• Title/Summary/Keyword: repeated impact

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Trading Strategies in Bulk Shipping: the Application of Artificial Neural Networks

  • Yun, Hee-Sung;Lim, Sang-Seop;Lee, Ki-Hwan
    • Journal of Navigation and Port Research
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    • v.40 no.5
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    • pp.337-343
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    • 2016
  • The core decisions of bulk shipping businesses can be summarized as the timing and the choice of period for which carrying capacity is traded. In particular, frequent decisions to trade freight either with repeated spot transactions or with a one-off long-term deal critically impact business performance. Even though a variety of freight trading strategies can be employed to facilitate the decisions, chartering practitioners have not been active in utilizing these strategies, and academic research has rarely proposed applicable solutions. The specific properties of freight as a tradable commodity are not properly reflected in existing studies, and limitations have been reported in their application to the real world. This research focused on the establishment of applicable freight trading strategies by taking into account two properties of freight: time perishability and term-dependant pricing. In addition to traditional trading strategies, artificial neural networks were applied for the first time to the test of freight trading strategies. The performances of the trading strategies were measured and compared to produce a remarkable outperformance of the ANN. This research is expected to make a significant contribution to chartering practices by enhancing the quality of chartering decisions and eventually enabling the effective management of freight rate risk. In addition to methodological expansion, the result will propose a way to approach the controversial issue of freight market efficiency.

Development of Empowerment Program for Persons with Chronic Mental Illness and Evaluation of Impact (만성 정신질환을 가진 환자를 위한 임파워먼트프로그램 개발 및 효과)

  • Kim, Mijung;Lee, Kyunghee
    • Journal of Korean Academy of Nursing
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    • v.45 no.6
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    • pp.834-845
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    • 2015
  • Purpose: This study was done to develop an empowerment program for people with chronic mental illness and to analyze effects of the program on level of empowerment. Methods: The research was conducted using a nonequivalent control group pretest-posttest design. Participants were 37 people with chronic mental illness (experimental group: 18, control group: 19). The empowerment program was provided for 8 weeks (15 sessions). Data were collected between July 21 and October 17, 2014. Data were analyzed using Chi-square, Fisher's exact test, Sapiro-wilk test, and Repeated measure ANOVA with SPSS/WIN 18.0. Results: Quantitative results show that self-efficacy, interpersonal relationships, attitudes in the workplace, occupational performance capacity, and levels of empowered execute were significantly better in the experimental group compared to the control group. Conclusion: Study findings indicate that this empowerment program for persons with chronic mental illness is effective for improving self efficacy, interpersonal skills, attitudes in the workplace, occupational performance capacity, levels of empowered execute.

Determination of Optimum Threshold for Accuracy of People-counting System Based on Motion Detection

  • Ryu, Hanseul;Song, Junho;Lee, Boram;Lee, Kiyoung
    • Journal of Environmental Health Sciences
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    • v.41 no.5
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    • pp.299-304
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    • 2015
  • Objectives: A people-counting system measures real-time occupancy through motion detection. Accurate people-counting can be used to calculate suitable ventilation demands. This study determined the optimum motion threshold for a people-counting system. Methods: In a closed room with two occupants moving constantly, different thresholds were tested for the accuracy of a people-counting system. The experiments were conducted at 150, 300, 450 and 600 lux. These levels of brightness included the illumination levels of most public indoor areas. The experiments were repeated with three types of clothing coloration. Results: Overall, a threshold of 16 provided the lowest mean error percentage for the people-counting system. Brightness and clothing color did not have a significant impact on the results. Conclusion: A people-counting system could be used with threshold of 16 for most indoor environments.

