• Asia pacific journal of information systems
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• v.22 no.3
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• pp.75-97
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• 2012

Knowledge residing in the heads of employees has always been regarded as one of the most critical resources within a firm. However, many tries to facilitate knowledge transfer among employees has been unsuccessful because of the motivational and cognitive problems between the knowledge source and the recipient. Social capital, which is defined as "the sum of the actual and potential resources embedded within, available through, derived from the network of relationships possessed by an individual or social unit [Nahapiet and Ghoshal, 1998]," is suggested to resolve these motivational and cognitive problems of knowledge transfer. In Social capital theory, there are two research streams. One insists that social capital strengthens group solidarity and brings up cooperative behaviors among group members, such as voluntary help to colleagues. Therefore, social capital can motivate an expert to transfer his/her knowledge to a colleague in need without any direct reward. The other stream insists that social capital provides an access to various resources that the owner of social capital doesn't possess directly. In knowledge transfer context, an employee with social capital can access and learn much knowledge from his/her colleagues. Therefore, social capital provides benefits to both the knowledge source and the recipient in different ways. However, prior research on knowledge transfer and social capital is mostly limited to either of the research stream of social capital and covered only the knowledge source's or the knowledge recipient's perspective. Social network theory which focuses on the structural dimension of social capital provides clear explanation about the in-depth mechanisms of social capital's two different benefits. 'Strong tie' builds up identification, trust, and emotional attachment between the knowledge source and the recipient; therefore, it motivates the knowledge source to transfer his/her knowledge to the recipient. On the other hand, 'weak tie' easily expands to 'diverse' knowledge sources because it does not take much effort to manage. Therefore, the real value of 'weak tie' comes from the 'diverse network structure,' not the 'weak tie' itself. It implies that the two different perspectives on strength of ties can co-exist. For example, an extroverted employee can manage many 'strong' ties with 'various' colleagues. In this regards, the individual-level structure of one's relationships as well as the dyadic-level relationship should be considered together to provide a holistic view of social capital. In addition, interaction effect between individual-level characteristics and dyadic-level characteristics can be examined, too. Based on these arguments, this study has following research questions. (1) How does the social capital of the knowledge source and the recipient influence knowledge transfer respectively? (2) How does the strength of ties between the knowledge source and the recipient influence knowledge transfer? (3) How does the social capital of the knowledge source and the recipient influence the effect of the strength of ties between the knowledge source and the recipient on knowledge transfer? Based on Social capital theory and Social network theory, a multi-level research model is developed to consider both the individual-level social capital of the knowledge source and the recipient and the dyadic-level strength of relationship between the knowledge source and the recipient. 'Cross-classified random effect model,' one of the multi-level analysis methods, is adopted to analyze the survey responses from 337 R&D employees. The results of analysis provide several findings. First, among three dimensions of the knowledge source's social capital, network centrality (i.e., structural dimension) shows the significant direct effect on knowledge transfer. On the other hand, the knowledge recipient's network centrality is not influential. Instead, it strengthens the influence of the strength of ties between the knowledge source and the recipient on knowledge transfer. It means that the knowledge source's network centrality does not directly increase knowledge transfer. Instead, by providing access to various knowledge sources, the network centrality provides only the context where the strong tie between the knowledge source and the recipient leads to effective knowledge transfer. In short, network centrality has indirect effect on knowledge transfer from the knowledge recipient's perspective, while it has direct effect from the knowledge source's perspective. This is the most important contribution of this research. In addition, contrary to the research hypothesis, company tenure of the knowledge recipient negatively influences knowledge transfer. It means that experienced employees do not look for new knowledge and stick to their own knowledge. This is also an interesting result. One of the possible reasons is the hierarchical culture of Korea, such as a fear of losing face in front of subordinates. In a research methodology perspective, multi-level analysis adopted in this study seems to be very promising in management research area which has a multi-level data structure, such as employee-team-department-company. In addition, social network analysis is also a promising research approach with an exploding availability of online social network data.

