• Title/Summary/Keyword: E-Journal Management

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Ecological Characteristics and Management Program for Buffer Greens at Sinhyeon-Eup, Geoje-Si (거제시 신현읍 완충녹지의 생태적 특성 및 관리방안)

  • SaGong, Young-Bo;Lee, Soo-Dong
    • Korean Journal of Environment and Ecology
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    • v.21 no.3
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    • pp.243-256
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    • 2007
  • The purpose of this paper is aimed at identifying the planting condition of greenbelt axis covering forests located at Sinhyeon-eup, Geoje-si and also establishing improvement plans for the ecological organization. The study was executed with buffer green space designed to mitigate noise, which is located at a halfway point linking Mt. Yukkyo(altitude of 50m) and Mt. Jungmae(altitude of 131m). The number of the biotope patterns was classified into 17 in total: the two are urbanized districts such as a townified district and streets and another 15 are greenbelts and open space such as forest biotope, inland water biotope, and landscaping tree plantations biotope. According to the analysis of biotope types, it was estimated that the making use of already established buffer greens as a linking medium with a foothold of Mt. Yukkyo and Jungmae, whose natural eco-system is well suited for habitation of living organism, is the one and only way to the influx of living organism into the downtown area. The green coverage rate of the base green area, sub-base green area and linkage green area was 160.29%, 128.37% and 44.37% respectively; the green capacity coefficient(i.e. GVZ[$Gr{\ddot{u}}nvolumezahl$]) for base green area, sub-base green area and linkage green area was $4.04m^3/m^2,\;3.95m^3/m^2\;and\;0.65m^3/m^2$ respectively. The base green area has constituted multi-layered vegetation structure and thus played a role as habitats for living organism and supply centre of species, whereas the sub-base green area has destroyed lower layer vegetation, and the linkage green area was in bad shape due to the lack of planting volume and damage of the shrub layer. Accordingly, this research paper intended to suggest detailed implementation plans for the improvement in landscape for city dwellers' use and relaxation; in other words, this paper focused on ecological build-up for the Influx of wild birds into the downtown area for the promotion of bio-diversity of species through the linkage of base green areas and the fostering of nature observing trails for citizens as well as the connecting of green areas through the build-up of roadside greens to make these green areas to be efficiently used as corridors for the influx of wild birds and bio-organism habitation and for citizens' using space.

Toxicological Effects of Some Insecticides against Welsh Onion Beet Armyworm (Spodoptera exigua) (Metaflumizone을 포함한 몇 가지 약제의 파밤나방(Spodoptera exigua)에 대한 독성검정)

  • Kang, E.J.;Kang, M.G.;Seo, M.J.;Park, S.N.;Kim, C.U.;Yu, Y.M.;Youn, Y.N.
    • Korean journal of applied entomology
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    • v.47 no.2
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    • pp.155-162
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    • 2008
  • The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.

Development of Internet Information Push-Delivery System Design of Smoking Cessation for Health Promotion (지역주민의 건강증진을 위한 인터넷 금연 강화 프로그램 개발)

  • Kim, Young-Bok;Shin, Jun-Ho;Kim, Shin-Woel
    • Journal of agricultural medicine and community health
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    • v.29 no.2
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    • pp.287-301
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    • 2004
  • Objectives: The development of internet programs for smoking cessation was motivated to quit smoking in the large group of smokers. This personalized program consisted of tailored message to consider the smokers characteristics, and contain the informations on the outcomes of smoking cessation and the skills to be used in the quit attempts. The purpose of this study was to develop the internet management program and information push-delivery system for smoking cessation to encourage the personal intention to quit smoking. Methods: We conducted in 3 steps as developing push service to encourage intention of smoking cessation, analyzing problems of smoking cessation program through the pilot test and suggesting improvements by implication stages. Results: This program is delivered for 30 days. if the participants do not fail to quit smoking. The contents consisted of 13 stages which were divided on starting period. practical period, maintenance period and success period. And push service afforded the tailored message to participants using their e-mail. According to the evaluation of pilot test, the problems of internet information push-delivery service for smoking cessation were the over-tasks per visiting time, recording style of participants, difficulty of terms and sentences, lack of visual effects, absence of follow-up module and unsuitable link with main homepage. Improvements were divided on 3 stages by implication period. The first stage included the immediate improvements as improving link with homepage, modifying menu of smoking information and upload file of notice part. The second stage included the short term improvements as alleviating condition of withdrawal, coordinating start stage of retrial, modifying errors of information push-delivery service and addition of educational materials. The third stage included the long term improvements as development of follow-up module, cost-effectiveness evaluation, reducing contents quantity, introduction of checking style, compensation of graphics effect and review for SMS utilization. Conclusions: This program contribute to improving smoking cessation rate. Therefore this program should be tested in a community to evaluate the effectiveness. To promote the effectiveness, this program should be developed the contents and the strategies for various targets, and established the follow-up system for ex-smokers.

