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A Feasibility Study on Thermal Energy Resource in Deep Ocean Water (해양심층수 에너지자원 이용 타당성 분석 연구)

  • Kim, Jeong-Hyop;Kim, Gwang-Tae;Park, Se-Hun;Oh, Wee-Yeong;Kim, Hyeon-Ju
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.1
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    • pp.9-18
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    • 2012
  • Annual power consumption of our country is positioned in the upper percentile in the world, and because the proportion of fossil power generation is high, which ranks the 10th $CO_2$ emission country. In this regard, government has established and is implementing the National Energy Basic Plan to realize to get out of fossilization in energy supply while focusing on securing the technology for renewable energy as well as its commercialization in order to reduce greenhouse gas. Resource recovery technology for deep seawater thermal energy which is one of renewable energies is newly getting attention domestically as well as in overseas for securing resources and environmental improvement as a core technology for multilateral use of marine resources for low carbon and green growth. Economic feasibility analysis was conducted for the research and development as follows on the use of ocean thermal energy conversion and seawater air conditioning. First, in the case of power generation using deep seawater and warm discharge water from ocean thermal energy conversion plant of 1MW level, it is judged that the economic feasibility is insufficient but the feasibility will be significantly improved if we consider not only power generation but also drinking water and certified emission reduction by developing the power plant to the size for commercialization. Second, the economic feasibility for the use of deep seawater as air conditioning for the power plant of 1,000RT level turned out to be very good. Especially, when we consider certified emission reduction, it will be possible to secure sufficient economic feasibility. When we use it in connection with ocean thermal energy conversion, water conversion and agricultural and fishery use, it is judged that economic ripple effect will be significant and therefore it will be necessary to conduct research and development for early commercialization, distribution and diffusion of deep seawater energy.

Cost-Benefit Analysis on Rubella Vaccination Policy (풍진 예방접종사업의 비용-편익분석)

  • Shin, Young-Jeon;Choi, Bo-Youl;Park, Hung-Bae;Moon, Ok-Ryun;Yoon, Bae-Joong
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.2 s.46
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    • pp.337-365
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    • 1994
  • Rubella is a viral disease with mild constitutional symptoms and generalized rashes. In childhood, it is an inconsequential illness, but when it occurs during early pregnant period, there are significant risks of heart defects, cataract, mental retardation to the fetus. The series of congenital defects induced by rubella is called 'congenital rubella syndrome'. Many research have been performed to find out more effective prevention program on rubella. The objectives of this study are, first, to calculate the incidence rate of acute rubella infection and congenital rubella syndrome in Korea, second, to evaluate economic efficiency of several rubella vaccination policies and to offer data for the most reasonable decision on vaccination policy. Study populations are 663,312 children of one year-old in 1992. The author has performed cost-benefit analyses according to the three vaccination policies-U.S.A.'s. U.K.'s and Sweden's. In this Study, the author got the incidence rate of acute rubella infection using the catalytic model. In the meantime, the author used 50 per 100,000 live births as the incidence rate of congenital rubella syndrome. The discount rate used in this study was 5 percent per annum. The sensitivity analyses were done with different discount rates (4%, 7%) and different incidence rate of congenital rubella syndrome (10,100 per 100,000 live births) : The study results are as follows: 1. Without vaccination, lifetime expenditures per patient for acute rubella infeciton amount to 14,822 won and the total expenditures to about 3.1 billion won. Meanwhile, lifetime expenditures per patient for congenital rubella syndrome amount to about 91 million won and the total expenditures to about 16.3 billion won without vaccination. 2. The cost of vaccination for a child of one year old was 2,322 won and the total cost for the one year old children was about 1.5 billion won (American style). The cost for vaccination of female children at fifteen was about 339 million won (Birtish style). And the cost of vaccination at one for both sex and female children at fifteen was about 1.9 billion won (Swedish style). 3. The benefit to cost ratios of vaccination of female children at fifteen that is the british mode of rubella vaccination, was 60.0 at the level of 80% population coverage and 48.6 at 100% coverage. It shows much higher benefit to cost ratio than those of the other two vaccination policies. 4. Both net benefits of vaccination at one (American style) and that of vaccinations at one and fifteen (Swedish style) range from about 17.0 billion to 17.8 billion won, those were larger than that of vaccinations of female children at fifteen (Birtish style, about 16.0 billion). 5. In marginal cost-benefit analysis of only additional program of revaccination, the benefit to cost ratios were 3.6 (80% coverage rate) or 0.6 (100% coverage rate). It implies that additional program was less efficient or inefficient. 6. In sensitivity analysis with different discount rates(4% or 7%) and different incidence rates of congenital rubella syndrome (10 or 100 per 100,000 live births), the benefit to cost ratios has fluctuated in wide range. However, all the ratios of vaccination of female children at fifteen were higher than those of the others. Even under the most conservative assumption, the benefit to cost ratios of all the rubella vaccination policies were higher than 3.3. In conclusion, all the rubella vaccination policies found to be cost-effective and particularly the vaccination of female children at fifteen was strongly recommended.

