• Analytical Science and Technology
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• 제24권3호
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• pp.193-199
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• 2011

The purpose of this experiment is to evaluate the stability of products according to the storage methods, the period of use, and the diurnal variations through the short term stability experiment of recombinunt protein A (rProtein A) produced in AP Tech Co. That is, we investigated how long the stability of the products would last, when we used the samples frozen at $-20^{\circ}C$, which is one of the storage conditions of the produced rProtein A and then kept them refrigerated at $4^{\circ}C$. The experiment was conducted for 8 weeks and 6 experiment points were established. The experiment was done by thawing the samples frozen at $-20^{\circ}C$ at room temperature, and then refrigerating them at $4^{\circ}C$. In addition, experiments for endotoxin, bioburden, HPLC purity, and concentration were conducted. As a result of the experiment, 0.5 EU/mg endotoxin was detected both at the beginning and at the 8th week and bioburden was not analyzed. In the case of purity, it showed 99.23~99.90% at 210 nm (RSD% 0.23%) and 100% at 280 nm, which meant the change into other materials didn't happen and there was no material degradation characteristics. Finally, we also found the fact that the concentration stayed stable at 55.15 mg/mL (RSD% 0.55%) both at the beginning and at the end. From the experiment results, we were able to conclude that the stability at the condition to store rProtein A at 4 oC for 8 weeks was procured without producing microorganisms or having material degradation characteristics.

• Asia pacific journal of information systems
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• 제17권2호
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• pp.97-122
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• 2007

Conventional networking and telecommunications infrastructure characterized by wires, fixed location, and inflexibility is giving way to mobile technologies. Numerous research reports point to the ultimate domination of wireless communication. With the increasing prevalence of advanced cell-phones, various mobile data services (hereafter MDS) are gaining popularity. Although cellular networks were originally introduced for voice communications, statistics indicate that data services are replacing the matured voice service as the growth engine for telecom service providers. For example, SK Telecom, the Korea's largest mobile service provider, reported that 25.6% of revenue and 28.5% of profit came from MDS in 2006 and the share is growing. Statistics also indicate that, in 2006, the average revenue per user (ARPU) for voice didn't change but MDS grew seven percents from the previous year, further highlighting its growth potential. MDS is defined "as an assortment of digital data services that can be accessed using a mobile device over a wide geographic area." A variety of MDS have been deployed, with a few reaching the status of killer applications. Many of them need to access the Internet through the cellular-phone infrastructure. In the past, when the cellular network didn't have acceptable bandwidth for data services, SMS (short messaging service) dominated MDS. Now, Internet-ready, next-generation cell-phones are driving rich digital data services into the fabric of everyday life, These include news on various topics, Internet search, mapping and location-based information, mobile banking and gaming, downloading (i.e., screen savers), multimedia streaming, and various communication services (i.e., email, short messaging, messenger, and chaffing). The huge economic stake MDS has on its stakeholders warrants focused research to understand associated dynamics behind its adoption. Lyytinen and Yoo(2002) pointed out the limitation of traditional adoption models in explaining the rapid diffusion of innovations such as P2P or mobile services. Also, despite the increasing popularity of MDS, unexpected drop in its usage is observed among some people. Intrigued by these observations, an exploratory study was conducted to examine decision factors of MDS usage. Data analysis revealed that the increase and decrease of MDS use was influenced by different forces. The findings of the exploratory study triggered our confirmatory research effort to validate the uni-directionality of studied factors in affecting MDS usage. This differs from extant studies of IS/IT adoption that are largely grounded on the assumption of bi-directionality of explanatory variables in determining the level of dependent variables (i.e., user satisfaction, service usage). The research goal is, therefore, to examine if increase and decrease in the usage of MDS are explained by two separate groups of variables pertaining to information quality and system quality. For this, we investigate following research questions: (1) Does the information quality of MDS increase service usage?; (2) Does the system quality of MDS decrease service usage?; and (3) Does user motivation for subscribing MDS moderate the effect information and system quality have on service usage? The research questions and subsequent analysis are grounded on the two factor theory pioneered by Hertzberg et al(1959). To answer the research questions, in the first, an exploratory study based on 378 survey responses was conducted to learn about important decision factors of MDS usage. It revealed discrepancy between the influencing forces of usage increase and those of usage decrease. Based on the findings from the exploratory study and the two-factor theory, we postulated information quality as the motivator and system quality as the de-motivator (or hygiene) of MDS. Then, a confirmative study was undertaken on their respective role in encouraging and discouraging the usage of mobile data service.

