Cosmic rays are ions that move at relativistic speeds. They generate secondary cosmic rays by successive collisions with atmospheric particles, and then, the secondary particles reach the ground. The secondary particles are mainly neutrons and muons, and the neutrons are observed by the ground neutron monitor. This study compared the diurnal variation in cosmic ray intensity obtained via harmonic analysis and that obtained through the pile-up method, which was examined in a previous study. In addition, we analyzed the maximum phase of the diurnal variation using four neutron monitors with a cutoff rigidity below approximately 6 GV, located at similar longitudes to the Oulu and Rome neutron monitors. Expanding the data of solar cycles 20–24, we examined the time of the maximum cosmic ray intensity, that is, the maximum phase regarding the solar cyclic modulation. During solar cycles 20–24, the maximum phase derived by harmonic analysis showed no significant difference with that derived by the pile-up method. Thus, the pile-up method, a relatively straightforward process to analyze diurnal variation, could replace the complex harmonic analysis. In addition, the maximum phase at six neutron monitors shows the 22-year cyclic variation very clearly. The maximum phase tends to appear earlier and increase the width of the variation in solar cycles as the cutoff rigidity increases.
Purpose - In this study, it is classified the service quality dimension of mobile shopping app using Kano model. In addition, it is evaluated quality factors suitable for strategic management from the viewpoint of service provider through mobile application through binary dimension analysis.
Research design, data, and methodology - In this study, seven quality dimensions such as information quality, reliability, immediacy, convenience, design, security and customer service were derived through related studies to make binary shopping quality app quality measurement. 37 sub-variables were set by each quality dimensions. Each questionnaire was composed of positive and negative items like Kano's proposed method, and the satisfaction coefficient suggested by Timko(1993) was examined to understand the influence of each factors on customer satisfaction.
Results - As a result of research, shopping app users perceived unity quality factor in most items of service quality dimension such as information quality, reliability, immediacy, convenience and customer service. In addition, the satisfaction coefficient showed a good impression, quick response of the result, fast delivery, and the unsatisfactory coefficient showed more interest in personal information such as payment method safety, and transaction security. As a result of research, shopping app users perceived unity quality factor in most items of service quality dimension such as information quality, reliability, immediacy, convenience and customer service. And, in information quality, the information overload was classified as an apathetic quality component, while the related information provision belonged to an attractive quality component. In reliability quality, customized service provision was classified as an attractive quality component. In instant connectivity, the quality of the connection during transport was classified as an attractive quality component. In convenience quality, access to product information was classified as a one-way quality component. All components of designs quality were classified as attractive quality components, and in security quality, all of their components were all classified as one quality component. Lastly, in customer service, they components were all classified as a single quality component. In addition, the satisfaction coefficient showed a good impression, quick response of the result, fast delivery, and the unsatisfactory coefficient showed more interest in personal information such as payment method safety, and transaction security.
Conclusion - In the online service environment, which is difficult to differentiate in terms of upward upgrading only by technological implementation and function, the results of this study can be suggested as a differentiating factor for major channels with customers rather than improve the brand image.
기존의 저수지 운영 연구들은 미래의 기후가 과거와 유사하다는 정상성의 가정을 전제로 하였다. 하지만 기후의 비정상성으로 인해 불확실성이 더욱 커질 경우에는 큰 불확실성에서도 안정된 최적해를 찾을 수 있는 로버스트 최적화 과정(Robust Optimization, 이하 RO)이 필요하다고 알려져 있다. RO는 입력자료의 비정상성으로 인해 야기되는 불확실성을 제어하는 로버스트 항을 목적함수에 추가하여 기존의 최적화 방법을 개선한다. 본 연구는 기후변화의 비정상성을 대비하는 저수지 운영규칙 산정을 위해 추계학적동적계획법(Stochastic Dynamic Programing, 이하 SDP)과 RO를 결합하는 Robust-SDP를 제안하였고, 이를 최근 4년간 가뭄을 겪었던 보령댐에 적용하였다. 즉, 비정상성이 반영된 미래 유입량 자료를 생성하고 이를 6가지의 평가지표와 2가지의 의사결정 지원그림을 사용하여 과거 유입량 자료로부터 산출된 저수지 운영규칙의 수행능력을 평가하 였다. 그 결과, Robust-SDP가 기후의 비정상성 하에서 극단적인 물 부족 사건의 발생률과 물 부족 사건의 실패의 크기를 감소시켰지만, 작은 크기의 물 부족 발생률은 증가하는 상충관계(trade-off)를 가져옴을 확인할 수 있었다. 이를 바탕으로 의사결정자가 우선시하는 평가지표의 결과에 따라 최적화 모형을 선택할 수 있음을 제안하였다.