The Impact of Vibration Exercises on Shoulder Muscle Thickness

  • Jeong, Jin-Gyu;Park, Jae-Cheol
    • The Journal of Korean Physical Therapy
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    • v.30 no.4
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    • pp.117-122
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    • 2018
  • Purpose: The objective of this study was to examine the effect of vibration exercises generated from an $XCO^{(R)}$ trainer on supraspinatus, infraspinatus, teres minor, and deltoid muscle thickness. Methods: Thirty subjects were evenly divided into two groups. Muscle thickness was measured by a sonogram prior to the study, and at three and six weeks after the intervention. Changes in muscle thickness were analyzed using a repeated measure analysis of variance (ANOVA). The significance level for the statistical test was set at ${\alpha}=0.05$. Results: A statistically significant differences in timing, interactions between timing and the groups, and between-group changes were demonstrated for supraspinatus muscle thickness (p<0.05). A similar finding was reported for infraspinatus, teres minor, and deltoid muscles with regard to the interactions between timing and the groups (p<0.05), although the between-group change did not reach statistical significance (p>0.05). Conclusion: Significant changes were observed in the thickness of the supraspinatus, infraspinatus, teres minor, and deltoid muscles, owing to the use of vibration exercises generated from an $XCO^{(R)}$ trainer. These findings can be used as a foundation for future studies on rehabilitation training.

A Study on Statistical Analysis of Load Carrying Capacity of Steel Bridges (강도로교의 내하력 통계분석과 해석에 관한 연구)

  • Chang, Dong Il;Lee, Hee Hyun;Eom, Yeong Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.8 no.1
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    • pp.41-48
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    • 1988
  • Fatigue phenomena usually occur in the structures such as bridges subjected to repeated loading with increasing service year. Especially, applied stresses happen to approach to design values due to rapid increase of traffic volume and vehicle weight, so it gives serious effects to the stability of bridges. Therefore, in this paper, the data for load carrying capacity of bridges obtained from field tests were analysed statistically to investigate bridge behaviour and a basic approach to estimate the impact factor was proposed after a comparison war made between field-test data and the calculated values obtained by using matrix structural analysis method.

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Comparison of the Impact of Breathing Strengthening Exercises and Balloon Blowing Training on the Pulmonary Function of Elderly Smokers

  • Jun, Hyun ju;Lim, Sang Wan;Kim, Ki Jong
    • Journal of International Academy of Physical Therapy Research
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    • v.6 no.2
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    • pp.878-883
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    • 2015
  • The purpose of this study compared the ability of feedback breathing training (FBT) and balloon blowing training to enhance the breathing of elderly people. The subjects were randomly and evenly divided into a feedback breathing training group (FBTG) and a balloon blowing training group (BBTG). Each group trained 3 times a week for 4 weeks, with the training suspended during the last 2 weeks. Pulmonary function measurements were obtained before the test and 2, 4 and 6 weeks after the test: forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FEV1/FVC, peak expiratory flow (PEF) and vital capacity (VC). A repeated-measures ANOVA was conducted for the significance test. The FBT resulted in a significant increase in the FVC, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. The BBT resulted in a significant increase in the FVC, FEV1, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. In conclusion, An at home breathing rehabilitation program, in addition to balloon blowing, could increase the breathing performance of elderly people.

Acoustic Analysis of Voice Change According to Extent of Thyroidectomy (갑상선 수술범위에 따른 음성의 음향적 분석)

  • Kang, Young Ae;Koo, Bon Seok
    • Phonetics and Speech Sciences
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    • v.7 no.4
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    • pp.77-83
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    • 2015
  • Voice complication without the laryngeal nerve injury can occur after thyroidectomy. The purpose of this study is to investigate voice changes according to extent of thyroidectomy with acoustic analysis. Thirty-five female patients with papillary thyroid carcinoma took voice evaluation at before and 1 month, and 3 months after thyroidectomy. Acoustic analysis parameters were speaking fundamental frequency(SFF), min $F_0$, max $F_0$, dynamic range $F_0$, jitter, shimmer, noise-to-harmonic ratio(NHR), and Cepstral prominence peak(CPP). Repeated-measured analysis of variance was applied. Time-related voice changes showed significant differences in all parameters except NHR. At 1 month after surgery, voice quality was worse and pitch was decreasing, but voice quality and pitch were improving at 3-month follow-up. Voice changes according to the extent of surgery were in SFF, max $F_0$, and dynamic range $F_0$. Time by surgery-related voice change existed only in min $F_0$. The result showed that the severity of voice complication depended on the extend of thyroidectomy which had a negative impact on $F_0$-related parameters. The deterioration of voice quality at 1 month after thyroidectomy may be affected by the loss of thyroid hormone in the blood. The descent of $F_0$-related parameters may be impacted by laryngeal fixation of surgical site adhesion.

