• The Korean Journal of Emergency Medical Services
• /
• v.8 no.1
• /
• pp.87-104
• /
• 2004

This study selected the fifth and sixth graders of elementary school in Jeollanamdo who can express their opinions of safety consciousness and understand the items of questionnaire as the population. It selected 10 elementary schools under the supervision of Jeonnam Board of Education and sampled 700 students randomly from 2-3 classes in the 5th and the 6th grade. One preliminary survey was conducted to revise and complement the contents and forms of questionnaire with 70 students of a school from Apr. 1 to 6, 2004 and this study was conducted from Apr. 10 to 30, 2004. Data of this study were collected by explaining the purport of study to subjects after obtaining approval of principal and teacher of the school and distributing questionnaires. Total 700 questionnaires were distributed and 681 were collected (97%) and 602 were used for final analysis except 79 lacking responses. The results of this study are as follows. According to demographical characteristics of subjects, 'male' students were 302(50.%) and 'female' students were 300(49.8%) by sex and 'the 5th graders' were 285(47.3%) and 'the 6th graders' were 317(52.7%) in grade distribution. Residents at 'apartment house' were 406(67.4%) in residence type, 'going to school by foot' was 477 students(79.2%), 'high school graduates' were 297(49.3%) in fathers' education, 'high school graduates' were 366 (60.8%) in mothers' education, 'professional and office workers' were 231(38.4%) in fathers' job, 'full-time workers' were 283(47.0%) in mothers' job, and the number of siblings was one except myself in 343 students(57.0%). Respondents on the level of class showing 'good' were 340(56.5%) and those on the degree of adaptation to school life showing 'active' were 349(58.0%). On the characteristics related to safety education, 360(59.8%) responded it was 'very necessary', on the frequency of safety education at school for last one year, 339(56.3%) responded they had 'once or twice', on the frequency of safety education by parents, 279(46.3%) responded they 'often' had it, on the level of safety practice by parents, 347(57.6%) responded they practiced it 'frequently', on the source of knowledge of safety, 223(37.0%) responded they got it from 'parents, siblings and relatives', on the degree of recognizing the need of safety education textbooks, 295(38.5%) responded 'it was needed', on the recognition of necessity of teacher for safety education, 271(45.0%) answered it was very necessary', and on the recognition of qualification of teacher for safety education, 370(61.5%) answered it was 'paramedic'. The mean score of safety consciousness of subjects was 2.72 (SD. 21) of full score 3, having high score over mean score. According to each area, the area showing the highest safety consciousness was safety of fire(2.83), followed by home safety(2.76) and first-aid treatment(2.76), traffic safety(2.71), play and leisure safety(2.66) and school safety(2.56). Items showing statistical differences in the degree of safety consciousness according to demographical characteristics were sex(t=-3.11, p=.002), education(t=2.33, p=.021) and number of siblings(F=3.729, p=.011). In the difference of safety consciousness between both sexes, 'female' students(2.75) showed higher safety consciousness than 'male' students (2.69), and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of play and leisure safety, traffic safety, fire safety and first-aid treatment. According to the differences of safety consciousness by grade, 'the fifth graders'(2.74) showed higher safety consciousness than 'the sixth graders'(2.70) and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of fire safety and home safety. In the safety consciousness by the number of siblings, 'single son or daughter' (2.78) was highest and their safety consciousness was also highest in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of school safety, fire safety and home safety, There were statistically remarkable differences in degree of adaptation to school life (F=15.349, p=.000) and perceived schooling level(F=9.552, p=.000). According to the degree of safety consciousness related to characteristics of safety education, there were statistical differences at the degree of recognizing the need of safety education(F=9.797, p=.000), degree of safety education at school(F=2.595, p=.006), degree of safety education by parents(F=12.709, p=.000), degree of practicing safety by parents(F=17.579, p=.000), source of knowledge of safety education (F=2,715, p=.044), necessity of safety education textbooks(F=3.972, p=.008), need of safety teacher(F=4.137, p=.006) and qualification standard of safety teacher(F=3.016, p=.029).

