• 한국환경과학회지
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• 제24권6호
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• pp.785-792
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• 2015

This study investigates weekday/weekend characteristics of $PM_{10}$ concentration and chemical composition of water-soluble ions in Busan in the spring of 2013. Contribution rate of water-soluble ions to PM10 concentration in weekday/weekend were 41.5% and 38.5%, respectively. Contribution rate of SO_4{^{2-}}$ to total ion mass in weekday/weekend were 30.4% and 33.8%, respectively. Contribution rate of total inorganic water-soluble ions in PM10 in weekday/weekend were 42.2% and 39.1% (mean 41.4%), respectively. $[NO_3{^-}/SO_4{^{2-}}]$ ratio in weekday/weekend were 1.01 and 0.97(mean 0.99), respectively, which indicated that weekday ratio was higher. Contribution rate of sea salts and $Cl^-/Na^+$ ratio in PM10 in weekday/weekend were 8.1% and 7.6%, 0.37% and 0.41%, respectively. This research will help understand chemical composition of water-soluble ions during the weekday/weekend and will be able to measure the contribution level of artificial anthropogenic source on urban air.

• 대한인간공학회지
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• 제35권5호
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• pp.361-370
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• 2016

Objective:The aim of this study is to evaluate contributions of individual finger forces associated with various levels of submaximal voluntary contraction tasks. Background: Although many researches for individual finger force have been conducted, most of the studies mainly focus on the maximal voluntary contraction. However, Information concerning individual finger forces during submaximal voluntary contraction is also very important for developing biomechanical models and for designing hand tools, work equipment, hand prostheses and robotic hands. Due to these reasons, studies on the contribution of individual finger force in submaximal grip force exertions should be fully considered. Method: A total of 60 healthy adults without any musculoskeletal disorders in the upper arms participated in this study. The young group (mean: 23.7 yrs) consisted of 30 healthy adults (15 males and 15 females), and the elderly group (mean: 75.2 yrs) was also composed of 30 participants (15 males and 15 females). A multi-Finger Force Measurement (MFFM) System developed by Kim and Kong (2008) was applied in order to measure total grip strength and individual finger forces. The participants were asked to exert a grip force attempting to minimize the difference between the target force and their exerted force for eight different target forces (5, 15, 25, 35, 45, 55, 65, and 75% MVCs). These target forces based on the maximum voluntary contraction, which were obtained from each participant, were randomly assigned in this study. Results: The contributions of middle and ring fingers to the total grip force represented an increasing trend as the target force level increased. On the other hand, the contributions of index and little fingers showed a decreasing trend as the target force level increased. In particular, Index finger exerted the largest contribution to the total grip force, followed by middle, ring and little fingers in the case of the smallest target force level (5% MVC), whereas middle finger showed the largest contribution, followed by ring, index and little fingers at the largest target force levels (65 and 75% MVCs). Conclusion: Each individual finger showed a different contribution pattern to the grip force exertion. As the target force level increase from 5 to 75% MVC, the contributions of middle and ring fingers showed an increasing trend, whereas the contributions of index and little fingers represented a decreasing trend in this study. Application: The results of this study can be useful information when designing robotic hands, hand tools and work equipment. Such information would be also useful when abnormal hand functions are evaluated.

• 한국초지조사료학회지
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• 제20권2호
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• pp.77-84
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• 2000

Eight-week old perennial ryegrass (Lolium perenne L. cv. Reveille) plants were exposed to different NO3-concentrations or osmotic stress with NaCI. Previously labeled "N was chased during 14 days of non-labeled'NO3 feeding in order to investigate NO3 metabolism in relation to osmoregulation. The short termmeasurement of osmotic potential showed that the extemal concentration of Nos- had not great effect on theosmotic potential, but that osmotic adjustment was observed in NaCl-treated plants. Total uptake of NO 3 - waslargely increased by increasing supply level of NO3 while it was depressed by exposing to osmotic stress.Nitrate reduction increased to more than 29% by increasing extemal NO,- concentration from 1 mM to 10mM. When osmotically stressed with NaCI, nitrate reduction was depressed to about 37% as compared to thecontrol. The decrease in translocation of reduced N into leaves was also observed in NaCl exposed plants. Inthe medium exposed to 10 mM NO,., osmotic contribution of nitrate to cumulative osmotic potential wasdecreased, and it was osmotically compensated with soluble carbohydrate. When osmotically stressed withNaC1, the contribution of chloride was much higher than that of nitrate. The present data indicate that N03-in plant tissues, factually affected by the assimilation of this ion, plays an active role in osmotic regulation incorrelation with other osmotica such carbohydrate and chloride.(Key words : Nitrate metabolism, Osmotic stress, Nitrate supply level, Osmoregulation)ate supply level, Osmoregulation)

