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An Empirical Study on the Influencing Factors of Perceived Job Performance in the Context of Enterprise Mobile Applications (업무성과에 영향을 주는 업무용 모바일 어플리케이션의 주요 요인에 관한 연구)

  • Chung, Sunghun;Kim, Kimin
    • Asia pacific journal of information systems
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    • v.24 no.1
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    • pp.31-50
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    • 2014
  • The ubiquitous accessibility of information through mobile devices has led to an increased mobility of workers from their fixed workplaces. Market researchers estimate that by 2016, 350 million workers will be using their smartphones for business purposes, and the use of smartphones will offer new business benefits. Enterprises are now adopting mobile technologies for numerous applications to increase their operational efficiency, improve their responsiveness and competitiveness, and cultivate their innovativeness. For these reasons, various organizational aspects concerning "mobile work" have received a great deal of recent attention. Moreover, many CIOs plan to allocate a considerable amount of their budgets mobile work environments. In particular, with the consumerization of information technology, enterprise mobile applications (EMA) have played a significant role in the explosive growth of mobile computing in the workplace, and even in improving sales for firms in this field. EMA can be defined as mobile technologies and role-based applications, as companies design them for specific roles and functions in organizations. Technically, EMA can be defined as business enterprise systems, including critical business functions that enable users to access enterprise systems via wireless mobile devices, such as smartphones or tablets. Specifically, EMA enables employees to have greater access to real-time information, and provides them with simple features and functionalities that are easy for them to complete specific tasks. While the impact of EMA on organizational workers' productivity has been given considerable attention in various literatures, relatively little research effort has been made to examine how EMA actually lead to users' job performance. In particular, we have a limited understanding of what the key antecedents are of such an EMA usage outcome. In this paper, we focus on employees' perceived job performance as the outcome of EMA use, which indicates the successful role of EMA with regard to employees' tasks. Thus, to develop a deeper understanding of the relationship among EMA, its environment, and employees' perceived job performance, we develop a comprehensive model that considers the perceived-fit between EMA and employees' tasks, satisfaction on EMA, and the organizational environment. With this model, we try to examine EMA to explain how job performance through EMA is revealed from both the task-technology fit for EMA and satisfaction on EMA, while also considering the antecedent factors for these constructs. The objectives of this study are to address the following research questions: (1) How can employees successfully manage EMA in order to enhance their perceived job performance? (2) What internal and/or external factors are important antecedents in increasing EMA users' satisfaction on MES and task-technology fit for EMA? (3) What are the impacts of organizational (e.g. organizational agility), and task-related antecedents (e.g., task mobility) on task-technology fit for EMA? (4) What are the impacts of internal (e.g., self-efficacy) and external antecedents (e.g., system reputation) for the habitual use of EMA? Based on a survey from 254 actual employees who use EMA in their workplace across industries, our results indicate that task-technology fit for EMA and satisfaction on EMA are positively associated with job performance. We also identify task mobility, organizational agility, and system accessibility that are found to be positively associated with task-technology fit for EMA. Further, we find that external factor, such as the reputation of EMA, and internal factor, such as self-efficacy for EMA that are found to be positively associated with the satisfaction of EMA. The present findings enable researchers and practitioners to understand the role of EMA, which facilitates organizational workers' efficient work processes, as well as the importance of task-technology fit for EMA. Our model provides a new set of antecedents and consequence variables for a TAM involving mobile applications. The research model also provides empirical evidence that EMA are important mobile services that positively influence individuals' performance. Our findings suggest that perceived organizational agility and task mobility do have a significant influence on task-technology fit for EMA usage through positive beliefs about EMA, that self-efficacy and system reputation can also influence individuals' satisfaction on EMA, and that these factors are important contingent factors for the impact of system satisfaction and perceived job performance. Our findings can help managers gauge the impact of EMA in terms of its contribution to job performance. Our results provide an explanation as to why many firms have recently adopted EMA for efficient business processes and productivity support. Our findings additionally suggest that the cognitive fit between task and technology can be an important requirement for the productivity support of EMA. Further, our study findings can help managers in formulating their strategies and building organizational culture that can affect employees perceived job performance. Managers, thus, can tailor their dependence on EMA as high or low, depending on their task's characteristics, to maximize the job performance in the workplace. Overall, this study strengthens our knowledge regarding the impact of mobile applications in organizational contexts, technology acceptance and the role of task characteristics. To conclude, we hope that our research inspires future studies exploring digital productivity in the workplace and/or taking the role of EMA into account for employee job performance.