• Journal of the Korean Geographical Society
• /
• v.31 no.3
• /
• pp.593-612
• /
• 1996

This study concern with the changes of street from the Choseon Dynasty to present days around Old-Boundary in Taegu, analyzing the backgrounds of change factors and development trends of the Taegu City. The basis element of a city structure is the street. Therefore, in this study, a chage of street space of a city was investigted. Historically, Taegu was a walled city and had a Mono-nucleus which was restricted by the castle, and served as a starting point of formation of spatial structuure. The form of the artery street took a "T" pattern, othe streets were formed in irregular shapes. As the city grew gradually, the castle was removed on account of diversification in traffic network, change of socio-economic organization in traffic network, change of socio-economic organization, formation of industrial bases and functional distribution. CBD of this city has been located within the area surrounded by these streets. This is a kind of general pattern of traditional walled cities through the world in both Western and Oriental societies. A s the begining of this centry, a 'Dark Ages' descended upon Korea because the country was under the Japanese-Korean Annexation, and, throughout this period, the urban planning was planned exclusively for Japanese. The street pattern within residential areas of Korea took the maze type, in contrast with Japanese residential areas which showed grid pattern of streets. This is another general pattern of almost of all colonial cities especially in Asia. High class residential areas were planned and built by Japanese, and they were located within 5-10 minutes' on-foot distance from the CBD hard core. This high prestige has continued until the 1980s when it occurred land use succession which commerical functions invaded into residential areas. Back in the colonial period, there was a between two hetrogeneous groups due to the fact that the Japanese lived mainly oriented the new railway system but that Koreans still lived along the old highway system which ran through the Korea Peninsula. Street netwook formed in the above process has maintained its shape without great changes after the liberation form the Japanese Colony. Taegu has, accordingly, developed ring-radial network system which has been a combination of radial and ring facilities. The present conditions of street patterns in Taegy mainly depend on 4 rings and 8 radius, with grid pattern street able to be found in Old Boundary.

• Journal of East-West Nursing Research
• /
• v.5 no.1
• /
• pp.90-101
• /
• 2000

The study attempts to examine the degree of cognition and demand on health promotion center of oriental nursing. It puts unique nursing intervention using traditional health promotion connected with oriental medicine to practical use for residents' health promotion and prevention of disease. With the study design of cross-sectional descriptive study, 516 residents who live in 26 Dongs, Dongdaemoon-gu were selected. The tool of study consists of 30 questions which the study team made for the degree of cognition and demand on health promotion center of oriental nursing. Cronbach's $\alpha$ in the degree of cognition was .8028. Collection of research data had been done from October 1 to October 30, 1999 with help of Dongdaemoon-gu office after pretest from 20 residents. Collected data were analyzed into the number and percentage in the characteristic of a subject and connected with demand on the establishment of center, the mean and the standard deviation in the degree of cognition and F-tests in the difference of the degree of cognition by characteristics. The results were as follow; 1) The characteristic of subject of this study was male 50.6%, and average age was 38.5 years old and 30-39 years old occupied the highest percentage with 31.6%. The married were 71.8%, over high school graduates was 85.6%, monthly income from 500 thousand won to 2 million won was 86.1%. 50.8% was the type living with parents, children and sibling. 2) When they were sick, the institution which residents used at first was a pharmacy(69.2%) and hospital(27.5%), but oriental medicine hospital was just 1.4%. As for subjective health condition, 82.5% answered over average, and 28.7% answered that they had chronic illness such as arthritis, chronic digestion problem, hypertension and so on. As for information collection on health, mass communication(34.9%) and medically concerned people(28.1%) occupied relatively high rate. Free health diagnosis system(36.8%) and establishment of health promotion center(31.5%) among welfare programs that residents want to enjoy were high ranked. The rate using a special institution for health was 17.8%, and among these institutions, the rate using aerobic exercises, health center(7.0%) and steamed room(5.4%) was high. Besides, other institutions such as breathing at the abdomen, finger-pressure therapy, meridian massage, foot massage, and so on were being used. 3) As the average of the degree of cognition on health promotion center of oriental medicine was 2.92, the degree of cognition was medium. The description, "health promotion center of oriental medicine is necessary for health keeping of healthy people, including people who have a problem in health" showed the highest degree of cognition(3.04, ${\pm}0.64$). 4) As for the intention on using health promotion center of oriental nursing, 61.4% said "yes", "no" was just 1.4%. The services that people relatively high wanted to be served from the center were measures reducing stress(68.0%) (relaxation therapy, meditation, breathing at the abdomen and so on), acupuncture(66.5%), finger-pressure(61.6%), moxibustion(57.6%), meridian massage(44.2%), postpartum care(40.3%) and so on. 5) As for the degree of cognition on the establishment of health promotion center of oriental nursing by characteristics of subject, there was significant difference(F=4.03, p=.046) between male(3.01) and female(2.91). But there was no significant difference by age, marital status, level of educational achievement and monthly income. As the above result, cognition on the establishment of health promotion center of oriental nursing was relatively low because people were not familiar with about the health promotion center of oriental nursing yet. However once the center will be established, the degree of demand on the center will be relatively high. So positive advertisement will be necessary, and the management of useful programs will be also required in order to make people recognize the advantage when they actually will use the center. On the other hand, as the subject of the study consists of many young people of below 30, the health problem came to be low. And in the case of sampling, the study using random sampling that can represent population will be required.

