• Title/Summary/Keyword: national project

Search Result 5,332, Processing Time 0.034 seconds

A Study on the Methodology of Land-Consolidation Sloping Paddies in land Vallry for the Farm-Mechanization (II) (기계화를 전제로 한 산간경사지답경지정리방안에 관한 연구(II))

  • Hwang, Eun
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.24 no.4
    • /
    • pp.57-68
    • /
    • 1982
  • The paddy fiels slope located in Kangweon province Hwyongsung gun Gonggeun myon Shinchonri was considerably steep and so it was impossible to economically consolidate the field up to date. But for the porpose of farm mechanization, the field (32. 27ha) was consolidated by the auther under the assitance of the Ministry of Agriculture and Fishery and,;the Administration of Kangweon province. This paddy field consolidation was caused by the treatise on "Land-consolidation methods for farm mechanization in the steep-sloped paddy field", of which the auther is the same. The constrution was carried out from September, 1981 to April, 1982. During the 4esign and construction, some Peculiarities were found and discussed. That is, in design, besides the common condititions for a design, some special conditions were considered and written below; (1) The ranges of field slope in this design were 1/100-1/30. (2) Long sides of the land readjustment blocks must be arranged abreast contour line, and so they make the amount of cutting and banking decreased so as to take the maximum advantage of the configuration of the field. (3) In design, the main principles of dividing blocks were written below; i) First of all, long side of a block should be drawn straight abreast a contour line. ii) Long side of a block should arrange abreast contour line and make its length 100-150m, if not, l)reak the side in order to make a bended rectangle. iii) Length of a short side should be determinded within differences of elevation (0.6 -1. 2m) between the two adjacent blocks toward the normal to a contour line. iv) Length of a short side should be above 15m and the ratio of long and short side should be slso kept 1: (4-6). v) A new field surface leveling was determinded from the elevation which produce the least amount of cuttingand banking within the range of 0.6-1. 2m diffe rences of elevation between the two adjacent blocks. vi) In the course of dividing blocks with the same width along the line which was normal to a contour line, all blocks connot keep their shape in a retangle because of steep slope of the field and so on, and so it was also necessory to make some non-retanglar and small blocks such as a trianglar or trapezoidal shape, which was impossible to use some of farm machinery. But because this non-rectanglar and small blocks were divided, larger and many rectanglar blocks can be divided and construction cost can also be lowered. According to the conditions discussed above, the paddy field consolidation project designed and constructed. And the results of this study were obtained as below; (1) Three-forth of total cost of this paddy field consolidation was not construction cost, and these cost consist of land grading (1/4), road and canal construction cost (1/4) and the other cost (1/4) such as surveying or materials and 56 on. (2) The steeper the land slope, the greater cost was assigned for road and canal construction, and than land grading. (3) Curtailment of the road and canal construction cost depended on simplificating their strutures. (4) In the case of the land slopes were low, the land grading cost was high by 1: 1.4 in comparison with the road and canal construction cost, and conversely when the slops were steep, the road and canal construction cost was high by 1 : 5 in compa- rison with the land grading cost. (5) The densities of irrigation canal, drainage canal and trunk and branch road were 150. Sm/ha, 60. im/ha and 17. 4m/ha respectively. The density of irrigation canal of the area was high by 2 times in comparison with the average one of Kangweon Province, and the others were nearly the same. (6) Most farmers (above 85%) knew the effects of paddy field consolidation. The effects are; 1) Improvement of irrigation 2) Improvement of farm management 3) Improvement of transportarion 4) farm mechanization and 5) grouping of the scattered land. And the more farm modernization was accomplished by these projects, the more farmers wanted to live in their land. (7) In spite of the very steep sloped paddy field, the diminution rate of the net farm land caused by consolidation was 7.7% which was nearly the same as the one of Chulweon plain of Kangweon province. Land grading cost was 971, OOOwon/ha which was rather cheap by 13.2% than the one of Ghulweon plain, and unit construction cost was 5, 341, OOOwon/ha (included soil addition) which was also nearly the same as the one of Chulweon plain and FNFIA (The federation of national farmland improvement association).