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.1-15
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• 1993

This research aims to investigate some respects of chemical weathering processes, espcially the amount of solute leaching, formation of clay minerals, and the chemical weathering rate of granite rocks under present climatic conditions. For this purpose, I investigated geochemical mass balance in a small catchment and the mineralogical composition of weathered bedrocks including clay mineral assemblages at four res-pective sites along one slope. The geochemical mass blance for major elements of rock forming minerals was calculated from precipitation and streamwater data which are measured every week for one year. The study area is a climatically and litholo-gically homogeneous small catchment($3.62Km^2$)in Anyang-shi, Kyounggi-do, Korea. The be-drock of this area id Anyang Granite which is composed of coarse-giained, pink-colored miner-als. Main rock forming minerals are quartz, K-Feldspar, albite, and muscovite. One of the chracteristics of this granite rock is that its amount of Ca and Mg is much lower than other granite rock. The leaching pattern in the weathering profiles is in close reltion to the geochemical mass balance. Therefore the removal or accumulation of dissolved materials shows weathering patterns of granite in the Korean peninsula. Oversupplied ions into the drainage basin were $H^+$, $K^+$, Fe, and Mn, whereas $Na^2+$, $Mg^2+$, $Ca^2+$, Si, Al and $HCO-3^{-}$ were removed from the basin by the stream. The consumption of hydrogen ion in the catchment implies the hydrolysis of minerals. The surplus of $K^+$ reflects that vegetation is in the aggravation stage, and the nutrient cycle of the forest in study area did not reach a stable state. And it can be also presumed that the accumulation of $K^+$ in the top soil is related to the surplus of $K^+$. Oversupplied Fe and Mn were presumed to accumulate in soil by forming metallic oxide and hydroxide. In the opposite, the removal of $Na^+$, Si, Al resulted from the chemical weathering of albite and biotite, and the amount of removal of $Na^+$, Si, Al reflected the weathering rate of the bedrock. But $Ca^2+$ and $Mg^2+$ in stream water were contaminated by the scattered calcareous structures over the surface. Kaolinite is a stable clay mineral under the present environment by the thermodynamical analysis of the hydrogeochemical data and Tardy's Re value. But this result was quite different from the real assemblage of clay miner-als in soil and weathered bedrock. This differ-ence can be explained by the microenvironment in the weathering profile and the seasonal variation of climatic factors. There are different clay forming environments in the stydy area and these differences originate from the seasonal variation of climate, especially the flushing rate in the weathering profile. As it can be known from the results of the analysis of thermodynamic stability and characteristics of geochemical mas balance, the climate during winter and fall, when it is characterized by the low flushing rate and high solute influx, shows the environmental characteristics to from 2:1 clay minerals, such as illite, smectite, vermiculite and mixed layer clay minerals which are formed by neoformation or transformation from the primary or secondary minerals. During the summer and spring periods, kaoli-nite is a stable forming mineral. However it should consider that the other clay minerals can transformed into kaolinite or other clay minerals, because these periods have a high flushing rte and temperature. Materials which are directly regulated by chemical weathering in the weathered bedrock are $Na^+$, Si, and Al. The leaching of Al is, however, highly restricted and used to form a clay mineral, and that of Si falls under the same category. $Na^+$ is not taked up by growing veget ation, and fixed in the weathering profile by forming secondary minerals. Therefore the budget of $Na^+$ is a good indicator for the chemical weathering rate in the study area. The amount of chemical weathering of granite rocks was about 31.31g/$m^2+$/year based on $Na^+$ estimation.

