• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.379-387
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• 1999

During the past several decades, electricity generating plant increased with remarkable rapidity in Korea. Recently the increase has been much more rapid as the rate of industrialization has accelerated. Construction of nuclear power plants in coastal areas inevitably caused the perturbation of critical coastal habitats and thus influenced marine algal species composition. Particularly, an increase in the building of nuclear power plants led the amounts of heat discharged to increase exponentially. As far as the effects of cooling water and thermal discharges are concerned, benthic marine algae are likely to be vulnerable to a discharge. Heated effluents from nuclear power plants, with the temperature rises of 7~12$^{\circ}C$ under normal operating and design conditions, are discharged through the discharge canal and into natural water bodies. It is clear that the characteristic marine algal community is developed in the area affected by the thermal discharges; i.e. low species richness and low species diversity. Nevertheless, it is worthwhile to note that elevated temperatures exert differential effects depending on the algal populations. Benthic marine algae grown at the discharge canal can be regarded as warm tolerant species. 35 species (4 blue-green, 9 green, 8 brown and 14 red algae) of marine algae occurred more than 20eye frequency at discharge canal of three nuclear power plants in the east coast during 1992 ~ 1998 and thus can be categorized as warm tolerant species in Korea. To minimize the ecological impacts of waste heat on benthic marine algae, it is recommended that, in the future, nuclear power plants will have to employ some form of closed-cycle cooling for the condensers.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.595-603
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• 2013

Touchscreen is now installed in the majority of information devices thanks to the developed digital technology. In case of copiers, although touchscreen was installed earlier than any other information device, current user interface indicates that conventional methods have been maintained without any special re-validation. But, since common office devices such as copiers have brief usage time and clear, straightforward purposes, user experience between an user and device is perhaps an important element. Nevertheless, conservativeness of the market and the fact that users and buyers are not always the same are a stumbling block to actively changing UI. Recently, however, as hardware element, buttons, have moved to touchscreen mostly for smartphone, and common and public devices have seen rapid changes in UX, mostly with touchscreen, it has led to high demand for changes in UX of copiers. To remedy the issues with copiers, a literature review was conducted through existing studies and user evaluation based on user survey and prototype was done to examine the copier's UI elements and relevant changes in usage. In particular, a new direction for UX of copiers was suggested by analyzing the impact of differences between software button-oriented UI and hardware button-oriented UI on users and usability. This study findings could be used as basic data for improving the usability of future common devices including copier and UX design.

• The Journal of Engineering Geology
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• v.13 no.3
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• pp.321-334
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• 2003

This study is aimed at the effective measurement plan of discontinuity orientation on rock mass. The discontinuity orientation is expressed as three methods. strike/dip. dipdirection/dip (a three digit number / a two digit number) and right hand rule. Generally, strike/dip is measured with clinometer. and dipdirection/dip with silva compass(type15). A sign of strike/dip. discontinuity orientation is used to geological survey. and dipdirection/dip to engineering. Dipdirection/dip converted by strike/dip measured with clinometer is useful on the statistical analysis of a lot of data. To measure the azimuth of the dip with clinometer and to change strike/dip to dipdirection/dip may have potential errors in each person. The newly designed apparatus, clinometer equipped by a rotational azimuth plate and an arrow to measuring strike and dipdirection, has been developed to measure effectively the discontinuity orientation with two method (strike/dip and dipdirection/dip). The measuring method of discontinuity orientation with clinometer having newly designed apparatus is effective one for accurate measurement of strike as well as dipdirection which is degrees counted clockwise from true north. Used by clinometer with newly designed apparatus, concurrent measuring strike/dip and dipdirecton/dip of discontinuity is possible. In application to measuring discontinuity orientation on rock slope, it has been recognized that the newly designed method, unambiguously, led to drop measuring errors comparing with existing measuring apparatuses. Therefore, it is considered that measuring method of discontinuity orientation (strike/dip and dipdirecton/dip) by the newly designed apparatus is useful to one in geological engineering investigation of road design, and to unskilled investigator.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.390-395
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• 2002