This study was carried out to gather basic data for the purpose of proposing a plan to improve the water quality and conserve the aquatic ecosystem of the Singu Agricultural Reservoir in Korea. The water quality, sediment composition, benthic macroinvertebrate distribution, and fish distribution in the Singu Reservoir were analyzed; the reservoir is located close to farmlands, forests, villages, and livestock breeding areas. The results of the water quality analysis are as follows: 5.8~7.8 mg/L for dissolved oxygen, 13.1~20.7 mg/L for chemical oxygen demand, 14.4~18.8 mg/L for suspended solid, 0.96~1.70 mg/L for total nitrogen, 0.07~0.11 mg/L for total phosphorous, and 41.9~49.8 μg/L for chlorophyll-a. In total, 75 benthic macroinvertebrate specimens belonging to 4 classes, 7 orders, 14 families, and 17 species were recorded. The ecological scores of the benthic macroinvertebrate communities ranged from 11 to 23. Fish specimens recorded belonged to two families and four species. The dominant fish species were Carassius auratus and Pseudorasbora parva, both of which are water-pollutant tolerant species.
The aim of this study was to collect crucial data for the improvement of water quality and ecosystem conservation by analyzing water samples, sediments, benthic macroinvertebrates, and fish in the Seosan reservoir. The average values of water quality parameters from 2001 to 2016 were a chemical oxygen demand of 10 mg/L, total nitrogen of 1.22 mg/L, and total phosphorus of 0.074 mg/L. Cadmium was detected in the range of 0.531–0.748 mg/kg in the reservoir sediment. Fish belonging to 6 families and 9 species were identified in the reservoir. The dominant species were Carassius auratus and Micropterus salmoides. Benthic macroinvertebrates belonging to 22 families and 28 species were identified. The ecological score of the benthic macroinvertebrate community was 15 inside the reservoir (St. 2). Micropterus salmoides, an invasive alien species, was determined to be the subdominant fish species based on the number of captures, and the presence of the invasive species, Sicyos angulatus L. and Paspalum distichum L. was confirmed among the land flora.
기후변화로 인한 수자원 전망은 배출 시나리오, 전지구적 순환모형, 상세화 기법, 수문 모형 등 여러 전망 단계를 거쳐 이루어지며, 각 단계는 수자 원 전망의 총 불확실성의 원천이 된다. 몇몇 연구를 통해 개별 전망 단계의 총 불확실성에 대한 상대적인 기여를 계량화하는 방법이 제안되었으며며, 이러한 분석을 불확실성 분해라고 한다. 불확실성 분해 분석은 큰 불확실성을 발생시키는 단계를 진단하고, 이를 반영한 불확실성 저감 계획을 수립할 수 있게 한다. 전망 단계 간의 교호작용은 불확실성 분해 시 고려되어야 하는 중요한 문제 중 하나이다. 본 연구는 교호작용 효과로 인한 불 확실성을 계량화하고 이를 불확실성 분해에 반영하는 새로운 방법을 제안한다. 제안한 방법은 전망 단계별 불확실성을 주효과와 교호작용 효과를 모두 고려하여 계량화함과 동시에 총 불확실성에서 개별 전망 단계가 차지하는 상대적인 비중을 제시할 수 있다는 장점이 있다. 제안한 방법을 충 주댐 유량 전망의 불확실성 분석에 적용하였다. 충주댐 유역의 불확실성 분석 결과 여름과 겨울 두 계절 모두에서 교호작용 효과의 불확실성은 주 효과의 불확실성에 비해 그 크기가 작은 것으로 나타났다. 교호작용 효과를 고려하여 불확실성을 분해한 결과 배출 시나리오, 전지구적 순환모형, 상세화 기법, 수문 모형의 네 단계 중 여름철은 전지구적 순환모형의 불확실성이, 겨울철은 상세화 기법의 불확실성이 가장 큰 것으로 분석되었다.
The aim of this study is to delve deeper into the online brand community study. This study tests (a) the effects of online brand community on its outcomes, (b) the impact of value creation practice construct as a whole, (c) the effects of value creating practice construct on the two types of loyalty, loyalty toward the brand and the community. Participants of this study (N=353) are members of four types of online brand communities (e.g., business-to-consumer virtual product support community, firm-hosted online community, user-generated online community, peer-to-peer problem-solving community, and social media based brand community). Data were collected online using Amazon Mechanical Turk from April 10, 2016 to May 10, 2016. The data were analyzed through structural equations modeling using AMOS 20. The three community markers (e.g., consciousness of kind, rituals and traditions, and moral responsibility) and the four value creation practices (e.g., social networking, impression management, community engagement, and brand use) are proved to be significant indicators of online brand community and value creation practice constructs, respectively. Test results showed that strong and effective online brand communities generate value creation practices, and value creation practices enhance brand loyalty. The mediating effects of community loyalty between value creation practices and brand loyalty were revealed.
