• Journal of Intelligence and Information Systems
• /
• v.17 no.4
• /
• pp.157-173
• /
• 2011

As the Internet use explodes recently, the malicious attacks and hacking for a system connected to network occur frequently. This means the fatal damage can be caused by these intrusions in the government agency, public office, and company operating various systems. For such reasons, there are growing interests and demand about the intrusion detection systems (IDS)-the security systems for detecting, identifying and responding to unauthorized or abnormal activities appropriately. The intrusion detection models that have been applied in conventional IDS are generally designed by modeling the experts' implicit knowledge on the network intrusions or the hackers' abnormal behaviors. These kinds of intrusion detection models perform well under the normal situations. However, they show poor performance when they meet a new or unknown pattern of the network attacks. For this reason, several recent studies try to adopt various artificial intelligence techniques, which can proactively respond to the unknown threats. Especially, artificial neural networks (ANNs) have popularly been applied in the prior studies because of its superior prediction accuracy. However, ANNs have some intrinsic limitations such as the risk of overfitting, the requirement of the large sample size, and the lack of understanding the prediction process (i.e. black box theory). As a result, the most recent studies on IDS have started to adopt support vector machine (SVM), the classification technique that is more stable and powerful compared to ANNs. SVM is known as a relatively high predictive power and generalization capability. Under this background, this study proposes a novel intelligent intrusion detection model that uses SVM as the classification model in order to improve the predictive ability of IDS. Also, our model is designed to consider the asymmetric error cost by optimizing the classification threshold. 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, when considering total cost of misclassification in IDS, it is more reasonable to assign heavier weights on FNE rather than FPE. Therefore, we designed our proposed intrusion detection model to optimize the classification threshold in order to minimize the total misclassification cost. In this case, conventional SVM cannot be applied because it is designed to generate discrete output (i.e. a class). To resolve this problem, we used the revised SVM technique proposed by Platt(2000), which is able to generate the probability estimate. 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 1,000 samples from them by using random sampling method. In addition, the SVM model was compared with the logistic regression (LOGIT), decision trees (DT), and ANN to confirm the superiority of the proposed model. LOGIT and DT was experimented using PASW Statistics v18.0, and ANN was experimented using Neuroshell 4.0. For SVM, LIBSVM v2.90-a freeware for training SVM classifier-was used. Empirical results showed that our proposed model based on SVM outperformed all the other comparative models in detecting network intrusions from the accuracy perspective. They also showed that our model reduced the total misclassification cost compared to the ANN-based intrusion detection model. As a result, it is expected that the intrusion detection model proposed in this paper would not only enhance the performance of IDS, but also lead to better management of FNE.

• Korean Security Journal
• /
• no.62
• /
• pp.135-158
• /
• 2020

In casinos, security personnel who manage the safety of customers and employees play a very important role. In particular, there is a high percentage of female employees in casinos, and because the ratio of female and male employees is similar, the probability of female customers or female employees experiencing accidents may be similar to or higher than that of males. Women's security agents who handle women's case accidents can provide female customers and employees with a security service that only women can do. However, most of the agents doing security work at casinos are male, and the proportion of women is very low. Therefore, this research is about employees who are currently working as women in casinos and conducted qualitative research to find out about various experiences they experienced while working in the casino. A total of five study participants were interviewed three times to analyze and categorize the data collected. The first question is the professor's recommendation, his personal information search and his acquaintance's recommendation. The second question, the factors behind the necessary skills at work, are various athletic skills, good physical conditions and foreign language skills. In the third question, the satisfaction factors of the task are the scarcity value of the work, the satisfaction of the pay, the suitability of the individual and the expectation of the future, and the unsatisfactory factors of the work are the risk of the work, the stress on the customer, the discrimination against the sex, the gaze around, the tiredness of the shift work. In the fourth question, factors on the need for female casino security agents are providing differentiated services to female customers, protecting female employees and providing opportunities for women in related majors. The results of this study were interviewed by an expert of more than 20 years in the casino security business, and female casino security agents said that since it is a necessary requirement, they should seek a direction for development through institutional and cognitive improvement.