• Journal of Preventive Medicine and Public Health
• /
• v.27 no.3 s.47
• /
• pp.447-463
• /
• 1994

Despite the public health importance of injury and poisoning in terms of its high mortality and incidence, epidemiologic information to be utilized are scarce in Korea. This study was carried out in 1990 on a representative sample population (about 55,000 persons) along with the 6th National Tuberculosis Prevalence Survey in order to estimate the magnitude of injury and poisoning occurrence and to identify its epidemiologic characteristics which can be aided for establishing preventive strategy. Pre-tested and structured Questionnaire was used by trained interviewer to collect data including general information of the person, various information on the injury and poisoning during the past one year such as time and place of its occurrence, its nature and external causes, type of medical institute attended, duration of treatment and outcome of the accident occured. In analysis of the data collected incidence rates per 1000 persons by sex, age group and its nature as well as external causes, and relative frequencies were calculated. The result obtained are as followings; 1. The incidence rate per 1000 was 30 for both sexes, 39 for male and 22 for female, male being 1.8 times more frequent than female. Age adjusted incidences were not much different from the crude rates. Age group specific rate curve showed bimodal shape in both sexes, small peaks in preschool children and higher peaks in older ages. The incidence rate per 1000 people by area was highest in Jeon-bug province (57/1000) and the lowest in Daegu city(11/1000). 2. The place where the injuries occured were road in 46%, within the boundary of house in 25%, and working place in 12% The injuries and poisoning had occured more frequently during the months from March to August of the year than other months. 3. The relatively frequent injuries by its nature were contusion with intact skin surface (19%), fracture of upper limb (13%), open wound of head, neck and trunk (12%) and fracture of lower limb (11%) among males; contusion with intact skin surface (28%), sprains and strains of joints and adjacent muscle (14%), fracture of upper limb (10%) and fracture of lower limb (9%) among females. Higher incidence rate among males than females were fracture of skull (4.5 times), open wound and fractures of limbs ($2{\sim}3$ times). Age specific rate of injuries and poisoning by its nature showed increasing pattern by age in fractures of upper and lower limbs and sprains & strains of joints whereas the age group of 30's showed highest incidence in open wounds of upper limb. Fractures of radius and ulna in upper limb, fractures of tibia & fibula and ankle in lower limb were most frequent among fractures of upper and lower limbs. The frequent injuries among sprains and strains of joints and adjacent muscles were that of ankle, foot and back, and among open wound were that of head and fingers. 4. Relative frequency of injuries and poisoning by external causes showed following order : other accidents (25%), accidental falls (23%), motor vehicle accident (22%) and other road vehicle accident (14%) among males and accidental falls (37%), motor vehicle accident (24%) and other accident (18%) among females. The external causes revealing higher incidences among males than females, were other road vehicle accident (4.8 times), vehicle accident not elsewhere classifiable (4.4 times), accidental poisoning (4.4 times), accidents due to natural and environmental factors (2.8 times), and sucide & self-inflicted injuries (2.8 times). Age specific incidence by external causes for frequent injuries showed that incidence of other accident steadily increased from 10's till age 50's; motor vehicle traffic accident increased from age 20's and dropped after age 60's; on the other hand accidental fall increased strikingly by age. The most frequent external causes among motor vehicle traffic accidents was motor vehicle traffic accident involving collision with pedstrain (69%), pedal cycle accident (30%) and other road vehicle accident (71%) among other road vehicle accidents; falls on same level from slipping, tripping or standing (44%) and other falls from one level to another among accidental falls; accidents caused by machinary (32%) for male and striking against or struck accidentally by objects or person for female among other accidents. 5. Seventy nine percent of the injuries and poisonings were treated in general hospital or hospital/clinic. The duration of treatment ranged from a few days to 123 weeks; the majority(52%) took under 2 weeks, 36% for $3{\sim}8$ weeks and 4% over 21 weeks. 6. The accident resulted in full recovery of normal healthy state in 62%, residual functional defects in 21% and on process of treatment in 16%.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.2
• /
• pp.59-65
• /
• 2005