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A Study on the Physical Activity, Food Habit and Nutrient Intakes of Adults in Pusan (부산지역 일부 성인들의 신체활동, 식습관 및 영양소섭취상태에 관한 연구)

  • Lim, Hwa-Jae
    • Korean Journal of Community Nutrition
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    • v.15 no.4
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    • pp.460-474
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    • 2010
  • This study was performed to assess the physical activity, food habit and nutrient intakes by gender and age groups in 193 adults aged 20-59 years (84 men and 109 women) in Pusan. Data for physical activity and dietary survey was assessed by a questionnaire and 24hr recall method. The mean BMIs of men and women were 24.0 and 22.2 respectively and BMI of women in the 20-29 years group (20.9) was significantly lower than that of women in the 30-49 and 50-59 years group (22.7, 23.2) (p < 0.01). 56.0% for men and 44.0% for women exercised regularly. The mean exercise duration per once of men (69.7 minutes) was significantly higher than that of women (52.4minutes) (p < 0.01). The mean exercise duration per day was 36.0 minutes for men and 29.9 minutes for women. 67.9% for men and 78.0% for women often skipped meals and 68.4% for men and 69.4% for women skipped breakfast in the main. The mean energy intake of men was 2067.2 kcal and that of women was 1783.1 kcal comprised of 87.2% and 92.1% of the Estimated Energy Requirements (EER). The mineral intakes of men and women were over Recommended Intake (RI) and Adequate Intake (AI) except calcium and potassium. The mean calcium intake was 88.3% for men and 84.0% for women of RI. The mean potassium intake was 63.3% for men and 59.2% for women of AI. The mean vitamin intakes of men and women were over RI and AI except vitamin C and folic acid. The mean vitamin C intake was 92.5% for men and 85.6% for women of RI. The mean folic acid intake was 76.6% for men and 70.0% for women of RI. The mean energy, protein, sodium and zinc intakes of men were significantly higher than those of women (p < 0.01, p < 0.05, p < 0.05, p < 0.05). The mean vitamin $B_6$, vitamin C and folic acid intakes of men in the 20-29 years group were significantly lower than those of men in the 30-49 and 50-59 years group (p < 0.01, p < 0.05, p < 0.05). For energy, proportions of subjects with intake levels less than 90% EER were 64.3% for men and 56.0% for women. For calcium, proportions of subjects with intake levels less than Estimated Average Requirement (EAR) were 52.4% for men and 59.6% for women. For folic acid, proportions of subjects with intake levels less than EAR were 78.6% for men and 83.5% for women. For iron and phosphorus, proportions of women (36.7%, 14.7%)with intake levels less than EAR were significantly higher than those of men (6.0%, 1.2%) (p < 0.01, p < 0.001). For men, age was positively correlated with intakes of potassium, vitamin $B_6$, vitamin C and folic acid (p < 0.05, p < 0.05, p < 0.05, p < 0.01). For men, weight showed significantly negative correlations with intakes of carbohydrate, phosphorus, potassium, zinc, vitamin $B_6$ and folic acid (p < 0.01, p < 0.05, p < 0.05, p < 0.05, p < 0.01) and BMI showed significantly negative correlations with protein, lipid, phosphorus, potassium, zinc, vitamin E and folic acid (p < 0.05, p < 0.05, p < 0.05, p < 0.05, p < 0.05, p < 0.05, p < 0.05) For men, exercise duration per once showed significantly positive correlations with intakes of calcium, phosphorus, potassium, zinc, vitamin $B_1$, vitamin $B_2$, niacin, vitamin C and folic acid (p < 0.01, p < 0.05, p < 0.01, p < 0.05, p < 0.05, p < 0.01, p < 0.01, p < 0.01, p < 0.05). Therefore, nutritional education for adult health management is needed by gender and age groups.