• Korean Security Journal
• /
• no.19
• /
• pp.67-103
• /
• 2009

Objectives of this study is develop security services through determinants analysis on the efficiency of security works regarding security and guarding business in Korea because nowadays the modern society like Korea let alone all over the world faces the increase of dangerous factors in every security field of the human societies, and also it is the very present situation that an individual's life even the national security itself can be at the risk without guaranteeing the efficiency of the security services. For this purpose, this study reviewed related documents, surveyed and interviewed security personnels to identify what the potentially influential factors are in both the public and private security organizations regarding the efficiency of present security services and organizations, and what differences are. Also, comparing the public and private security sectors, this study intended to suggest policy agendas how to enhance the efficiency of security services in the future. This study surveyed the 177 agents and former agents of the Presidential Security Service(PSS) for the public security sector, and also surveyed, interviewed, and internet-based polled 821 randomly selected personnels for the private security sector. This research showed that regarding the efficiency of the security services number of independent variables which had positive responses in the public security sector was more than that in the private security sector. Among the 21 questions regarding this issue, there were all of 21 positive responses in the public security sector while there were 18 negative responses in the private security sector. As a result of synthesizing all the answers of the both sides, it is possible to understand that mostly the ratio of the positive response was much higher. In the public security service, statistically significant variables were budget support for events, prior access of information, an integrated teamwork training, organizational atmosphere, morale of organization personnel. However, practical training of the security service and mutual communication showed unexpectedly negative(-) signs. In the private security service, statistically significant variables were budget support for events, integrated teamwork training, socially friendly atmosphere, compensation for the personnels, bullet-proof equipments and vehicles, mood of organization, personnel recruit and disposition, unexpected incidents and basic attitude for security services. In sum, while organizational personnel variables and organizational management variables were significant in the public security service, some organizational management variables and all socio-environment variables were statistically significant at 5% significance level.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2000.11a
• /
• pp.44-63
• /
• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Journal of Food Hygiene and Safety
• /
• v.28 no.2
• /
• pp.108-114
• /
• 2013

To describe the comparative awareness between media and industry, we conducted a survey with a professional group including 28 food safety managers at food corporations and 17 food journalists to find out the differences in perception of 'reporting terms' and 'correspondence terms' when food safety incident occurs. We surveyed by questionnaire methods and did the statistical analysis by SPSS. The results showed that 70.6% of the journalists and 92.9% of the corporation workers answered 'yes indeed' about the question whether the media has a great influence when food safety incident occurs. In the perception that use of the stimulating terms of the media was the cause of company damage, 83% of the corporate workers answered 'yes indeed', and 70.6% of the journalists answered 'yes'. It means that both groups agreed on stimulating terms causing company damage. In the question whether the 'reporting terms' of the media and the 'correspondence terms' of the government and academia made a difference in the consumers' perception and the spread of the incident, 92.9% of the corporate workers and 35.3% of the journalists answered 'yes indeed'. It means that both groups showed a common opinion that the difference in choice of words expanded the perception of consumers, and the spread of the incident. However, the corporate workers agreed with this in a more serious manner than the journalist group. In standardization of 'reporting terms' and restricting use, corporate workers were overall at a positive stand while journalists showed a big difference in opinion within the group. In conclusion, it is necessary to establish a measure to standardize the terms used by corporations, journalists, and professionals in order to decrease the differences of terms and the damage of consumers and the company when food safety incident occurs.

• The Korean Journal of Air & Space Law and Policy
• /
• v.33 no.1
• /
• pp.175-204
• /
• 2018

Recently, the aviation leisure business has been legislated, and related industries have become active base with increasing the light sports aircraft within the legislation system. However, in the light sports aircraft safety problem, it is often mentioned that the flight is in violation of the regulations, the lack of safety consciousness of the operator and lack of ability, and the personal operators have a risk of accident of light aircraft such as insufficient safety management and poor maintenance. At present, the maintenance of light sports aircraft is carried out by the A & P mechanic in accordance with the relevant laws and regulations, but it is difficult to say that it is equipped with qualification and expertise. It is not a legal issue to undertake light sports aircraft maintenance work on the regulation system. However, the problem of reliability and appropriateness is constantly being raised because airplanes, light sports aircraft, and ultra-light vehicle are classified and serviced in a legal method. Although legal and institutional frameworks for light sports aircraft are separated, much of it is stipulated in the aviation law provisions. Light sports aircraft maintenance work also follows the current aircraft maintenance system. In the United States, Europe, and Australia where General Aviation developed, legal and institutional devices related to maintenance of light aircraft were introduced, and specialized maintenance tasks are covered in the light aircraft mechanics system. As a result of analysis of domestic and foreign laws and regulations, it is necessary to introduce the qualification system for maintenance of light aircraft. In advanced aviation countries such as the United States, Europe, and Australia, a light sports aircraft repairman system is installed to perform safety management. This is to cope with changes in the operating environment of the new light sports aircraft. This study does not suggest the need for a light aircraft repairman system. From the viewpoint of the legal system, the examination of the relevant laws and regulations revealed that the supplementary part of the system is necessary. It is also require that the necessity of introduction is raised in comparison with overseas cases. Based on these results, it is necessary to introduce the system into the light aircraft repairman system, and suggestions for how to improve it are suggested.