This study was performed to estimate the soil loss on a national scale and grade regions with the potential risk of soil erosion. Universal soil loss equation (USLE) for rainfall and runoff erosivity factors (R), cover management factors (C) and support practice factors (P) and revised USLE for soil erodibility factors (K) and topographic factors (LS) were used. To estimate the soil loss, the whole nation was divided into 21,337 groups according to city county, soil phase and land use type. The R factors were high in the southern coast of Gyeongnam and Jeonnam and part of the western coast of Gyeonggi and low in the inland and eastern coast of Gyeongbuk. The K factors were higher in the regions located on the lower streams of rivers and the plain lands of the western coast of Chungnam and Jeonbuk. The average slope of upland areas in Pyeongchang-gun was the steepest of 30.1%. The foot-slope areas from the Taebaek Mountains to the Sobaek Mountains had steep uplands. Total soil loss of Korea was estimated as $50{\times}10^6Mg$ in 2004. The potential risk of soil erosion in upland was the severest in Gyeongnam and the amount of soil erosion was the greatest in Jeonnam. The regions in which annual soil loss was estimated over $50Mg\;ha^{-1}$ were graded as "the very severe" and their acreage was $168{\times}10^3ha$ in 2004. The soil erosion maps of city/county of Korea were made based on digital soil maps with 1:25,000 scale.

• Journal of the Korean Burn Society
• /
• v.24 no.2
• /
• pp.21-29
• /
• 2021

Purpose: Frostbite is a hazard to people exposed to cold environments. With the progression of modern industrial development and change of leisure behavior encountering cold environments, frequent accidental exposure to frostbite injury during work and human behavior is increasing, and the predisposing factors of frostbite were greatly changed than before. The purpose of this study was to make epidemiological analysis, and to review the treatment outcomes of frostbite. Methods: From March 2010 to February 2021, this study has included 27 patients with second- to third-degree frostbite injuries in Advanced Burn Reconstruction Center, Bundang Jesaeng Hosptial. A retrospective study was made about the distribution of age, gender, predisposing factors, prevalent area, type of managements, and the length of treatment period. Results: In our institution, acute management of frostbite patients has included rewarming, anticoagulation therapy (acetylsalicylic acid), and agents to improve vascular perfusion (lipo-prostaglandin E1 [Eglandin^®]). The 25 frostbite patients with second-degree frostbite (92.6%) were successfully managed by the conservative treatment alone with a mean of 20.3 days healing time. Two patients with third-degree frostbite (7.4%) also showed good outcomes after surgical reconstruction with a mean of 59 days healing time. In our clinical experiences of third-degree frostbite, definitive surgical reconstruction should be recommended to wait for more than 4~6 weeks for identification of clear demarcation of necrotic tissue caused by frostbite. In this study, 43 frostbite injuries site in 27 frostbite patients occurred. Among them, 15 patients (55.6%) had multiple-site frostbite injury. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments (40.8%), misapplying ice pack for treatment purposes (7.4%), barefoot walking on the cold ground (3.7%), and loss of consciousness in cold grounds (3.7%). The most prevalent sites of frostbite injuries revealed as the hand (58.1%), followed by the foot (32.6%), face (7.0%), and abdomen (2.3%). And in the winter season from the November to March, the incidence rate of frostbite injuries was high at 74.1%. Conclusion: This study included 27 frostbite patients with 43 frostbite sites since last decade in a single institution at the community hospital. The frostbite patients with second-degree frostbite (92.6%) were successfully healed by the conservative treatment alone with a mean of 20.3 days healing time. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments, etc. The most prevalent site of frostbite injuries was the hand (58.1%). And the most prevalent seasonal incidence of frostbite was from November to March (74.1%).