Purpose – For small and medium sized firms, CEO characteristics are main factor influencing firms’ prosperity as well as performance. So it is quite natural that many people are interested in factors of CEO that matters. In this research, CEO characteristics in terms of capabilities and skill or special knowledge necessary to run the business are invested for manufacturing firms. Precedent studies reveal that CEO characteristics such as psychological factors including desire to succeed, tendency to take risks, personal factors including age, year of running business, and task related factors including managing capability, communication skills, network influence firm performance for manufacturing firms. However, these studies simply verify whether or not those factors affect firm’s managing performance. This study, however, goes further to investigate how is the affecting process from CEO’s capabilities and organization characteristics to firm’s core competence, and from core competence to advantages, and from advantages to managing performance.
Research design, data, and methodology – We make a questionnaire and surveyed manufacturing firm CEO’s in Gyeonggi-do area. General characteristics analysis, factor analysis, regression analysis, and control effect analysis was conducted. SPSS 2.0 Win, version was used.
Results – The CEO characteristics including basic capability, task capability, leadership, and organization characteristics affect core competence at the statistically significant level. And, core competence affect both price advantage and differentiation advantage at the significant level. Some unique finding is that while differentiation advantage affects both financial achievement and non-financial achievement, price advantage does not affect both financial and non-financial achievement. And firm characteristics mainly measured by CEO characteristics of skills has control effects on the trace from core competence to price advantage.
Conclusions – For small and medium sized firms CEO characteristics is the most important factor influencing firm’s prosperity. For manufacturing firms, whether CEO has the skill or special knowledge to run the firm is critical factor. The study results show that CEO’s for manufacturing firms put importance on price and price advantage which seems to be familiar to them. However, the price advantage does not influential to financial and non-financial achievement. This result suggests that small and medium sized manufacturing firms’ CEO’s should make effort to improve other aspects of advantages to be more competitive.
With the paramount importance of key account management in business-to-business relationship, today companies are using this approach as a strategic weapon in their selling efforts targeted at the most important customers to solve their complex requirements with special treatment that eventually ensures both parties’ financial and nonfinancial objectives. The aim of this paper is to investigate the level of key account management performance among the export-oriented readymade garments companies in Bangladesh with regards to company’s experience in business, size of the company and key account serving capacity of the company. Using a questionnaire, data from 112 readymade garments companies in Bangladesh were collected and analyzed using descriptive analysis and ANOVA to test the level of key account management performance. Results show that the level of key account management performance by the garments companies did not vary by the company’s experience in business and size of the company respectively. In contrast, the level of key account management performance was found to be different concerning high, medium, and low customer service capacity. Apparently, companies with big number of customers show better performance than companies with small number of customer. Implications for this study are discussed along with suggestions for future research avenues.
The study is aimed at investigating the main factors that affect the interest rate yields, in the long-term. In addition, the study surveys the theories and literature relating to the determinants of interest rate. The importance of which is essential not only for governments, but also for banks and corporate financial risk management decisions, including risk exposures in banks and capital markets. Interest rate influences corporate profit as well as growth. For this purpose, the study examines the impact of budget deficit, risk-free rate, capital inflows, money supply and business cycles on real interest rate in Jordan. These factors are based upon well-established theories and straightforward practical view as interest rate determinants. Using data for (1990-2015), the study employed Johansen’s co-integrating test, which takes into consideration the long-term unsynchronized relationships. The data is tested for normality, symmetric correlations, covariance diagonal and unit root. The results show that the government budget deficit, short-term risk-free interest rate, capital inflows, money supply and business cycle are long-term determinants of the real interest rate in Jordan. The coefficients of government budget deficit, short-term risk-free rate, money supply and business cycle all are inversely affecting the real interest rate, while capital inflows has a positive impact on the real interest rate.
국내의 하천에는 많은 수의 보가 설치되어 있으며, 이러한 특성은 국외에서는 흔하지 않은 편이다. 흐름이 보와 같은 구조물을 통과하는 경우에는 불연속 흐름이 발생하게 되며, 수치모의 측면에서는 흐름항과 생성항의 균형 등의 문제로 수치적 안정성에 많은 영향을 준다. 이러한 문제점을 해결하기 위해서 경험식이나 해석기법의 단순화 등에 의존해 왔으며, 최근에 들어서는 보다 정확한 수치해석기법을 이용하려는 연구가 꾸준히 수행 되고 있다. K-River는 국내의 하천 특성을 반영하고, 불연속 흐름을 보다 정확히 계산하기 위한 목적으로 개발되었다. K-River의 검증을 위하여 1) 하상융기가 존재하는 개수로 수치실험 모의, 2) 도수현상 실내실험 모의, 3) 실제 하천의 수문 사상 모의를 수행하였다. 모든 모의에서 해석해 및 관측치와 유사한 결과를 모의하여 K-River의 적용성을 검증하였다.