• Journal of Global Scholars of Marketing Science
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• v.19 no.1
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• pp.9-21
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• 2009

Recently, the researches to explain Switching Behavior through Theory of Planned Behavior have been discovered. Many researches say that System factors of mobile telecommunication service(MTS) is positively associated with Switching Intention. But There is no difference of system factors between mobile telecommunication services because of IT technique Development. Thus, this study investigated whether switching cost and alternative's attractiveness influence switching intention concerning mobile telecommunication service by adopting Theory of Planned Behavior (TPB) as an underlying theoretical premise. The study also attempted to determine the moderating effects of personal innovativeness on switching intention. For these purposes the author has developed several hypotheses as follows: H-1. The switching cost of different MTS is associated with the attitude of MTS which is using. H-2. The switching cost of different MTS is associated with the subjective norm of MTS which is using. H-3. The switching cost of different MTS is associated with the perceived behavior control of MTS which is using. H-4. The alternative's attractiveness of different MTS is associated with the attitude of MTS which is using. H-5. The alternative's attractiveness of different MTS is associated with the subjective norm of MTS which is using. H-6. The alternative's attractiveness of different MTS is associated with the perceived behavior control of MTS which is using. H-7. The switching cost of different MTS is associated with the switching intention. H-8. The alternative's attractiveness of different MTS is associated with the switching intention. H-9. The attitude of MTS is associated with the switching intention. H-10. The subjective norm of MTS is associated with the switching intention. H-11. The perceived behavior control of MTS is associated with the switching intention. H-12. The personal innovativeness has been a moderating effects to switching intention. Data has been collected from 403 respondents for this study using a questionnaire method. The survey for the actual analysis of the research was done and analyzed with the customers who have an experience of using Mobile telecommunication service and the samples were selected among the middle and high school students who live in Seoul area, the university students who live in Seoul, Gyeonggi and Chungcheng Provinces, and the ordinary workers who are working in Seoul and Gyeonggi Province. The survey was done for 23 days from March 28, 2008 through April 12, 2008. The positive analysis was done with SPSS 12.0K statistics package and visual PLS program using the analysis techniques of frequency analysis, reliability analysis, correlation analysis and factor analysis. In addition, structural equation modeling was conducted using AMOS 5.0. The data was analyzed by frequency analysis using SPSS 12.0 and structural equation modeling using AMOS 5.0. The result of the overall model analysis is as follows: Chi-Square=378.306, d.f.=107, p-value=0.0, GFI=.904, AGFI= 0.863, IFI= 0.939, NFI= 0.917, RMSEA= 0.079, TLI= 0.922. The results of the overall model analysis were coherent. The following study results were revealed: First, switching cost was related positively to attitude, subjective norm and perceived behavior control, three components of TPB. Second, alternative's attractiveness was related negatively to subjective norm but positively to perceived behavior control. Third, switching cost and attitude was related negatively to switching intention, while perceived behavior control was related positively to switching intention. Finally, the study found the moderating effects of personal innovativeness on switching intention. Based on the results, the study offers marketing strategic implications for mobile telecommunication service industry.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.123-138
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• 2016

