• Research in Community and Public Health Nursing
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• v.14 no.2
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• pp.190-199
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• 2003

This study was conducted to determine the factors affecting job satisfaction in workers by using the Job Stress Model proposed by the National Institute for Occupational Safety and Health (NIOSH). Data were collected from December 1 to December 30, 1999. The subjects were 2,133 workers employed at 155 work sites, who were examined using NIOSH Job Stress questionnaire translated by the Korea Occupational Safety ${\pounds}|$ Health Academy and Occupational Safety ${\pounds}|$ Health Research Institute. SAS/PC program was used for statistical analysis using descriptive analysis. Pearson's correlation coefficient, ANOVA, and Stepwise multiple regression analysis. The results of this study were as follows. 1. According to general characteristics of the subjects, job satisfaction was high in those with less number of children. 2. By work condition, job satisfaction was higher in those who were working in a permanent job position, were working with regular time basis than with shift basis, were working in regular shift hours than in changing shift hours, were working for a short period, and were working less hours and overtime works per week. 3. In terms of physical work environment, job satisfaction was significantly related to 10 physical environmental factors. In other words, job satisfaction was high in workers who were working in an environment with no noise, bright light, temperature adjusted to an appropriate level during summer and winter, humidity adjusted to an appropriate level. well ventilation, clean air, no exposure to hazardous substance during work hour, overall pleasant work environment and not crowded work space. 4. By work-related factors, job satisfaction was high in those with less ambiguity about future job and role, high job control/autonomy, and less workload. On the other hand, job satisfaction was low in those with little utilization of competencies, and much role conflict at work and workload. 5. As for the relationships between job satisfaction and the non-work related factors, job satisfaction was high in workers who were volunteering at different organizations or active in religious activities for 5-10 hours per week. 6. In the relationships between job satisfaction and buffering factors, significantly positive correlations were found between job satisfaction and factors such as support by direct superior, support by peers, and support by spouse, friend and family. 7. There were nine factors that affected job satisfaction in the workers: age, number of children, work hours per week, noise, temperature at the work site during summer, uncomfortable physical environment, role ambiguity, role conflict, ambiguity in job future, work load, no utilization of competencies and social support from direct supervisor. These nine factors accounted for 26% of the total variance in the multiple regression analysis. In conclusion. the following are proposed based on the results of this study. 1. The most important physical environmental factors affecting job satisfaction in workers were noise, role ambiguity, and work load, suggesting a need to develop strategies or programs to manage these factors at work sites. 2. A support system that could promote job satisfaction is needed by emphasizing the roles of occupational health nurses who may be stationed at work sites and manage the factors that could generate job stress. 3. Job satisfaction is one of the three acute responses to stress proposed in NIOSH job stress model (job satisfaction. physical discomfort and industrial accidents). Therefore, further studies need to be conducted on the other two issues.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.223-230
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• 1994

A practical study on a drying and fermentation system equipped with a stirring machine operated mechanically, of pig manure was conducted to prove the efficiency of and practicability to an ordinary pig farm. The type of the drying bed was a round-shaped (r=3m) concrete structure and the stirring machine was adopted to stir and transfer dried pig manure to the fermentation tank. The dried pig manure was put into a fermentation tank ($V=18m^3$), which was aerated from pipe lines installed at the bottom. While water content of pig manure passing through a drying bed was remarkably reduced than before drying, the drying efficiency of this system decreased in winter. However, the temperature of pig manure piled up in the fermentation room in winter reached over $60^{\circ}C$ and excess water of pig manure was removed during the fermentation process. The reduction rate of water content of pig manure, to which dried pig manure was added as bulking material on the drying bed, was 52.1%, but when dried without bulking material it was only 19.7%. Although the content of $P_2O_5$ of dried pig manure was slightly higher than that of fresh pig manure, progressive changes in chemical composition between fresh and dried pig manure made no great difference. Among the contents of minerals of fresh and dried pig manure, CaO was the highest and the rest were in the decreasing order of $K_2O$, MgO, and $Na_2O$. Population density of E. coli and Streptococci of dried pig manure was reduced by 142 and 236 times that of fresh pig manure, respectively. The installation cost of this drying and fermentation system was 4,185,630 won (approximately 5,232 US $) and operating cost per year was 190,000 won (237.5US $) on the basis of self-labor condition.