• Journal of Society of Preventive Korean Medicine
• /
• v.5 no.2
• /
• pp.40-68
• /
• 2001

In this study, grade of subjective symptom appealed by laborer of Jeollabuk-do was evaluated using questionary regarding factor made effect on musculoskeletal disease and in addition, studied relationship with health promotion life style of them. Based on the result, relationship of general characteristics of musculoskeletal subjective symptom and life-style of the subjects was concluded as below. 1. General characteristics of study subjects were as following. Ratio of male was higher as 57.7% of male and 42.2% female and age distribution was 5.1% of 20s, 34.99% of 30s, 36.3% of 40s and 23.7% of 50s and therefore, $30{\sim}40$ aged groups showed highest ratio. Most subjects (74.9%) was married status and in case of education level, high-school graduate and dropout (23.3%) and over-college graduate (46.8%) showed highest distribution. $1{\sim}2$ Mil. KRW (29.5%) and $2{\sim}2.99$ Mil. KRW (21.2%) is the main income distribution and however there was high ratio of non-reply (29.0%). In case of employment period, $10{\sim}14$ years (15.3%) and over 15 years (29.6%) showed highest ratio and there were many non-reply (39.4%) and in addition, 67.6% replied as own house and 14.3% as lease on deposit base in question of residence type. 2. Subjects showed high ratio of subjective symptom appeal of 62.79% and many cases (50.23%) appealed 1 or 2 symptoms. Symptom by body region was 29.8% (waist), 27% (shoulder), 21.2% (knee), 15.5% (neck), 9.5% (ankle), 8.1% (wrist) and 5.0% (elbow) in order. In case of relationship with general characteristics, female comparing with male, non-residence of own house, subjects with lower education level and employment period of $10{\sim}14$ years showed higher appeal rate and kind of symptoms than others. Therefore, it was concluded that rate of musculoskeletal symptom appeal have close relationship with gender, level of living, education level, age and employment period. 3. In case of severe pain of upper body except waist and ankle, it was appealed in both or right side and it means that upper body pain is originated from right side and right region pain is transited to both region pain. In addition, there was 39.41% of non-reply to existence of right-left region pain and therefore, it was evaluated that, in may cases, there was no awareness of their own symptom condition even on subjective symptom. 4. Degree of pain was, as pain over middle level, evaluated as 2.79 on full mark of 4.0 and in order of waist (2.97), ankle (2.83), knee (2.82), wrist (2.82), neck (2.79), shoulder (2.70) and elbow (2.62). In addition, 71.97% appealed $2{\sim}3$ cases for the latest 1 week. Owing to subjective symptom, 54.95% drop into hospital or pharmacy, 10.32% made temporary retirement or absence, 7.99% transferred into more comfortable duty and $39.4{\sim}54%$ experienced one or more managing mentioned above. 5. Fulfillment of health promotion life style of subjects was evaluated on full mark of 4.0 and total score was 2.63. Average mark of each area was personal relationship (3.05), self-realization (2.92), stress management (2.63), health control (2.48), physical exercise (2.19) and nutrition management (2.19) and personal relationship was highest and physical exercise and nutrition management were lowest. As general characteristics influencing health promotion life style, gender, residence style and employment period showed significant difference. Male showed higher mark than female and showed higher mark in order of own house, others, lease on deposit base, monthly rent. Subjects with longer employment period showed higher mark with significant difference. 6. Accounting of factor influencing each area of health promotion life style, self-realization showed significance in marriage status, income, residence style and education level and health control in age, residence style and employment period. Physical exercise showed significant difference in gender, age, residence style and employment period and nutrition in gender, age, residence style and employment period. Stress management showed significant difference in residence style and employment period and however not in personal relationship. 7. Health promotion life style relating with existence and kind of pain showed significant difference in all area except personal relationship area. In absence of pain, there was statistically significant high score in all area even in total health promotion life style and all area. Accounting of kind of pain, cases of $1{\sim}2$ kinds of pain and $5{\sim}6$ kinds of pain showed relatively high score and it was lower than mark of subject stated absence of pain. 8. Subjects appeal symptom were classified by symptom region and difference of total and each areas were evaluated. General area (p=0.002), self-realization (p=0.012), health management (p=0.023), physical exercise (p=0.028), nutrition management (p=0.028) and stress control (p=0.001) showed statistically significant difference and not in personal relationship area. Especially, elbow, shoulder and neck area marked high and group appealed pain of knee, arm and elbow, foot and ankle marked low. Based on those results, subjective symptom should be accounted seriously in diagnosis of occupational musculoskeletal disease of laborer and among subjective symptom, general characteristics of gender, age, condition of living, education level and employment period make effect. Generally subject appeal symptom marked lower than subject without symptom appeal and it means that life management of subject appealing musculoskeletal pain make important role in management and treatment of occupational musculoskeletal disease.