Response Surface Methodology for Optimization of the Removal of Organic Matters in Eutrophic Waters by Korean Freshwater Bivalves (반응표면분석을 이용한 패류의 부영양수 유기물 제어능 연구)

  • Choi, Hwan-Seok;Nam, Gwi-Sook;Kim, Min-Seob;Shin, Hyun-Jae;Park, Myung-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.312-318
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    • 2014
  • This study was conducted to establish models of filtrating rate and production of feces of a native freshwater bivalve, Anodonta woodiana, on removal organic matters in eutrophic waters. Among the applied shell size (4.3~15.5 cm), the filtrating rate and production of feces of Anodonta woodiana was $0.08{\sim}0.86L\;g^{-1}\;h^{-1}$ (average $0.24L\;g^{-1}\;h^{-1}$), $0.00{\sim}11.10mg\;g^{-1}\;h^{-1}$ (average $0.94mg\;g^{-1}\;h^{-1}$), respectively. In two different water current (high $48Lh^{-1}$, low $24Lh^{-1}$), the filtrating rate of Chl-a was $0.02{\sim}0.10L\;g^{-1}\;d^{-1}$ (average $0.05L\;g^{-1}\;d^{-1}$), $0.02{\sim}0.11L\;g^{-1}\;d^{-1}$ (average $0.07L\;g^{-1}\;d^{-1}$) and the removal rate was 65.4%, 82.1%, respectively. Response surface methodology, with a central composite design comprising 3 levels and 2 variables, was used to identify the optimal removal condition of shell length, water current and filtrating rate or feces production by bivalves. The optimum removal conditions were found that had optimized $6.21L\;mussel^{-1}\;d^{-1}$ at shell length 14.3~15.6 and water current $22{\sim}30Lh^{-1}$. The optimal conditions of production of feces ($4.2mg\;g^{-1}\;d^{-1}$) by freshwater mussels were shell length 14.3~16.3 cm and water current $36{\sim}44Lh^{-1}$.

Factors Influencing the Regular Oral Check-Ups: Based on the Data of the 2014 Korea National Health and Nutrition Examination Survey (우리나라 경제활동자의 구강검진 수진 영향요인: 국민건강영양조사 제6기 2차년도(2014) 자료를 바탕으로)

  • Kim, Dong-Hwi;Seo, Young-Joon
    • Journal of dental hygiene science
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    • v.17 no.4
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    • pp.323-332
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    • 2017
  • This study aimed to investigate the factors influencing the decision on whether to receive regular oral check-ups among the national health insurance beneficiaries with income and aged over 20 years in Korea. This was a cross-sectional study, using the data from the 2014 6th Korea National Health and Nutrition Examination Survey (KNHANES VI-2), conducted by the Korea Centers for Disease Control and Prevention. The final sample included 2,843 subjects who participated in the health examination survey and oral check-ups. The IBM SPSS Statistics ver. 20.0 was used for the statistical analysis, based on the complex sampling design. The Rao-Scott chi-square test was used to verify the difference in the distribution of independent variables with regard to oral check-ups. The binary logistic regression analysis was used to determine the influencing factors. The ratio of beneficiaries who received oral check-ups was less than half of those who received medical examinations. The Rao-Scott chi-square test, revealed significant differences in the age group (p<0.05) of the predisposing factors, toothache within a year (p<0.001), untreated dental caries (p<0.001) of the need factors, personal income level (p<0.001), educational level (p<0.001), type of medical insurance (p<0.001), and private health insurance (p<0.01) of the enabling factors. In the binary logistic regression analysis, factors influencing oral check-ups were age group, personal income level, educational level, toothache within a year, and untreated dental caries. These findings show a variety of factors influencing the utilization of regular oral check-ups.

