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A Study on Decision Making Factors Affecting Bank Performance: Focusing on US Banks (은행의 성과에 영향을 미치는 의사결정 요인에 관한 연구: 미국은행을 중심으로)

  • Ik-Sung Choi;Jae-Sung Kim
    • Journal of Industrial Convergence
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    • v.22 no.2
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    • pp.1-12
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    • 2024
  • This study investigates what decisions have an impact on bank performance. A panel regression analysis was conducted using data from the financial statements of banks located in the United States from 2013 to 2022, and the effects of explanatory variables were examined through hierarchical panel regression analysis divided into financial decision-making and management decision-making. In addition, by analyzing performance separately from the creditor and shareholder perspectives (hereinafter referred to as overall) and from the shareholder perspective alone, it suggests which elements should be utilized and how to improve performance from each perspective. When a panel regression analysis was performed using only liquidity and stability, dependency on deposits and the interest coverage ratio had a statistically significant impact from the perspective of overall performance, and the debt ratio also had a statistically significant impact from the perspective of shareholder performance. When adding non-technical factors, only the labor cost ratio among non-technical factors was found to be statistically significant from the overall performance perspective, and although the non-technical factors were not statistically significant from the shareholder performance perspective, the cash ratio was found to have a statistically significant impact. Lastly, when adding technical innovation elements, the intangible asset ratio was not statistically significant from the overall performance perspective, but was significant from the shareholder performance perspective. The significance and implications of this study are that there are differences in factors that can affect the performance of overall or shareholder and that various decision-making factors can affect a bank's performance.

Endoscopic radiofrequency Stretta therapy reduces proton pump inhibitor dependency and the need for anti-reflux surgery for refractory gastroesophageal reflux disease

  • Abraham Joel;Alakh Konjengbam;Yirupaiahgari Viswanath;Georgios Kourounis;Emily Hammond;Helen Frank;Shivani Kuttuva;Simon Mbarushimana;Hena Hidayat;Srivishnu Thulasiraman
    • Clinical Endoscopy
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    • v.57 no.1
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    • pp.58-64
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    • 2024
  • Background/Aims: Radiofrequency treatment of the gastroesophageal junction using the Stretta procedure for treating gastroesophageal reflux disease (GERD) is observed to improve the symptoms and proton pump inhibitor (PPI) dependence and reduce the need for anti-reflux operations. As one of the largest studies in Europe, we evaluated the clinical outcomes of Stretta in patients with medically refractory GERD. Methods: A tertiary UK center evaluated all patients with refractory GERD who underwent Stretta between 2014 and 2022. Patients and primary care professionals were contacted to obtain information regarding the initiation of PPI and reintervention after Stretta. Results: Of the 195 patients (median age, 55 years; 116 women [59.5%]) who underwent Stretta, PPI-free period (PFP) data were available for 144 (73.8%) patients. Overall, 66 patients (45.8%) did not receive PPI after a median follow-up of 55 months. Six patients (3.1%) underwent further interventions. The median PFP after Stretta was 41 months. There was a significant negative correlation between PFP and age (p=0.007), with no differences between sexes (p=0.96). Patients younger than 55 years of age had a longer PFP than their older counterparts (p=0.005). Younger males had a significantly longer PFP than older males (p=0.021). However, this was not observed in the female cohort (p=0.09) or between the younger men and women (p=0.66). Conclusions: Our findings suggest that Stretta is a safe and feasible option for treating refractory GERD, especially in younger patients. It prevents further anti-reflux interventions in most patients and increases the lead-time to surgery in patients with refractory GERD.

A Study on the Correlation Analysis between International Oil Prices and the 4 Major Shipping Markets of Bulk Carrier (국제 유가와 벌크선 4대 해운 시장의 상관관계 분석에 관한 연구)

