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The Occupant Perception and Investigation of Indoor Air Quality at Home in Seoul

  • Sohn, Jong-Ryeul;Kim, Young-Whan;Byeon, Sang-Hoon
    • Journal of environmental and Sanitary engineering
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    • v.18 no.1
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    • pp.51-57
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    • 2003
  • Indoor air quality(IAQ) in workplace and residential environments has been concern of people. Recently, Ministry of Environment in Korea has recognized the potential risk on the healthy effect related to indoor air pollution at home. Therefore, the purpose of this study was performed to measure the indoor air pollutants of IAQ at different homes and investigate to compare the perception of IAQ recognition at home from questionnaire survey in Seoul. We estimated the IAQ of selected 6 homes based on site region and housing type. The indoor air pollutants and parameters such as temperature, relative humidity, respirable suspended particulate matter($PM_{10}$), formaldehyde(HCHO), total bacteria counts, carbon monooxide(CO) and carbon dioxide($CO_2$) were monitored for summer and winter. In monitoring results, the respirable suspended particulate matter(($PM_{10}$) and indoor airborne bacteria level of home 5 and 6 were higher than the standard of the public $150{\;}{\mu}g/m^3$ and $500{\;}{\mu}g/m^3$, the level formaldehyde(HCHO) was exceed 0.1 ppm of the standard of Korea at all monitored homes. In statistics analysis, we could find a correlation between the building age and the concentration of CO, TBC were significant at 0.01 level and Relative Humidity was significant at 0.05 level for summer. Finally, the important air pollutants of IAQ in home were HCHO and total bacteria counts(TBC). And we performed a questionnaire survey of 500 people about their awareness for the importance of IAQ in our home during same period. In results, all most response of occupant has recognized the importance of IAQ at home. Therefore, it can be concluded that the IAQ of selected 6 home studied was perceived as acceptable, it is recommended that the government related IAQ was suggested the guideline and control of IAQ problems, and the occupants need to be effort to reduce the exposure of sources to undesirable pollutants.

Prediction of Late Rectal Complication Following High-dose-rate Intracavitary Brachytherapy in Cancer of the Uterine Cervix (자궁경부암 환자의 고선량률 강내치료 시행 시 직장합병증의 예측)

  • Lee, Jeung-Eun;Huh, Seung-Jae;Park, Won;Lim, Do-Hoon;Ahn, Yong-Chan
    • Radiation Oncology Journal
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    • v.21 no.4
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    • pp.276-282
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    • 2003
  • Purpose: Although high-dose-rate intracavitary radiotherapy (HDR ICR) has been used in the treatment of cervical cancer, the potential for increased risk of late complication, most commonly in the rectum, is a major concern. We have previously reported on 136 patients treated with HDR brachytherapy between 1995 and 1999. The purpose of this study is to upgrade the previous data and confirm the correlation between late rectal complication and rectal dose in cervix cancer patients treated with HDR ICR. Materials and Methods: A retrospective analysis was peformed for 222 patients with cevix cancer who were treated for curative intent with external beam radiotherapy (EBRT) and HDR ICR from July 1995 to December 2001. The median dose of EBRT was 50.4 (30.6$\~$56.4) Gy with a daily fraction size 1.8 Gy. A total of six fractions of HDR ICR were given twice weekly with fraction size of 4 (3$\~$5.5) Gy to A point by Iridium-192 source. The rectal dose was calculated at the rectal reference point using the barium contrast criteria. in vivo measurement of the rectal dose was peformed with thermoluminescent dosimeter (TLD) during HDR ICR. The median follow-up period was 39 months, ranging from 6 to 90 months. Results: Twenty-one patients (9.5$\%$) experienced late rectal bleeding, from 3 to 44 months (median, 13 months) after the completion of RT. The calculated rectal doses were not different between the patients with rectal bleeding and those without, but the measured rectal doses were higher in the complicated patients. The differences of the measured ICR rectal fractional dose, ICR total rectal dose, and total rectal biologically equivalent dose (BED) were statistically significant. When the measured ICR total rectal dose was beyond 16 Gy, when the ratio of the measured rectal dose to A point dose was beyond 70$\%$, or when the measured rectal BED was over 110 Gy$_{3}$, a high possibility of late rectal complication was found. Conclusion: Late rectal complication was closely correlated with measured rectal dose by in vivo dosimetry using TLD during HDR ICR. If data from in vivo dosimetry shows any possibility of rectal bleeding, efforts should be made to reduce the rectal dose.