  • PDF

Method for increasing rail operation capacity of capital high speed rail with expanding the high speed railway service (고속철도 서비스 확대를 위한 수도권 고속철도 확충 방안 고찰)

  • Roh, Beung-Guk;Kim, Young-Bea;Shin, Dong-Won
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.1254-1268
    • /
    • 2009
  • In 1998, because of the economic crisis called IMF Crisis in Korea, Kyungbu high speed railway project could run by modifying the original plan to open it as a 1st phase only by utilizing the existing railway lines from Seoul to Siheung and the other one from Daegu to Pusan. The modified plan includes that the line from Daegu to Pusan will be constructed as a second phase in next time. Starting railway operation with the changed plan, the combined application operation of high speed rail, passenger rail and freight rail was caused partly from Seoul to Siheung to run into capital area. As a result, the opinion for additional railway line construction is insisted continuously because the operation volume of passenger rail was forced to be reduced, the service quality of it was decreased and it became difficult to add new high speed services. Moreover, with regard to Honam high speed rail, the new construction plan of station in Kangnam metro area as a basement station for starting from Suseo was changed to the plan of turning out at Osong because of the economic effectiveness and this kept resident people in Kangnam metro area and southern Kyungki area unable to get the opportunity of high speed rail service benefit. After beginning of Kyungbu high speed railway operation, national transportation system developments are focused on high speed rail, and when the second phase construction of Kyungbu high speed rail, beginning operation of Kyungjeon line, Jeolla line double track construction, Honam high speed rail in 2014, is completed, the demand for high speed rail will be increased and it is unavoidable to make Kwangmyung station as a basement station and to reduce the number of passenger rail operation. At this moment, it is valuable to consider adding the railway line capacity in capital area to improve the transferring service for citizen who live in area without Kyungbu high speed rail station and to expand the service area from Kangbuk to Kangnam and southern Kyungki area. Accordingly, in this paper, the effective rail operation method, facility plan and the other issue to be reviewed for increasing capital high speed railway lines will be mentioned.

  • PDF

Basic Research on the Environment of Oral Health Promotion in the Parent Cooperating Daycare Facilities Based on the Survey for the Nursery Teacher (일부 부모협동보육시설 보육교사 대상의 시설내 구강건강증진 환경에 관한 조사)

  • Kim, Cheoul-Sin;Han, Sun-Young;Gim, Ah-Reum;Bae, Soo-Myong;Jung, Se-Hwan
    • Journal of dental hygiene science
    • /
    • v.8 no.4
    • /
    • pp.331-336
    • /
    • 2008
  • The purpose of this research was to collect basic data to develop a project of oral health that fits for particularity for parent cooperating daycare facilities for infants and children. For this purpose, we gave out the self administrated surveys to the teachers at parent cooperating daycare facilities, and analyzed surveys made by teachers. The results of this research could be summarized as follows ;1.The snacks and drinks provided by parent cooperating daycare center tend to provide more non-cariogenic snacks and drinks such as fruit, vegetables and fruit juice. 2. Activities related to dental health was done in parents corporative daycare center are: Children participate in the activities and training related to food (87.9%), catering staff receive education about nutrition (78.2%), avoiding sugary food at a birthday party (74.0%), annual dental health check-up by a dentist (33.5%). 3. 88.9% of teachers agreed parents' involvement of developing policies of oral health. 4. The percentages of guiding principles based on documentation in the topic of the oral heath were: Involving parents in the formation of the pre-school group's health policy (47.8%), advising the needs of a child for dental service to parents (44.9%), coping with a situation where a child injured his or her teeth (44.9%).

  • PDF

A Study on Comparative Analysis of Socio-economic Impact Assessment Methods on Climate Change and Necessity of Application for Water Management (기후변화 대응을 위한 발전소 온배수 활용 양식업 경제성 분석)