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Development of a Dose Calibration Program for Various Dosimetry Protocols in High Energy Photon Beams (고 에너지 광자선의 표준측정법에 대한 선량 교정 프로그램 개발)

  • Shin Dong Oh;Park Sung Yong;Ji Young Hoon;Lee Chang Geon;Suh Tae Suk;Kwon Soo IL;Ahn Hee Kyung;Kang Jin Oh;Hong Seong Eon
    • Radiation Oncology Journal
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    • v.20 no.4
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    • pp.381-390
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    • 2002
  • Purpose : To develop a dose calibration program for the IAEA TRS-277 and AAPM TG-21, based on the air kerma calibration factor (or the cavity-gas calibration factor), as well as for the IAEA TRS-398 and the AAPM TG-51, based on the absorbed dose to water calibration factor, so as to avoid the unwanted error associated with these calculation procedures. Materials and Methods : Currently, the most widely used dosimetry Protocols of high energy photon beams are the air kerma calibration factor based on the IAEA TRS-277 and the AAPM TG-21. However, this has somewhat complex formalism and limitations for the improvement of the accuracy due to uncertainties of the physical quantities. Recently, the IAEA and the AAPM published the absorbed dose to water calibration factor based, on the IAEA TRS-398 and the AAPM TG-51. The formalism and physical parameters were strictly applied to these four dose calibration programs. The tables and graphs of physical data and the information for ion chambers were numericalized for their incorporation into a database. These programs were developed user to be friendly, with the Visual $C^{++}$ language for their ease of use in a Windows environment according to the recommendation of each protocols. Results : The dose calibration programs for the high energy photon beams, developed for the four protocols, allow the input of informations about a dosimetry system, the characteristics of the beam quality, the measurement conditions and dosimetry results, to enable the minimization of any inter-user variations and errors, during the calculation procedure. Also, it was possible to compare the absorbed dose to water data of the four different protocols at a single reference points. Conclusion : Since this program expressed information in numerical and data-based forms for the physical parameter tables, graphs and of the ion chambers, the error associated with the procedures and different user could be solved. It was possible to analyze and compare the major difference for each dosimetry protocol, since the program was designed to be user friendly and to accurately calculate the correction factors and absorbed dose. It is expected that accurate dose calculations in high energy photon beams can be made by the users for selecting and performing the appropriate dosimetry protocol.

Changes in Weed Occurrence and Dominance Influenced by Seeding Dates in Water Seeded Rice Paddy under No-tillage Condition (벼 무경운(無耕耘) 담수표면산파재배시(湛水表面散播栽培時) 파종시기(播種時期)에 따른 잡초(雜草) 발생양상(發生樣相) 및 우점도(優點度) 변이(變異))

  • Kwon, O.D.;Guh, J.O.;Shin, H.R.;Park, T.D.
    • Korean Journal of Weed Science
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    • v.18 no.3
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    • pp.179-185
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    • 1998
  • This study was conducted to investigate changes in weed occurrence and dominance as affected by seeding dates in water seeded rice paddy under field following two years of no-tillage condition. The pre-emergence weeds in no-tillage paddy were controlled by glyphosate application at 7 days before seeding. The rice seeds were seeded on April 20, May 10 and May 30, respectively with 40kg/ha of seeding rate. The weed species in the paddy occurred included three species (Echinochloa cursgalli, Aneilma keisak, Ottelia alismoides) of annual weed, one species (Alopecurus aequalis) of biennial weed and five species (Eleocharis kuroguwai, Leersia japonica, Sagittaria pygmaea, Sagittaria trifolia, Potamogeton distinctus) of perennial weed respectively. Aneilma keisak was found to be dorminant on April 20 and May 10 but Eleocharis kuroguwai on May 30 based on number of weeds. The number and dry weight of weeds occurred were higher on May 10 as compared to in other seeding dates, while proportion of perennial weeds increased as the seeding date was delayed. In particular, weed dorminance varied marketly with seeding date. The Simpson's indices were 0.736 on April 20, 0.261 on May 10 and 0.281 on May 30, respectively.