A Study on Research of Necessity and Practice of Contents of Clothing and Textiles Education (의생활 교육내용의 필요도와 실천도 조사 연구)

  • 박일록;이은희
    • Journal of Korean Home Economics Education Association
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    • v.15 no.3
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    • pp.89-103
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    • 2003
  • The purpose of this study was to investigate to relation of necessity and practice of contents of clothing and textiles education(classify them into four units, choice and dressing of clothes, textile and management of clothes, design and sewing of clothes, knitting and embroidery). Method of posing a questionnaire is adopted to obtain stochastic data required for pertinent analysis. This is the investigation of which 400 (high school students 204, university students 196) girl students located in Choongnam and Junrabookdo province. In this statistical analysis, SPSS 10.0 for Windows Program was utilized to calculate percentage, mean and standard deviation. Also, these materials were verified by t-test, One-way Anova, Pearson's correlation coefficient. The results of this research were as follows. First, girl students' necessity mean point were higher than practice mean point about the contents of clothing and textiles education. And necessity had a positive relationship with practices of contents of clothing and textiles education. Second, there was a significant difference in necessity and practice of contents of clothing and textiles education according to demographic variables. These results should be provide fundamental information for improving students' critical practice in their real life. Since this study has touched only limited research on the topic of clothing and textiles education, it is essential that further research covering a wider array of themes be done in the future. this study has touched only limited research on the topic of clothing and textiles education, it is essential that further research covering a wider array of themes be done in the future.

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The Effect of Positioning with Mechanically Ventilatory Acute Respitatory Failure Patients on Arterial Oxygen Partial Pressure and Alveolar-arterial Oxygen tension (인공호흡기를 부착한 급성 호흡부전 환자에서 폐병변 부위에 따른 체위적용이 동맥혈 가스분압 및 폐포동맥간 산소 분압차에 미치는 영향)

  • Hwang, Hee Joung;Park, Hye Ja
    • Korean Journal of Adult Nursing
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    • v.12 no.2
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    • pp.234-244
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    • 2000
  • It is widely recognized that manipulation of body position takes advantage of the influences of gravity for improving oxygenation. The study aims to determine the effects of positioning(supine, prone, right lateral decubitus and left lateral decubitus positions) applied to the mechanically ventilatory acute respiratory failure patients on arterial oxygen partial pressure($PaO_2$), alveolar arterial oxygen tension difference($AaDO_2$), mean aterial pressure, peak inspiratory pressure and plateau pressure. Thirty two acute respiratory failure patients admitted to the medical intensive care unit at Kangnam St. Mary's Hospital, The Catholic University of Korea from March 1997 to January 1998, were divided into three groups by radiographic evidence of unilateral or bilateral lung disease. In group 1 with dominant right lung disease were twelve subjects, group 2 with dominant left lung disease had eight subjects and group 3 had twelve subjects with bilateral lung disease. The variables were measured in 30 minutes after each position of supine, prone, good lung down lateral decubitus and sick lung down lateral decubitus position. The position order was done at random by Latin squre design. The results are as follows; 1) With group 1 patients, the $PaO_2$ in the left lateral decubitus and prone position were $126.8{\pm}30.8$ mmHg and $106.7{\pm}36.8$ mmHg, respectively(p=0.0001). 2) With group 2 patients, the $PaO_2$ in the prone and the right lateral decubitus position were $121.7{\pm}44.7$ mmHg and $118.5{\pm}31.7$ mmHg, respectively (p=0.0018). 3) With group 3 patients, the $PaO_2$ was $143.6{\pm}36.6$ mmHg in the prone position (p=0.0001). 4) With group 1 patients, the $AaDO_2$ in the left lateral decubitus and the right lateral decubitus position were $178.1{\pm}29.7$ mmHg and $233.1{\pm}24.4$ mmHg, respectively(p=0.0001). 5) With group 2 patients, the $AaDO_2$ in the prone and the left lateral decubitus postion were $184.0{\pm}39.5$ mmHg and $231.0{\pm}23.9$ mmHg, respectively(p=0.0019). 6) With group 3 patients, the $AaDO_2$ in the prone and the supine postion were $377.1{\pm}35.6$ mmHg and $435.7{\pm}13.1$ mmHg, respectively (p=0.0001). 7) There were no differences among the mean arterial pressure, peak inspiratory pressure and plateau pressure for each of the supine, prone, left lateral decubitus and right lateral decubitus position. The results suggest that oxygenation may improve in mechanically ventilatory patients with unilateral lung disease when the position is good lung dependent and prone, and patients with bilateral lung disease when the position is prone without any effects on the mean arterial pressure and airway pressure. It is suggested that body positions improve ventilation/perfusion matching and oxygenation need to be specified in patient care plans.