  • Lee, Sangsin;Kim, Shang Moon;Um, Gi Jeung
    • Journal of Korean Society of societal Security
    • /
    • v.4 no.2
    • /
    • pp.73-78
    • /
    • 2011
  • In order to resolve the problem of change in global climate which is worsening as days go by and to preemptively cope with strengthened restriction on carbon emission, the government enacted 'Framework Act on Low Carbon Green Growth' in 2010 and selected green technology and green industry as new national growth engines. For this reason, the necessity to use the un-utilized waste heat across the whole industrial system has become an issue, and studies on and applications of recycling in the agricultural and fishery fields such as cultivation of tropical crops and flatfishes by utilizing the waste heat and thermal effluent generated by large industrial complexes including power plants are being actively carried out. In this study, we looked into the domestic and overseas examples of having utilized waste heat abandoned in the form of power plant thermal effluent, and carried out economic efficiency evaluation of sturgeon aquaculture utilizing thermal effluent of Yeongwol LNG Combined Cycle Power Plant in Gangwon-do. In this analysis, we analyzed the economic efficiency of a model business plan divided into three steps, starting from a small scale in order to minimize the investment risk and financial burden, which is then gradually expanded. The business operation period was assumed to be 10 years (2012~2021), and the NVP (Net Present Value) and economic efficiency (B/C) for the operation period (10 years) were estimated for different loan size by dividing the size of external loan by stage into 80% and 40% based on the basic statistics secured through a site survey. Through the result of analysis, we can see that reducing the size of the external loan is an important factor in securing greater economic efficiency as, while the B/C is 1.79 in the case the external loan is 80% of the total investment, it is presumed to be improved to 1.81 when the loan is 40%. As the findings of this study showed that the economic efficiency of sturgeon aquaculture utilizing thermal effluent of power plant can be secured, it is presumed that regional development project items with high added value can be derived though this, and, in addition, this study will greatly contribute to reinforcement of the capability of local governments to cope with climate change.

  • PDF

Present and Future of the Journal of Distribution Science (유통과학연구의 현재와 미래)

  • Kim, Dong-Ho;Youn, Myoung-Kil
    • Journal of Distribution Science
    • /
    • v.10 no.5
    • /
    • pp.7-17
    • /
    • 2012
  • The recent announcement of the National Research Foundation of Korea (NRF) to cease journal accreditation operations as of the end of the year 2014 can easily influence the future of many research journals in Korea. Although this plan has not yet been formalized or structured, its facilitation would be the major turning point for the current Korean research and scholarly journals and publications. In addition, the NRF's plan to select and fund top 20 or more research journals over the five year period beginning 2015 suggests that the competition will most likely increase among Korean journals. Each journal would need to develop its unique strategy to improve and strengthen its competitiveness to become or maintain its position as a major research journal in Korea. The association of Korean Distribution of Science (KODISA) and its research journal, Journal of Distribution Science (JDS), has been continuously improving its reputation as a reputable journal in the distribution and related fields since its establishment in 1999. Due to demand, JDS has had to undergo several changes in its publication cycle first from semiannual publication to quarterly, then finally to monthly publications in 2012, and has become one of the major social science journals in Korea. Furthermore, with the redesigning of its webpage with English language in July of 2011, KODISA has made the published journals freely accessible and available to both domestic and foreign researchers, scholars, practitioners, and learners. These changes have resulted in the rapid increase in the bounce rate and the number of journal submissions by foreign scholars, with four research articles having been submitted by foreign scholars just in March of 2012 alone. However, although the changes and outcomes have resulted in a reasonable success so far, the achievement may only become a short-term success without continuously developing, improving, and implementing both effective and efficient strategies through critical, thorough, and frequent examinations and evaluations of both KODISA and JDS. As such, the purpose of this research is to carefully examine both KODISA and JDS to identify problematic factors and to develop appropriate strategies to change or modify those problems for further strengthening and improving their reputation and status. The paper examines and analyzes the past, present, and future of KODISA and JDS and their managerial, operational, and systematic procedures and operations. The narrow scope of research and inefficiencies in promoting the association and the journal and the improvement of impact factors are identified as the notable problems that could hinder JDS from being included in SCOPUS or SSCI in the near future. This type of examination and exploration has not been previously conducted, so the major limitation of this paper can be identified as not meticulously elaborating on the problems nor proving detailed recommendations based on the existing researches. This article asserted that solving the problem of the narrow scope of research would lead to facilitation of resolving other inefficient problems. Inclusion of international academic disciplines to the distribution and their related fields would be the viable initiation of expanding the research area, and this strategy could promote the journal as well as improve its impact factors. The narrow scope of research seems to be a good research topic and merit further exploration as an individual research project, because this kind of research could yield the creation of new understandings or theories.