In this study, water quality data of eight main sites in the Geumho River watershed were collected and analyzed for long-term changes in water quality over the period from 2005 to 2015. The results showed that BOD concentration was gradually improved by the Total Maximum Daily Load (TMDL), stages 1 and 2. Recently, a tendency of increasing BOD concentration was observed in the downstream section of the river. The concentration of COD was analyzed to be contaminated throughout the water system regardless of the water quality improvement project, and the TN concentration tended to increase in the midstream of the river from 2013. The TP concentration has clearly decreased from 2012 after the second stage of TMDL. For the statistical analysis of PCA ordination, monthly water qualities (pH, DO, Electrical Conductivity (EC), Water Temperature (WT), BOD, COD, TN, TP, TOC, and SS) and flow rate data for 5 years from 2012 to 2016 were used. Seasonally the Geumho River showed an increase in the TN concentration at point sources during the dry season (December to February). TP showed the effect of non-point sources in the summer, because rainfall has caused a rise in flow rate in the upstream. Besides, the origin of pollution source was changed from non-point sources with BOD, COD, and TOC.
본 연구에서는 적응적 분할격자기반 2차원 침수해석모형 K-Flood를 개발하였다. 분할격자기법은 흐름 특성을 기반으로 격자를 분할하여 흐름영역과 비흐름영역으로 구분하는 격자생성기법이며, 분할격자기법과 격자세분화기법을 동시에 활용하면 매우 적은 수의 격자로 복잡한 형상의 흐름 영역을 표현할 수 있어 효율적인 모의가 가능하다. 특히 최근 도시홍수에 대해 매우 정밀한 해상도의 자료와 격자를 이용하여 보다 정확한 침수해석 또는 예보를 하고자 하는 시도가 늘어나고 있으며, K-Flood는 이러한 복잡한 흐름영역의 계산 시 적응적 분할격자를 활용하여 효율적인 격자생성이 가능하다. 공간 및 시간에 대해 2차 정확도의 유한체적 수치해법이 적용되었다. K-Flood의 검증을 위해 2차원 침수해석모형의 검증에 널리 사용되고 있는 1) 원형 실린더에 의한 충격파 반사 모의, 2) 도시홍수실험 모의, 3) Malpasset 댐붕괴 모의를 수행하였다. 모든 모의에서 관측자료 및 과거의 모의결과와 비교하여 성공적으로 K-Flood의 성능을 검증하였다.
양송이 유통에 적합한 필름 포장방법 연구를 위해 저장온도 및 필름 산소투과도에 따른 양송이 품질변화를 분석하였다. 실험에 이용된 필름은 PVC와 OPP(OTR 1,000, 6,000, 10,000, 20,000 mL/m2/day/atm)이고 저장 온도는 4, 8, 12, 20℃로 설정하였다. 분석 결과, 중량감소율은 대조구, PVC, OPP 순으로 높았다. 갓 개열은 온도 별로 결과가 다르게 나타나 8℃ 이상에서 필름 처리구의 갓 개열 억제 효과가 나타났고 12℃에서는 필름 내부의 산소 농도가 낮을수록 억제 효과가 높은 경향이었다. 필름 중 OPP20000은 20℃에서 갓 개열 억제 효과가 나타나지 않았다. 대 신장은 모든 온도에서 전반적으로 필름 처리구가 대조구에 비해 억제되었으나 예외적으로 OPP20000은 대 신장이 대조구보다 오히려 촉진되는 결과였다. 조직의 경도는 필름 중 OPP1000이 다른 처리구에 비해 유의하게 높았다. 버섯의 내외부 색도는 모두 OPP 필름의 버섯이 대조구와 PVC에 비해 색 변화가 큰 경향이었다. 전반적으로 OPP는 중량감소, 갓 개열, 대 신장, 조직 경도에서 대조구에 비해 품질이 유지되는 효과가 있었으나 온도 및 산소투과도에 따라 효과의 차이가 있었고 OPP20000은 조직 생장 억제와 관련된 효과가 나타나지 않았다. OPP1000과 OPP6000은 OPP 중 조직 생장 억제에 가장 효과적이었으나 내부 단면에서 조직손상 및 수침 현상과 같은 장해가 나타났다. 한편 PVC 필름은 중량감소, 갓 개열, 대 신장이 대조구에 비해 변화가 적었고 내외부 갈변은 OPP보다 변화가 적어 전반적인 품질변화가 적은 것으로 분석되었다.