (34%) drugs. When the ratios were plotted against $f_u$ (unbound fraction), "ratio < 1" was predominant for drugs with high protein binding (90% of drugs with $f_u{\leq}5%$; i.e., 28 of 31 drugs). Thus, predicting the in vivo efficacious unbound concentrations in humans using only in vitro potency data and $f_u$ should be avoided, especially for molecules with high protein binding.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.473-480
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• 2017

We investigated the nutritional characteristics of the uncooked Skipjack tuna Katsuwonus pelamis frame (U-STF) as a basic resource for preparing flavor-enriching concentrates. The bone rate based on the fish frame (FF) was 53.2% in U-STF, thus lower than those of cooked skipjack tuna frame (C-STF), the uncooked salmon frame (U-SF), and beef leg bone (BLB). The composition of FF had 48.6-58.0% moisture, 18.4-21.3% crude protein, 7.0-15.0% crude lipid, and 12.8-22.1% ash. Compared to the proximate composition of BLB, that of FF was higher moisture and crude protein but lower solids, crude lipids, and ash. The total amino acid contents of FF was 17.6-20.8 g/100 g, which was higher than that of BLB. The levels of calcium and phosphorus of FF were 4.7-8.5 g/100 g and 2.4-4.2 g/100 g, respectively, thus lower than those of BLB. The brix concentration of FF extract was $5.0-8.2^{\circ}$, being highest in U-STF extracts, followed by extracts of U-SF and then extracts of C-STF. Our results indicate that U-STF is an optimal resource for preparing flavor-enriching concentrates.

• Journal of Acupuncture Research
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• v.33 no.4
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• pp.93-100
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• 2016

Objectives : To find an acupuncture point where more exact Surface Electromyography(SEMG) measurement can be drown, through the study of measurement of orbicularis oris. Methods : Of healthy people from 19 to 40 years of age, who did not fall under exclusion criteria (22 males and 22 females), were selected as subjects, after relaxation for 10 minutes, and they were told how to pronounce 'O' and 'U' with their lips puckered. The SEMG figures were measured with attaching disposable electrode on acupuncture point of right-and-left Hwaryo(LI19) and 1 cun away from Seungjang(CV24) on both sides when the subjects pronounced 'O' and 'U'. Results : The average value was highest on left 1 cun away from Seungjang(CV24) in pronouncing 'O' and 'U', and the average SEMG value was higher in the order of right 1 cun away from Seungjang(CV24), right Hwaryo(LI19), left Hwaryo(LI19). Average of the lower orbicularis oris is statistically higher than that of the upper orbicularis oris, which has significant meaning. However, there was no significant difference when compared by pronunciation. Average of percentage mark of differences of right-and-left measured value of each pronunciation and each acupuncture point : Pronounced 'O' and the upper part of orbicularis oris: $16.76{\pm}11.29%$, pronounced 'O' and the lower part of orbicularis oris: $22.41{\pm}12.92%$, pronounced 'U' and the upper part of orbicularis oris: $17.10{\pm}9.89%$, pronounced 'U' and the lower part of orbicularis oris : $19.20{\pm}10.82%$. Conclusion : The difference of pronunciation will not affect the results in SEMG measurement. In addition, the average of the lower orbicularis oris is statistically and significantly higher than that of the upper orbicularis oris.