  • PDF

The Comparative Evaluation of Plant Species Diversity in Forest Ecosystems of Namsan and Kwangneung (남산(南山) 및 광릉(光陵) 산림생태계(山林生態系)의 식물(植物) 종다양성(種多樣性)의 비교 (比較) 평가(評價))

  • Kim, Ji Hong;Lee, Byung Cheon;Lee, You Mi
    • Journal of Korean Society of Forest Science
    • /
    • v.85 no.4
    • /
    • pp.605-618
    • /
    • 1996
  • Namsan area supposed to be a disturbed ecosystem and Kwangneung area considered to be a natural ecosystem were selected for the study. On the basis of the plant species composition, the study was planned to examine structural plant species diversity so as to provide basic ecological information to restore more stable and healthy ecosystem for Namsan. The stratified sample plot method was employed for collecting vegetation data, establishing $20m{\times}20m$ square plots for overstory trees, $4m{\times}4m$ plots for mid-story woody plants, and $1m{\times}1m$ plots for ground vegetation. The herbaceous plants were periodically investigated by taking into account for seasonal(spring, summer, and autumn) variation in presence. Ecological attributes were evaluated through analyzing species composition, species diversity, life forms, interspecies association, and growing habitat for various forest types, vertical layers, life forms, and seasonal variation. Even though the species diversity index of canopy trees in the deciduous forest of Namsan was estimated higher than that of the natural forest of Kwangneung, overall species diversity of plants in Kwangneung area was greater than that in Namsan area. Herbaceous plants presented in Kwangneung but not in Namsan were Aconitum pseudo-proliferum, Botrychium virginianum, Dryopteris tokyoensis, Scutellaria insignis, Tricyrtis dilatata, and Viola kamibayashii, most of them were endemic species of Kwangneung. Elaeagnus umbellata, and Prunes padus var. seoulensis were found only in Namsan. Such species typically composed of the natural deciduous forest as Acer mono, Acer triflorum, Carpinus laxiflora, Cornus controversa, Fraxinus mandshurica, and Phellodendron amurertse were limited growing in a small size of area in Namsan. The future project should be made for encouraging the growth and expansion of the distribution of such species to restore biodiversity in Namsan area.

  • PDF

A Study on Childbrith in Late Maternal Age (노령출산에 관한 연구)

  • Han Yea Young
    • Journal of Korean Public Health Nursing
    • /
    • v.8 no.2
    • /
    • pp.101-113
    • /
    • 1994
  • Maternity means all the women who are capable to conceive. In the aspect of health and medical care. however. it means the women who are now in pregnancy or have already given birth to a baby or are in a period of being recoverd from physiological changes occurred by pregnancy. According to the rapidly changing social structure. both the Quality and Quantity of the capacity of childbirth experienced by women are changing. Our society. having established a great economical growth by virtue of the highly developing and growing industrialization and urbanization. stimulates the women's advance into society and thereby increasing the number of employed women. When the women's participation in society is increased. their age of marriage is also affected. Which means there are a decrease of the capacity of childbirth in terms of quantity and a trend for women to have less children and to deliver a baby in their old age in terms of quality. On the contrary. since the number of multipara who want to have a baby in their old age is increasing. as a counter functional effect to the political project of decrease of a birth rate. concern has been focussed on childbirth in old age in the present study. And also such kind of the childbirth may be danger to the health of both mother and baby. Therefore the present study intended to provide some basic data of health education in the part of the health management of both mother and baby in the general hospital. based on understanding the realities of childbirth in. old age and things related to them. To achieve such a purpose of the present study. an analytical study by means of SPSS. was done using the data of 269 clinical records on both the newborn .babies and their mothers who had been supported by public general hospitals located in Seoul for 3 years from Jan. 1. 1991 to Dec. 31. 1993. Some significant results from the analytic study are as follows: 1. It appeared that the average age of normal. natural delivery was 33.8 years old and the average age of delivery through the cesarean operation was 35.4 years old. 2. It appeared that danger factors to childbirth women were types of the delivery and placental extrusion and danger factors to newborn babies are not so outstanding. 3. It appeared that the variables of the childbirth capacity which showed a significant difference according to each age group of women were the number of pregnancy. number of still birth, and number of existing children. That is. the age group of 'more than 35 years' had more frequency of experience In all 3 variables than the age group of 'less than 35 years'. 4. It appeared that the variables of the childbrith capacity which showed a significant difference a according to the sex of a newborn baby were number of pregnancy, number of still birth, and number of existing children. That is, the age group of 'more than 35 years' had more frequency of experience in all 3 variables than the age group of 'less than 35 years'. 5. It appeared that the health index of newborn babies which showed a significant difference was only 5 minute APGAR. That is, the health index 9.46 in the age group of 'more than 35 years' was less than an index of 9.72 in the age group of 'less than 35 years'. 6. Since a counter correlation of -0.10, as Pearson Correlation Coefficient, was showed between the age of childbirth mothers and the weight of newborn babies, it indicated that the higher age of childbirth woman, the lesser the weight of newborn baby. 7. It appeared that the number of women who had confirmed the sex of their baby before their delivery were 45 women, $67.2\%$ of total 67 women who had delivered a baby. and the expected sex by women in childbed was male with $73.1\%$ of total childbirth women expecting male birth and with their expression of feeling of female delivery. very regretful' by $39.3\%$ of total childbirth women. The results as shown above may indicate that instead of the possibility of danger to both the mother delivering a baby in old age and the baby delivered, the expectation of getting a son motivates childbirth in old age. As a conclusion, in a dimension of general hospital as well as national reform. it is required that a program of health education for childbirth in late maternal age have to be developed in the part of the health management of both mother and baby in the near future.