• Korea journal of population studies
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• v.19 no.1
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• pp.139-159
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• 1996

This study comparatively examines a causal model of employee attatchment which focuses on employee's organizational commitment and intent to stay with an organization. This study is based on two separate studies of employee attachment among teachers : the U.S. case of the Chicago Public Schools (CPS) and the South Korean case of the Seoul Educational District (SED). The main purpose of this study is to replicate in Korea the CPS study. A revised model based on the unique characteristics of Korean teachers is also developed and estimated. The Price Mueller model of employee attachment provides the basic theoretical framework for this study. It includes five general classes of variables : 1) employee responses to work variables : job satisfaction, commitment, and intent to stay; 2) psychological stress variables: role ambiguity, role conflict, work overload, and quality of students; 3) social structural variables: autonomy, routinization, distributive justice, and legitimacy; 4) economic structural variables: pay, job security, promotional opportunities, and job opportunities; and 5) work orientation variables : career commitment, normative commitment, work motivation, affectivity, work values, and met expectations. The data was collected through questionnaire survey and a sample of 649 secondary school teachers in Seoul, South Korea, was included in the final analysis. Covariance structure analysis (LISREL) was used to estimate the causal model. The results indicate that the endogenous variables of job satisfaction and commitment play a considerably less important role than in the U.S. model in mediating the effects of the exogenous variables on intent to stay, and the model fails to explain the majority of the variance in intent to stay. In addition, the new variables added to the revised Korean model do not bave significant effects on intent to stay. The structural characteristics of the employment relationship and labor markets associated with Korean teachers forced mobility and closed external markets - are largely accountable for the major differences between the Korean and the U.S. cases. The study suggests that conceptual and empirical work on what produces employee attachment under these structural constraints needs to receive more attention in future studies.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.164-179
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• 1991

Korean agriculture has encountered two problems. One is internal income disparity between rural and urbarn area and the other is external Uruguay Round trade problems as an abolition of direct and indirect import barriers, reduction in export subsidies and to reduce internal price supports. These problems will be brought severe farm problems such as decreasing farm household income and repressing agricultural growth in the near future. Considering the above inevitable facts Korean government has implemented several development projects such as rural industrial area development project, rural special production area development project, leisuresight seeing farm development project, traditional food development project, unskilled labor training project for off-farm employment and so on, to increase farm household income through off-farm income increase. This study was mainly concentrated on the identification of operational problems and post evaluation of the rural special production area development projects which aimed at increasing non-farm incomes and giving employment opportunity for rural farmers in small factories processing regional special farm products and mine products. The main findings and problems to be solved for the successful project implementation are as followed ; 1. Total number of the special production area development projects as of the end of 1991 was amount to 138, and total number of farm household participated were estimated at 2,079, and total amount of off-farm income per farm household was reached to 3,011 thousand won. 2. The total number of processed special products have increased from 21 items in 1981 to 56 items in 1991. On the other hand the total number of farm household participated in the projects have decreased from 2,518 to 2,079 during same period. 3. Total amount of investment for the projects has increased from 1,429 million won in 1981 to 24,760 million won in 1991 but the rate of G'T loan of the total investment has reduced from 24.5% to 5.2% during same period. 4. 138 special production area development project are classified into 6 kinds of commodity groups such as 19 of general industrial good production areas, 52 of folks-industrial art objects production areas, 39 of food processing areas, 9 of fiber and texstile processing areas, 18 of agricultural and fishery inputs processing areas and 1 of stone processing area. 5. The total production value in 1990 was estimated 20,169 million won of which export was amount to 2,627 million won. 6. The finacial rate of return of the UNGOK KUGIJA Tea processing Project operated by UNGOK coops and BAKSAN ginseng tea processing project were estimated at 45.4% (B/C Ratio=1.17, NPV=152.5 million won) and 17.7% (B/C Ratio=1.12, NPV=120.2 million won) respectively. 7. More favorite terms and condition of the loan including collateral problems have to be given to farmers participated. Heavy investment and G'T subsidy policies should be started for the successful project implementation anf farm household income increase. 8. To expand market demand of the rural special goods G'T have to provide special program of TV or other mass media for commodity propaganda and the total cost concerned must be supported by G'T subsidy. 9. The special farm products as GUGUJA,MOSI'Ramie', Ginseng. SOGOKJU,HEMP,Mushroom.DUGYUNJU and Chesnut processing projects have to be propelled and expanded for off-farm income increase in Chung Nam Province. 10. Direct operational pattern of the special production area by coops is more favorable to farmers and recommendable considering with off-farm income increase and market demand creation throughout Korea. 11. In rural area, special organizations for project appraisal are not exist. Accordingly special training program, project appraisal, formulation and preparation for civil servants concerned have to be prepared for project selection and sound implementation under limited budget and financial support.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.171-209
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• 2008