An Analysis of Growth Conditions of old Trees in Yangdong Villages (양동마을의 노거수 생육실태 분석)

  • Kim, Young-Hun;Deng, Bei-Jia;You, Ju-Han
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.2
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    • pp.95-107
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    • 2020
  • The purpose of this study is to provide the basic data by analyzing and analysing the Growth Conditions of old Trees in Yangdong village. This study investigated about the conducted on tree information, soil information, and tree health. The result are as follows. The trees information in Yangdong Village consists of Juniperus chinensis, Salix chaenomeloides, Salix pseudolasiogyne, Celtis sinensis, Zelkova serrata, Gleditsia japonica, and Gleditsia sinensis trees, The range of height was 4.0~17.0m, and the diameter was 0.51~1.34m, Juniperus chinensis trees of No.17 was most large. In the results of soil analysis, there showed that acidity was pH4.1~6.3, hardness of 5~48mm, organic matter content of 21.2~29.1g/kg, electrical conductivity(EC) of 0.34~1.76dS/m, available P2O5 of 79.8~451.6mg/kg, exchangeable K of 0.22~1.71cmol+/kg, exchangeable Ca of 4.98~7.44cmol+/kg, exchangeable Mg of 0.67~2.19cmol+/kg, exchangeable Na of 0.19~1.04cmol+/kg and cation exchange capacity(C.E.C) of 7.23~13.02cmol+/kg. As a result, the highest number of tree health levels is 8 of 11trees of Celtis sinensis, 2 of 7trees of Zelkova serrata, and 3 of Gleditsia sinensis, and 13 of 30 trees of health levels, The Older trees with high infection, spoil and hollowed part were the remaining trees except for the healthy part. Relatively, more than half of the number of targets is infected, decay, and the hollowed site, and it is necessary to perform surgery on the damaged area. In addition, preservation and protection measures should be implemented by supplying root nutrients for trees, controlling nutrients in the body to prevent secondary and tertiary damages that cause the infection site to metastasize to the health site, In order to continually monitor the trees, measures to improve the location environment and management of the trees should be sought.

Prediction of Evapotranspiration from Grape Vines in Suwon with the FAO Penman-Monteith Equation (FAO Penman-Monteith 공식을 이용한 수원지역 포도 수체 증발산량 예측)

  • Yun, Seok-Kyu;Hur, Seung-Oh;Kim, Seung-Heui;Park, Seo-Jun;Kim, Jeong-Bae;Choi, In-Myung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.3
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    • pp.111-117
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    • 2009
  • Food and Agricultural Organization (FAO) Penman-Monteith (PM) equation is one of the most widely used equations for predicting evapotranspiration (ET) of crops. The ET rate and the base crop coefficients ($K_{cb}$) of the two different grape vines (i.e., Campbell Early and Kyoho) cultivated in Suwon were calculated by using the FAO PM equation. The ET rate of Campbell Early was $2.41\;mm\;day^{-1}$ and that of Kyoho was $2.22\;mm\;day^{-1}$ in August when the leaf area index was 2.2. During this period, the $K_{cb}$ of Campbell Early based on the FAO PM equation was on average 0.49 with the maximum value of 0.72. On the other hand, the $K_{cb}$ of Kyoho was averaged to be 0.45 with the maximum value of 0.64. The seasonal leaf area index for two grape cultivars was measured as 0.15 in April, 0.5 in May, 1.4 in June, 2.2 in July-September, and 1.5 in October. The $K_{cb}$ of Campbell Early showed a seasonal variation, changing from 0.03 in April to 0.11 in May, 0.31 in June, 0.49 in July-September, and 0.33 in October. The magnitudes and the seasonality of $K_{cb}$ of Kyoho were similar to those of Campbell Early.