A Study on derivation of drought severity-duration-frequency curve through a non-stationary frequency analysis (비정상성 가뭄빈도 해석 기법에 따른 가뭄 심도-지속기간-재현기간 곡선 유도에 관한 연구)

  • Jeong, Minsu;Park, Seo-Yeon;Jang, Ho-Won;Lee, Joo-Heon
    • Journal of Korea Water Resources Association
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    • v.53 no.2
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    • pp.107-119
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    • 2020
  • This study analyzed past drought characteristics based on the observed rainfall data and performed a long-term outlook for future extreme droughts using Representative Concentration Pathways 8.5 (RCP 8.5) climate change scenarios. Standardized Precipitation Index (SPI) used duration of 1, 3, 6, 9 and 12 months, a meteorological drought index, was applied for quantitative drought analysis. A single long-term time series was constructed by combining daily rainfall observation data and RCP scenario. The constructed data was used as SPI input factors for each different duration. For the analysis of meteorological drought observed relatively long-term since 1954 in Korea, 12 rainfall stations were selected and applied 10 general circulation models (GCM) at the same point. In order to analyze drought characteristics according to climate change, trend analysis and clustering were performed. For non-stationary frequency analysis using sampling technique, we adopted the technique DEMC that combines Bayesian-based differential evolution ("DE") and Markov chain Monte Carlo ("MCMC"). A non-stationary drought frequency analysis was used to derive Severity-Duration-Frequency (SDF) curves for the 12 locations. A quantitative outlook for future droughts was carried out by deriving SDF curves with long-term hydrologic data assuming non-stationarity, and by quantitatively identifying potential drought risks. As a result of performing cluster analysis to identify the spatial characteristics, it was analyzed that there is a high risk of drought in the future in Jeonju, Gwangju, Yeosun, Mokpo, and Chupyeongryeong except Jeju corresponding to Zone 1-2, 2, and 3-2. They could be efficiently utilized in future drought management policies.

GIS-based Disaster Management System for a Private Insurance Company in Case of Typhoons(I) (지리정보기반의 재해 관리시스템 구축(I) -민간 보험사의 사례, 태풍의 경우-)

  • Chang Eun-Mi
    • Journal of the Korean Geographical Society
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    • v.41 no.1 s.112
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    • pp.106-120
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    • 2006
  • Natural or man-made disaster has been expected to be one of the potential themes that can integrate human geography and physical geography. Typhoons like Rusa and Maemi caused great loss to insurance companies as well as public sectors. We have implemented a natural disaster management system for a private insurance company to produce better estimation of hazards from high wind as well as calculate vulnerability of damage. Climatic gauge sites and addresses of contract's objects were geo-coded and the pressure values along all the typhoon tracks were vectorized into line objects. National GIS topog raphic maps with scale of 1: 5,000 were updated into base maps and digital elevation model with 30 meter space and land cover maps were used for reflecting roughness of land to wind velocity. All the data are converted to grid coverage with $1km{\times}1km$. Vulnerability curve of Munich Re was ad opted, and preprocessor and postprocessor of wind velocity model was implemented. Overlapping the location of contracts on the grid value coverage can show the relative risk, with given scenario. The wind velocities calculated by the model were compared with observed value (average $R^2=0.68$). The calibration of wind speed models was done by dropping two climatic gauge data, which enhanced $R^2$ values. The comparison of calculated loss with actual historical loss of the insurance company showed both underestimation and overestimation. This system enables the company to have quantitative data for optimizing the re-insurance ratio, to have a plan to allocate enterprise resources and to upgrade the international creditability of the company. A flood model, storm surge model and flash flood model are being added, at last, combined disaster vulnerability will be calculated for a total disaster management system.