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A Study for the Evaluation of Container Modules; The Technology of Korean Container Tree Production Model (한국형 컨테이너 조경수 생산기술로서 컨테이너 모듈의 성능 평가)

  • Jung, Yong-Jo;Lim, Byung-Eul;Oh, Jang-keun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.5
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    • pp.59-67
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    • 2016
  • In landscape design by public institutions, although the costs and species of landscape trees stipulated by the Korean Public Procurement Service(PPS) are generally adhered to, the PPS regulations about planting trees with well-developed rootlets are almost entirely neglected. This study aimed to evaluate the performance of buried container modules, which are a new technology and product in landscape production that is able to reduce the defect rate while complying with regulations. To this end, this study measured rootlet density, rootlet development length, rootlet survival rate on excavation, and impairments of tree growth for 3 months after root pruning, and compared these variables for the container modules with those for trees that underwent root pruning in bare ground, and those that were cultivated in a container above ground. The results were as follows: First, the rootlet density was 88% for the trees in container modules, which was very high. Trees that underwent standard root pruning in bare ground had a somewhat lower density of 64%. Meanwhile, the trees that were cultivated in pots above ground died, invalidating measurement. Second, in terms of rootlet development and rootlet survival rate, the trees in container modules showed a mean length of 10.4cm, and 100% survival rate, indicating that there was no rootlet damage caused by excavation. For the trees that only underwent root pruning in bare ground, the mean length was 25.6cm and the rootlet survival rate was only half that of the trees in container modules, at 56%, demonstrating considerable damage. Rootlet development did not occur at all in the trees grown in pots. Third, the trees in container modules and those that underwent root pruning in bare ground did not show any deaths during the root pruning process, or any impairments such as stunted leaf growth. Conversely, the trees grown in pots nearly all died, and severe impairments of tree growth were observed. As shown by the results above, when we evaluated the performance of buried container modules, they showed the most outstanding performance of the three models tested in this study. The container modules prevent defects by stimulating early rooting in environments that with poor conditions for growth, or in trees that are not suited to the summer environment Therefore, it is expected that they would be an optimal means by which to enable compliance with rules such as the regulation presented by the PPS.

Dietitians' Customer Orientation at Contract Foodservice Management Company (위탁급식전문업체 영양사의 고객지향성 분석)

  • Shin, Seo-Young;Kim, Hee-Yeon;Choi, Mi-Kyung;Yang, Il-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.6
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    • pp.801-808
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    • 2006
  • The purposes of this study were to measure customer orientation of dietitians engaged in contract foodservice management companies, and to examine the impacts of personal characteristics and organizational characteristics on the customer orientation of dietitians. The questionnaires developed for this study were distributed to 230 dietitians of contract foodservice management companies, including 4 major companies, in Seoul and Gyeonggi areas. A total of 187 (81.3%) questionnaires were used for analysis, and statistical analyses were conducted using SPSS (Win 11.5) for descriptive analysis, correlation analysis, t-test and ANOVA. The average customer orientation score of the dietitians was 3.77 (SD=0.40) and it seemed that most respondents evaluated themselves as customer-oriented. Further analyses revealed significant differences in customer orientation among different position (p<0.05) and payroll (p<0.01) groups.'Type of menu' also affected the customer orientation (p<0.01). Overall, it is needed to design efficient training programs that improve service skills and customer orientation of dietitians, and the understandings on variables affecting customer orientation would help it.

