• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.45-51
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• 1970

By means of past data, taken from the annual catches of anchovy landings in Korea, from the year 1926 to 1967, as reported in the Annual Statistical deports of Fisheries, the future annual catches from the year 1968 to 1973 were predicted by statistical extrapolation. The trend C(t) in the 42 year period above was interpreted by the least square method. Also, the ratio of the actual annual catches Ct to this trend C(t) was regarded as a stationary variate and the serial correlation coefficients $r_k$ were calculated. The type of statistical variate model was therefore determined by the correlogram. A periodical analysis, using Whittaker's method, was performed and a harmonic analysis was also performed. According to these calculations the stationary variate at was fixed and the annual catches following the year 1967 were predicted by extrapolation.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.109-113
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• 2009

Tree-ring width analysis has been used to assess the effects of air pollution on tree growth around industrial complexes. Our study was conducted to elucidate the effect of air pollutants on annual ring growth in black pines (Pinus thunbergii) of age 41$\sim$48 years around Ulsan Metropolitan City. The growth data were analyzed by multiple regression and the results are as follows: 1. The annual ring increment of black pines increased with tree age until age 40 years and then decreased gradually after age 40 years. 2. The increment of annual ring width of black pines was affected more by precipitation and evapotranspiration than air temperature. An annual ring decline appeared in the years 1968$\sim$1983, when annual ring indices below zero were observed. Decreased annual ring growth during this period may have been due to air pollution. 3. The heavy metal with the strongest effect on annual ring growth of black pines in the experimental stand was lead (Pb). The concentration of lead in the stand was estimated as over 6 ppm. 4. The technique of tree-ring width analysis may be useful for estimation of the extent of pollution in forest areas near industrial complexes.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.319-327
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• 2010

We examine the ionospheric F2-layer electron density variation by solar activity in middle latitude by using foF2 observed at the Kokubunji ionosonde station in Japan for the period from 1997 to 2008. The semi-annual variation of foF2 shows obviously in high solar activity (2000-2002) than low solar activity (2006-2008). It seems that variation of geomagnetic activity by solar activity influences on the semi-annual variation of the ionospheric F2-layer electron density. According to the Lomb-Scargle periodogram analysis of foF2 and Ap index, interplanetary magnetic field (IMF) Bs (IMF Bz <0) component, solar wind speed, solar wind number density and flow pressure which influence the geomagnetic activity, we examine how the geomagnetic activity affects the ionospheric F2-layer electron density variation. We find that the semi-annual variation of daily foF2, Ap index and IMF Bs appear clearly during the high solar activity. It suggests that the semi-annual variation of geomagnetic activity, caused by Russell-McPherron effect, contributes greatly to the ionospheric F2-layer semi-annual electron density variation, except dynamical effects in the thermosphere.

• The Journal of Asian Finance, Economics and Business
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• v.3 no.3
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• pp.67-77
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• 2016

Shareholders solely depend on annual reports to make investment, credit and other decisions. Investors expect that information should be reliable, relevant, comparable, consistent and thus easy to use for decision making. But whether the importance of annual reports to all shareholders is equally significant is a question of research. Thus, this research study tries to find out the importance of reading annual reports to the investors. A questionnaire survey is conducted on investors considering thirty one general shareholders and six brokers. This research based survey finds that most of the shareholders have no knowledge about accounting or finance and they have little knowledge about capital markets due to lack of training. This study also finds that general shareholders read an annual report at least moderately except value added statement, chairman's review, director's report and rumor. This study recommends human resource should be developed through adequate training, and annual reports should provide transparent and quality information which will ultimately increase the confidence of investors.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.4
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• pp.263-275
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• 1991

Studies on the annual performance of three different type of solar-absorption heat pump system (parallel type, series type, and generator type) are carried out by using the computer simulation. These include the calculation of solar energy from the solar collector, and the revision of computer package, developed by Oak Ridge National Laboratory, to predict the annual performance. Finally using weather data and load conditions, the annual performance are obtained. Results show that the annual operating costs of three solar-absorption heat pump systems are almost same values and 44% lower than that of the pure absorption heat pump system. The total annual input energys of solar-absorption heat pump systems are also about 44% lower than that of the pure absorption heat pump. The nominal size of the solar-absorption heat pump systems can be reduced to a value of 55% that of the pure absorption heat pump that would normally be specified under identical conditions.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.1-7
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• 2010