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Growth inhibition of hydrotrope-combined copper against Microcystis aeruginosa and evaluation of its toxicity (Microcystis aeruginosa에 대한 hydrotrope-combined copper의 생장억제 및 독성 평가)

  • Park, Se-Keun;Ji, Jun-Gu;Jang, Hee Jung;Kim, Yeong-Kwan;Oh, Young-Sook;Choi, Sung-Chan
    • Korean Journal of Microbiology
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    • v.51 no.1
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    • pp.7-13
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    • 2015
  • Hydrotrope-combined copper (HCC) is a copper ($Cu^{2+}$)-based algicide, which is combined with a hydrotrope that keeps copper ion in solution to improve performance. This study assessed the growth inhibition effect of HCC against Microcystis aeruginosa which is one of the most common toxic cyanobacterium in eutrophic freshwater environment. Various HCC doses, ranging from 5.5 to $550{\mu}g/L$ as $Cu^{2+}$, were applied to either BG-11 or 1/4 diluted medium with low- or high-inoculum density of M. aeruginosa. Growth inhibition was monitored based on a decrease in chlorophyll-a content in culture medium during the incubation. Results showed that HCC significantly inhibited the growth of M. aeruginosa in a dose-dependent manner. In case of 1/4 diluted BG-11 medium, HCC dose as low as $5.5{\mu}g$ $Cu^{2+}/L$ completely inhibited the production of chlorophyll-a by M. aeruginosa. It was found that HCC did not induce any significant release of microcystin-LR from M. aeruginosa. Acute toxicity of HCC was tested using Daphnia magna, and the 24-h $EC_{50}$ value was 0.30 mg/L as $Cu^{2+}$ which was much higher than the actual inhibition dose. Ames test was performed using Salmonella enterica serovar Typhimurium TA100, and HCC showed no increase in the number of revertant colonies. The result suggested that HCC does not have any mutagenic potential in the aquatic environment. In addition, no genotoxic effect of HCC was also confirmed based on the SOS ChromoTest using Escherichia coli PQ37. Therefore, HCC could be used as a relatively safe and effective pre- and post-treatment agent to control hazardous algal blooming in aquatic environments.

Potential Reproductive Toxicity Study of p53 Expressing Adenoviral Vector in Mice (아데노바이러스 유전자치료벡터의 생식독성 연구)

  • Rhee, Gyu-Seek;Kwack, Seung-Jun;Kim, Soon-Sun;Lee, Rhee-Da;Seok, Ji-Hyun;Chae, Soo-Young;Chung, Soo-Youn;Kim, Seung-Hee;Lee, Seung-Hoon;Park, Kui-Lea
    • Korean Journal of Microbiology
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    • v.43 no.3
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    • pp.151-158
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    • 2007
  • The possibility of inadvertent introduction of therapeutic gene expressing viral vectors has raised safety concerns about germ-line infection. Particularly, for indications such as prostate cancer and ovarian cancer, the proximity of the point of viral administration to organs of the reproductive system raises concerns regarding inadvertent germ-line transmission of genes carried by the virus vector. To evaluate the safety of in vivo adenovirus mediated gene transfer, we explored the biodistribution, persistance and potential germ-line transmission of p53-expressing adenovirus (Ad-CMV-p53). Both male and female Balb/c mice were injected with $1{\times}10^9$ PFU of Ad-CMV-p53. The PCR analysis showed that there were detectable vector sequences in liver, kidney, spleen, seminal vesicle, epididymis, prostate, ovary, and uterus. The RT-PCR analysis for detecting inserted gene, p53 showed that Ad-CMV-p53 viral RNA were present in spleen, prostate and ovary. Direct injected male and female mice of adenovirus vector into testis and ovary were mated and their of offspring were evaluated for germ-line transmission of the adenoviral vector. The PCR and RT-PCR analysis showed no evidence of germline transmission, although vector sequences were detected in DNA extracted from gonadal tissues. Real-time PCR result confirmed a significant decrease of adenovirus in gonad tissues 1 week after injection. We have also analysed the cell specific localization of viral DNA in gonad tissues by using in-situ PCR. Positive signals were detected in interstitial tissue but not in seminiferous tubule in sperm. In the case of ovary, adenovirus signal were localized to the stromal tissue, but no follicular signals were observed. Together, these data provide strong evidence that the risk of the Inadvertent germ-line transmission of vector sequences following intraperitoneal or direct injection into genito-urinary system of adenovirus is extremely low.