The Great Depression is one of the most important economic incidents in the twentieth century. A significant and long-lasting impact of this event is the rise of the government intervention to the economy. Under the catastrophic downturn of the economic condition worldwide, people required their government to play an active role for economic recovery, and this $mentalit{\acute{e}}$ prolonged even after the Second World War. Social science textbooks taught at Korean high schools mostly referred to the Great Depression for explaining the reason of government intervention in economy. However, the mainstream view commonly found in the textbooks provides a misleading theological interpretation. It argues that inherent flaws of the market economy causes over-production/under-consumption, and that this mismatch ends up with economic crisis. The chaotic situation was resolved by substitution of the governments for the market, and the New Deal was introduced as the monumental example ('laissez-faire economy ${\rightarrow}$over-production${\rightarrow}$the Great Depression${\rightarrow}$government intervention${\rightarrow}$economic recovery'). Based on economic historians' researches for past three decades, I argue that this mainstream view commits the fallacy of ex-post justification. Unlike what the mainstream view claims, the Great Depression was neither the result of the 'market failure', nor the recovery from the Great Depression but was due to successful government policies. For substantiating this claim, I suggest three points. First, blaming the weakness or instability of the market economy as the cause of the Great Depression is groundless. Unlike what the textbooks describe, the rise of the U.S. stock price during the 1920s cannot be said as a bubble, and there was no sign of under-consumption during the 1920s. On the contrary, a new consensus emerging from the 1980s among economic historians illustrates that the Great Depression was originated from 'the government failure' rather than from the 'market failure'. Policymakers of European countries tried to return to the gold standard regime before the First World War, but discrepancies between this policy and the reality made the world economy vulnerable. Second, the mainstream view identifies the New Deal as Keynesian interventionism and glorifies it for saving the U.S. economy from the crisis. However, this argument is not true. The New Deal was not Keynesian at all. What the U.S. government actually tried was not macroeconomic stabilization but price and quantity control. In addition, New Deal did not brought about economic recovery that people generally believe. Even after the New Deal, industrial production or employment level remained quite low until the late 1930s. Lastly, studies on individual New Deal policies show that they did not work as they were intended. For example, the National Industrial Recovery Act increased unemployment, and the Agricultural Adjustment Act expelled tenants from their land. Third, the mainstream view characterizes the economic order before the Great Depression as laissez-faire, and it tends to attribute all the vice during the Industrial Revolution era to the uncontrolled market economy. However, historical studies show that various economic and social problems of the Industrial Revolution period such as inequality problems, child labor, or environmental problems cannot be simply ascribed to the problems of the market economy. In conclusion, the remedy for all these problems in high school textbooks is not to use the Great Depression as an example showing the weakness of the market economy. The Great Depression should be introduced simply as a historical momentum that had initiated the growth of government intervention. This reform of high school textbooks is imperative for enhancing the right understanding of economy and history.

• Journal of Preventive Medicine and Public Health
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• v.18 no.1
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• pp.73-82
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• 1985