This study investigates intents of acquisitions in information technology industries. Mergers and acquisitions are a strategic decision at corporate-level and have been an important tool for a firm to grow. Plenty of firms in information technology industries have acquired startups to increase production efficiency, expand customer base, or improve quality over the last decades. For example, Google has made about 200 acquisitions since 2001, Cisco has acquired about 210 firms since 1993, Oracle has made about 125 acquisitions since 1994, and Microsoft has acquired about 200 firms since 1987. Although there have been many existing papers that theoretically study intents or motivations of acquisitions, there are limited papers that empirically investigate them mainly because it is challenging to measure and quantify intents of M&As. This study examines the intent of acquisitions by measuring specific intents for M&A transactions. Using our measures of acquisition intents, we compare the intents by four acquisition types: (1) the acquisition where a hardware firm acquires a hardware firm, (2) the acquisition where a hardware firm acquires a software/IT service firm, (3) the acquisition where a software/IT service firm acquires a hardware firm, and (4) the acquisition where a software /IT service firm acquires a software/IT service firm. We presume that there are difference in reasons why a hardware firm acquires another hardware firm, why a hardware firm acquires a software firm, why a software/IT service firm acquires a hardware firm, and why a software/IT service firm acquires another software/IT service firm. Using data of the M&As in US IT industries, we identified major intents of the M&As. The acquisition intents are identified based on the press release of M&A announcements and measured with four categories. First, an acquirer may have intents of cost saving in operations by sharing common resources between the acquirer and the target. The cost saving can accrue from economies of scope and scale. Second, an acquirer may have intents of product enhancement/development. Knowledge and skills transferred from the target may enable the acquirer to enhance the product quality or to expand product lines. Third, an acquirer may have intents of gain additional customer base to expand the market, to penetrate the market, or to enter a foreign market. Fourth, a firm may acquire a target with intents of expanding customer channels. By complementing existing channel to the customer, the firm can increase its revenue. Our results show that acquirers have had intents of cost saving more in acquisitions between hardware companies than in acquisitions between software companies. Hardware firms are more likely to acquire with intents of product enhancement or development than software firms. Overall, the intent of product enhancement/development is the most frequent intent in all of the four acquisition types, and the intent of customer base expansion is the second. We also analyze our data with the classification of production-side intents and customer-side intents, which is based on activities of the value chain of a firm. Intents of cost saving operations and those of product enhancement/development can be viewed as production-side intents and intents of customer base expansion and those of expanding customer channels can be viewed as customer-side intents. Our analysis shows that the ratio between the number of customer-side intents and that of production-side intents is higher in acquisitions where a software firm is an acquirer than in the acquisitions where a hardware firm is an acquirer. This study can contribute to IS literature. First, this study provides insights in understanding M&As in IT industries by answering for question of why an IT firm intends to another IT firm. Second, this study also provides distribution of acquisition intents for acquisition types.

• Asia pacific journal of information systems
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• v.20 no.3
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• pp.191-204
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• 2010

Recently, the CO2 emission and energy consumption have become critical global issues to decide the future of nations. Especially, the spread of IT products and the increased use of internet and web applications result in the energy consumption and CO2 emission of IT industry though information technologies drive global economic growth. EU, the United States, Japan and other developed countries are using IT related environmental regulations such as WEEE(Waste Electrical and Electronic Equipment), RoHS(Restriction of the use of Certain Hazardous Substance), REACH(Registration, Evaluation, Authorization and Restriction of CHemicals) and EuP(Energy using Product), and have established systematic green business/IT strategies to enhance the competitiveness of IT industry. For example, the Japan government proposed the "Green IT initiative" for being compatible with economic growth and environmental protection. Not only energy saving technologies but energy saving systems have been developed for accomplishing sustainable development. Korea's CO2 emission and energy consumption continuously have grown at comparatively high rates. They are related to its industrial structure depending on high energy-consuming industries such as iron and steel Industry, automotive industry, shipbuilding industry, semiconductor industry, and so on. In particular, export proportion of IT manufacturing is quite high in Korea. For example, the global market share of the semiconductor such as DRAM was about 80% in 2008. Accordingly, Korea needs to establish a systematic strategy to respond to the global environmental regulations and to maintain competitiveness in the IT industry. However, green competitiveness of Korea ranked 11th among 15 major countries and R&D budget for green technology is not large enough to develop energy-saving technologies for infrastructure and value chain of low-carbon society though that grows at high rates. Moreover, there are no concrete action plans in Korea. This research aims to deduce the priorities of the Korean green business/IT strategies to use multi attribute weighted average method. We selected a panel of 19 experts who work at the green business related firms such as HP, IBM, Fujitsu and so on, and selected six assessment indices such as the urgency of the technology development, the technology gap between Korea and the developed countries, the effect of import substitution, the spillover effect of technology, the market growth, and the export potential of the package or stand-alone products by existing literature review. We submitted questionnaires at approximately weekly intervals to them for priorities of the green business/IT strategies. The strategies broadly classify as follows. The first strategy which consists of the green business/IT policy and standardization, process and performance management and IT industry and legislative alignment relates to government's role in the green economy. The second strategy relates to IT to support environment sustainability such as the travel and ways of working management, printer output and recycling, intelligent building, printer rationalization and collaboration and connectivity. The last strategy relates to green IT systems, services and usage such as the data center consolidation and energy management, hardware recycle decommission, server and storage virtualization, device power management, and service supplier management. All the questionnaires were assessed via a five-point Likert scale ranging from "very little" to "very large." Our findings show that the IT to support environment sustainability is prior to the other strategies. In detail, the green business /IT policy and standardization is the most important in the government's role. The strategies of intelligent building and the travel and ways of working management are prior to the others for supporting environment sustainability. Finally, the strategies for the data center consolidation and energy management and server and storage virtualization have the huge influence for green IT systems, services and usage This research results the following implications. The amount of energy consumption and CO2 emissions of IT equipment including electrical business equipment will need to be clearly indicated in order to manage the effect of green business/IT strategy. And it is necessary to develop tools that measure the performance of green business/IT by each step. Additionally, intelligent building could grow up in energy-saving, growth of low carbon and related industries together. It is necessary to expand the affect of virtualization though adjusting and controlling the relationship between the management teams.