Auction Experience, Category Knowledge and Trust in eBay Stamp Auctions

  • Kim, Tae-Ha;Jaju, Anupam
    • Asia pacific journal of information systems
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    • v.20 no.3
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    • pp.33-49
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    • 2010
  • We empirically examine the impact of online auction knowledge and category-specific knowledge on the final price of online auctions. Specifically, we question how the relationship between buying and selling experiences affects the final prices of online auctions. Related to the trust between buyers and sellers, we examine the multiple interactions between a buyer-seller pairand aim to identify how these repeated transactions influence the final price. To contrast these effects with other product related factors, we focus on so called 'common value' auctions of vintage stamps on eBay, in which the ex-post value of the product is the same among participating agents’ perceived value. Online auction of stamps provides a representative setting to examine the relationship between market experience and the auction participation behavior in the common value auction, as it provides the book value of stamp as well as price variation across individual buyers with different expertise levels. Our analysis of over 3000 stamps auctions on eBay indicates a significantly high frequency of buyer-seller (pair) interactions, thus suggesting a 'relationship view' of auctions. The work validates five hypotheses derived from the existing theory in economics, marketing, and information systems. Through the common-value auction data, we find that seller's online auction experience and category-specific experience favor sellers by increasing the final price. However, buyer's online auction experience does not affect the final price, but buyer's category-specific experience favors buyers by decreasing the final price. We find that the trust between two trading parties increases the final price.

Development of a Community-Based Approach to Opisthorchiasis Control

  • Duangsong, Rujira;Promthet, Supannee;Thaewnongiew, Kesorn
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.7039-7043
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    • 2013
  • A liver fluke, Opisthorchis viverrrini (OV), is the major cause of the high incidence of cholangiocarcinoma in North-eastern Thailand. The prevalence of OV infection remains high in various parts of the country, especially in wetland rural areas where a large proportion of the community work in agriculture and continue the traditional practice of eating raw or uncooked cyprinoid fish products. The national control program seems to have had little impact in many of these areas, and it has been difficult to make precise assessments of the overall effectiveness of the program. Therefore there is a need for a community-based approach to prevent infection with the parasite, ideally involving as many players as possible. Here we document an attempt to assess the best means to prevention on the basis of a community intervention in three villages in north-east Thailand, with participation of representatives of Health Promotion Hospitals of the Ministry of Public Health with dedicated staff, but also school teachers, independent government sponsored village health volunteers, and housewives responsible for cooking and diet selection. An action plan was followed, allowing detailed discussions of practical proposals, their introduction and then repeated reflection and further proposals at the individual village level.

Natural wind impact analysis of transiting test method to measure wind pressure coefficients

  • Liu, Lulu;Li, Shengli;Guo, Pan;Wang, Xidong
    • Wind and Structures
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    • v.30 no.2
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    • pp.199-210
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    • 2020
  • Building wind pressure coefficient transiting test is a new method to test the building wind pressure coefficient by using the wind generated by a moving vehicle, which is susceptible to natural wind and other factors. In this paper, the Commonwealth Advisory Aeronautical Research Council standard model with a scale ratio of 1:300 is used as the test object, and the wind pressure coefficient transiting test is repeated under different natural wind conditions to study the influence of natural wind. Natural wind is measured by an ultrasonic anemometer at a fixed location. All building wind pressure coefficient transiting tests meet the test conditions, and the vehicle's driving speed is 72 km/h. The mean wind pressure coefficient, the fluctuating wind pressure coefficient, and the correlation coefficient of wind pressure are used to describe the influence of natural wind on the building wind pressure coefficient transiting test qualitatively and quantitatively. Some rules, which can also help subsequent transiting tests, are also summarized.