• Journal of Preventive Medicine and Public Health
• /
• v.27 no.2 s.46
• /
• pp.258-273
• /
• 1994

To compare the physical complaints of vinylhouse farmers with those of non-vinylhouse farmers, a personal interviews on 250 vinylhouse and 142 non-vinylhouse farmers were conducted in Sungjoo county in Kyungpook province selected by a random sampling from July 5 to July 10, 1993. Blood pressure of the subjects was also measured. Vinylhouse farmers had a higher average age, larger family size, shorter experience of farming, more working hours per day and working days per year and higher annual income than the non-vinylhouse farmers. The frequency of pesticide spray of the vinylhouse farmers was 3.4 times on the average in June 1993 as compared with 2.0 times of non-vinylhouse farmers, and 16.7 times for the vinylhouse farmers during the last one year while it was 8.3 times for the non-vinylhouse farmers in the same period. While 39.6% of vinylhouse farmers experienced pesticide intoxication symptoms such as headache, nausea, vomiting, dizziness, itching, and skin irritation, etc. during the month of June, 25.4% of non-vinylhouse farmers experienced such symptoms. The most frequent symptoms among eight symptoms that constitute the farmers' syndrome were lumbago, numbness of hand or foot, shoulder pain and dizziness regardless of sex and type of farming. Prevalence of the farmers' syndrome in male and female among vinylhouse farmers were 22.1%, 43.4%, respectively, and the prevalence in non-vinylhouse farmers was 23.2% for male and 50.7% for female. There was no statistically significant difference in the prevalence of farmers' syndrome between vinylhouse and non-vinylhouse farmers. However, the prevalence in female was about 2 times higher than that of male. When the effects of other factors were adjusted by multiple logistic regression for farmers' syndrome, the prevalence in female was 3.0 times higher than that of male. The prevalence of farmers' syndrome was increased as the age of farmers increased in both vinylhouse and non-vinylhouse farmers, and adjusted odds ratio of farmers' syndrome increased by 3% as the age increased by 1 year. Adjusted odds ratio for Farmers' syndrome in farmers who experienced pesticide intoxication during the month of June was 3.1 times higher than that of farmers who did not have such experience. While the prevalence of hypertension in male and female non-vinylhouse farmers were 22.4%, 13.7%, respectively, the prevalence in vinylhouse farmers were 13.5% for male and 12.0% for female. However, there was no association between farmers' syndrome and hypertension. It was found in this study that the vinylhouse farmers are at a high risk of pesticide intoxication, which is associated with tile common physical complaints. To reduce such risk it is necessary to develop farming methods which do not require the pesticide or may use less pesticide, a safer method of pesticide spraying, and the protective equipments which can be worn at a high temperature and have a better protective effect. Also education of farmers for the correct methods of ventilation after pesticide spraying in the vinylhouse and wearing the protective equipments may be considered as a supportive method. Since inappropriate posture at work and intensive labor may cause farmers' syndrome, it is recommended to develop farming tools which reduce physical burden and take a rest and exercise periodically during work. It is necessary to strengthen the hypertension management program of the Kyungpook province, because the prevalence of hypertension was as high as about 15%.