• Journal of Distribution Science
• /
• v.10 no.5
• /
• pp.45-55
• /
• 2012

In Korea, the parcel delivery service was launched officially in 1992, and the market has grown to 13.2 billion units, or 3.5 trillion won, as of 2011. The service companies accept small packages under 30 kg and deliver them on the next day in most domestic areas. This service plays an important role in business and personal activities. The parcel service companies have themselves designed the tariff for the delivery service based on two criteria: weight and the sum of three side lengths. Further, the tariff is graded in steps of three or four rate structures based on size (small, medium, large, and extra-small). However, the basic freight rate is generally decided according to the cargo's weight or measurement size, and an extra rate is added according to some factors (handling, stowability, liability, and so on). The parcel service tariff adopted by the companies is illogically designed, and this study was carried out to assess the need for redesigning the tariff structure. The cargo volume cannot be logically reflected by three side lengths. For example, two parcels measuring 160 cm based on three side lengths may have different volumes, one measuring 0.152 cbm (53.33 cm × 53.33 cm × 53.34 cm) and the other 0.05 cbm (100 cm × 50 cm × 10 cm). A small package of less than120 cm (sum of three side lengths) may have a volume of as much as 0.064 cbm (40 cm × 40 cm × 40 cm). Sample comparison showed that 17% of medium-size parcels (based on the sum of three side lengths) are small-volume packages, 24% of large-size parcels are small- or medium-volume packages, and 40% of extra-big-size parcels are big- or under-size packages. Therefore, if parcel service companies rate their services for volume cargo based on the three side lengths standard, users may have to pay higher than normal rates, particularly because a large percentage of parcels are volume cargo. According to this study, the average weight per 1 cbm is less than 300 kg. Therefore, users face an increasing risk of paying higher than logical freight charges. Generally, transportation companies are called "public interest enterprises," and parcel service companies operate as postal services. Public interest enterprises must provide the delivery service to all customers without discrimination at a reasonable service level and logical service charges. Therefore, parcels service tariffs must be designed and adopted logically. In this study, freight theories and prior research findings were used to consider the importance of freight rates, and distortion of parcel service rates based on the three side lengths system was verified through regression analysis of a parcel sample and sample comparison. In conclusion, volume sizes based on three side lengths have a higher correlation to the rate level than does the sum of three side lengths. Further, compared to the sum of three side lengths, volume size has a higher correlation to cargo weight, which is the most basic factor determining transportation cost. Therefore, the existing parcel service tariff should be changed to weight- and volume-based rates, and the tariff must be graded in steps of 8 to 10 higher rate structures for a logical freight schedule based on service cost.

• KDI Journal of Economic Policy
• /
• v.30 no.2
• /
• pp.225-270
• /
• 2008

We analyze macroeconomic consequences of pay-as-you-go (PAYGO) public pension system with a simple overlapping generations model. Contrary to large body of existing literatures offering quantitative results based on simulation study, we take another route by adopting a highly simplified framework in search of qualitatively tractable analytical results. The main contribution of our results lies in providing a sound theoretical foundation that can be utilized in interpreting various quantitative results offered by simulation studies of large scale general equilibrium models. We present a simple overlapping generations model with a defined benefit(DB) PAYGO public pension system as a benchmark case and derive an analytical equilibrium solution utilizing graphical illustration. We also discuss the modifications of the benchmark model required to encompass a defined contribution(DC) public pension system into the basic framework. Comparative statics analysis provides three important implications; First, introduction and expansion of the PAYGO public pension, DB or DC, result in lower level of capital accumulation and higher expected rate of return on the risky asset. Second, it is shown that the progress of population aging is accompanied by lower capital stock due to decrease in both demand and supply of risky asset. Moreover, risk premium for risky asset increases(decreases) as the speed of population aging accelerates(decelerates) so that the possibility of so-called "the great meltdown" of asset market cannot be excluded although the odds are not high. Third, it is most likely that the switch from DB PAYGO to DC PAYGO would result in lower capital stock and higher expected return on the risky asset mainly due to the fact that the young generation regards DC PAYGO pension as another risky asset competing against the risky asset traded in the market. This theoretical prediction coincides with one of the firmly established propositions in empirical literature that the currently dominant form of public pension system has the tendency to crowd out private capital accumulation.

