• Sleep Medicine and Psychophysiology
• /
• 제1권1호
• /
• pp.47-59
• /
• 1994

Objectives: The main purpose of this study was to investigate the possible differences in sleepiness, performance, and body temperature during the night between morning(M) and evening(E) type subjects. Methods: After a survey study, to verify the validity and reliability of the Korean translation of the Home' and $\ddot{O}stberg's$ Morningness-Eveningness Questionnaire(1976), 8 extreme M-type subjects(3males, 5 females) and 8 extreme E-type subjects(3 males, 5 females) were selected from the university student population who had participated in the survey study. All subjects underwent sleep latency test and a battery of performance tests at intervals of 2 hours through the night, from 23:00 to 07:00. Oral temperature of each subject was taken every hour from 21 : 00 to 8 : 00. Between the testing times, the experimenters ensured that subjects remained awake. Results: More profound sleepiness was found in the M-type compared to the E-type throughout the night, with significant differences in sleepiness occuring at 23:00 and 01:00 hours. Overall performance efficiency tended to be lower through, the night in the M-type than in the E-type on all tests. A difference in time of temperature minimum between the two types was not noteworthy. Rather, there appeared to be a substantial difference in temperature level during the declining phase, with the temperature of the M-type being lower than that of the E-type. Conclusions: These results indicate the existance of a temporal relationship between sleepiness, perfonnance and body temperature during night work. Since the M-type exhibited greater sleepiness and lower performance efficiency overnight than the E-type, it may be assumed that the E-type is more suitable for and tolerable to night work. There was some discussion of the limitations in generalizing these results together with some suggestions for future studies.

• Korean Journal of Construction Engineering and Management
• /
• 제14권1호
• /
• pp.52-62
• /
• 2013

Owners' efforts to acquire Green building certification, which started in 2002, have been rapidly increasing since 2006. The causes of the increased owners' interests are due to various incentives, legal obligation, and purpose of advertising. As project owners generally are deficient in capabilities and knowledge on how to deal with administrative works on certification, they tend to fulfill the minimum requirements for certification. However, effective administration process need capabilities of identifying individual making decision point and review information. The implementation of green building certification system is expected to provide comfort to both occupants and potential users. Furthermore it contributes to reducing energy costs throughout the phase of O&M. In addition, technology innovation in green industry can be obtained. Therefore, this study is intended to support owners in order that they can clarify certification tasks and make a rational decision-making in time. For this purpose, first of all, the major decision points were selected as the gateways of green building certification process. And then management system based on IDEF3 modeling was developed for supporting owners' decision-making performance. This management system will improve owners' overall capacity in handling all the tasks regarding the certification of Green building.

• Applied Chemistry for Engineering
• /
• 제26권6호
• /
• pp.719-724
• /
• 2015

Isoliquiritigenin (ILG) is a hydrophobic component in licorice and has a variety of pharmaceutical and biological activities. In this study, we prepared an isoliquiritigenin-hydroxypropyl-${\beta}$-cyclodextrin (ILG/HP-${\beta}$-CD) complex by freeze-drying method to enhance its water solubility. The complex was characterized by phase solubility studies, DSC, SEM, and 1H NMR. Antimicrobial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were evaluated by broth dilution method. The results showed that the stoichiometry of ILG/HP-${\beta}$-CD complex was 1 : 1. The antimicrobial activity of ILG/HP-${\beta}$-CD complex was higher than that of using free ILG against S. aureus and E. coli. Therefore, we suggest that ILG/HP-${\beta}$-CD complex may be used as a natural antiseptic and could potentially replace synthetic preservatives in cosmetic and food industries.