Analysis of the Effect of Heat Island on the Administrative District Unit in Seoul Using LANDSAT Image (LANDSAT영상을 이용한 서울시 행정구역 단위의 열섬효과 분석)

  • Lee, Kyung Il;Ryu, Jieun;Jeon, Seong Woo;Jung, Hui Cheul;Kang, Jin Young
    • Korean Journal of Remote Sensing
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    • v.33 no.5_3
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    • pp.821-834
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    • 2017
  • The increase in the rate of industrialization due to urbanization has caused the Urban Heat Island phenomenon where the temperature of the city is higher than the surrounding area, and its intensity is increasing with climate change. Among the cities where heat island phenomenon occurs, Seoul city has different degree of urbanization, green area ratio, energy consumption, and population density in each administrative district, and as a result, the strength of heat island is also different. So It is necessary to analyze the difference of Urban Heat Island Intensity by administrative district and the cause. In this study, the UHI intensity of the administrative gu and the administrative dong were extracted from the Seoul metropolitan area and the differences among the administrative districts were examined. and linear regression analysis were conducted with The variables included in the three categories(weather condition, anthropogenic heat generation, and land use characteristics) to investigate the cause of the difference in heat UHI intensity in each administrative district. As a result of analysis, UHI Intensity was found to be different according to the characteristics of administrative gu, administrative dong, and surrounding environment. The difference in administrative dong was larger than gu unit, and the UHI Intensity of gu and the UHI Intensity distribution of dongs belonging to the gu were also different. Linear regression analysis showed that there was a difference in heat island development intensity according to the average wind speed, development degree, Soil Adjusted Vegetation Index (SAVI), Normalized Difference Built-up Index (NDBI) value. Among them, the SAVI and NDBI showed a difference in value up to the dong unit and The creation of a wind route environment for the mitigation of the heat island phenomenon is necessary for the administrative dong unit level. Therefore, it is considered that projects for mitigating heat island phenomenon such as land cover improvement plan, wind route improvement plan, and green wall surface plan for development area need to consider administrative dongs belonging to the gu rather than just considering the difference of administrative gu units. The results of this study are expected to provide the directions for urban thermal environment design and policy development in the future by deriving the necessity of analysis unit and the factors to be considered for the administrative city unit to mitigate the urban heat island phenomenon.

Optimization of Interesterification Reaction for the Continuous Production of trans-Free Fat in a Packed Bed Enzyme Bioreactor with Immobilized Lipase (고정화 리파제를 이용한 충진형 효소생물반응기 내에서의 무-트랜스 유지 연속 생산을 위한 에스테르 교환 반응의 최적화)

  • Kim, Sang-Woo;Park, Kyung-Min;Ha, Jae-Uk;Lee, Jae-Hwan;Chang, Pahn-Shick
    • Korean Journal of Food Science and Technology
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    • v.41 no.2
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    • pp.173-178
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    • 2009
  • Epidemiological studies showed that high trans-fat consumption is closely associated with getting the risks of cardiovascular disease. The objective of this study was to produce trans-free fat through lipase-catalyzed interesterification, as a substitute for the cream margarine commonly used in industry. Optimum conditions for interesterification in a packed bed enzyme bioreactor (PBEB) were determined using response surface methodology (RSM) based on central composite design. Three kinds of reaction variables were chosen, such as substrate flow rate (0.4-1.2 mL/min), reaction temperature (60-70$^{\circ}C$), and ratio of fully hydrogenated canola oil (FHCO, 35-45%) to evaluate their effects on the degree of interesterification. Optimum conditions from the standpoint of solid fat content (SFC) were found to be as follows: 0.4 mL/min flow rate, 64.7$^{\circ}C$ reaction temperate, and 42.8% (w/w) ratio of FHCO, respectively. The half-life of immobilized lipase in PBEB with two stages at 60$^{\circ}C$ ($1^{st}$ stage) and 55$^{\circ}C$ ($2^{nd}$ stage) was about more than 30 days as estimated by extrapolating the incubation time course of tristearoyl glycerol (TS) conversion, whereas the half-life of the enzyme in PBEB with single stage at 65$^{\circ}C$ was only about 15 days. Finally, the results from SFC analysis suggest that trans-free fat produced in this study seems to be a suitable substitute for the cream margarine commonly used in industry.

A Study on Balanced -type Oseillating Mole-Drainer(III)-Model Test for Draft Force, Torque, Power and Moment (평행식 진동탄환 암거 천공기의 연구(III)-견인력, 토크, 동력 및 모멘크에 관한 모형시험-)

  • 김용환
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.1-6
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    • 1976
  • This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

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