• Korean Journal of Soil Science and Fertilizer
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• 제34권5호
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• pp.350-357
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• 2001

This study was performed to evaluate an effect of soil water retention and chinese cabbage growth on application of super water absorbent(CPAM-AS-hyd). In seedling experiments, the CPAM-AS-hyd application rates were 0, 5 and 10kg/10a in bed soil of experimental field. The emergence percentage of chinese cabbage was increased by 9% with application of CPAM-AS-hyd otherwise emergence rates was delayed by 1 day. Water content in soil with CPAM-AS-hyd(10kg/10a) was 27.6%(v/v) at 10days after irrigation and that of control was 20.7%. The CPAM-AS-hyd application caused to alleviate wilting point by 5 days. The content of NO3-N in bed soil was increased with CPAM-AS-hyd application. In the field experiments, as the CPAM-AS-hyd application rates were 5kg/10a and 10kg $10a^{-1}$, the irrigation amounts applied during the growth periods were 1.87 ton, 1.65 ton and 1.53 ton at-0.2bar irrigation frequence and 1.38 ton, 1.25 ton and 1.15 ton at -0.5bar for growth period control, in the CPAM-AS-hyd of 5kg $10a^{-1}$ and CPAM-AS-hyd of 10kg $10a^{-1}$ plot, respectively. The CPAM-AS-hyd application caused to increase yield of chinese cabbage by 9~34% as compared to the control. The contents of $NH_4-N$ and $NO_3-N$ in soil were decreased with the CPAM-AS-hyd application in 10 days after transplanting of chinese cabbage, but the contents of those in soil were increased with the CPAM-AS-hyd application as compared to the control in 20 days after transplanting. The T-N, CaO, MgO and $K_2O$ contents in chinese cabbage increased due to the CPAM-AS-hyd application however $P_2O_5$ content was similar to the control.

• Korean Journal of Agricultural and Forest Meteorology
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• 제3권3호
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• pp.135-142
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• 2001

This study attempts to categorizes the factors of forest fire occurrences based on regional meteorologic data and general forest no characteristics of 18 cities and guns in Kangwon province. lo accomplish this goal, some statistical analyses such as analysis of variance, correspondence analysis and multidimensional scaling were adopted. To reveal the forest fires pattern of study region, a categorization process was conducted by employing the quantification approach which modified and quantified the metric-data of fire occurrence dates. Also, The fire occurrence similarity was compared by using multidimensional scaling for each study region. The major results are summarized as follows: It was found that the meteorological factors emerged as different to each region are average and maximum temperature, minimum dew point temperature and average and maximum wind speed. In the result of correspondence analysis representing relationships between fire causes and study regions, Kangrung is caused by arsonist, Chulwon, Hwachen and Yanggu caused by military factor, Sokcho and Chunchen caused by the debris burning, and Samchuk caused by general man-caused fires, respectively. Finally, the forest fire occurrence pattern of this study regions were divided into five areas such as, group I including Samchuk, Kangryung, Chunchen, Wonju, Hongchen and Hhoingsung, group II including Donghae, Taebaek, Yangyang and Pyongchang, group III including Jungsun, Chulwon and Whachen, group Ⅵ including Gosung, Injae and Yanggu, and group V including Shokcho and Youngwol.

• Journal of the Korean association of regional geographers
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• 제3권2호
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• pp.209-225
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• 1997

Today, rapid progress of urbanization is discovered commonly in many countries, especially in developing countries, which has led to spatial order and development process of city. Historically, Taegu was a walled city and formed mono-nucleus which was restricted by the castle. As the city grew gradually, the castle was removed as a result of diversification in traffic network, change of socio-economic environment, formation of industrial base and functional distribution. According to reconstruction maps of residential patterns, there was distinctive residential segregation among ethnic groups. Koreans in Taegu in 1939, aggregated densely in the southern and western parts of the city. The Japanese were concentrated densely in the northern and eastern parts of Taegu. And the street pattern within residential areas of the Korean people was shaped like a maze type in contrast with Japanese residential areas, which showed grid pattern of streets. This is another general pattern of almost all colonial cities, especially in Asia. Through this process, today it appears that, out of overall residential areas which occupy the highest ratio in urban land use, those for eminent people influence the functional development of urban spatial structure very heavily as a key point in urban residetial structure. Truly, residential segregation can be seen as the spatial manifestation of uneven distribution of such important scarce resources as housing and residential environment. In this study, the characteristics of locational distribution of the eminent people show their socially and economically stabilized standing in Taegu, taking the aforesaid situation as a background of the study. And the process of this study is as follows ; to examine the forming process of residential areas in the city as a theoretical supporting, to put in order on classical interpretation to formation of residential areas, and general type modern residential areas formation, and economic decision factor of land use. Therefore, this study aims to examine growth and development of eminent persons' residential areas and, at the same time, extract locational characteristics through the pattern of eminent persons' location and predict changes in the future.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• 제18권1호
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• pp.51-62
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• 2020