Two experiments were conducted to study the performance and carcass characteristics of Hanwoo (Korean native beef cattle) steers (Experiment 1) and the nutrient digestibility of sheep (Experiment 2) when the animals fed diets containing four levels of dried wormwood (Artemisia sp.). For both experiments the animals were given a basal diet consisting of rice straw and concentrate mixed at 3:7 ratio (on DM basis). In Experiment 1, the treatments were designed as a completely randomized design with two feeding periods. Steers were allotted in one of four dietary treatments, which were designed to progressively substitute dried wormwood for 0, 3, 5 and 10% of the rice straw in the basal diet. Bodyweight gain and average daily gain (ADG) of Hanwoo steers fed diets containing the 5 and 10% wormwood inclusion were greater (p<0.05) than the 3% wormwood-feeding group. Total and daily intakes of roughage and concentrate were not altered by all levels of dried wormwood inclusion. However, the 10% dried wormwood inclusion led to increased total feed intake (p<0.05) compared with that of the 0 and 3% of dried wormwood inclusion. Carcass weight, carcass yield and backfat thickness were not altered by dried wormwood inclusion. The highest level of dried wormwood inclusion resulted in significantly increased (p<0.05) loin-eye area compared with the 0 and 5% levels of dried wormwood inclusion. Experiment 2 was designed by a $4{\times}4$ Latin square with four periods. Sheep were allocated in one of four dietary treatments as same as in Experiment 1. Digestibilities of DM and TDN were significantly increased (p<0.05) in sheep fed the diet containing all three levels of dried wormwood inclusion compared with the control treatment. Digestibilities of CP and crude fiber in the 5% dried wormwood inclusion highly increased (p<0.05) up to 8.2 and 5.5% respectively relative to the control treatment. The palatability was significantly improved (p<0.05) by the 5% dried wormwood inclusion compared with the control treatment. It is concluded that feeding diets containing dried wormwood substituted for equal weights of rice straw at 5 and 10% levels would be anticipated to provide better quality roughage for beef cattle production and higher income for beef cattle producers.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.62-67
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• 2007

It was investigated to develop the technology for simultaneous removal of $SO_2/NO$ in flue gas using liquid homogeneous catalyst. Test was carried out using a bench scale and a pilot scale experiment. The investigation led to the following results: 1) Removal efficiency of $SO_2$ gas showed good results regardless of operating condition. Removal efficiency of NO gas, however, proportionally increased with higher packing height, lower concentration and larger injection rate of catalyst 2) The optimum design parameters for simultaneous removal of $SO_2/NO$ gas using Fe(II)-EDTA catalyst were as follow: HTU(height of transfer unit) = 0.5 m, liquid gas ratio = 20 $L/m^3$, NTU (number of transfer unit) = 3 stages, cross dimension of scrubber=0.025 $m^2$ 3) The removal efficiencies of $SO_2$ and NO were 95% and 81%, repletely. 4) The high HTU is advantageous on removal of the NO, but the excessive HTU diminishes operating efficiency. Consequently, it is important to decide the HTU of optimum.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.618-626
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• 2017

This study was conducted to investigate the factors affecting depression in elementary school teachers. The research design was a descriptive study. Methods:Data were collected by questionnaires from 283 elementary school teachers. Data were analyzed using a t-test, ANOVA, a $Scheff{\acute{e}}$ test, correlation analysis, and multiple regression analysis. Results: The mean scores were 2.44, 3.07 and 3.68 out of 5 on Likert scales for burnout, job stress and ego-resiliency, respectively. The mean scores were 1.47 and 2.95 out of 4 on Likert scales for items of depression and job satisfaction, respectively. Teaching experience and class size affected depression significantly. There was a positive correlation between depression and burnout(r=0.465, p<.001), and between depression and job stress(r =.220, p<.001),while a negative correlation was observed between depression and job satisfaction(r=-.249, p<.001), and depression and ego-resiliency(r=-.643, p<.001). Multiple regression analysis showed that ego-resiliency(${\beta}=0.639$), job satisfaction(${\beta}=.141$), burnout(${\beta}=.094$), and job stress(${\beta}=.067$) affected depression in order and the four research variables led to a 42.7% prediction for depression among elementary school teachers. Conclusion: Based on the results of this study, a systematic plan for decreasing job stress and increasing eco-resilience is needed to improve depression among elementary school teachers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.435-445
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• 2018