• Journal of dental hygiene science
• /
• v.12 no.6
• /
• pp.558-565
• /
• 2012

The purpose of this study was to work related musculoskeletal disorders are a major. Occupational disease of the dental care profession is no exception. The survey was self-reported questionars of 300 dental hygienists that 268 dental hygienists reply to self-reported survey. This study results are as follows: Subjects of research analyzing the degree of physical musculoskeletal disorders pain, shoulder 90.3%, neck 89.2%, leg 83.6%, 81.7% back, hand/wrist/fingers 75.7%, arm/elbow, according to 52.8%. Therefore the work province of the research object people the musculoskeletal disorders appeared different. Generally characteristic was taller dental hygienists lower back pain and were out of less weight, study subjects had neck and arm pain. 29~33 year-old age the shoulder, over the age of 34 the arm/elbow to be high (p<0.05). Working environment to become a career, the more hand/wrist/fingers and the pain increased (p<0.05). The neck, shoulders (p<0.05), arm (p<0.01), waist high in the 3~4 years experience. And leg/foot was in the 1~2 years experience. This increase in working hours had increased pain in the neck but the hand/wrist/finger pain in the small hours of experience in the high pain(p<0.01). Conclusion of the musculoskeletal disorders of the dental hygienists often than the average for this risk is recognized. When it occurs early in treatment can be simple, but time is left to revert to normal when you do not already. Therefore, maintaining proper posture and dental hygienists, pain or fatigue appeared to accumulate immediately treated continued efforts are needed.

• Journal of Intelligence and Information Systems
• /
• v.25 no.3
• /
• pp.63-88
• /
• 2019

The goal of this paper is to investigate changes in North Korea's domestic and foreign policies through automated text analysis over North Korea represented in South Korean mass media. Based on that data, we then analyze the status of text mining research, using a text mining technique to find the topics, methods, and trends of text mining research. We also investigate the characteristics and method of analysis of the text mining techniques, confirmed by analysis of the data. In this study, R program was used to apply the text mining technique. R program is free software for statistical computing and graphics. Also, Text mining methods allow to highlight the most frequently used keywords in a paragraph of texts. One can create a word cloud, also referred as text cloud or tag cloud. This study proposes a procedure to find meaningful tendencies based on a combination of word cloud, and co-occurrence networks. This study aims to more objectively explore the images of North Korea represented in South Korean newspapers by quantitatively reviewing the patterns of language use related to North Korea from 2016. 11. 1 to 2019. 5. 23 newspaper big data. In this study, we divided into three periods considering recent inter - Korean relations. Before January 1, 2018, it was set as a Before Phase of Peace Building. From January 1, 2018 to February 24, 2019, we have set up a Peace Building Phase. The New Year's message of Kim Jong-un and the Olympics of Pyeong Chang formed an atmosphere of peace on the Korean peninsula. After the Hanoi Pease summit, the third period was the silence of the relationship between North Korea and the United States. Therefore, it was called Depression Phase of Peace Building. This study analyzes news articles related to North Korea of the Korea Press Foundation database(www.bigkinds.or.kr) through text mining, to investigate characteristics of the Kim Jong-un regime's South Korea policy and unification discourse. The main results of this study show that trends in the North Korean national policy agenda can be discovered based on clustering and visualization algorithms. In particular, it examines the changes in the international circumstances, domestic conflicts, the living conditions of North Korea, the South's Aid project for the North, the conflicts of the two Koreas, North Korean nuclear issue, and the North Korean refugee problem through the co-occurrence word analysis. It also offers an analysis of South Korean mentality toward North Korea in terms of the semantic prosody. In the Before Phase of Peace Building, the results of the analysis showed the order of 'Missiles', 'North Korea Nuclear', 'Diplomacy', 'Unification', and ' South-North Korean'. The results of Peace Building Phase are extracted the order of 'Panmunjom', 'Unification', 'North Korea Nuclear', 'Diplomacy', and 'Military'. The results of Depression Phase of Peace Building derived the order of 'North Korea Nuclear', 'North and South Korea', 'Missile', 'State Department', and 'International'. There are 16 words adopted in all three periods. The order is as follows: 'missile', 'North Korea Nuclear', 'Diplomacy', 'Unification', 'North and South Korea', 'Military', 'Kaesong Industrial Complex', 'Defense', 'Sanctions', 'Denuclearization', 'Peace', 'Exchange and Cooperation', and 'South Korea'. We expect that the results of this study will contribute to analyze the trends of news content of North Korea associated with North Korea's provocations. And future research on North Korean trends will be conducted based on the results of this study. We will continue to study the model development for North Korea risk measurement that can anticipate and respond to North Korea's behavior in advance. We expect that the text mining analysis method and the scientific data analysis technique will be applied to North Korea and unification research field. Through these academic studies, I hope to see a lot of studies that make important contributions to the nation.