This study was conducted to develop a method for depth assessment of embedded sources using gamma-spectrum ratio and for the evaluation of field applicability. To this end, Peak to Compton and Peak to valley ratio changes were evaluated according to ¹³⁷Cs, ⁶⁰Co, ¹⁵²Eu point source depth using HPGe detector and MCNP simulation. The effects of measurement distance of PTV and PTC methods were evaluated. Using the results, the source depth assessment equation using the PTC and PTV methods was derived based on the detection distance of 50 cm. In addition, the sensitivity of detection distance changes was assessed when using PTV and PTC methods, and error increased by 3 to 4 cm when detection distance decreased by 20 cm based on 50 cm. However, it was confirmed that if the detection distance was increased to 100 cm, the effects of detection distance were small. And PTV and PTC methods were compared with the two distance measurement method which evaluates the depth of source by the change of net peak counting rate according to the detection distance. As a result of source depth assessment, the PTV and PTC showed a maximum error of 1.87 cm and the two distance measurement method showed maximum error of 2.69 cm. The results of the experiment confirmed that the accuracy of the PTV and PTC methods was higher than two distance measurement. In addition, Sensitivity evaluation by horizontal position error of source has maximum error of less than 25.59 cm for the two distance measurement method. On the other hand, PTV and PTC method showed high accuracy with maximum error of less than 8.04 cm. In addition, the PTC method has lowest standard deviation for the same time measurement, which is expected to enable rapid measurement.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제9권3호
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• pp.155-164
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• 1997

A comprehensive and systematic field monitoring program was initiated since October 1989, in order to investigate the temporal and spatial variation of shoreline position at northern part of Pea Island, North Carolina. Aerial photographs were taken every two months on the shoreline extending from the US Coast Guard Station at the northern end of Pea Island to a point 6 miles to the south. Aerial photographs taken were digitized initially to obtain the shoreline position data. in which a wet-dry line visible on the beach was used to identify the position of shoreline. Since the wet-dry line does not represent the “true" shoreline .position but includes the errors due to the variations of wave run-up heights and tidal elevations at the time the photos taken, it is required to eliminate the tide and wave runup effects from the initially digitized shoreline .position data. Runup heights on the beach and tidal elevations at the time the aerial photographs taken were estimated using tide data collected at the end of the FRF pier and wave data measured from wave-rider gage installed at 4 km offshore, respectively A runup formula by Hunt (1957) was used to compute the run-up heights on the beach from the given deepwater wave conditions. With shoreline position data corrected for .wave runup and tide, both spatial and temporal variations of the shoreline positions for the monitoring shoreline were analyzed by examining local differences in shoreline movement and their time dependent variability. Six years data of one-mile-average shoreline indicated that there was an apparent seasonal variation of shoreline, that is, progradation of shoreline at summer (August) and recession at winter (February) at Pea Island. which was unclear with the uncorrected shoreline position data. Determination of shoreline position from aerial photograph, without regard to the effects of wave runup and tide, can lead to mis-interpretation for the temporal and spatial variation of shoreline changes.nges.

• Korean Journal of Environmental Agriculture
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• 제28권2호
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• pp.194-201
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• 2009

To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008${\sim}$7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001${\sim}$0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01${\sim}$7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07${\sim}$3.06 % from Kongju agricultural land to watershed after applied pesticides.