This study was conducted to develop and apply the health conversation program to determine its effectiveness. The study employed a pretest-posttest nonequivalent control group design. There were 25 subjects in one intervention group and 22 subjects in the control group. The program included a 4-week, 12-session education program in health conversation for professionally retired elderly mentors and an 8-week, 24-session program for vulnerable elderly diabetics provided by mentors who were older persons trained in diabetes management. Data were collected from December 2015 to May 2016 and subsequently analyzed by an independent t-test using SPSS 20.0. Biochemical variables and physical variables were assessed by blood test and Inbody 230 (Biospace). Psychosocial variables were assessed by questionnaires. The health conservation program led to significantly decreased FBS (p<0.01), TC (p<0.01), TG (p=0.04), SBP (p=0.03), waist (p<0.01) and symptoms of depression (p=0.01), and significantly increased social support (p=0.02). These results indicated that the health conservation program is effective at increasing social support and decreasing FBS, TC, TG, SBP, waist, and symptoms of depression in community-dwelling vulnerable diabetic elderly; accordingly, health conservation programs should be applied to improve quality of life of vulnerable diabetic elderly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.660-665
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• 2018

Research into underwater wireless networks that enable the monitoring and controlling of the ocean environments has been continuing for disaster prevention and military proposes, as well as for the exploitation of ocean resources throughout the world. A research group led by Hoseo university has been studying a distributed underwater monitoring and controlling network. In this study, we developed an interpolator for acoustic communication between an underwater base station controller and underwater base station, which is included in this network. The underwater acoustic communication provided by this network defines four links whose sampling rates are different. Low power consumption is one of the most important requirements. Therefore, we adopted CIC interpolators, which are known to act as filters with a low power consumption, and some CIC interpolators with an appropriate changing rate were selected depending on the link. However, these interpolators have a large passband drop and wide transition region. To solve these problems, we added a compensator and half-band filter. After verifying the algorithm by using Matlab, we designed and verified it with Verilog-HDL in a ModelSim environment.

• Journal of the Korean Regional Science Association
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• v.35 no.4
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• pp.61-73
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• 2019

Urban development and densification have led to the Urban Heat Island Effect, in which the temperature of urban space is higher than the surrounding areas, and the intensity is increasing with climate change. In addition, when the city's air temperature rises in summer, low-income, elderly population, and socially vulnerable people who have health problems lack the ability to cope with the elevated heat environment. Therefore, this study aimed to identify the urban heat island area of Seoul through Hotspot analysis, which is a spatial statistics technique, and explored physical environments, demographic and socioeconomic characteristics of urban heat island effect areas using logistic regression models. This study performed urban heat island hotspot analysis using the average air temperatures of the 423 administrative dongs in Seoul. Analysis results identified that the urban heat islands were concentrated in Jung-gu, Jongno-gu, Yongsan-gu, and Yeongdeungpo-gu. Logistic regression analysis results indicated that urban heat island areas of Seoul were affected by residential floor area ratio, commercial facility floor area ratio, overall floor area ratio, impervious surface ratio, and normalized difference vegetation index(NDVI). In addition, as a result of analyzing the vulnerable area of thermal environment considering the demographic and socioeconomic characteristics of the heat island area, urban heat island areas of Seoul were significantly associated with the proportion of low-income elderly living alone. The result of this study provided useful insights for urban thermal environmental design and policy development that could improve the thermal environment for the socially disadvantaged urban population.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.148-156
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• 2017

This study was conducted to examine the effects of a simulation-based learning method that utilizes the task of making a video for respiratory patients care. A quasi-experimental non-equivalent control group pre-post test design was used. A total of 56 students-28 students in the experimental group and 28 students in the control group were included. The experimental group received the 2 education sessions with 120 minutes in each session. It was implemented in November, 2014. Data were analyzed with paired t-test and unpaired t-test using SPSS/Win 18.0. The experimental group who had the simulation-based learning method utilizing the task of making video. It showed significantly higher learning satisfaction (p=.008 p<.001), and self-efficacy (p=.010) compared with the control group who had a traditional simulation education. Through this study, The educational effects of video-making task are the stimulation of interest in learners, improvement of self-led learning and communication skills. Therefore, a simulation-based learning method utilizing the task of making a video was an effective teaching method for the growth of professional competency for students involved in health related fields.