• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.742-747
• /
• 2008

Formaldehyde(HCHO) and total volatile organic compounds(VOCs) can cause adverse health effects to the building occupants and may contribute to symptoms of 'Sick Building Syndrome'. These chemical contaminants are emitted from furnishings and electronic equipments as well as building materials. The purpose of this study is to measure and analyze VOCs and HCHO emission concentration from furnitures composed of wood materials including various chemicals by the large chamber method. This paper presents experiment results on the emission concentration of TVOCs and HCHO released from furnitures, such as bed, kitchen, sofa and table by a large chamber($24m^3$). The temperature and air humidity in the chamber are controlled to $25{\pm}1{\circ}C$ and $50{\pm}5%$ for this experiment. When the air change rate is $0.5hr^{-1}$, the background concentrations within the large chamber are below $50{\mu}g/m^3$ for TVOC, $5{\mu}g/m^3$ for HCHO and individual VOCs. The study is investigated the characterization of the chemical emission TVOC and HCHO concentrations and unknown VOCs from 6 furnitures.

• Clean Technology
• /
• v.21 no.4
• /
• pp.229-234
• /
• 2015

Recently, there are increasing numbers of study regarding hydrogen fuels but researches on desulfurization of diesel are rare. In this study, we performed diesel desulfurization reactor design by computation fluid dynamics simulation. By analyzing the change in flow and sulfur concentration at the outlet according to the changes in flow rate, reactor length, and reactor diameter, we have found the minimum catalyst performance for the given flow rate condition and the relation between the reactor performance and the reactor size and shape. We also studied the effects of permeability of the packed bed on the flow and sulfur concentration distribution. The present work can be utilized to design a diesel desulfurization reactor for a fuel cell used in ships. Furthermore, the present work also can be used to design low sulfur diesel supply in oil refineries and therefore contribute to the development of clean petrochemical technology.

• Journal of Korea Water Resources Association
• /
• v.47 no.6
• /
• pp.513-522
• /
• 2014

Climate change and urbanization have affected a increase of peak discharge and water pollution etc. In a view of these aspects, the LID(Low Impact Development) technology has been highlighted as one of adjustable control measures to mimic predevelopment hydrologic condition. Many LID technologies have developed, but there is a lack of studies with verification of LID technology efficiency. Therefore this study developed a rainfall-runoff simulator could be possible to verify LID technology efficiency. Using this simulator, this study has experimented the rainfall verification through the rainfall distribution experiment and the experiment to show the relation between inflow and effective rainfall in order to sprinkle the equal rainfall in each unit bed. As a result, the study defined the relation between allowable discharge range and RPM by nozzle types and verified the hydrologic cycle such as the relation between infiltration rate, surface runoff and subsurface runoff at pervious area and impervious area through the rainfall-runoff experiment.

• Journal of the Korea Society for Simulation
• /
• v.20 no.1
• /
• pp.61-67
• /
• 2011

Smart TV System will lead to drastic change of communication and media industries as one of the emerging next generation network services. However, when the number of concurrent users increases rapidly, the issue of service quality degradation occurs because providing services to many users simultaneously stresses both the server and the network. The server limitation can be circumvented by deploying server clusters. but the network limitation is far less easy to cope with, due to the difficulty in determining the cause and location of congestion and in provisioning extra resources. In order to alleviate these problems, a number of schemes have been developed. Prior works mostly focus on reducing user-centric performance metrics of individual connection, such as the round-trip time(RTT), downloading time or packet loss rate, but tend to ignore the network loads caused by the concurrent connections or global network load balance. In this work, we make an in-depth investigation on the issue of user grouping for massive Smart TV services through simulations on actual Internet test-bed, PlanetLab.