This study was conducted to evaluate nutritional status with the analysis of the factors which might influence on the prevalent condition of nutrients-intake. 373 persons who are above 60 years old in Chung-Gu, Seoul were surveyed from March 15 to March 30 in 1985. Results were as follows ; 1. General Characteristics 1) Male respondents among the entire respondents comprised 54.3% and female respondents comprised 45.7%. As for age, male and female respondents comprised 55.0% and 37.2% respectively. 2) As for the educational level of the respondents, illiteracy was 49.9% which was the highest. and those who graduated elementary school was 28.1% which was the second highest. And as for the comparison of the education of the male and female respondents, the educational level of male respondents was much higher than that of female respondents. 3) As for the final occupation of the respondents, those who were engaged in commerce comprised 30.8% which was the highest rate, and who were engaged in agriculture comprised 20.1% which was the second highest rate. And those who were engaged in labor comprised 12.3%. 2. The State of Nutrients-intake The energy of the male respondents was 61.4% of RDA and the protein was nothing but 66.8% of RDA. Except vitamin A, vitamin $B_1$ and niacin, calcium, iron, vitamin $B_2$, vitamin C were lower than RDA (the range: $67.5%{\sim}97.3%$). The energy of the female respondents was 70.0% of RDA and the protein was 58.8% which were lower than RDA. Except vitamin A and vitamin $B_1$, calcium, iron, vitamin $B_2$ vitamin C, niacin were lower than RDA (the range: $68.2%{\sim}98.9%$). 3. The various factors related to nutrients-intake 1) The composition of family and the food environment those who were living with their spouses comprised 44.8% which was the highest rate, and those who were living with their son's family comprised 33.5% which was the second highest rate and those who were living with their doughter's family comprised only 4.6%. Those who were living alone comprised 16.4%. The correlation with nutrient intake didn't show a clear relation. 2) Socio-economic state Those who said that they lacked in living expense comprised 32.7% and those who said that they lacked in pocket-money comprised 23.9%, The female respondents outnumbered the male respondents in lacking living expense or pocket-money. In the correlation with socio-economic, there was no striking relation with education level. However, it was shown that little relation in energy, fat in male and also fat and iron in female. The living expense and the satisfaction in pocket-money had also little relation with energy fat and vitamin C in male. 3) Nutrition knowledge and food habit (a) The state of nutrition knowledge and food habit In nutrition knowledge, those who scored less than 60 points were 32.9%, and those who scored more than 90 points were 21.0%. In food habit, those who scored less than 60 points were 26.5% and those who scored more than 80 points were 45%. (b) The corelation with nutrition knowledge and food habit In case of female respondents, nutrition knowledge had a little relation with the intake of cabohydrate, iron, and vitamin C. And we couldn't see a distinct phenomenon in food habit.

• Korean Security Journal
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• no.31
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• pp.157-185
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• 2012

Today, the emergence of cyberspace and advancement of globalization caused not only the transformation of our productive and conventional life but also the revolutionary transition of use of destructive violence such as crime and warfare. This transition of environmental condition connects various security threats which separatedly existed in individual, local, national, and global levels in the past, and transformed the mechanical sum of all levels of security threats into the organic sum of multi-dimensional security threats. This article proposes that the sum of multi-dimensional security threats is caused by the interconnectivity of various different levels of security threats and the integrated interdisciplinary perspective is essential to properly understand the fundamental existence of today's security problem and the reality of fear that we face today. The holistic security, the concept proposed here, is to suggest the mode of networked response to multi-dimensional security threats. The holistic security is suggested to overcome the conventional divisional approach based on the principle of "division of labor" and bureaucratic principles, which means more concretely that national security and criminal justice are divided and intelligence, military, police, prosecution, fire-fighting, private security, and etc. are strictly separated into its own expertise and turf. Also, this article introduces integrated security approaches tried by international organization and major countries overseas with the respect of the holistic security. The author have spent some substantial experience of participant observation, meetings, seminar, conference, and expert interviews regarding the issues discussed in the article in various countries including the United States, Russia, Austria, Germany, Canada, Mexico, Israel, and Uzbekistan for the last ten years. Intelligence and information on various levels of security threats and security approaches introduced in this paper is obtained from such opportunities.

• Journal of Korean Library and Information Science Society
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• v.11
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• pp.69-99
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• 1984