Lead Pollution and Lead Poisoning among Children in China

  • Zheng, Yuxin
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2003.06a
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    • pp.24-25
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    • 2003
  • Lead is ubiquitous in the human environment as a result of industrialization. China's rapid industrialization and traffic growth have increased the potential for lead emissions. Lead poisoning in children is one of the most common public health problems today, and it is entirely preventable. Children are more vulnerable to lead pollution and lead in their bodies can affect their nervous, circulatory, and digestive systems. Children are exposed to lead from different sources (such as paint, gasoline, and solder) and through different pathways (such as air, food, water, dust, and soil). Although all children are exposed to some lead from food, air, dust, and soil, some children are exposed to high dose sources of lead. Significant sources of lead for China's children include industrial emissions (often close to housing and schools), leaded gasoline, and occupational exposure that occurs when parents wear lead-contaminated clothing home from work, burning of coal for home heat and cooking, contaminated food, and some traditional medicines. To assess the blood lead level in children in China, a large-scale study was conducted in 19 cities among 9 provinces during 1997 to 2000. There were 6502 children, aged 3-5 years, were recruited in the study The result indicates that the mean blood lead level was 8.83ug/dl 3-5 year old living in city area. The mean blood lead level of boys was higher than that of girls (9.1l ug/dl vs 8.73ug/dl). Almost 30 percent childrens blood lead level exceeded 10ug/dl. The average blood lead level was higher than that of in 1985 (8.83ug/dl vs 8.lug/dl). An epidemiological study was carried on the children living around the cottage industries recycling the lead from battery. Nine hundreds fifty nine children, aged 5-12 years, living in lead polluted villages where the lead smelters located near the residential area and 207 control children live in unpolluted area were recruited in the study. The lead levels in air, soil, drinking water and crops were measured. The blood lead and ZnPP level were tested for all subjects. The results show that the local environment was polluted. The lead levels both in the air and crops were much higher than that of in control area. In the polluted area, the average blood level was 49.6ug/dl (rang 19.5-89.3ug/dl). Whereas, in the unpolluted area, the average blood level was 12.4ug/dl (rang 4.6-24.8ug/dl). This study indicates that in some countryside area, some cottage industries induce seriously lead pollution and cause children health problem. For the introducing of unleaded gasoline in some large cities, such as Beijing and Shanghai, the blood lead level showed a declined trend since 1997. By 2000, the use of leaded gasoline in motor vehicles has been prohibited in China. The most recent data available show that levels of lead in blood among children in Shanghai decreased from 8.3ug/dl in 1997 to 7.6ug/dl in 1999. The prevalence rate of children lead poisoning (blood lead >10ug/dl) was also decreased from 37.8% to 24.8%. In children living in downtown area, the blood lead level reduced dramatically. To explore the relationship between gene polymorphisms and individual susceptibility of lead poisoning, a molecular epidemiological study was conducted among children living in lead polluted environment. The result showed that the subjects with ALAD2 allele has higher ZPP level, and the subjects with VDR B allele has larger head circumference than only with b allele. In the present study, we demonstrated that ALAD genotypes modify lead effects on heme metabolism and VDR gene variants influence the skull development in highly exposed children. The polymorphism of ALAD and VDR genes might be the molecular inherited factor modifying the susceptibility of lead poisoning. Recently, Chinese government pays more attention to lead pollution and lead poisoning in children problem. The leaded gasoline was prohibited used in motor vehicles since 2000. The government has decided to have a clampdown on the high-polluted lead smelters for recycling the lead from battery in countryside. It is hopeful that the risk of lead poisoning in children will be decreased in the further

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The Study for the Relationship of Weight Loss with Plasma Leptin and TNF-α Level in Patients with Chronic Bronchitis and Emphysema (만성기관지염과 폐기종 환자에서 체중감소와 혈중 Leptin 및 TNF-α와의 관계에 대한 연구)