  • Ryu, Won-Hyeong;Nam, Hyung-Sik
    • Journal of Korea Port Economic Association
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    • v.39 no.4
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    • pp.43-65
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    • 2023
  • Recently, with the increasing international interest on environmental issues, efforts have been made to reduce greenhouse gas emissions due to ship fuel, however, the dependence on fossil fuel is expected to continue for a while. Since fuel costs account for a high portion of the total operating cost of a ship, it is necessary to analyze the influence of oil prices on the shipping markets. The purpose of this study is to evaluate the relationship between the international oil prices and the four major shipping markets for bulk carriers. This study employed WTI as the oil price variable while monthly data from 2017 to 2020 from the four major shipping markets by classifying freight rates, charter rates, newbuilding prices, and secondhand prices were also considered in multiple ship sizes of capesize, panamax, supramax, and handysize. Firstly, the results of the correlation analysis using the VAR model indicate that changes in international oil prices have a statistically positive (+) significant effect on BCIS only in the second time lag, on BSIS at all lags, and on BHIS only in the first staggered period. Secondly, as a result of correlation analysis using the VECM model, in the case of BPIC, BHIC, BCIN, and BHIR, the cointegration coefficient value has a negative (-) significant effect at the 5% significance level in the cointegration relationship with international oil prices. Further, in the case of the dynamic correlation, the increase in oil price in the first period of the lag leads to a decrease in the BCIN newbuilding prices while the increase in the oil price in the first and second period in the lag leads to a decrease in the BHIR used ship prices.

A Reflectance Normalization Via BRDF Model for the Korean Vegetation using MODIS 250m Data (한반도 식생에 대한 MODIS 250m 자료의 BRDF 효과에 대한 반사도 정규화)

  • Yeom, Jong-Min;Han, Kyung-Soo;Kim, Young-Seup
    • Korean Journal of Remote Sensing
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    • v.21 no.6
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    • pp.445-456
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    • 2005
  • The land surface parameters should be determined with sufficient accuracy, because these play an important role in climate change near the ground. As the surface reflectance presents strong anisotropy, off-nadir viewing results a strong dependency of observations on the Sun - target - sensor geometry. They contribute to the random noise which is produced by surface angular effects. The principal objective of the study is to provide a database of accurate surface reflectance eliminated the angular effects from MODIS 250m reflective channel data over Korea. The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor has provided visible and near infrared channel reflectance at 250m resolution on a daily basis. The successive analytic processing steps were firstly performed on a per-pixel basis to remove cloudy pixels. And for the geometric distortion, the correction process were performed by the nearest neighbor resampling using 2nd-order polynomial obtained from the geolocation information of MODIS Data set. In order to correct the surface anisotropy effects, this paper attempted the semiempirical kernel-driven Bi- directional Reflectance Distribution Function(BRDF) model. The algorithm yields an inversion of the kernel-driven model to the angular components, such as viewing zenith angle, solar zenith angle, viewing azimuth angle, solar azimuth angle from reflectance observed by satellite. First we consider sets of the model observations comprised with a 31-day period to perform the BRDF model. In the next step, Nadir view reflectance normalization is carried out through the modification of the angular components, separated by BRDF model for each spectral band and each pixel. Modeled reflectance values show a good agreement with measured reflectance values and their RMSE(Root Mean Square Error) was totally about 0.01(maximum=0.03). Finally, we provide a normalized surface reflectance database consisted of 36 images for 2001 over Korea.

Characteristics of Anion Exchange Measured by the Rate of Hemolysis in Human Erythrocyte (사람의 적혈구에서 용혈성을 이용하여 측정한 음이온 교환특성)

  • Woo, Jae-Suk;Kim, Yong-Keun;Hwang, Il-Yong
    • The Korean Journal of Physiology
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    • v.20 no.2
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    • pp.218-224
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    • 1986
  • The characteristics of anion exchange with internal HCO3(orOH) was studied by determining the time course of hemolysis in isoosmotic ammonium salt solution in human erythrocytes. The effects of inhibitors, pH and temperature on the exchange between internal HCO3(orOH) and external Cl were observed and the permeabilities of various organic and inorganic anions were also measured. The results were compared with data previously reported from the experiments using radioisotopes. The results are as follows; 1) SITS H2DIDS and furosemide inhibited the hemolysis of erythrocytes in isoosmotic NH4Cl solution in a dose·dependent manner, and the concentrations for lengthening twice the time for halfhemloysis(t1/2)were2.3×107,1.3×107and2.5×105M, respectively. 2) Acetazolamide also shifted the time-dependent hemolytic curve to the right in a dose-dependent manner, and the concentrations for lengthening twice t1/2was2.4×105M. 3) The time-dependent hemolysis was delayed by decreasing pH from 7.0 to 6.2, but w·as not affected by the change of pH in the range of 7.0 to 8.2. 4) The time for halfhemloysis(t1/2) showed a temperature-dependency and Arrhenius plot exhibited a break point at 20C. The apparent activation energy calculated from this plot was 18.1 kcal/mol between 2C20C and 11.2 kcal/mol between 20C37C, respectively. 5) The apparent permeabilities of various inorganic anions based on t1/2 were in the order of Cl>NO3>SCN>SO42>SSO32>HPO42. which was similar with the previous reports based on the experiment using radioisotopes. The results Obtained from this study are comparable with the previous data reported from the experiments using radioisotopes. This indicates that the hemolysis of erythrocytes in isoosmotic ammonium salt solution can be used as a simple and good method for the study of anion exchange in erythrocyte membrane.