  • PDF

Effect of NIE Program to Science-Related Attitude and Learning Achievement of Middle School Students (NIE 프로그램이 중학생들의 과학과 관련된 태도와 학업 성취도에 미치는 영향)

  • Kim, Sug-Young;Choi, Seong-Hee
    • Journal of the Korean earth science society
    • /
    • v.21 no.4
    • /
    • pp.359-368
    • /
    • 2000
  • The purpose of this study is to develope and apply NIE programs related to sub-chapter 'The Change of Weather and Circulation of Water' in 2nd grade science text book of middle school, and thereby to investigate the effects of NIE approach on science-related attitude and teaming achievement of students, and interaction between treatment methods and students' learning ability. Subjects consisted of 2nd grade students of four classes in a girls middle school located at the southern part of Seoul. Four classes were divided into experimental and control groups by two classes randomly. The experimental groups have been instructed on the related-general concepts for six times and then received seven NIE programs developed by researcher for seven times. The control groups have received the instruction through the conventional teaching method. The NIE learning has been progressed following the steps using in the Iowa Chautaugua Program, e.g. invite, explore, propose explanation and solutions, and take action. NIE programs, e.g. project studying, topic studying and a crossword puzzle have been developed and applied using 'science first' approach of the STS instruction. Twenty questions related to social implications of science and leisure interest in science within seven frameworks of TOSRA have been used in this study as an evaluation instrument of science-related attitude. Learning achievement has been evaluated using an instrument developed by researcher. The results of this study can be summarized as follows. (1) NIE approach was more effective in progressing learning achievement of middle school students than conventional teaching method (p<.01). (2) Experimental groups show statistically significant improvement on science-related attitude than control groups (p<.01). There were no significant interactions between treatment methods and students' learning ability on learning achievement and leisure interest in science. The NIE approach were more effective than the conventional one on social implications of science, especially to low ability students.

  • PDF

Appling Nursing Theory to Clinical Practice of Home Health Care (가정간호실무에 적용가능한 이론적틀)