  • Pack, Jong Hae;Park, Ji Young;Park, Hye Jeong;Baek, Suk Hwan;Shin, Kyeong Cheol;Chung, Jin Hong;Lee, Kwan Ho
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.2
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    • pp.199-209
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    • 2003
  • Background : Unexplained weight loss, which commonly occurs in patients with chronic obstructive pulmonary disease(COPD), is important because weight loss is an independent risk factor of mortality and morbidity in these patients. Leptin is known to play an important role in regulating body weight. In addition, the tumor necrosis factor($TNF-{\alpha}$) might also play a potential role in the weight loss experienced in chronic wasting disease. The aim of this study was to determine the influence of plasma leptin and the circulating $TNF-{\alpha}$ system to the difference in the body compositions in patients with COPD. Methods : Spirometry, body composition analysis and the plasma concentrations of leptin, $TNF-{\alpha}$ and a soluble TNF receptor (STNF-R55, -R75) were measured in 31 patients with chronic bronchitis and 10 patients with emphysema. The COPD subtype was classified by the transfer coefficient of carbon monoxide, DLco/VA. Results : The circulating levels of leptin were significantly lower in those patients with emphysema($108.5{\pm}39.37pg/ml$) than those with chronic bronchitis($180.9{\pm}57.7pg/ml$). The circulating levels of sTNF-R55 were significantly higher in the emphysema patients($920.4{\pm}116.4pg/ml$) than in those with chronic bronchitis($803.2{\pm}80.8pg/ml$). There was no relationship between the circulating leptin levels and the activated TNF system in patients with chronic bronchitis and emphysema. However, the circulating leptin levels correlated well with the BMI and fat mass in both patient groups. Conclusion : These results suggest that the weight loss noted in emphysema patients may be associated with the activation of the $TNF-{\alpha}$ system rather than the plasma leptin level.

Effect of Mixture of Lactobacillus plantarum CECT 7527, 7528, and 7529 on Obesity and Lipid Metabolism in Rats Fed a High-fat Diet (Lactobacillus plantarum CECT 7527, 7528, 7529 혼합물이 고지방식이를 급여한 흰쥐의 비만 및 지질 대사에 미치는 영향)

  • Kim, Dae Hwan;Choi, Mi-Ran;Hong, Ji Eun;Lee, Jae-Yong;Lee, Soon Im;Jung, Su Hwan;Kim, Eun Ji
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.10
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    • pp.1484-1490
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    • 2014
  • In the present study, we examined the effects of a mixture of three strains, Lactobacillus plantarum CECT 7527, 7528, and 7529 (L. plantarum mixture), on body weight and lipid metabolism in Sprague-Dawley rats fed a high-fat diet. Rats were fed a high-fat diet and subjected to oral gavage with vehicle or the L. plantarum mixture ($0.6{\times}10^9$, $1.2{\times}10^9$, $2.4{\times}10^9$ colony-forming units (CFU)/day/rat, respectively) for 8 weeks. In rats fed a high-fat diet, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture significantly reduced body weight gain as well as weights of liver and epididymal fat. Leptin levels in sera were significantly reduced by oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture. The L. plantarum mixture ($1.2{\times}10^9$ or $2.4{\times}10^9CFU/day$) also reduced the concentrations of total cholesterol and LDL-cholesterol in sera when it administered orally. Further, the L. plantarum mixture significantly reduced the atherogenic index and cardiac risk factor. In addition, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture markedly reduced levels of total lipids, triglycerides, and total cholesterol in the liver. The results of this study indicate that the L. plantarum mixture may exhibit anti-obesity and cholesterol-lowering effects, which suggest that the L. plantarum mixture has the potential to be a probiotic in the management of obesity and hypercholesterolemia.

Clincal Manifestations of Patients Dying of Severe Community Acquired Pneumonia (중증 원외폐렴으로 사망한 환자의 임상적 분석)