Spaciotemporal Distributions of PM10 Concentration and Their Correlation with Local Temperature Changes : a Case Study of Busan Metropolitan City (PM10 농도의 시공간적 분포 특징과 국지적 기온 변화 간의 상관관계: 부산광역시 사례 분석)

  • Park, Sunyurp
    • Journal of the Korean association of regional geographers
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    • v.23 no.1
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    • pp.151-167
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    • 2017
  • The main objective of this study was to investigate the climatic impact of $PM_{10}$ concentration on the temperature change pattern in Busan Metropolitan City(BMC), Korea during 2001~2015. Mean $PM_{10}$ concentration of BMC has gradually declined over the past 15 years. While the highest $PM_{10}$ concentration was observed in spring followed by winter, summer, and fall on average, the seasonal variations of $PM_{10}$ concentration differed from place to place within the city. Frequency analysis showed that the most frequently observed $PM_{10}$ concentration ranged from $20{\mu}g/m^3$ to $60{\mu}g/m^3$, which accounted for 64.6% of all daily observations. Overall, the west-high and east-low pattern of $PM_{10}$ concentration was relatively strong during the winter when the effect of yellow-dust events on the air quality was weak. Comparative analyses between $PM_{10}$ concentration and monthly temperature slope derived from generalized temperature curves indicated that the decreasing trend of $PM_{10}$ concentration was associated with increases of annual temperature range, and $PM_{10}$ concentration had a negative relationship with the temperature slope of warming months. Overall, $PM_{10}$ concentration had a weak correlation with the annual mean temperature, but it had a significant, positive correlation with the winter season, which had a dominant influence on the annual mean temperature. In terms of energy budget, it has been known that the change in $PM_{10}$ concentration contributes to the warming or cooling effect by affecting the radiative forcing due to the reflection and absorption of radiant energy. The correlation between $PM_{10}$ concentration and temperature changes in the study area was not seasonally and spatially consistent, and its significance was statistically limited partly due to the number of observations and the lack of potential socioeconomic factors relevant to urban air quality.

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Sodium Intakes of Korean Adults with 24-hour Urine Analysis and Dish Frequency Questionnaire and Comparison of Sodium Intakes According to the Regional Area and Dish Group (24시간 소변분석과 음식섭취빈도지를 사용한 우리나라 성인들의 나트륨 섭취량과 지역별, 음식군별 나트륨 섭취량의 비교)

  • Son, Sook-Mee;Park, Young-Sook;Lim, Hwa-Jae;Kim, Sook-Bae;Jeong, Yeon-Seon
    • Korean Journal of Community Nutrition
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    • v.12 no.5
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    • pp.545-558
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    • 2007
  • This study was performed to assess the sodium intakes of Korean adults using a 24-hr urine analysis and dish frequency questionnaire (DFQ) according to each dish group and the regional area. The subjects of this study were comprised of 522 adults (male : 267, female : 285), aged 20-59yr residing in the metropolitan area (N=200), Chungcheng-Do (N=117), Jeolla-Do(N=117), and Gueongsang-Do provinces (N=118). The subjects were recruited from the residents who once participated or are participating in the various health programs offered by the public health center. The number of subjects who completed the 24-hr urine collection was 205 (male : 110, female : 95). The mean age and BMI of the subjects were $39.0{\pm}$11.7y and $23.1{\pm}2.9 kg/m^2$, respectively. The mean systolic and diastolic blood pressure was $119.5{\pm}15.4 mmHg$, and $77.1{\pm}11.1 mmHg$, respectively. Eighteen percent of the subjects responded that they are currently smoking, 36% drinking and 50.4% exercising. Twenty point six percent of the subjects were assessed as having hypertension according to their systolic or diastolic blood pressure($SBP{\ge}140mmHg$ or $DBP{\ge}90mmHg$) measurements in the present study. Salt intake of the subjects estimated with 24-hr sodium excretion was 12.7g/d (male : 13.4g/d, female : 12.1g/d) based on the sodium excretion rate as 82%. Salt intake estimated with DFQ was 14.7g/d (male : 16.2g/d, female : 13.4g/d), 2 g more than the salt intake estimated with 24-hr urine analysis. The four dish groups that contributed most to the sodium intake in order were kimchi (11571.4mg), soup and stew (1260.5mg), fish and shellfish(706.3mg) and noodle and ramyeon(644.3mg). Salt intake estimated with DFQ was the highest in the subjects of Gueongsang-Do(17.0g/d), second highest Chungcheong-Do (16.4g/d) and the lowest in the metropolitan area (13.0g/d). Subjects of Gueongsang-Do showed the highest sodium intakes in most of the dish group, whereas subjects of the metropolitan area showed the lowest. Residents of Chungcheong-Do revealed the highest sodium intake with kimchi and of Jeolla-Do the higher sodium intake with main dish (meat, fish and beans). The highest salt percentage of kimchi ($3.0{\pm}0.8%$) and soybean paste ($14.5{\pm}5.1%$) were observed in Gueongsang-Do, whereas individuals of the metropolitan area were observed as having kimchi ($1.6{\pm}0.5%$) and soybean paste ($7.4{\pm}1.6%$) with the lowest salt percenage. Men were observed as having more salty kimchi ($2.4{\pm}0.1%$) than women ($2.1{\pm}0.1%$).