A dramatic development in the new technology of copying materials has presented us with massive problems on reconciling the conflicts between copyright owners and potential users of copyrighted materials. The adaptation to this changing condition led some countries to revise their copyright laws such as in the U. S. in 1976 and in Korea in 1984 for merging with the international or universal copyright conventions in the future. Copyright defined as exclusive rights given to copyright owners aims to secure a fair return for an author's creative labor and to stimulate artistic creativity for the general public good. The exclusive rights on copyrightable matters, generally for reproduction, preparation of derivative works, public distribution, public performance, and public display, are limited by fair use for scholarship and criticism and by library reproduction for its preservation and interlibrary loan. These limitations on the exclusive rights are concerned with all aspects of library services and cause a great burden on librarian's daily duty to provide balance between the rights of creators and the needs of library patrons. The fair use as one of the limitations on it has been coupled with enormous growth of a new technology and extended from xerography to online database systems. The implementation of the fair use and library reprography in Korean law to the local practices is examined on the basis of the new American copyright act of 1976. Under the draft revision of Korean law, librarians will face many potential problems as summarized below. 1. Because the new provision of 'life time plus 50 years' will tie up substantial bodies of material longer than the old law, until that date librarians would need permissions from the owners and should pay attention to the author's death date. 2. Because the copyright can be sold, distributed, given to the heirs, donated, as a whole or a part, librarians should chase down the heirs and other second owners. In case of a derivative work, this is a real problem. 3. Since a work has its protection from the moment of its creation, the coverage of copyrightable matter would be extended to the published or the unpublished works and librarian's work load would be heavier. Without copyright registration, no one can be certain that a work is in the public domain. Therefore, librarians will need to check with an authority. 4. For implementation of limitations on exclusive rights, fair use and library reproduction for interlibrary loan, there can be no substantial aggregate use and there can be no systematic distribution of multicopies. Therefore, librarians should not substitute reproductions for subscriptions or purchases. 5. For the interlibrary loan by photocopying, librarians should understand the procedure of royalty payment. 6. Compulsory licenses should be understood by librarians. 7. Because the draft revision of Korean law is a reciprocal treaty, librarians should take care of other countries' copyright law to protect foreign authors from Korean law. In order to solve the above problems, some suggestions are presented below. 1. That copyright clearinghouse or central agency as a centralized royalty payment mechanism be established. 2. That the Korean Library Association establish a committee on copyright. 3. That the Korean Library Association propose guidelines for each occasion, e.g. for interlibrary loan, books and periodicals and music, etc. 4. That the Korean government establish a copyright office or an official organization for copyright control other than the copyright committee already organized by the government. 5. That the Korean Library Association establish educational programs on copyright for librarians through seminars or articles written in its magazines. 6. That individual libraries provide librarian's copyright kits. 7. That school libraries distribute subject bibliographies on copyright law to teachers. However, librarians should keep in mind that limitations on exclusive rights are not for an exemption from library reprography but as a convenient access to library resources.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.114-119
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• 2012

We have conducted 4 experiments to develop the most environmental and effective use of the two-fluid fog system to prevent and exterminate whiteflies in tomato cultivation. In particular, these experiments used Vitamini tomatoes grown in stand-alone greenhouses at Buyeo Tomato Experiment Station as subjects. Each experiment utilized the fog system in a different way. The first experiment provided the control group, which was subject to the two-fluid fog system without additional humidity control. In the second experiment, the two-fluid fog system controlled the humidity level to be above 70%. The third and the fourth experiment utilized natural substances, which were 1.5 mg/L of Neem Oil and 2 mg/L of Oleic acid respectively, without additional humidity control. From the first experiment, we could observe that a simple use of the two-fluid fog system decreased the density of whiteflies in the greenhouses. This impact of the fog system on whiteflies was greater in the second experiment. By comparing the first and the second experiment, we concluded that whiteflies are more effectively prevented by maintaining a higher humidity level via the fog system's smaller water droplets that float in the air for longer time than the standard fog system in rather dry condition. In the third and the fourth experiments, the extermination level was 78% and 76.4% respectively, comparing only 53% in the first experiment without the humidity control. Therefore, using the natural substances in addition to the humidity control increases the extermination effectiveness. Considering the similar results from the 3rd and the 4th experiments, Oleic acid has a greater appeal for its lower price. Using the two-fluid fog system to both control the humidity on a daily basis and spray the substances for occasional extermination would reduce labor cost and increase production in an environmental way.