An Integrated Model based on Genetic Algorithms for Implementing Cost-Effective Intelligent Intrusion Detection Systems (비용효율적 지능형 침입탐지시스템 구현을 위한 유전자 알고리즘 기반 통합 모형)

  • Lee, Hyeon-Uk;Kim, Ji-Hun;Ahn, Hyun-Chul
    • Journal of Intelligence and Information Systems
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    • v.18 no.1
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    • pp.125-141
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    • 2012
  • These days, the malicious attacks and hacks on the networked systems are dramatically increasing, and the patterns of them are changing rapidly. Consequently, it becomes more important to appropriately handle these malicious attacks and hacks, and there exist sufficient interests and demand in effective network security systems just like intrusion detection systems. Intrusion detection systems are the network security systems for detecting, identifying and responding to unauthorized or abnormal activities appropriately. Conventional intrusion detection systems have generally been designed using the experts' implicit knowledge on the network intrusions or the hackers' abnormal behaviors. However, they cannot handle new or unknown patterns of the network attacks, although they perform very well under the normal situation. As a result, recent studies on intrusion detection systems use artificial intelligence techniques, which can proactively respond to the unknown threats. For a long time, researchers have adopted and tested various kinds of artificial intelligence techniques such as artificial neural networks, decision trees, and support vector machines to detect intrusions on the network. However, most of them have just applied these techniques singularly, even though combining the techniques may lead to better detection. With this reason, we propose a new integrated model for intrusion detection. Our model is designed to combine prediction results of four different binary classification models-logistic regression (LOGIT), decision trees (DT), artificial neural networks (ANN), and support vector machines (SVM), which may be complementary to each other. As a tool for finding optimal combining weights, genetic algorithms (GA) are used. Our proposed model is designed to be built in two steps. At the first step, the optimal integration model whose prediction error (i.e. erroneous classification rate) is the least is generated. After that, in the second step, it explores the optimal classification threshold for determining intrusions, which minimizes the total misclassification cost. To calculate the total misclassification cost of intrusion detection system, we need to understand its asymmetric error cost scheme. Generally, there are two common forms of errors in intrusion detection. The first error type is the False-Positive Error (FPE). In the case of FPE, the wrong judgment on it may result in the unnecessary fixation. The second error type is the False-Negative Error (FNE) that mainly misjudges the malware of the program as normal. Compared to FPE, FNE is more fatal. Thus, total misclassification cost is more affected by FNE rather than FPE. To validate the practical applicability of our model, we applied it to the real-world dataset for network intrusion detection. The experimental dataset was collected from the IDS sensor of an official institution in Korea from January to June 2010. We collected 15,000 log data in total, and selected 10,000 samples from them by using random sampling method. Also, we compared the results from our model with the results from single techniques to confirm the superiority of the proposed model. LOGIT and DT was experimented using PASW Statistics v18.0, and ANN was experimented using Neuroshell R4.0. For SVM, LIBSVM v2.90-a freeware for training SVM classifier-was used. Empirical results showed that our proposed model based on GA outperformed all the other comparative models in detecting network intrusions from the accuracy perspective. They also showed that the proposed model outperformed all the other comparative models in the total misclassification cost perspective. Consequently, it is expected that our study may contribute to build cost-effective intelligent intrusion detection systems.