• Journal of the East Asian Society of Dietary Life
• /
• v.13 no.4
• /
• pp.284-292
• /
• 2003

This study was conducted to investigate the changes of dietary attitudes and behaviors in relation to the use of computers of elementary school children in Seoul. The total of 451 elementary school children, consisting of 235 females and 216 males, participated in the study. The result of domestic characteristics, dietary attitudes and behaviors, the level of the use of computers, and health-related symptoms of the subjects were achieved through the questionnaires as follows: The average height, weight, BMI and obesity-index of the participants were 149.0 cm, 42.4 kg, 19.0, -8.6, respectively. Anions subjects, 42.8％ answered their bed times were between 11~12 pm, and 82.4％ answered that they had extracurricular activities. The most desired activity as their leisure was computer works (female: 44.3％, male: 62.5％). 38.4％ of children used the computers for 1~2 hours a day and the most general usage of computers was a computer game (66.1％). The changes in dietary habits of the subjects were such as eating faster(30.2％), having lots of snacks(28.8％), eating anything at hand(26.4％), skipping breakfast due to over-sleeping(18.4％). As changes in life patterns, those in the time managements for watching T.V.(35.3％), reading(35.0％), exercising(31.9％), sleeping(27.5％), relaxing(27.5％) and other hobbies(26.4％) were observed. In conclusion, many children were being affected by the socioeconomic factors changing the environments, especially by the need for the use of computers. The rates of eating alone and skipping breakfast were getting higher in the dietary patterns of elementary school children. We found that the changes in social environments according to the heavy use of the computer were affecting on their dietary pattern. The direction and method of nutrition education had to be established for the proper understanding of the desirable dietary behaviors.

• Journal of Korean Public Health Nursing
• /
• v.19 no.1
• /
• pp.53-63
• /
• 2005

The purpose of this study was to identify menstrual discomforts and coping m adult women. The subjects were 577 adult women. aged 20 years old and over. selected by convenient sampling. Data were collected through a questionnaire survey from December 2. 2004 to December 31. 2004. Two instruments were modified and used in this study. the Menstrual Discomfort Questionnaire by Park(1988) and the Menstrual Coping Questionnaire by Billings & Moos(198l). The data were analyzed by descriptive statistics. t-test. and ANOVA with SPSS 10.0 program. The results of this study were as follows. 1. The prevalence rate of dysmenorrhea was $85.6\%$. 2. The total mean score for menstrual discomforts was 2.82 of a possible total of 5. The mean score for each category was 3.10 for water retention. 2.93 for negative affect. 2.89 for pain. 2.74 for autonomic reactions. 2.73 for behavioral change. and 2.59 for concentration. 3. Statistical differences were found for menarche age(F=9.351. p<.00l), feeling to menstruation(F=12.376. p<.001). dysmenorrhea(t=7.3l7. p<.001). onset of dysmenorrhea (F= 12.766. p<.001). taking medication(t=6.289. p<.001). and degree of taking medication (F=12.924. p<.00l). 4. The coping modes with the highest scores were 'rest and go to the bed '$(83.3\%)$. 'regard menstruation as a physiological and temporary phenomenon' $(68.6\%)$, and 'take a warm shower' $(64.5\%)$. We conclude that there were many women with dysmenorrhea. that the first day was the onset of menstrual discomfort. and that it differed by menarche age. feeling to menstruation. dysmenorrhea. onset of dysmenorrhea. taking medication. and degree of taking medication. Nursing intervention has to be considered in programs to reduce menstrual discomfort.

• Child Health Nursing Research
• /
• v.9 no.1
• /
• pp.28-35
• /
• 2003

Purpose: The purpose of this study is to investigate correlations in vital sign changes, the severity of pain, signs of complications, and the duration of sandbag management in order to suggest a standardized practice related to sandbag management in children with Nephrotic Syndrome(NS). Method: From October 2000 to May 2001, seventy children with NS who underwent kidney biopsy were interviewed at one hospital in Seoul Korea, and participated in this study. Result: 1) The average sandbag applying time after kidney biopsy was 18.1 hours. 2) Systolic blood pressure and respiration increased until 15 minutes after kidney biopsy, after then, they decreased signifi- cantly (systolic BP, p= .006; respiration, p= .029). However, no significant changes were noted in diastolic blood pressure and pulse. 3) Pain was reported minimal for 1 hour after kidney biopsy. The severity of pain increased until 12 hours after the procedure, then, decreased significantly(p= .0001). 4) Reported complications were hematuria (74.7％) and abnormal sonogram (32.9％). No apparent bleeding on the biopsy region was reported in any children. Conclusion: From these findings, it is possible to change the protocols of the duration of absolute bed rest time and sandbag application management shortly after kidney biopsy. But it is needed to study the fit protocols for kidney biopsy. Several implications in nursing practice are suggested. 1) Replicated studies for more participants are needed. 2) Further research on the effect of sandbag application after kidney biopsy is required. 3) The best duration of sandbag application management after kidney biopsy need to be investigated.