• Women's Health Nursing
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• v.1 no.2
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• pp.200-221
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• 1995

The confusion of the sense of value on sex is increasing because of the rapid change in social-cultural environment. Also due to a rise in the standard of living, the age of adolescence is getting lower, and so the second sexual marks appear to primary schoolers. At this time in the aspect of the education for the whole man, it's very important for primary schoolers to acquire right knowledge and desirable attitude on sex so that can overcome psychological instability caused by physical growth, be responsible for their behaviors and lead happy lives. This study was made to find out the effects of sex education for the primary schoolers' knowledge and attitude about sex. The study was designed as simulated control group pretest-posttest design, which only pretest was practiced to control group and after sex education only posttest was practiced to experimental group. The data was collected for 18 days from March 13, 1995 to March 31, 1995. The subjects of this study were 130 six-graders in a private primary school in seoul. The control group and experimental group were composed of 65 pupils, each. Sex education consisted of lecture and discussion and the materials were this researcher's own made, 'How do I grow? and related OHP film and video. This education was practiced 40 minutes at a time, at intervals of 2-4 days' six times during 3weeks. For sex knowledge tools, 20 item questionaries on the base of related reference books and contents of this study were used. For sex attitude tools, this researcher's own made 13 item questionaries were used which were revised and complemented and laying stress on the reference books. The data was analyzed through pc-SAS program. The homogeneity test in terms of the general characteristics of experimental and control group was analyzed through $x^2$-test and t-test. And the difference in the primary schoolers' score on knowledge and attitude about sex before and after the sex education was analyzed through t-test and ANCOVA. The results of this study are as follows : 1. The result of the homogeneity test in terms of the general characteristics of the experimental and control group showed that there were significant differences in economic standard($x^2$=2.92, P=0.052) and brotherly ties($x^2$=3.78, P=0.052). 2. Hypothesis 'After sex education, the score of primary schoolers' sex knowledge will be higher than before. 'showed statistically significant difference.(t=11.99, P=.0001) Sex education was practiced under control over subjective view of economic standard and brotherly ties which showed significant difference at the homogeneity test in terms of the general characteristics between the two groups. After this education, the results of comparing the score of primary schoolers' sex knowledge also showed significant difference between the two groups. So hypothesis I was supported since primary schoolers to have education showed noticeable results in the sex knowledge score. (F=16.52, P=.0001) 3. Hypothesis 'After sex education, primary schooler's sex attitude score will be higher than before' showed statistically significant(t=5.08, P=.0001) Sex education was practiced, too, under control over subjective view of economic standard and brotherly ties which showed significant difference at the homogeneity test in terms of the general characteristics between the two groups. Bat this time the results of comparing the primary schoolers' sex attitude showed no significant difference between the two groups. So hypothesis II was rejected since for primary schoolers to have sex education showed no noticeable results in sex attitude score. (F=3.52, P=.0628) These results of the study show that sex education gives affirmative change to the primary schooler's sex knowledge, bat short periods' sex education doesn't give any change to the sex attitude. For the establishment of the pupils' desirable sex attitude, systematic and concrete sex education fit for the pupils' developing stage should be practiced over a long period of time.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.3
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• pp.311-319
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• 2012