Learning from the USA's Single Emergency Number 911: Policy Implications for Korea (미국 긴급번호 911 운영시스템에 관한 연구: 긴급번호 실질적 통합을 위한 정책 시사점 제시 중심으로)

  • Kim, Hak-Kyong;Lee, Sung-Yong
    • Korean Security Journal
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    • no.43
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    • pp.67-97
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    • 2015
  • In Korea, a single emergency number, such as 911 of the USA and 999 of the UK, does not exist. This issue became highly controversial, when the Sewol Ferry Sinking disaster occurred last year. So, the Korean government has planned to adopt a single emergency number, integrating 112 of the Police, 119 of the Fire and Ambulance, 122 of the Korean Coast Guard, and many other emergency numbers. However, the integration plan recently proposed by the Ministry of Public Safety Security seems to be, what is called, a "partial integration model" which repeals the 122 number, but still maintains 112, 119, and 110 respectively. In this context, the study looks into USA's (diverse) 911 operating system, and subsequently tries to draw general features or characteristics. Further, the research attempts to derive policy implication from the general features. If the proposed partial integration model reflects the policy implications, the model can virtually operate like the 911 system -i.e. a single emergency number system - creating inter-operability between responding agencies such as police, fire, and ambulance, even though it is not a perfect integration model. The features drawn are (1) integration of emergency call-taking, (2) functional separation of call-taking and dispatching, (3) integration of physical facilities for call-taking and dispatching, and (4) professional call-takers and dispatchers. Moreover, the policy implications derived from the characteristics are (1) a user-friendly system - fast but accurate responses, (2) integrated responses to accidents, (3) professional call-taking and dispatching & objective and comprehensive risk assessment, and finally (4) active organizational learning in emergency call centers. Considering the policy implications, the following suggestions need to be applied to the current proposed plan: 1. Emergency services' systems should be tightly linked and connected in a systemic way so that they can communicate and exchange intelligence with one another. 2. Public safety answering points (call centers) of each emergency service should share their education and training modules, manuals, etc. Common training and manuals are also needed for inter-operability. 3. Personal management to enable-long term service in public safety answering points (call centers) should be established as one of the ways to promote professionalism.

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Investigation of the effect of water chemistry on biologically mediated flocculation in the aquatic environment (수질화학 조성이 수자원환경에서의 미세 부유입자 응집 거동에 미치는 영향 연구)

  • Choi, Jeong Wooa;Lee, Byung Joon
    • Journal of Korea Water Resources Association
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    • v.50 no.11
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    • pp.715-723
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    • 2017
  • Extracellular Polymeric Substances (EPS) in the water environment assemble fine, colloidal particles, such as clays, microorganisms and biomass, in large flocs, which are eventually subject to sedimentation and deposition and determine water/sediment quality and quantity. This study hence aimed to investigate the way that water and colloidal chemistry affects EPS-mediated flocculation of colloidal particles, using a jar-test experiment. Especially, ionic strength, divalent cation and humic substances concentrations were selected as experimental variables in the jar-test experiments, to elucidate their effects on EPS-mediated flocculation. A higher ionic strength increased flocculation capability, reducing electrostatic repulsion between EPS-attached colloidal particles and enhancing particle aggregation. 0.1 M NaCl ionic strength had higher flocculation capability, with 3 times larger floc size and 2.5 times lower suspended solid concentration, than 0.001 M NaCl. Divalent cations, such as $Ca^{2+}$, built divalent cationic bridges between colloidal particles and EPS (i.e., $colloid-Ca^{2+}-EPS$ or $EPS-Ca^{2+}-EPS$) and hence made colloidal particles to build into large, settelable flocs. A small $Ca^{2+}$ concentration enhanced flocculation capability, reducing suspended solid concentration 20 times lower than the initial dosed concentration. However, humic substances, adsorbed on colloidal particles, reduced flocculation, because they blocked EPS adsorption on colloidal particles and increased negative charges and electrostatic repulsion of colloidal particles. Suspended solid concentration in the tests with humic substances remained as high as the initial dosed concentration, indicating stabilization rather than flocculation. Findings about EPS-mediated flocculation in this research will be used for better understanding the fate and transport of colloidal particles in the water environment and for developing the best management practices for water/sediment quality.

