• Asian review of World Histories
• /
• 제3권2호
• /
• pp.171-200
• /
• 2015

At its simplest, this essay provides a narrative of migration in Asia since the arrival of Homo sapiens some 70,000 years ago. More fully, it presents the case for conducting long-term, world-historical interpretation for Asia with attention to multiple perspectives, which has become increasingly central to global historical analysis. Following an introductory articulation of the benefits of long-term interpretation, the second section presents a balance of three perspectives-empire, exchange, and migration-as frameworks for interpreting the Asian past. The third section presents further detail on migration in long-term Asian history. The concluding section identifies four changes in patterns of migration during the past two centuries and emphasizes the underlying importance of cross-community migration in long-term human biological and social evolution.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2005년도 춘계 학술발표회 논문집
• /
• pp.439-444
• /
• 2005

Shotcrete lining is likely to be deteriorated due to the ground water which the lining is exposed to. Some tunnel collapses seemed to be affected by shotcrete degradation were reported. But there isn't any assessment method of shotcret long-term degradation. So, Experimental technology for shotcrete long-term degradation modeling was developed in this study. The shotcrete long-term degradation modeling, developed in other study in Korea Institute of Construction Technology, require the time-history of volume change. Digital strain observation system was used to acquire the time-history of volume change. To verify the Strain Observation Digital System, the measurement using the system was compared to the one using a micrometer. Through this process, The experiment for shotcrete long-term degradation modeling was set up.

• Journal of Information Technology Applications and Management
• /
• 제29권5호
• /
• pp.27-37
• /
• 2022

This study intends to link agricultural machine history data with related organizations or collect them through IoT sensors, receive input from agricultural machine users and managers, and analyze them through AI algorithms. Through this, the goal is to track and manage the history data throughout all stages of production, purchase, operation, and disposal of agricultural machinery. First, LSTM (Long Short-Term Memory) is used to estimate oil consumption and recommend maintenance from historical data of agricultural machines such as tractors and combines, and C-LSTM (Convolution Long Short-Term Memory) is used to diagnose and determine failures. Memory) to build a deep learning algorithm. Second, in order to collect historical data of agricultural machinery, IoT sensors including GPS module, gyro sensor, acceleration sensor, and temperature and humidity sensor are attached to agricultural machinery to automatically collect data. Third, event-type data such as agricultural machine production, purchase, and disposal are automatically collected from related organizations to design an interface that can integrate the entire life cycle history data and collect data through this.

• 대한가정학회지
• /
• 제38권1호
• /
• pp.59-73
• /
• 2000

The purposes of this study were to determine the factors that influence consumer concerns for safety to cow's milk produced using food-related biotechnology and to find the similarity and difference among concern factors relating short-term and long-term risk perception. Telephone interviews were conducted and the data were collected from households(n=1,466) nationwide in the U.S. And the data were analyzed by probit model and LIMDEP softare package. The data demonstrated that consumers were concerned about food safety from consuming milk produced using food-related biotechnology. The concerns were found to be influenced by demographic factors(gender in short-term, gender and age in long-term) as well as psychological aspect such as outrage(heard about bGH, milk belief about naturalness, expected benefit in short-term, heard about bGH, expected benefit in long-term) and attitudinal factors(animal rights group, locus of control in short-term, animal rights group, cancer history, locus of control in long-term). The results suggest that consumers have concerns for safety to cow's milk produced by biotechnology and the most factors influencing consumer concerns were similar between short-term and long-term period, though a few factors such as cancer history, milk belief about naturalness and age were different.

• 한국산림과학회지
• /
• 제109권4호
• /
• pp.544-552
• /
• 2020

본 연구는 국립산림치유원에서 2019년 진행된 장기체류 산림치유프로그램 「숲 속 힐링스테이」에 참가한 49명을 대상으로, 참여 전·후 설문조사 및 혈압, 체성분, HRV 등 신체변화를 측정하여 프로그램의 효과성을 분석했다. 연구결과, 장기체류 산림치유프로그램 참여 후에 참여자의 부정감정이 통계적으로 유의하게 감소하였고, 자율신경 균형도는 통계적으로 유의하게 증진되어 긍정적인 효과를 확인할 수 있었다. 병력 유무에 따른 체력측정 변화를 살펴본 결과 악력 및 제자리높이뛰기 증가 정도가 통계적으로 유의한 차이가 있었으며, 병력이 있는 사람들이 병력이 없는 사람들에 비해 증진 효과가 더 높게 나타났다. 본 연구에서는 단기형 프로그램 효과검증에서 벗어나 6박7일 장기체류 형태의 산림치유 효과성을 확인한 것에 그 의의가 있다.