• Journal of Korean Society of Forest Science
• /
• v.66 no.1
• /
• pp.16-36
• /
• 1984

It is very important in forestry to study the shear strength of weathered granitic soil, because the soil covers 66% of our country, and because the majority of land slides have been occured in the soil. In general, the causes of land slide can be classified both the external and internal factors. The external factors are known as vegetations, geography and climate, but internal factors are known as engineering properties originated from parent rocks and weathering. Soil engineering properties are controlled by the skeleton structure, texture, consistency, cohesion, permeability, water content, mineral components, porosity and density etc. of soils. And the effects of these internal factors on sliding down summarize as resistance, shear strength, against silding of soil mass. Shear strength basically depends upon effective stress, kinds of soils, density (void ratio), water content, the structure and arrangement of soil particles, among the properties. But these elements of shear strength work not all alone, but together. The purpose of this thesis is to clarify the characteristics of shear strength and the related elements, such as water content ($w_o$), void ratio($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$), and the interrelationship among related elements in order to decide the dominant element chiefly influencing on shear strength in natural/undisturbed state of weathered granitic soil, in addition to the characteristics of soil hardness of weathered granitic soil and root distribution of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands. For the characteristics of shear strength of weathered granitic soil and the related elements of shear strength, three sites were selected from Kwangju district. The outlines of sampling sites in the district were: average specific gravity, 2.63 ~ 2.79; average natural water content, 24.3 ~ 28.3%; average dry density, $1.31{\sim}1.43g/cm^3$, average void ratio, 0.93 ~ 1.001 ; cohesion, $ 0.2{\sim}0.75kg/cm^2$ ; angle of internal friction, $29^{\circ}{\sim}45^{\circ}$ ; soil texture, SL. The shear strength of the soil in different sites was measured by a direct shear apparatus (type B; shear box size, $62.5{\times}20mm$; ${\sigma}$, $1.434kg/cm^2$; speed, 1/100mm/min.). For the related element analyses, water content was moderated through a series of drainage experiments with 4 levels of drainage period, specific gravity was measured by KS F 308, analysis of particle size distribution, by KS F 2302 and soil samples were dried at $110{\pm}5^{\circ}C$ for more than 12 hours in dry oven. Soil hardness represents physical properties, such as particle size distribution, porosity, bulk density and water content of soil, and test of the hardness by soil hardness tester is the simplest approach and totally indicative method to grasp the mechanical properties of soil. It is important to understand the mechanical properties of soil as well as the chemical in order to realize the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to study the correlation between the soil hardness and the distribution of tree roots of Pinus rigida Mill. planted in 1966 and Pinus rigida ${\times}$ taeda in 199 to 1960 in the denuded forest lands with and after several erosion control works. The soil texture of the sites investigated was SL originated from weathered granitic soil. The former is situated at Py$\ddot{o}$ngchangri, Ky$\ddot{o}$m-my$\ddot{o}$n, Kogs$\ddot{o}$ng-gun, Ch$\ddot{o}$llanam-do (3.63 ha; slope, $17^{\circ}{\sim}41^{\circ}$ soil depth, thin or medium; humidity, dry or optimum; height, 5.66/3.73 ~ 7.63 m; D.B.H., 9.7/8.00 ~ 12.00 cm) and the Latter at changun-long Kwangju-shi (3.50 ha; slope, $12^{\circ}{\sim}23^{\circ}$; soil depth, thin; humidity, dry; height, 10.47/7.3 ~ 12.79 m; D.B.H., 16.94/14.3 ~ 19.4 cm).The sampling areas were 24quadrats ($10m{\times}10m$) in the former area and 12 in the latter expanding from summit to foot. Each sampling trees for hardness test and investigation of root distribution were selected by purposive selection and soil profiles of these trees were made at the downward distance of 50 cm from the trees, at each quadrat. Soil layers of the profile were separated by the distance of 10 cm from the surface (layer I, II, ... ...). Soil hardness was measured with Yamanaka soil hardness tester and indicated as indicated soil hardness at the different soil layers. The distribution of tree root number per unit area in different soil depth was investigated, and the relationship between the soil hardness and the number of tree roots was discussed. The results obtained from the experiments are summarized as follows. 1. Analyses of simple relationship between shear strength and elements of shear strength, water content ($w_o$), void ratio ($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$). 1) Negative correlation coefficients were recognized between shear strength and water content. and shear strength and void ratio. 2) Positive correlation coefficients were recognized between shear strength and dry density. 3) The correlation coefficients between shear strength and specific gravity were not significant. 2. Analyses of partial and multiple correlation coefficients between shear strength and the related elements: 1) From the analyses of the partial correlation coefficients among water content ($x_1$), void ratio ($x_2$), and dry density ($x_3$), the direct effect of the water content on shear strength was the highest, and effect on shear strength was in order of void ratio and dry density. Similar trend was recognized from the results of multiple correlation coefficient analyses. 2) Multiple linear regression equations derived from two independent variables, water content ($x_1$ and dry density ($x_2$) were found to be ineffective in estimating shear strength ($\hat{Y}$). However, the simple linear regression equations with an independent variable, water content (x) were highly efficient to estimate shear strength ($\hat{Y}$) with relatively high fitness. 3. A relationship between soil hardness and the distribution of root number: 1) The soil hardness increased proportionally to the soil depth. Negative correlation coefficients were recognized between indicated soil hardness and the number of tree roots in both plantations. 2) The majority of tree roots of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands distributed at 20 cm deep from the surface. 3) Simple linear regression equations were derived from indicated hardness (x) and the number of tree roots (Y) to estimate root numbers in both plantations.