• Journal of Home Health Care Nursing
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• 제5권
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• pp.84-99
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• 1998

The objectives of this study are to identify the actual educational contents of management for head nurse and to propose the educational subjects according to identity the needs of head, charge, and staff nurses. The subjects were investigated the actual Management Development Programs and educational needs of head nurses and prospective nurse manager(charge nurse, staff nurse with a lot of clinical experiences) in general hospitals. The tools were composed of two questionnaires: One was developed from the literature review for making items to measure actual situation. The other was revised Katz's model for measurement of educational needs. The first respondents of actual situation were 27 general hospitals with over 400 beds in Seoul and the second respondents were 89 head nurses, 67 charge nurses and 136 nurses at 3 hospitals by convenient sampling out of 27 general hospitals. Data were collected by telephone interview, mail questionnaire and visiting from 7th of October through 30th of November in 1997. In data analysis, general characteristics of the respondents and actual status of Management Development Programs were analyzed by frequency and percentage. Educational needs according to general characteristics were analyzed by ANOVA The results were as follows: 1. Actual situation of Management Development Program 1) Seven hospitals(26%) had Management Development Program for prospective managers and 14 hospitals (52%) for head nurses. 2) Education Department existed in 14 hospitals (52%). 3) One hospital(4%) had top level managers took part in the Management Development. 4) Two hospitals selected head nurse, who had finished courses of Management Development. Eight hospitals(30%) assessed educational needs. The assessment tools consisted of making a question via questionnaire(75%), determining at department meeting(12%) and interview(13%). 5) Educational programs had 3 types: 10 lecture type, 7 discussion type and 4 role play type programs. 6) One hospital evaluated the change of learner's attitude. 7) Four hospitals scored educational point, but that was measured only by attending. 8) Actual Management Development Programs were as follows. parenthesis indicates the number of hospitals. (1) Management Development Programs for Prospective manager. Role perception of Middle level Manager (1) . Role reconstruction of Nurse Manager (1). Workshop for Charge Nurse (1). Nursing Delivery System and Nursing Process (1). Communication (1). Motivation (1) (2) Management Development Programs for Head nurse.. Head nurse's Role (5). Administrative Work (7). Service Education (4). Prevention and Countermeasure of Nursing Incidence (3). Appraisal (3) 2. The results of needs on Management Development subject 1) The educational needs of all respondents on 3 skill domains showed positive agreement to strongly positive agreement. 2) High priority(more than 4.5) items were 12 of 24 Human skill items(50%), 1 of 6 Technical skill items(16%), and 2 of 13 Conceptual skill items (15%). 3) Out of high priority items, 8 items were instituted. 4) All respondents showed high needs on 3 skill domains regardless of 3 positions (head nurse, charge nurse, and nurse). Educational needs of Human skill domain, according to position were 108. S, 108.7, 106.8 (mean score = 72) , needs of Technical skill domain were 26.5, 26.6, 26.I(mean score=18), and needs of Conceptual skill domains were 56.9,56.7, 55.1(mean score=39). 5) Needs of 3 skill domains according to clinical career showed significant difference. Out of respondents, nurses with career of over 16years showed lowest degree of needs in Human skill domains(F=4.47, P=.004) and Conceptual skill domain(F=2.93, P=.034). 6) Educational needs according to educational background were not significant difference. But out of respondents, nurses educated at 3-year junior college relatively showed lowest needs in all of the 3 skill domains. With the above-mentioned findings, further study is necessary for generalization of this study at hospitals with different bed size and location. Also it is needed to study about management skill of nurse and charge nurse, and effective educational method.

• The Journal of Korean Academy of Prosthodontics
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• 제47권3호
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• pp.335-341
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• 2009

Statements of problem: Adequate bone quality and quantity were important to achieve initial stability and to prevent early failures. However there were few published data available regarding the actual effect of dimensional change in implant geometry on initial stability. Purpose: The purpose of the current study was to investigate the influence of diameter and length changes on initial stability of implants. Material and methods: Four types of dummy bone (D1, D2, D3 and D4) consisted of cortical and cancellous layers with different thickness were simulated. Implants which had similar surface area to each other ($3.5{\times}13.0-mm$, $4.0{\times}11.5-mm$, $4.5{\times}10.0-mm$, $5.0{\times}8.5-mm$) were inserted in dummy bones. Implant stability as a function of peak insertion torque and resonance frequency values were recorded for each implant. Results: 1. Bone quality was a major influential factor to achieve initial stability (P <.05). 2. In D1, D2 and D3 dummy bones, implant stability quotient values were not significantly different to each other (P >.05), however insertion torques were increased with wider and shorter implants (P <.05). 3. In D4 dummy bone, implant stability quotient values and insertion torques were decreased with wider and shorter implants (P <.05). Conclusion: From a point of view of initial stability, it is suggested that use of wide and short implant may be helpful in avoiding bone augmentation procedures in area of adequate bone quality.