  • Choi, Won-Il;Sohn, Jeong-Ho;Kwun, Oh-Yong;Heo, Jeong-Sook;Whang, Jae-Seok;Han, Seong-Beom;Jeon, Young-June
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.5
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    • pp.537-545
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    • 1994
  • Background: In 1987, the British Thoracic Society (BTS) subjected an extensive list of patient variables to statistical analysis in a prospective study of prognosis in 453 adults with community-acquired pneumonia and, subsequently published guidelines for management of severe community acquired pneumonia. It was hoped that those at risk of dying from community acquired pneumonia could be easily identified and treated appropriately, thereby reducing mortality. To date, severe community acquired pneumonia has not been well studied in Korea. Therefore, we studied retrospectively 10 patients dying of severe community acquired pneumonia in Dongsan Hospital to see clinical manifestations of dying of severe community-acquired pneumonia. Methods: Between July 1987 and july 1993, 498 patients were admitted to Keimyung University Dongsan Hospital with community acquired pneumonia, and 77 of them received intensive care. Of the 77 patients, 10 patients died. We reviewed medical records of these patients. Results: 1) The mean age of the patients was 56.2 years(range, 25 to 75 years). There were 7 men and 3 women. Seven patients(70%) were older than 60years of age. 2) The clinical features on admission were as follows: tachypnca, hypoxemia, mental change, cyanosis, leukopenia, leukocytosis, azotemia, hypotension, hypoalbuminemia in order of frequency. Three patients had one abnormal physical finding, 3 patients had 2, 2 patients had 3, and 2 patients had none of these abnormal physical findings. All patients had at least one of the abnormal laboratory findings. 3) A potential bacterial pathogen was isolated in sputum culture from 2 patients. One was E.coli, the other Enterobacter species. Sputum stain were positive in eight cases (G(+)cocci in six, G(+) cocci and G(-)bacilli in two). 4) Features of respiratory failure were the main reasons for ICU transfer, but two patients were transferred only following a cardiac or respiratory arrest in the general ward. 5) The mean of 2.7 different antibiotics were given to the patients. The aminoglycoside and first generation cephalosporin were the most frequently prescribed antibiotics, followed by the third generation cephalosporin and vancomycin. The most frequently prescribed antibiotics combination was a 1st generation cephalosporin plus an aminoglycoside. 6) Seven patients death(70%) occured after admission within the first five days, and a mean duration of hospitaliztion was 11.2 days. Conclusion: As the results show most death occured within the first five days after admission and aged patients; consequently, an aggressive intensive treatment should be provided early to the patients with severe community acquired pneumonia, and we should pay more attention to the aged patients.

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The Role and Significance of Biomarker for Plasma G-CSF in Patients with Primary Lung Cancer (원발성 폐암에서 혈장 과립구 자극인자의 암표지자로서의 역할과 의의)

  • Song, Jung Sub;Kim, So Young;Jo, Hyang Jeong;Lee, Kang Kyoo;Shin, Jeong Hyun;Shin, Seong Nam;Kim, Dong;Park, Seong Hoon;Lee, Young Jin;Ko, Chang Bo;Lee, Mi Kung;Choi, Soon Ho;Jeong, Jong Hoon;Park, Jung Hyun;Kim, Hui Jung;Kim, Hak Ryul;Jeong, Eun Taik;Yang, Sei Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.66 no.6
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    • pp.444-450
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    • 2009
  • Background: Biomarkers for cancer have several potential clinical uses, including the following: early cancer detection, monitoring for recurrence prognostication, and risk stratification. However, no biomarker has been shown to have adequate sensitivity and specificity. Many investigators have tried to validate biomarkers for the early detection and recurrence of lung cancer. To evaluate plasma G-CSF as such a biomarker, protein levels were measured and were found to correlate with the clinicopathological features of primary lung tumors. Methods: Between December 2006 and May 2008, 100 patients with histologically-validated primary lung cancer were enrolled into this study. To serve as controls, 127 healthy volunteers were enrolled into this study. Plasma G-CSF levels were measured in lung cancer patients using the sandwich ELISA system (R & D inc.) prior to treatment. Results: The mean plasma G-CSF levels were 12.2$\pm$0.3 pg/mL and 46.0$\pm$3.8 pg/mL (mean$\pm$SE) in the normal and in the cancer groups, respectively. In addition, plasma G-CSF levels were higher in patients with early lung cancer than in healthy volunteers (p<.001). Plasma G-CSF levels were higher in patients who were under 65 years old or smokers. Within the cancer group, plasma G-CSF levels were higher in patients with non small cell lung cancer than in patients with small cell lung cancer (p<.05). Overall, plasma G-CSF levels were shown to increase dependent upon the type of lung cancer diagnsosed. In the order from highest to lowest, the levels of plasma G-CSF tended to decrease in the following order: large cell carcinoma, squamous cell carcinoma, adenocarcinoma, and bronchioloalveolar carcinoma. Plasma G-CSF levels tended to be higher in patients with advanced TNM stage than in localized TNM stage (I, II