• Journal of Korean Society of Forest Science
• /
• v.62 no.1
• /
• pp.24-42
• /
• 1983

To develop Ilex cornuta which grow naturally in the southwest seaside district as new ornamental tree, the author chose I. cornuta growing in the four natural communities and those cultivated in Kwangju city as a sample, and investigated its ecology, morphology and characteristics. The results obtained was summarized as follows; 1) The natural distribution of I. cornuta marks $35^{\circ}$43'N and $126^{\circ}$44'E in the southwestern part of Korea and $33^{\circ}$20'N and $126^{\circ}$15'E in Jejoo island. This area has the following necessary conditions for Ilex cornuta: the annual average temperature is above $12^{\circ}C$, the coldness index below $-12.7^{\circ}C$, annual average relative humidity 75-80%, and the number of snow-covering days is 20-25 days, situated within 20km of from coastline and within, 100m above sea level and mainly at the foot of the mountain facing the southeast. 2) The vegetation in I. cornuta community can be divided that upper layer is composed of Pinus thunbergii and P. densiflora, middle layer of Eurya japonica var. montana, Ilex cornuta and Vaccinium bracteatum, and the ground vegetation is composed of Carex lanceolata and Arundinella hirta var. ciliare. The community has high species diversity which indicates it is at the stage of development. Although I. cornuta is a species of the southern type of temperate zone where coniferous tree or broad leaved, evergreen trees grow together, it occasionally grows in the subtropical zone. 3) Parent rock is gneiss or rhyolite etc., and soil is acidic (about pH 4.5-5.0) and the content of available phosphorus is low. 4) At maturity, the height growth averaged $10.48{\pm}0.23cm$ a year and the diameter growth 0.43 cm a year, and the annual ring was not clear. Mean leaf-number was 11.34. There are a significant positive correlation between twig-elongation and leaf-number. 5) One-year-old seedling grows up to 10.66 cm (max. 18.2 cm, min. 4.0 cm) in shoot-height, with its leaf number 12.1 (max. 18, min), its basal diameter 2.24 mm (max. 4.0 mm, min. 1.0 mm) and shows rhythmical growth in high temperature period. There were significant positive correlations between stalk-height and leaf-number, between stalk-height and basal-diameter, and between number and basal diameter. 6) The flowering time ranged from the end of April to the beginning of May, and the flower has tetra-merouscorella and corymb of yellowish green. It has a bisexual flower and dioecism with a sexual ratio 1:1. 7) The fruit, after fertilization, grows 0.87 cm long (0.61-1.31 cm) and 0.8 cm wide (0.62-1.05 cm) by the beginning of May. Fruits begin to turn red and continue to ripen until the end of October or the beginning of November and remain unfading until the end of following May. With the partial change in color of dark-brown at the beginning of the June fruits begin to fall, bur some remain even after three years. 8) The seed acquision ratio is 24.7% by weight, and the number of grains per fruit averages 3.9 and the seed weight per liter is 114.2 gram, while the average weight of 1,000 seeds is 24.56 grams. 9) Seeds after complete removal of sarcocarp, were buried under ground in a fixed temperature and humidity and they began to develop root in October, a year later and germinated in the next April. Under sunlight or drought, however, the dormant state may be continued.