  • Woo, Seon-Hye
    • Journal of Home Health Care Nursing
    • /
    • v.11 no.1
    • /
    • pp.5-13
    • /
    • 2004
  • The home health care industry has grown rapidly and can be expected to continue to grow in the foreseeable future. Home health care refers to the practice of nursing applied to clients with a health condition in the clients place of residence. clients and their designated care givers are the focus at home health nursing practice. The goal of care is to initiate. manage and evaluate the resources needed to promote the clients optimal level of well-being and function. Nursing activities necessary to achieve this goal may warrant preventive maintenance and restorative emphases to prevent potential problems from developing. Many project program were suggested home health care model for Korea's health care system and policy direction for expansion and establishment of home health care .But the aim of this paper is to provide on overview for theoretical frame work in home health care. Theories and conceptual frameworks or models are important nursing because they define and guide the boundaries of professional practice and identify key nurse-patient-caregiver relationships that emerge with caring. Following is the research with an investigation of the literature review in the University of Arizona international medline database, In conclusion, are as followers: First, many nursing theorists have had a tremendous impact on nursing practice. the following highlights those nursing theorists that are particularly helpful in understanding home health care. 1. Florence Nightingale : Our earliest theoretical legacy. Nightingale's believes are reflected in basic infection control practice such as hand washing and infectious waste disposal and are key nursing interventions in home care. 2. Martha Roger's :Science of unitary human beings theory. Rorger's believed that the focus of shared. non invasive healing modelities is the human environmental field rather than direct physical care. These modelities continue to evolve as our awareness (reflecting greater diversity, faster rhythms, motions, and ways of knowing) transcends time and space, allowing individuals to get in touch with their integral nature of unbroken wholeness. On people as ever changing energy fields have special relevance in home care especially with hospice and palliative care applications. 3. Madeline Leininger's; Transcultural nursing theory. Home care nurses move through a variety of communities and often care for patients from different cultural back grounds. Therefore Leininger's work has a good that with home care because home care nursing practice is very culturally focused. 4. Dorothea Orem's : Self care deficit theory. Orem's theory views care as something to be performed by both nurses and patients. The role of the nurse is to provide education and support that help patients acquire the necessary activities to perform self-care. Orem's theory is foundational to have care because it begins to truly acknowledge the role of the patient in managing his or her own health. which is referred to as self-care. 5. Margaret Neuman's; Health as expending consciousness theory. Neuman believes that health compasses disease and reflects an underlying pattern of person-environment interaction. A key application of 'Neuman's work to home care is for nurses to understand that health and illness do not necessarily exist at opposite ends of a continuum. 6. Jean Watson's: Theory of human caring. Watson's theory of human caring in nursing proposes human caring as the moral ideal of nursing. Nurses participate human caring to protect, enhance and preserve humanity by assisting individuals to fing meaning in illness. pain and existence and to help others gain self knowledge. self control. and self healing such thinking lends richness to theory development. as well as clinical practice in home care. Second, Robin Rice : Dynamic self determination for self care. (A theoretical framework for home care) Dynamical self determination for self care can be useful to home care nurses in a variety of ways. As research tool it can be reflected in the interview process when the home visit. The home care nurse's role is that of facilitator of patient self-determination for self care through numerous strategies. including patient education and case management.

  • PDF

A Comparative Study of Korean Home Economic Curriculum and American Practical Problem Focused Family & Consumer Sciences Curricula (우리나라 가정과 교육과정과 미국의 실천적 문제 중심 교육과정과의 비교고찰)

  • Kim, Hyun-Sook;Yoo, Tae-Myung
    • Journal of Korean Home Economics Education Association
    • /
    • v.19 no.4
    • /
    • pp.91-117
    • /
    • 2007
  • This study was to compare the contents and practical problems addressed, the process of teaching-learning method, and evaluation method of Korean Home Economics curriculum and of the Oregon and Ohio's Practical Problem Focused Family & Consumer Sciences Curricula. The results are as follows. First, contents of Korean curriculum are organized by major sub-concepts of Home Economics academic discipline whereas curricular of both Oregon and Ohio states are organized by practical problems. Oregon uses the practical problems which integrate multi-subjects and Ohio uses ones which are good for the contents of the module by integrating concerns or interests which are lower or detailed level (related interests). Since it differentiates interest and module and used them based on the basic concept of Family and Consumer Science, Ohio's approach could be easier for Korean teachers and students to adopt. Second, the teaching-learning process in Korean home economics classroom is mostly teacher-centered which hinders students to develop higher order thinking skills. It is recommended to use student-centered learning activities. State of Oregon and Ohio's teaching-learning process brings up the ability of problem-solving by letting students clearly analyze practical problems proposed, solve problems by themselves through group discussions and various activities, and apply what they learn to other problems. Third, Korean evaluation system is heavily rely on summative evaluation such as written tests. It is highly recommended to facilitate various performance assessment tools. Since state of Oregon and Ohio both use practical problems, they evaluate students mainly based on their activity rather than written tests. The tools for evaluation include project documents, reports of learning activity, self-evaluation, evaluation of discussion activity, peer evaluation in a group for each students for their performance, assessment about module, and written tests as well.

  • PDF