This study was carried out to investigate the effect of hydro power factors (e.g., irrigation area, watershed area, active storage, gross head) on annual generation capacity and operation ratio for agricultural reservoirs in Chungbuk Province with active storage of over 1 million $m^3$. The annual generation capacity and operation ratio were estimated using HOMWRS (Hydrological Operation Model for Water Resources System) from last 10-year daily hydrological data. The correlation coefficients between annual generation capacity and the hydro power factors except gross head were high (over 0.87), but the correlation coefficients between operational rate and the factors were low (below 0.28). The optimum multiple regression equations of the annual generation capacity were expressed as the functions of watershed area, active storage, and gross head. Also, the simple regression equation of annual generation capacity was expressed as a function of watershed area. The average relative root-mean-square-error (RRMSE) between observed and estimated values by the optimum multiple regression equations was smaller than that by the simple regression equation, suggesting that the former has more accuracy than the latter.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.273-281
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• 2021

The radiological safety of the spent resin treatment facility with a¹⁴C treatment capacity of 1 ton/day was evaluated in terms of the external and internal exposure of worker according to operation scenario. In terms of external dose, the annual dose for close work for 1 h/day at a distance of more than 1 m (19.8 mSv) satisfied the annual dose limit. For 8 h of close work per day, the annual dose exceeded the dose limit. For remote work of 2000 h/year, the annual dose was 14.4 mSv. Lead shielding was considered to reduce exposure dose, and the highest annual dose during close work for 1 h/day corresponded to 6.75 mSv. For close work of 2000 h/year and lead thickness exceeding 1.5 cm, the highest value of annual dose was derived as 13.2 mSv. In terms of internal exposure, the initial year dose was estimated to be 1.14E+03 mSv when conservatively 100% of the nuclides were assumed to leak. The allowable outflow rate was derived as 7.77E-02% and 2.00E-01% for the average limit of 20 mSv and the maximum limit of 50 mSv, respectively, where the annual replacement of the worker was required for 50 mSv.

• Journal of Korea Water Resources Association
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• v.45 no.5
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• pp.431-444
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• 2012

This study investigated the differences between annual maximum series and annual maximum independent rainfall event series with relatively short and long rainfall durations. Annual maximum independent rainfall events were selected by applying various IETDs and thresholds to the hourly rainfall data in Seoul for the duration from 1961 to 2010. Annual maximum independent rainfall event series decided were then compared with the conventional annual maximum series. Summarizing the results is as follows. First, the effect of IETD and threshold was not beyond the expected level. For example, as the IETD increases, the frequencies of independent rainfall events decreased similarly in their rate for both with short and long durations. However, as the threshold increases, the frequency of those with rather long durations decreased much higher. Second, The mean rainfall intensity of the independent rainfall events was found to remain constant regardless of their duration. This indicates that the annual maximum rainfall intensity could be found in a rainfall event with longer durations. Lastly, the difference between the annual maximum rainfall series and the annual maximum independent rainfall event series with rather short rainfall durations was found significantly large, which decreases with longer durations. This result indicates that the conventional data analysis method, especially for small basins with short concentration time, could lead an unrealistic design rainfall with little possibility of occurrence.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.554-563
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• 2018

In recent years, problems like the formation of the organizational culture that emphasizes the outcome, deepening of stagnation of promotion, the advent of high wages and the open era, the shortage of talented human resources has occurred. Thus, public agencies have an effort to improve the traditional seniority supply wage system and have carried out introducing the performance annual salary system. This study analyzed performance annual salary system problems and the improvement plan in addition to the investigation of the recognition of employees related to the outcome annual salary system of recent public agencies. Performance annual salary system of public agencies was introduced in conjunction with the evaluation of the public agencies. Performance annual salary system of this way were studied something that it have been properly secured, what is problems generated by the annual salary system fusing process and improvement about them. According to the study, It found that there are various problems like strong negative perceptions of overall performance annual salary system, the sense of discomfort occurrence associated with the implementation of the outcome annual salary system, salary piling of objectivity for the performance evaluation, etc. In order to improve these problems, It is necessary to converse of negative recognization, eliminate discomfort of performance annual salary system, provide fair evaluation criteria of the outcome, and due to the implementation annual salary system, and clarification of sectoral performance concepts and criteria.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.397-404
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• 2000

A total of 65 rain gauges with Automatic Weather Station(AWS) were used to regional analysis of precipitation. Nine cluster regions were identified using geographical locations, maximum, mean, standard deviation of 1 day maximum rainfalls, mean annual precipitation and rainfall of rainy season in Korea. The mean annual precipitation, geographical locations, and the synoptic generating mechanisms were used to identify th five climatological homogeneous regions in Korea. Number of final regions by mean annual precipitation and cluster methods divided into five regions in Korea.