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The Clinical Characteristics Between the Positional Obstructive Sleep Apnea Patients with the Non-positional Obstructive Sleep Apnea Patients (체위성 폐쇄성수면무호흡 환자와 비체위성 폐쇄성수면무호흡환자의 임상적 특징 고찰)

  • Kang, Hyeon-Hui;Kang, Ji-Young;Lee, Sang-Haak;Moon, Hwa-Sik
    • Sleep Medicine and Psychophysiology
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    • v.19 no.1
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    • pp.22-26
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    • 2012
  • Objectives: The percentage of positional sleep apnea in obstructive sleep apnea (OSA) varies in different reports from 9% to 60%. If there is a positional dependency in patients with OSA, positional therapy alone could be successful in treating about 50% of all OSA cases. The aim of this report is to compare anthropomorphic and polysomnographic data between the positional sleep apnea group and non-positional sleep apnea group with OSA whose conditions were diagnosed in our sleep clinic. Methods: This is a retrospective study of anthropomorphic and polysomnographic data of patients with OSA who was performed a nocturnal polysomnography. Positional sleep apnea was defined as having a supine apnea-hypopnea index (AHI) of twice or more compared to the AHI in the non-supine position. The patients were divided in the positional sleep apnea group and the non-positional sleep apnea group. Results: In 101 patients with OSA, 81 were male, and the mean age was 49.2±11.9 years. Seventy-six (75.2%) were diagnosed as the positional sleep apnea. Waist to hip ratio and body mass index (BMI) were significantly higher in non-positional sleep apnea group. The frequency of severe OSA was significantly higher in this group. In the positional sleep apnea group, nocturnal sleep quality was better preserved, and consequently these patients were less sleepy during daytime. AHI was significantly lower and minimal arterial oxygen saturation during sleep was significantly higher in this group. Conclusion: The percentage of positional sleep apnea in OSA was 75.2%. AHI, BMI, and waist to hip ratio were lower in the positional sleep apnea group. These patients have less severe breathing abnormalities than the non-positional sleep apnea group in polysomnography.

An Ethnography of Child-Rearing Experiences of Korean Mothers Living on Koje Island (우리나라 어머니의 자녀 양육의 의미 - 거제지역을 대상으로 -)

  • Lee, Soo-Yeon
    • Women's Health Nursing
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    • v.7 no.4
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    • pp.518-535
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    • 2001
  • Nursing practices should be based on the understanding of human beings. In order to understand human beings, it is important to study the lifestyles and thoughts of people in their natural environment. In this sense, the cultural aspects of a society need to be studied for a culture-bound nursing service. Child care, which is an important element of nursing, is also strongly influenced by the culture of a society. Therefore, a cultural study is necessary to understand the child-rearing practices of any society. The major purpose of this dissertation is to provide basic foundations for developing a culture-based theory for nursing intervention through studying traditional cultural elements of child care in Korean society. The study examined child-rearing practices in a small village on Koje Island in the southern part of Korea. It utilized ethnographic methodologies including participatory observations and in-depth interviews. The study participants were 9 Korean mothers living on Koje Island. The average age was 52. The data were collected between July in 1998 and December in 1999. The average number of interviews per person was 7-8, and the duration of each interview was approximately 2 hours. The data were analyzed using the Spradley Analytical Method. The following 9 major child-rearing aspects of mothers on Koje Island were discovered as a result of the study: 1. Firstly, mothers on Koje Island were mostly concerned about the "Old Birth Goddess' Curse", especially during their child's early years. This concern was evidenced by their careful behavior when their child was very young and by their praying to the Old Birth Goddess not to be jealous of their babies. 2. Secondly, they wished their children to live a different and better life than themselves. It was represented by their strong motivation toward their children's education as well as their expectation for their children's success. In traditional Korean culture, Korean people think that the rise and fall of the household depend on their offsprings. Therefore, Korean mothers wish their children attain to a higher level of social status through education. 3. Third, mothers are concerned about their children's righteousness. Mothers on Koje island expect their children to live with discretion, justice, strength, respect, harmony, and to do their best in life. 4. Next was an 'anticipation of their children's happy marriage'. The attributes of this category were an 'anxiety about their children's married life', and 'an expectation of a good spouse for their children'. Because Korean people believe that only a son can continue the bloodline of a family, especially Korean mothers have a great concern of the possibility of their daughters not having a son after marriage. Also they have different expectations toward their daughter-in-laws than son-in-laws. 5. Korean mothers also derived their satisfaction from their son. It was characterized by 'excessive affection toward their son', 'dependency on their son', and 'being afraid of their married daughter having a girl like themselves'. Korean society has been a patriarchy. Therefore, a son is beloved as someone who will take care of his old parents, be in charge of ancestral rites, and provide a daughter-in-law who can conceive a son. 6. The sixth category concerned 'the differences in their expectations for their children'. The attributes in this category were 'different expectations depending on their children's gender', 'different expectations depending on their children's ability', and a 'great sympathy toward children with low abilities'. Korean mothers expect their son to become better than their daughter. 7. The seventh category was related to their 'roles in child-caring practices'. Traditionally a child was raised in an extended family system in Korea So it was not the sole duty of a mother to bring up the child. Korean mothers used to receive much help rasing children from their in-laws, and family members. On the other hand, many children grew up by themselves, because their mothers were very busy taking care of housework. Furthermore, many children also grew up in poverty. 8. Mothers also had issues related to 'conflicts in child rearing'. They were characterized by 'lack of understanding', 'rudeness of children', and 'giving vent to one's anger'. 9. Finally, mothers regretted not doing their best in child-rearing practices. It was characterized by a 'bitter feeling of repentance', 'feeling irritated', and 'feeling of unsatisfaction'.