• 대한간호학회지
• /
• 제30권1호
• /
• pp.29-38
• /
• 2000

To determine whether personal history of lactation in premenopausal women influence bone mineral density, a cross-sectional study was conducted. One hundred eighty-four premenopausal women were selected from women who had been checked for bone mineral density by dual energy x-ray absortiometry in lumbar spine, femoral neck, Ward's triangle, and trochanteric site at general hospitals in Seoul and Pusan. They completed a questionnaire including life style factors and reproductive history. In the data analysis, Pearson correlation coefficients were used to test any association between individual variables and bone mineral density and a statistical comparisons between long term lactation(>24 months) and short term lactation(<24 months) were made by one way analysis of covariance. The results were summarized as follows: 1) There was no significant difference in the bone mineral density of the lumbar vertebrae in premenopausal women between the long term lactation group(>24months) and the short term lactation group(<24months). 2) There was no significant difference in the bone mineral density of the femur neck, Ward's triangle, and trochanteric site in premenopausal women between the long term lactation group (>24months) and the short term lactation group (<24months). Considering these results, we suggest prospective studies that measure bone mineral density before and after, in addition to those during lactation. We also suggest the further study with premenopausal women less than 35 who have achieved peak adult bone mass.

• 한국안전학회지
• /
• 제15권4호
• /
• pp.35-40
• /
• 2000

The influence of cyclic loading history on the creep behavior of the 30 vol% hot-pressed $SiC_f/Si_3N_4copmposite was experimentally investigated at $1200^{\circ}C$. The duration of loading/unloading had great effects on the creep behaviors. The short term duration cyclic loading history test results showed significant reduction in the primary and steady-state creep rates. For example, 300sec loading/300sec unloading history resulted in 70% lower steady-state creep rate than that of the continuous loading. However the long term duration cyclic loading history test results showed little change in creep rates compared to those of the continuous one. The reason for the significant change in the short term duration cycles was estimated due to the change in the stress redistribution between the fiber and matrix during the creep recovery in the primary stage.

• Structural Engineering and Mechanics
• /
• 제20권2호
• /
• pp.173-189
• /
• 2005

The paper presents a finite element model for studying timber-concrete composite beams under long-term loading. Both deformability of connection system and rheological behaviour of concrete, timber and connection are fully considered. The creep of component materials and the influence of moisture content on the creep of timber and connection, the so-called "mechano-sorptive" effect, are evaluated by means of accurate linear models. The solution is obtained by applying an effective step-by-step procedure in time, which does not require storing the whole stress history in some points in order to account for the creep behaviour. Hence the proposed method is suitable for analyses of composite beams subjected to complex loading and thermo-hygrometric histories. The possibility to accurately predict the long-term response is then shown by comparing numerical and experimental results for different tests.

• Journal of Digestive Cancer Research
• /
• 제10권1호
• /
• pp.9-15
• /
• 2022

Proton pump inhibitors (PPIs), a potent gastric acid inhibitor, are widely used in gastric acid-related diseases such as gastroesophageal reflux disease and peptic ulcer, and are known as the most frequently used drugs worldwide. However, as the frequency of use increases, the number of cases of long-term PPI therapy without clear indications is increasing. Recently, there have been concerns about the risk of gastric cancer in patients with long-term PPI users. Potential mechanisms for the association between PPI and gastric cancer include enterochromaffin-like cell proliferation due to hypergastrinemia caused by gastric acid suppression, progression of atrophic gastritis, and corpus-predominant type through interaction with Helicobacter pylori (H. pylori) infection. Several epidemiologic studies showed controversial results on the issue, and it is difficult to prove a causal relationship between PPI and gastric cancer. Nevertheless, long-term PPI should be administered cautiously based on individual risk-benefit profile, specifically among those with history of H. pylori infection, in high-risk region of gastric cancer.

• 한국방사성폐기물학회:학술대회논문집
• /
• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
• /
• pp.331-332
• /
• 2019