• Journal of Biosystems Engineering
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• v.4 no.1
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• pp.1-23
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• 1979

The use of barley seeder attached to rotary tiller in the rural area has a significant meaning not only for the solution of labor peak season, but also for the increase of land utilization efficiency. The facts that presently being used barley seeders are all based on the mechanical principles of the reverse rotation, center drive and are all using forward rotating tine, which is used to be easily and heavily worn out when it rotates reversely, raise problem of recommending them to rural area in Korea. Therefore, the main objective of the study was to develop new type of rotary tine attachable to barley seeders. To attain the objective the following approaches were applied. (1) The kinematic analysis of reverse rotating barley seeders. (2) The studies on the soil bin and artificial soil. (3) The comparative experiment on the power requirement of prototype tine. The results obtained from the studies are summarized as follow: 1. The kinematic analysis of barley seeder attached to rotary tiller: The following results were obtained from the kinematic analysis for deriving general formulae of the motion and velocity characterizing the rotary tine of barley seeders presently being used by farmers. a) The position vector (P) of edge point (P) in the rotary tine of reverse rotating, center drive was obtained by the following formula. $$P=(vt+Rcos wt)i+Rsin wt j+ \{ Rcos \theta r sin \alpha cos (wt- \beta +\theta r) +Rsin \theta r sin \alpha sin (wt-\beta + \theta r) \} lk $$ b) The velocity of edge point $(P^')$ of reverse rotating, center drive rotary tine was obtained by the following formula. $$(P^')=(V-wR sin wt)i+(w\cdot Rcoswt)j + \{ -w\cdot Rcos \theta r\cdot sin \alpha \cdot sin (wt-\beta +\theta r) + w\cdot Rsin \theta r\cdot sin \alpha \cdot cos (wt- \beta + \theta r \} k $$ c) In order to reduce the power requirement of rotary tine, the angle between holder and edge point was desired to be reduced. d) In order to reduce the power requirement, the edge point of rotary tine should be moved from the angle at the begining of cutting to center line of machine, and the additional cutting width should be also reduced. 2. The studies on the soil bin and artificial soil: In order to measure the power requirement of various cutting tines under the same physical condition of soil, the indoor experiments Viere conducted by filling soil bin with artificially made soil similar to the common paddy soil and the results were as follows: a) When the rolling frequencies$(x)$ of the artificial soil were increased, the densIty$(Y)$ was also increased as follows: $$y=1.073200 +0.070780x - 0.002263x^2 (g/cm^3)$$ b) The absolute hardness $(Y)$ of soil had following relationship with the rolling frequencies$(x)$ and were increased as the rolling frequencies were increased. $$Y=37.74 - \frac {0.64 + 0.17x-0. 0054x^2} {(3.36-0.17x + 0.0054x^2)^3} (kg/cm^3)$$ c) The density of soil had significant effect on the cohesion and angle of internal friction of soil. For instance, the soil with density of 1.6 to 1.75 had equivalent density of sandy loam soil with 29.5% of natural soil moisture content. d) The coefficient of kinetiic friction of iron plate on artificial soil was 0.31 to 0.41 and was comparable with that of the natural soil. e) When the pulling speed of soil bin was the 2nd forward speed of power tiller, the rpm of driving shaft of rotary was similar to that of power tiller, soil bin apparatus is indicating the good indoor tester. 3. The comparative experiment on the power requirement of prototype tine of reverse rotating rotary: According to the preliminary test of rotary tine developed with various degrees of angle between holder and edge pcint due to the kinematic analysis, comparative test between prototype rotary tine with $30 ^\circ $ and $10 ^\circ$ of it and presently being used rotary tine was carried out 2nd the results were as follows: a) The total cutting torque was low when the angle between holder and edge point was reduced. b) $\theta r$ (angle between holder and edge point) of rotary tine seemed to be one: of the factors maximizing the increase of torque. c) As the angle between holder and edge point ($\theta r$) of rotary tine was $30 ^\circ $ rather than $45 ^\circ $, the angle of rotation during cutting soil was reduced and the total cutting torque was accordingly reduced about 10%, and the reduction efficiency of total cutting torque was low when the angle between holder and edge point ($\theta r$) of rotary tine was $10 ^\circ $, which indicates that the proper angle between holder and edge point of rotary tine should be larger than $10 ^\circ $ and smaller than $30 ^\circ $ . From above results, it could be concluded that the use of the prototype rotary tine which reduced the angle between holder and edge point to $30 ^\circ $, insted of $45 ^\circ $, is disirable not only decreasing the power requirements, but also increasing the durabie hour of it. Also forward researches are needed, WIlich determine the optimum tilted angle of rotary brocket, and rearrangement of the rotary tine on the rotary boss.