Purpose: One of the critical aspects on dispensing glasses is to match the center of pupils to the optical center of lenses as the mismatched glasses are able to induce uncomfortable effects called prism which has been known to induce phoria, a main cause for asthenopia in many cases. Therefore, we investigated the induced prism occurred by mismatching centers between the center of pupils and the optical center of lenses. Methods: In this study, total 103 subjects were examined whether the center of pupils and the optical center of lenses are matched in horizontal and vertical directions, and then, the data was categorized into 4 groups based on the structural components of glasses. Total amount of prism was compared to show the effect of the glasses frame on the prism induction, and the value of measured prism was compared with the German RAL-RG 915 regulations. Results: The results in respect to the horizontal component showed that the induced prism was not found in 10.7% of total subjects. 73.8% of total subjects were influenced by induced prism, the range of prism was in a tolerance level. However, the 15.5% of total subjects seemed to be influenced by prism which is out of the criterion of tolerance. In case of vertical component, 23.3% of total subjects showed no effects of prism while early adopting glasses, 54.4% of total subjects showed a little prism effect within the criterion of tolerance, and 22.3% of total subjects showed the prism effect out of the tolerance range. This data indicates that group A and B that are less likely adjustable by fitting induce more prism than group C and D in horizontal and vertical components. Conclusions: In higher refractive error condition, it was found that aligning the optical center of lenses with the center of pupils by pre-fitting of glasses frame minimized prism induction in horizontal and vertical components, which ameliorates ocular fatigue. Therefore, appropriate optometric dispensing through fitting by opticians and precise design about monocular PD and monocular Oh are necessary to improve visual perception.

• Korea Trade Review
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• v.42 no.6
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• pp.111-129
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• 2017

According to the World Bank statistics, China's contribution to global economic growth during the year of 2013-2016 was estimated at 31.6 percent. This figure is even larger than 29.0 percent, the contribution by summing each contribution of the United States, EU and Japan. The Chinese commodity trade accounts for up to 11.5 percent of world trade volume. Thus, we can consider that the Chinese economy has a strong influence on the global economy. The primary purpose of this study is to analyze the contribution level of Chinese seaborne trade volume on world economy. First, this study conducted a time-lag analysis using Moran test, so we can find that China's level of contribution to global economic growth varies from time to time. The contribution of the first phase (1999-2007) was nearly three times higher than the contributions from the second phase (2008-2016), suggesting that the overall contraction of the global trade volume starting from the subprime mortgage crisis in 2008 has continued until recently and recovery has not even occurred. Second, using the econometrics model, this study conducted an regression analysis of the impact of Chinese imports and exports in chemicals, grain, steel, crude oil, and container on global economic growth. Fixed effects model with time series data has been applied to examine the effect of Chinese seaborne trade volume on global economic growth. According to the empirical analysis of this study, China's exports of steel products, exports of container, imports of containers, imports of crude oil and imports of grain have significant contributions to global economic growth. Estimates of China's exports of steel products, exports of container, imports of containers, imports of crude oil and imports of grain are 1.023, 1.020, 1.019, 1.007 and 1.006, respectively. For example, the estimated value 1.023 of China's exports of steel products means that the growth rate can be 1.023 times higher than the current world GDP growth rate if Chinese seaborne trade volume of exports of steel products increased by one unit (one million tons). This study concludes that the expansion of China's imports and exports should be realized first to increase the global GDP growth rate. The expansion of Chinese trade can lead to a simultaneous stimulus of production and consumption in China, which can even lead to global economic growth ultimately. Thus, depending on how much China's trade will be broaden in the future, the width of global economic growth can be determined.