Effects of Deer Antler on the Regeneration of Peripheral Nerves; About Sprout Formation of Experimentally Transected Sciatic Nerves in Rat (말초신경의 재생에 대한 녹용의 효과; 랫드에서 실험적 절단 좌골신경의 Sprout 형성에 관해)

  • Chang, Byung-Joon;Cho, Ik-Hyun;Choi, Hye-Young;Won, Hui-Young;Park, Chang-Hyun;Bae, Chun-Sik;Choe, Nong-Hoon
    • Applied Microscopy
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    • v.32 no.1
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    • pp.67-80
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    • 2002
  • This study was carried out to investigate the effects of deer antler extract on the regeneration of peripheral nerves. Sprague-Dawley male rats weighing about 300 gm were fed deer antler extract for 1, 2, and 3 weeks per oral (1.5 ml/100 gm B.W.), respectively, once a day and transected both sides of sciatic nerve of each leg. After keeping for 6 hours, sciatic nerves taken from proximal part of transected region were treated with conventional transmission electron microscopical method and then observed with electron microscope. The results obtained were summarized as follows; 1. Sciatic nerves of normal control group were not showing any sprouts and electron dense axolemmal projections were frequently observed. 2. Sciatic nerves of saline treated groups were showing axonal sprouts at the nodes of Ranvier. The length of them was usually short, and numerous vesicles, vacuoles and organelles including neurofilament were contained. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 29 (29%) in 1 week treated group, 32 (32%) in 2 weeks treated group, and 30 (30%) in 3 weeks treated group, respectively. 3. Sciatic nerves of deer antler treated groups were showing axonal sprouts at the node of Ranvier as well. Although most of the sprouts were short, some sprouts of 2 weeks and 3 weeks treated groups were quite long. Sprouts usually contained numerous vesicles, vacuoles and cell organelles such as neurofilaments and mitochondria. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 38 (38%) in 1 week treated group, 46 (46%) in 2 weeks treated group, and 48 (48%) in 3 weeks treated group respectively. The results described above explain pretreatment of deer antler extract improves the sprout formation of transected sciatic nerves, and then it suggests deer antler may be effective for the regeneration of peripheral nerves.

A Performance Comparison of the Mobile Agent Model with the Client-Server Model under Security Conditions (보안 서비스를 고려한 이동 에이전트 모델과 클라이언트-서버 모델의 성능 비교)

  • Han, Seung-Wan;Jeong, Ki-Moon;Park, Seung-Bae;Lim, Hyeong-Seok
    • Journal of KIISE:Information Networking
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    • v.29 no.3
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    • pp.286-298
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    • 2002
  • The Remote Procedure Call(RPC) has been traditionally used for Inter Process Communication(IPC) among precesses in distributed computing environment. As distributed applications have been complicated more and more, the Mobile Agent paradigm for IPC is emerged. Because there are some paradigms for IPC, researches to evaluate and compare the performance of each paradigm are issued recently. But the performance models used in the previous research did not reflect real distributed computing environment correctly, because they did not consider the evacuation elements for providing security services. Since real distributed environment is open, it is very vulnerable to a variety of attacks. In order to execute applications securely in distributed computing environment, security services which protect applications and information against the attacks must be considered. In this paper, we evaluate and compare the performance of the Remote Procedure Call with that of the Mobile Agent in IPC paradigms. We examine security services to execute applications securely, and propose new performance models considering those services. We design performance models, which describe information retrieval system through N database services, using Petri Net. We compare the performance of two paradigms by assigning numerical values to parameters and measuring the execution time of two paradigms. In this paper, the comparison of two performance models with security services for secure communication shows the results that the execution time of the Remote Procedure Call performance model is sharply increased because of many communications with the high cryptography mechanism between hosts, and that the execution time of the Mobile Agent model is gradually increased because the Mobile Agent paradigm can reduce the quantity of the communications between hosts.