The Effects of Psychological Contract Violation on OS User's Betrayal Behaviors: Window XP Technical Support Ending Case (심리적 계약 위반이 OS이용자의 배신 행동에 미치는 영향: 윈도우 XP 기술적 지원서비스 중단 사례)

  • Lee, Un-Kon
    • Asia pacific journal of information systems
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    • v.24 no.3
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    • pp.325-344
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    • 2014
  • Technical support of Window XP ended in March, 8, 2014, and it makes OS(Operating System) users fall in a state of confusion. Sudden decision making of OS upgrade and replacement is not a simple problem. Firms need to change the long term capacity plan in enterprise IS management, but they are pressed for time and cost to complete it. Individuals can not help selecting the second best plan, because the following OSs of Window XP are below expectations in performances, new PC sales as the opportunities of OS upgrade decrease, and the potential risk of OS technical support ending had not announced to OS users at the point of purchase. Microsoft as the OS vendors had not presented precaution or remedy for this confusion. Rather, Microsoft announced that the technical support of the other following OSs of Wndow XP such as Window 7 would ended in two years. This conflict between OS vendor and OS users could not happen in one time, but could recur in recent future. Although studies on the ways of OS user protection policy would be needed to escape from this conflict, few prior studies had conducted this issue. This study had challenge to cautiously investigate in such OS user's reactions as the confirmation with OS user's expectation in the point of purchase, three types of justice perception on the treatment of OS vendor, psychological contract violation, satisfaction and the other betrayal behavioral intention in the case of Window XP technical support ending. By adopting the justice perception on this research, and by empirically validating the impact on OS user's reactions, I could suggest the direction of establishing OS user protection policy of OS vendor. Based on the expectation-confirmation theory, the theory of justice, literatures about psychological contract violation, and studies about consumer betrayal behaviors in the perspective of Herzberg(1968)'s dual factor theory, I developed the research model and hypothesis. Expectation-confirmation theory explain that consumers had expectation on the performance of product in the point of sale, and they could satisfied with their purchase behaviors, when the expectation could have confirmed in the point of consumption. The theory of justice in social exchange argues that treatee could be willing to accept the treatment by treater when the three types of justice as distributive, procedural, and interactional justice could be established in treatment. Literatures about psychological contract violation in human behaviors explains that contracter in a side could have the implied contract (also called 'psychological contract') which the contracter in the other side would sincerely execute the contract, and that they are willing to do vengeance behaviors when their contract had unfairly been broken. When the psychological contract of consumers had been broken, consumers feel distrust with the vendors and are willing to decrease such beneficial attitude and behavior as satisfaction, loyalty and repurchase intention. At the same time, consumers feel betrayal and are willing to increase such retributive attitude and behavior as negative word-of-mouth, complain to the vendors, complain to the third parties for consumer protection. We conducted a scenario survey in order to validate our research model at March, 2013, when is the point of news released firstly and when is the point of one year before the acture Window XP technical support ending. We collected the valid data from 238 voluntary participants who are the OS users but had not yet exposed the news of Window OSs technical support ending schedule. The subject had been allocated into two groups and one of two groups had been exposed this news. The data had been analyzed by the MANOVA and PLS. MANOVA results indicate that the OSs technical support ending could significantly decrease all three types of justice perception. PLS results indicated that it could significantly increase psychological contract violation and that this increased psychological contract violation could significantly reduce the trust and increase the perceived betrayal. Then, it could significantly reduce satisfaction, loyalty, and repurchase intention, and it also could significantly increase negative word-of-month intention, complain to the vendor intention, and complain to the third party intention. All hypothesis had been significantly approved. Consequently, OS users feel that the OSs technical support ending is not natural value added service ending, but the violation of the core OS purchase contract, that it could be the posteriori prohibition of OS user's OS usage right, and that it could induce the psychological contract violation of OS users. This study would contributions to introduce the psychological contract violation of the OS users from the OSs technical support ending in IS field, to introduce three types of justice as the antecedents of psychological contract violation, and to empirically validate the impact of psychological contract violation both on the beneficial and retributive behavioral intentions of OS users. For practice, the results of this study could contribute to make more comprehensive OS user protection policy and consumer relationship management practices of OS vendor.