• Journal of the Korean housing association
• /
• v.19 no.6
• /
• pp.145-155
• /
• 2008

This study examined the actual use and users‘ satisfaction with the university dormitories in Gwangju and Chonnam and analyse the related variables that affect on them. Self-administered questionnaires were provided to 200 university students from Gwangju and the Chonnam area. The collected data was used to conduct comparative and descriptive statistical analysis: T-test Below are the study findings. Female students express more satisfaction with community affinity than male students in the satisfaction about socio-psychological environment. Students residing in the rooms for 2 persons express more satisfaction with the division of private space with common space, study appropriateness etc. than those residing in the rooms for 4 persons. Students residing in the cluster-type rooms express more satisfaction with the division of private space with common spaces study appropriateness and relationship with other students in other rooms etc. In relation to the room environment, female students express less dissatisfaction with the noise than male students. Students residing in the rooms for 2 persons express more satisfaction with the room size, interior temperature pleasantness, brightness etc. than those residing the in rooms for 4 persons. Students residing in the cluster-type rooms express more satisfaction with the bed size, the condition of interior finishing, interior temperature pleasantness, brightness and interior air pleasantness etc. than those residing in unit-rooms. In relation to common using environment, male students express more satisfaction with the library than female students. And students residing in the rooms for 4 persons and those residing in the cluster-type rooms express more satisfaction with lounge than those residing in the rooms for 2 persons and those residing in the unit-rooms. Organizing the university domitory planning according to the students' demands, based on this study, the change to general function of domitory in sleeping, studying, leisure activity and culture acitivity is needed. Interior environment technical factor of interior air pleasantness and noise should be improved.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.15 no.3
• /
• pp.188-198
• /
• 2010

Recently, as the demand of the environmental-friendly energy storage system such as an electric double-layer condenser increases, that of the bidirectional charger/discharger for the systems also increases. However, when charging/discharging mode-change occurs, the charger/discharger employing a bi-directional DC-DC converter with a commercialized analog controller has a complex circuit scheme, and a poor transient response. On the other hand, if a single digital controller is used for the bi-directional mode, the system performances can be improved by application of an advanced power-processing algorithm. In the paper, an environmental-friendly power storage systems including an Electric Double Layer Capacitor(EDLC) banks were developed with a bi-directional buck-boost converter and a digital signal processor (TMS320F28335). A simulation test-bed was realized and tested by MATLAB Simulink, and the hardware experiment was performed which shows that the dynamic response was improved such as the simulation results.

• Journal of East-West Nursing Research
• /
• v.6 no.1
• /
• pp.37-45
• /
• 2001

The purpose of this study was to identify the effect of hand acupuncture for reduction of dysmenorrhea. 71 female middle school and high school students were selected as subjects from April to May 2001, among which 38 students consisted of the experimental group while 22 students were the control group by convenient assignment. The experimental group participated in hand acupuncture treatment. The experimental treatment was to puncture corresponding points(A4, A5, J1, J3, J23, H2, F7) on both the palm and back of a hand with disposable acupuncture needles and to remove needles after 20-30 minutes' recess during which the subjects reposed themselves on bed. The collected data were processed using the SPSS PC Program and analyzed using $X^2test$ and The results of this study were as follows 1. The symptoms of premenstrual syndrome have decreased, but no significant differences were statistically observed between hand-acupunctured group and non-hand acupunctured group. 2. Subjective pain degree has decreased after hand acupuncture. 3. As for objective pain degree, a significant reduction in voice change was observed between two groups. Facial expressional changes and perspiration degree reduced but showed no significant statistically changes between two groups. 4. Comfort has increased after hand acupuncture. These results suggest that the hand acupuncture therapy works effectively on easing menstrual pain and symptoms as well as partially on reducing discomfort. It is particularly efficacious for a reduction in subjective pain and facial expressional changes in positive respect. Therefore the hand acupuncture therapy can be considered as an independent nursing intervention for dysmenorrhea reduction.