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A Geographically Weighted Regression on the Effect of Regulation of Space Use on the Residential Land Price - Evidence from Jangyu New Town - (공간사용 규제가 택지가격에 미치는 영향에 대한 공간가중회귀분석 - 장유 신도시지역을 대상으로-)

  • Kang, Sun-Duk;Park, Sae-Woon;Jeong, Tae-Yun
    • Management & Information Systems Review
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    • v.37 no.3
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    • pp.27-47
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    • 2018
  • In this study, we examine how land use zoning affects the land price controlling other variables such as road-facing condition of the land, land form, land age after its development and land size. We employ geographically weighted regression analysis which reflects spatial dependency as methodology with a data sample of land transaction price data of Jangyu, a new town, in Korea. The results of our empirical analysis show that the respective coefficients of traditional regression and geographically weighted regression are not significantly different. However, after calculating Moran's Index with residuals of both OLS and GWR models, we find that Moran's Index of GWR decreases around 26% compared to that of OLS model, thus improving the problem of spatial autoregression of residuals considerably. Unlike our expectation, though, in both traditional regression and geographically weighted regression where residential exclusive area is used as a reference variable, the dummy variable of the residential land for both housing and shops shows a negative sign. This may be because the residential land for both housing and shops is usually located in the level area while the residential exclusive area is located at the foot of a mountain or on a gentle hill where the residents can have good quality air and scenery. Although the utility of the residential land for both housing and shops is higher than its counterpart's since it has higher floor area ratio, amenity which can be explained as high quality of air and scenery in this study seems to have higher impact in purchase of land for housing. On the other hand, land for neighbourhood living facility seems to be valued higher than any other land zonings used in this research since it has much higher floor area ratio than the two land zonings above and can have a building with up to 5 stories constructed on it. With regard to road-facing condition, land buyers seem to prefer land which faces a medium-width road as expected. Land facing a wide-width road may have some disadvantage in that it can be exposed to noise and exhaust gas from cars and that entrance may not be easy due to the high speed traffic of the road. In contrast, land facing a narrow road can be free of noise or fume from cars and have privacy protected while it has some inconvenience in that entrance may be blocked by cars parked in both sides of the narrow road. Finally, land age variable shows a negative sign, which means that the price of land declines over time. This may be because decline of the land price of Jangyu was bigger than that of other regions in Gimhae where Jangyu, a new town, also belong, during the global financial crisis of 2008.