• 한국도로학회논문집
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• 제15권2호
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• pp.169-181
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• 2013

PURPOSES : This study is to suggest the Influence of road capital to industry and productivity growth in South Korea. METHODS : Based on the literature review, The relevant policy questions addressed in this report are : cost reduction and Scale elasticities of road, effect of road capital stock on demand for labor, capital and materials, marginal effect of road, industry TFP growth decomposition. RESULTS : The marginal benefits of the road capital at the industry level were calculated using the estimated cost elasticities. Demand for the road capital services varies across industries as do the marginal effects. The marginal benefits are positive for the principal industries. This suggests that for these industries the existing stock of road capital may be under supplied. The contribution of road capital to TFP growth is positive in principal industries. The main contribution of road capital is in the manufacturing industries ; the magnitudes of contribution varies among industries. These results indicate that growth in exogenous demand is most important contributor to TFP growth. CONCLUSIONS : The road capital have a significant effect on employment, private capital and demand for materials inputs in all industries. At a given level of output, an increase in road capital lead to variety to demand for all inputs in all industries.

• 품질경영학회지
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• 제46권2호
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• pp.283-300
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• 2018

Purpose: Since the servant leadership of project managers is seemingly related to the project performance by influencing project team members' positive attitude and behavior, this study attempts to provide empirical evidence for a link between servant leadership and project performance. In addition, the present study investigates the mediating effects of customer satisfaction on the servant leadership-project performance relations. Methods: The data of servant leadership and project performance were collected from 185 project team members of a company providing IT service, and customer satisfaction data were collected from 100 project clients served by the company. Before testing the hypotheses, we calculated aggregation statistics(e.g., $r_{wg}$, ICC(1), and ICC(2)) to ensure appropriate aggregation of servant leadership scores. The statistics confirmed the use of 67 team level servant leadership scores with project performance and customer satisfaction. Results: The results show that servant leadership is significantly related to three project performance measures(perceptions of performance contribution and sales contribution, and actual project profits) in the current team-level sample. Results also indicate that the clients' perception of customer satisfaction shows a mediating effect in the process of servant leadership affecting sales contribution of project performance. Conclusion: The present study empirically confirms that servant leadership plays a major role in enhancing project performance on team level analysis. The results suggest that servant leadership increases customer satisfaction since the project managers serve and care for their team members which translate into effective customer service. Theoretical and practical implications are reviewed, and limitations of the study and suggestions for future research are addressed.

• 간호행정학회지
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• 제17권2호
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• pp.168-179
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• 2011

Purpose: The purpose of this study was to identify level of recognition of the importance, satisfaction and contribution of APNs' role by physicians, nurses, and advanced practice nurses. Method: Perceived importance and satisfaction were measured with a 23-item questionnaire on APN role with 5 subcategories. APNs' contribution was investigated using a 13-item outcome questionnaire developed by the researchers. Between August 15 and October 31, 2009, the researchers collected data from 68 physicians, 265 nurses, and 23 APNs all working in a single tertiary hospital. Data were analyzed using descriptive statistics, Kruskal-Wallis Test with Bonferroni's Correction and scatter plot. Result: The importance (3.24~3.39, 4 point scale), satisfaction (3.02~3.13, 4 point scale), and contribution of APNs' role (3.39~4.12, 5 point scale) were well recognized by the health care professionals. All the three health care professional groups rated APNs' contribution high in medical service management, continuity of care, patient accessibility, improvement in patient satisfaction, and patient and family education. 'Importance-Satisfaction Analysis' showed that patient data management by APNs needed greater effort. Conclusions: The findings show that the importance, satisfaction, contribution of APNs' role are recognized, and indicate a need for further development of APNs' role through efforts to overcome the gaps identified through this research.