A Study on Actual Usage of Information Systems: Focusing on System Quality of Mobile Service (정보시스템의 실제 이용에 대한 연구: 모바일 서비스 시스템 품질을 중심으로)

  • Cho, Woo-Chul;Kim, Kimin;Yang, Sung-Byung
    • Asia pacific journal of information systems
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    • v.24 no.4
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    • pp.611-635
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    • 2014
  • Information systems (IS) have become ubiquitous and changed every aspect of how people live their lives. While some IS have been successfully adopted and widely used, others have failed to be adopted and crowded out in spite of remarkable progress in technologies. Both the technology acceptance model (TAM) and the IS Success Model (ISSM), among many others, have contributed to explain the reasons of success as well as failure in IS adoption and usage. While the TAM suggests that intention to use and perceived usefulness lead to actual IS usage, the ISSM indicates that information quality, system quality, and service quality affect IS usage and user satisfaction. Upon literature review, however, we found a significant void in theoretical development and its applications that employ either of the two models, and we raise research questions. First of all, in spite of the causal relationship between intention to use and actual usage, in most previous studies, only intention to use was employed as a dependent variable without overt explaining its relationship with actual usage. Moreover, even in a few studies that employed actual IS usage as a dependent variable, the degree of actual usage was measured based on users' perceptual responses to survey questionnaires. However, the measurement of actual usage based on survey responses might not be 'actual' usage in a strict sense that responders' perception may be distorted due to their selective perceptions or stereotypes. By the same token, the degree of system quality that IS users perceive might not be 'real' quality as well. This study seeks to fill this void by measuring the variables of actual usage and system quality using 'fact' data such as system logs and specifications of users' information and communications technology (ICT) devices. More specifically, we propose an integrated research model that bring together the TAM and the ISSM. The integrated model is composed of both the variables that are to be measured using fact as well as survey data. By employing the integrated model, we expect to reveal the difference between real and perceived degree of system quality, and to investigate the relationship between the perception-based measure of intention to use and the fact-based measure of actual usage. Furthermore, we also aim to add empirical findings on the general research question: what factors influence actual IS usage and how? In order to address the research question and to examine the research model, we selected a mobile campus application (MCA). We collected both fact data and survey data. For fact data, we retrieved them from the system logs such information as menu usage counts, user's device performance, display size, and operating system revision version number. At the same time, we conducted a survey among university students who use an MCA, and collected 180 valid responses. A partial least square (PLS) method was employed to validate our research model. Among nine hypotheses developed, we found five were supported while four were not. In detail, the relationships between (1) perceived system quality and perceived usefulness, (2) perceived system quality and perceived intention to use, (3) perceived usefulness and perceived intention to use, (4) quality of device platform and actual IS usage, and (5) perceived intention to use and actual IS usage were found to be significant. In comparison, the relationships between (1) quality of device platform and perceived system quality, (2) quality of device platform and perceived usefulness, (3) quality of device platform and perceived intention to use, and (4) perceived system quality and actual IS usage were not significant. The results of the study reveal notable differences from those of previous studies. First, although perceived intention to use shows a positive effect on actual IS usage, its explanatory power is very weak ($R^2$=0.064). Second, fact-based system quality (quality of user's device platform) shows a direct impact on actual IS usage without the mediating role of intention to use. Lastly, the relationships between perceived system quality (perception-based system quality) and other constructs show completely different results from those between quality of device platform (fact-based system quality) and other constructs. In the post-hoc analysis, IS users' past behavior was additionally included in the research model to further investigate the cause of such a low explanatory power of actual IS usage. The results show that past IS usage has a strong positive effect on current IS usage while intention to use does not have, implying that IS usage has already become a habitual behavior. This study provides the following several implications. First, we verify that fact-based data (i.e., system logs of real usage records) are more likely to reflect IS users' actual usage than perception-based data. In addition, by identifying the direct impact of quality of device platform on actual IS usage (without any mediating roles of attitude or intention), this study triggers further research on other potential factors that may directly influence actual IS usage. Furthermore, the results of the study provide practical strategic implications that organizations equipped with high-quality systems may directly expect high level of system usage.