• Journal of the Korean earth science society
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• v.27 no.2
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• pp.159-176
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• 2006

Geographic factors and mathmatical location of the Korean Peninsula have great influences on the variation patterns and appearances over a period of ten days of summer precipitation. In order to clarify the influence of several climate factors on precise climate classification in the middle part region of the Korea, weather entropy and the information ratio were calculated on the basis of information theory and of the data of 25 site observations. The data used for this study are the daily precipitation phenomenon over a period of ten days of summer during the recent thirteen years (1991-2003) at the 25 stations in the middle part region of the Korea. It is divided into four classes of no rain, $0.1{\sim}10.0mm/day,\;10.1{\sim}30.0mm/day$, 30.1mm over/day. Their temporal and spatial change were also analyzed. The results are as follows: the maximum and minimum value of calculated weather entropy are 1.870 bits at Chuncheon in the latter ten days of July and 0.960 bits at Ganghwa during mid September, respectively. And weather entropy in each observation sites tends to be larger in the beginning of August and smaller towards the end of September. The largest and smallest values of weather representative ness based on information ratio were observed at Chungju in the beginning of June and at Deagwallyeong towards the end of July. However, the largest values of weather representativeness came out during the middle or later part of September when 15 sites were adopted as the center of weather forecasting. The representative core region of weather forecasting and climate classification in the middle part region of the Korea are inside of the triangle region of the Buyeo, Incheon, and Gangneung.

• IMMUNE NETWORK
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• v.1 no.3
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• pp.236-243
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• 2001

Background: An immunological approach for aging mechanism appears to be important. Lymphocyte subsets analysis in peripheral blood is widely performed to assess the immune status and to diagnose and monitor various diseases. Some lymphocyte subsets are known to change with age, but only few data about age-related reference ragnes for these subsets in healthy individuals have been reported. So we attempted to report reference ranges for these subsets in each age group and review changes of the results with age for the secondary studies about immune cell function as lymphocyte blast transformation and immunoglobulin gene rearrangement (VDJ) including recombination activating genes (RAG-1 and RAG-2). Methods: Lymphocyte subset analysis was performed on 302 subjects, 189 males and 113 females with age group of all decades of life. Two color direct immunofluorescene flow cytometry (FCM) was done using $Simultest^{TM}$ IMK-Lymphocyte kit (Becton Dickinson, USA), $FACScan^{TM}$ (Becton Dickinson, USA) and $FACSCalibur^{TM}$ (Becton Dickinson, USA). Lymphocyte subsets analysed were T ($CD3^+$) and B cells ($CD19^+$), helper/inducer T ($CD4^+$) and suppressor/cytotoxic T cells ($CD8^+$), helper/suppressor ($CD4^+/CD8^+$) ratio and natural killer (NK) cells ($CD3^-CD16^+/CD56^+$). The absolute numbers of each subset were calculated from total lymphocyte counts. Data collected was analysed using SAS 6.12. A P-value of < 0.05 was considered significant. Results: We reported the counts and percentages of lymphocyte and these subsets in each age group. There were no statistically significant differences between male and female subjects. The percentage of $CD4^+$ T cells, and the count of NK cells did not show the significant difference among the various age groups. The age-related changes observed in our study were as following: 1) a decrease in the percentages of T cells, B cells and $CD8^+$ T cells ; 2) a decrease in the counts of B cells and $CD8^+$ T cells ; 3) an increase in the percentage and count of NK cells ; and 4) an increase in the $CD4^+/CD8^+$ ratio. Conclusion: The characteristics of aging process appeared to be showing a marked decrease of lympocyte subsets T and B cells as well as T8 ($CD8^+$). The age-related increase of the percentage of cells bearing NK marker can be interpreted as a compensatory consequence to cope with the decrease of T cells related to the thymic involution. These changes with age appeared to be for the secondary study about immune cell function as lymphocyte blast transformation and immunoglobulin gene rearrangement.