Reliability Analysis on Firewater Supply Facilities based on the Probability Theory with Considering Common Cause Failures (소방수 공급설비에 대한 공통원인고장을 고려한 확률론적 신뢰도 분석)

  • Ko, Jae-Sun;Kim, Hyo
    • Fire Science and Engineering
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    • v.17 no.4
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    • pp.76-85
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    • 2003
  • In this study, we write down the definitions, their causes and the techniques of analysis as a theoretical consideration of common cause failures, and investigate the limitation and the importance of the common cause failures by applying to the analysis on the fire protection as a representative safety facility. As you can know in the reliability analysis, most impressive cause is the malfunctions of pumping operations; especially the common cause failure of two pumps is dominant. In other words, it is possible to assess system-reliability as twice as actual without CCF From these, CCF is extraordinarily important and the results are highly dependent on the CCF factor. And although it would increase with multiple installations, the reliability are not defined as linear with those multiplications. In addition, the differences in results due to the models for analysis are not significant, whereas the various sources of data produce highly different results. Therefore, we conclude that the reliabilities are dependent on the quality of the usable data much better than the variety of models. As a result, the basic and engineering device for the preventions of CCF of the multiple facilities is to design it as reliably as to design the fire-water pump. That is to say, we must assess those reliabilities using PFD whether they are appropriate to SIL (Safety Integrity Level) which is required for the reliability in SIS (Safety Instrumented System). The result of the analysis on the reliability of the fire-water supply with CCF shows that PFD is 3.80E-3, so that it cannot be said to be designed as safely as in the level of SIL5. However, without CCF, PFD is 1.82E-3 which means that they are designed as unsafely as before.

Predictive Clustering-based Collaborative Filtering Technique for Performance-Stability of Recommendation System (추천 시스템의 성능 안정성을 위한 예측적 군집화 기반 협업 필터링 기법)

  • Lee, O-Joun;You, Eun-Soon
    • Journal of Intelligence and Information Systems
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    • v.21 no.1
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    • pp.119-142
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    • 2015
  • With the explosive growth in the volume of information, Internet users are experiencing considerable difficulties in obtaining necessary information online. Against this backdrop, ever-greater importance is being placed on a recommender system that provides information catered to user preferences and tastes in an attempt to address issues associated with information overload. To this end, a number of techniques have been proposed, including content-based filtering (CBF), demographic filtering (DF) and collaborative filtering (CF). Among them, CBF and DF require external information and thus cannot be applied to a variety of domains. CF, on the other hand, is widely used since it is relatively free from the domain constraint. The CF technique is broadly classified into memory-based CF, model-based CF and hybrid CF. Model-based CF addresses the drawbacks of CF by considering the Bayesian model, clustering model or dependency network model. This filtering technique not only improves the sparsity and scalability issues but also boosts predictive performance. However, it involves expensive model-building and results in a tradeoff between performance and scalability. Such tradeoff is attributed to reduced coverage, which is a type of sparsity issues. In addition, expensive model-building may lead to performance instability since changes in the domain environment cannot be immediately incorporated into the model due to high costs involved. Cumulative changes in the domain environment that have failed to be reflected eventually undermine system performance. This study incorporates the Markov model of transition probabilities and the concept of fuzzy clustering with CBCF to propose predictive clustering-based CF (PCCF) that solves the issues of reduced coverage and of unstable performance. The method improves performance instability by tracking the changes in user preferences and bridging the gap between the static model and dynamic users. Furthermore, the issue of reduced coverage also improves by expanding the coverage based on transition probabilities and clustering probabilities. The proposed method consists of four processes. First, user preferences are normalized in preference clustering. Second, changes in user preferences are detected from review score entries during preference transition detection. Third, user propensities are normalized using patterns of changes (propensities) in user preferences in propensity clustering. Lastly, the preference prediction model is developed to predict user preferences for items during preference prediction. The proposed method has been validated by testing the robustness of performance instability and scalability-performance tradeoff. The initial test compared and analyzed the performance of individual recommender systems each enabled by IBCF, CBCF, ICFEC and PCCF under an environment where data sparsity had been minimized. The following test adjusted the optimal number of clusters in CBCF, ICFEC and PCCF for a comparative analysis of subsequent changes in the system performance. The test results revealed that the suggested method produced insignificant improvement in performance in comparison with the existing techniques. In addition, it failed to achieve significant improvement in the standard deviation that indicates the degree of data fluctuation. Notwithstanding, it resulted in marked improvement over the existing techniques in terms of range that indicates the level of performance fluctuation. The level of performance fluctuation before and after the model generation improved by 51.31% in the initial test. Then in the following test, there has been 36.05% improvement in the level of performance fluctuation driven by the changes in the number of clusters. This signifies that the proposed method, despite the slight performance improvement, clearly offers better performance stability compared to the existing techniques. Further research on this study will be directed toward enhancing the recommendation performance that failed to demonstrate significant improvement over the existing techniques. The future research will consider the introduction of a high-dimensional parameter-free clustering algorithm or deep learning-based model in order to improve performance in recommendations.