• Journal of Korea Spatial Information System Society
• /
• 제4권2호
• /
• pp.5-22
• /
• 2002

The considerable budgets for the 2nd-phase NGIS projects are allocated to the projects for developments of the GIS applications. Especially, the 78 local governments are major users of GIS application systems. In spite of GIS necessity in local government, whether a GIS is 'good' or bad, depends on its implementation and operation. How to implement GIS in effective wav and how to measure GIS effect for justifying GIS funding can be major concerns. Because it takes minimum 3-4 years to equal the costs and benefits of GIS, the long-terms implementation strategies for GIS project in local government are required. In order to establish a proper implementation model for the GIS application projects and to promote activities in the projects, this study considers several problems in accordance with the phases of GIS evolution and solutions of these problems. Based an the GIS auditing and consulting experience in local governments, this study constructs a GIS implementation and maintenance model in long and comprehensive perspective. This model can be a key to affective and realistic implementation for the future GIS projects.

• Journal of Digital Contents Society
• /
• 제19권8호
• /
• pp.1603-1615
• /
• 2018

In order to achieve the low complexity and area, power in the design of Optical Image Stabilization (OIS) suitable for the smart phone, this paper presents the following design explorations, such as; optimization of gyroscope sampling rate, simple and accurate gyroscope filters, and reduced operating frequency of motion compensation, optimized bit width in ADC and DAC, evaluation of noise effects due to PWM driving. In experiments of gyroscope sampling frequencies, it is found that error values are unvaried in the frequency above 5KHz. The gyroscope filter is efficiently designed by combining the Fuzzy algorithm, to illustrate the reasonable compensation for the angle and phase errors. Further, in the PWM design, the power consumption of 2MHz driving is shown to decrease up to 50% with respect to the linear driving, and the imaging noises are reduced in the driving frequency above 2MHz driving frequency. The operating frequency could be reduced to 5KHz in controller and 10KHz in driver, respectively, in the motion compensation. For ADC and DAC, the optimized exploration experiments verify the minimum bit width of 11bits in ADC as well as 10bits in DAC without the performance degradation.

• Journal of Energy Engineering
• /
• 제25권4호
• /
• pp.159-169
• /
• 2016

In this study, the effects of MTBE contents as oxygenates in gasoline on exhaust emissions and fuel economy in MPI and GDi vehicles have been investigated. Various oxygen contents have been selected such as 0, 1.0, 2.3 and 2.7 wt%. FTP-75 and HWFET modes as fuel economy test methods which are widely used in Republic of Korea and US were applied to investigate exhaust emissions from the test vehicles. Emissions of CO, NMHC and NOx did not show significant correlation with oxygen contents in gasoline fuels, although having slight difference with these contents. In addition, CO2 emissions were not significantly changed with respect to oxygen content. But in case of warm-up and FTP-75 and HWFET modes including high speed regimes, CO2 emissions showed inverse correlation with oxygen contents. Particulate number concentration was inversely proportional to the oxygen contents, having the minimum value at the condition of 2.3 wt%. In case of fuel economy through carbon balance method, the highest value has been obtained at 2.3 wt% and there was positive correlation with oxygen contents and fuel economy.

• 한국해양학회지
• /
• 제30권5호
• /
• pp.371-381
• /
• 1995

To investigate the concentrations and transport patterns of particulate metals in river suspended matters, eighteen samples were collected from a fixed station located in the upper part of the Keum River through one year, and analysed for major elements (AI, Fe, P, Mn) and trace elements (Cr, Co, Ni, Cu, Zn, Cd, Pb, U). The contents of metals in suspended particulate matters (SPM) varied greatly with season and SPM load; maximum value in winter with low SPM level and minimum value in flood period and in spring Yangtze SPMs. The different trace metal level between rivers of Korea and China may be caused by the different geology of drainage basin(U) and by the different extent of anthropogenic input (Mn, Pb). Most of all particulate metals (>70%) except Mn, P and Cd were transported in the flood period with high water discharge and high suspended load. The magnitude of each transport phase (dissolved, non-detrital and detrital metals) was compared. The portions of labile metals (dissolved plus non-detrital metals) in the aquatic environment were in the range of 50%(Co) to 92%(Mn) of total metal transport and in the rank of Mn>Cd, U>Cu>Zn>Ni>Pb>Co.