• 보건행정학회지
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• 제17권1호
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• pp.50-74
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• 2007

The purpose of this study was to identify a determent of mastery approach goal and performance approach goal using a basic concept of goal orientations and goal setting theory, and to evaluate a preference of goal achievement index as a balance score card (BSC). The study model proposed had a adoptable level of goodness of fit index(.94) and root mean square residual(.08). The meditating variable, goal contribution, totally mediated the impact of goal commitment, Y-theory human behavior, and self-efficacy but organizational resource contribution for pursuing goal orientation. Moreover, goal contribution significantly determined mastery approach goal(p<.01) and performance approach goal(.05). In standardized effects, the most powerful antecedent of mastery approach goal and performance approach goal were in order of organizational resource contribution(.27/.28), goal contribution(.21/.17), self-efficacy(.07/.06), and Y -theory human behavior and goal commitment(.05/.05), respectively. Moreover, goal contribution had a more powerful impact on mastery approach goal(.21) rather than performance approach goal(.17). In the preference of BSC, all job types preferred learning and growth index in first. In the second preference, medical doctors and pharmacists chose financial results, nurses customer service, and office managers internal processes. Each job type reflected its' own preferred BSC index to that of the other job types. In comparing a preference of four BSC index of each own job type, it was statistically different at p<.001. In conclusion, one who emphasize organizational goal contribution in pursuing goal orientation has a more strong orientation toward mastery approach goal rather than performance approach goal. A hospital should overcome and harmonize the different preferences of four BSC index since the differences might cause organizational conflicts among job types with having each unique professional norm.

• 한국물환경학회지
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• 제35권6호
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• pp.497-509
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• 2019

After the Total Maximum Daily Loads(TMDLs) was applied, it became beyond the limit of concentration management. However, it does not adequately reflect the characteristics of various watersheds, and causes problems with local governments because of the standard flow set. Thus, in this study, the Han River system is organized into four groups in estimating the Pollution Contribution by applying the Flow Duration Curve(FDC) created by the daily flow of data from the HSPF. And the method of this study is expected to be valuable as basic data for the TMDLs. As a result, Group I contains the main watersheds with no large hydraulic structures and tributary watersheds. There is no specificity in the FDC and the Pollution Contribution is estimated as rainfall runoff. Group II contains watersheds near the city where the FDC is maintained above a certain level during the Low Flow Conditions and the Pollution Contribution is estimated as the discharge flow of large scale point pollution facilities. Group III contains the main watersheds in which the large hydraulic structures are installed and FDC is curved in the Low Flow Conditions. So the Pollution Contribution is estimated as the water quality of the large hydraulic structures. Group IV contains the upstream in mainstream watersheds in which the large hydraulic structures are installed and the FDC is disabled before the Low Flow Conditions. As the flow is concentrated in the High Flow Conditions, the non-point pollution sources are estimated as the Pollution Contribution.

• 한국소음진동공학회논문집
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• 제18권8호
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• pp.805-815
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• 2008

Transfer path analysis(TPA) and panel contribution analysis(PCA) have been used widely to reduce interior noise of mechanical systems. TPA enables us to decompose interior noise into air-borne and structure-borne noises and estimate the path contribution of noise sources. PCA is also used to identify the noise contribution of each sub-panel in vibro-acoustic systems. In this paper, TPA and PCA are applied to wheel loader, one of the heavy construction equipments. Firstly, TPA for air-borne noise is conducted to estimate the contribution of air-borne sources using pressure transfer function. Thereafter, TPA for structure -borne noise is employed to verify the results of air-borne source quantification through the synthesis of two results. Secondly, PCA is performed by both TPA using pressure transfer function between panels inside the cabin and boundry element method(BEM) for the cabin of wheel loader with various boundary conditions. As a results, it was found that TPA conducted by experiments and PCA accomplished by both experiments and BEM are very effective methods in analyzing the path and contribution of the noises for reducing an interior noise level in the wheel loader system.

• 한국수소및신에너지학회논문집
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• 제34권2호
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• pp.100-112
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• 2023

This study evaluated the contribution of carbon neutrality by calculating the carbon reduction amount and reduction intensity targeting the hydrogen pilot city and applying it to the carbon neutral reduction target. In the building sector, the reduction amount for 2030 was 10.8% on average. In addition, by 2050, the contribution to carbon neutrality of plan A was 14.1% on average, and the contribution to carbon neutrality of plan B was 15.1% on average. In the 2030 reduction amount of the transportation sector, the contribution to carbon neutrality was 138.4% on average. In addition, by 2050, the contribution to carbon neutrality in plan A was 82.5% on average, and the contribution to carbon neutrality in plan B was 74.9%. From the above research results, additional carbon reduction is possible when creating a hydrogen city, so it will be used as a basis of city-level carbon neutral model. It will also be used as a basis for technology development and investment promotion for various hydrogen supply methods in the future.