• 한국해양학회지
• /
• 제2권1_2호
• /
• pp.24-33
• /
• 1967

The variations of monthly mean sea levels along the coast of Korea anre studied graphic and harmonic methods with the data from 9 tides stations and compared with the variations of atmospheric pressure and the changes in density of sea water measured near some of the stations. The monthly mean sea level generally rises in Summer to Autumn, and falls in Winter to Spring and its range is from 20 cm to 50 cm. The variation of monthly mean sea level is of annual type, having one maximum and one minimum. The semi-range of annual components is 10.5 cm at Pusan and increases to the north in the west coast, to 20.8 cm at Inchon. It's phase is, on the whole, similar for the entire coast with about 210 (middle of August), except at Inchon, 200 . The variation of monthly mean sea level is mainly isostatic, or caused by those of sea water density and atmospheric pressure. Especially, the steric effect is predominant on the south- east coast around Pusan. However, in shallow long bays and estuaries on the west coast, the river runoff effect as well as local wind effect is also considerable. Magnitudes of annual variations at each stations are not constant, but widely variable from year to year. On the east and south coast, especially at Ulneungdo and Pusan the variations are large, which seem to be connected with the shifting of main current axes or current patterns in the offing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• 제19권1호
• /
• pp.15-22
• /
• 2008

In this paper, we propose a numerical analysis on reversed current of distributed amplifier based on transmission line theory and proposed a theory to obtain optimum transmission line length to minimize the reversed currents by cancelling those components. The reversed current is analyzed as being simply absorbed into the terminal resistance in the conventional analysis. In the proposed analysis, however, they are designed to be cancelled by each other with opposite phase by the optimal length of the transmission lint Circuit simulation and implementation using pHEMT transistor were performed to validate the proposed theory with the cutoff frequency of 3.6 GHz. From the measurement, maximum gain of 14.5dB and minimum gain of 12.3dB were achieved In the operation band. Moreover, measured efficiency of the proposed distributed amplifier is 25.6% at 3 GHz, which is 7.6%, higher than the conventional distributed amplifier. Measured output power Is about 10.9dBm, achieving 1.7dB higher output power than the conventional one. Those improvement is thought to be based on the cancellation of refersed current.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권10호
• /
• pp.4285-4289
• /
• 2015

Purpose: Blood hemoglobin levels are known to influence response to radiotherapy. This retrospective analysis compared the effect of hemoglobin levels upon response to radiation among patients treated with radiation alone (by accelerated hyperfractionated radiotherapy) versus those treated with concurrent cisplatin chemoradiotherapy. Materials and Methods: Among patients treated for locally advanced carcinoma of the cervix (LACC) during 2009-10, a total of 60 fulfilled the eligibility criteria. In this time frame, external beam radiotherapy was delivered with either concurrent chemoradiotherapy (CRT, n=31) (45Gy over 25 fractions, with weekly cisplatin at 40mg/m2), or with accelerated hyperfractionated radiotherapy (AHRT, n=29) (20Gy over 10 daily fractions over the first two weeks, followed by 30Gy over 20 fractions over the next two weeks, with two fractions of 1.5Gy per day, without the use of chemotherapy). Mean weekly hemoglobin (MWH) levels of all patients were calculated as the arithmetic means of weekly recorded blood hemoglobin levels. As per MWH, patients in both of the AHRT or the CRT groups were classified into two subgroups-those with MWH between 10-10.9g/dL, or with MWH>11g/dL. Complete response (CR) to external beam RT phase (prior to brachytherapy) was declared after clinical examinations and computed tomography. The CR rate was noted for both MWH sub-groups within each of the AHRT and CRT groups. Results: Within the AHRT group, patients with MWH>11g/dL had a much better CR rate in comparison to those with MWH:10-10.9g/dL (80% vs. 21.1%) which was statistically significant (p 0.0045). Within the CRT group, there was no significant difference in the outcomes within the MWH>11g/dL and MWH:10-10.9g/dL sub-groups (CR rates of 80% vs. 61.9%, p=0.4285). Conclusions: The importance of maintaining a minimum hemoglobin level of 11g/dL during RT is much greater for patients treated with RT alone, than for patients treated with concurrent chemoradiotherapy. Enhanced haemoglobin levels during RT may to an extent negate the ill-effects that may otherwise arise due to non-use of concurrent chemotherapy.