• Korean Journal of Radiology
• /
• v.22 no.5
• /
• pp.770-781
• /
• 2021

Objective: Chemical exchange-dependent saturation transfer (CEST) MRI is sensitive for detecting solid-like proteins and may detect changes in the levels of mobile proteins and peptides in tissues. The objective of this study was to evaluate the characteristics of chemical exchange proton pools using the CEST MRI technique in patients with dementia. Materials and Methods: Our institutional review board approved this cross-sectional prospective study and informed consent was obtained from all participants. This study included 41 subjects (19 with dementia and 22 without dementia). Complete CEST data of the brain were obtained using a three-dimensional gradient and spin-echo sequence to map CEST indices, such as amide, amine, hydroxyl, and magnetization transfer ratio asymmetry (MTR_asym) values, using six-pool Lorentzian fitting. Statistical analyses of CEST indices were performed to evaluate group comparisons, their correlations with gray matter volume (GMV) and Mini-Mental State Examination (MMSE) scores, and receiver operating characteristic (ROC) curves. Results: Amine signals (0.029 for non-dementia, 0.046 for dementia, p = 0.011 at hippocampus) and MTR_asym values at 3 ppm (0.748 for non-dementia, 1.138 for dementia, p = 0.022 at hippocampus), and 3.5 ppm (0.463 for non-dementia, 0.875 for dementia, p = 0.029 at hippocampus) were significantly higher in the dementia group than in the non-dementia group. Most CEST indices were not significantly correlated with GMV; however, except amide, most indices were significantly correlated with the MMSE scores. The classification power of most CEST indices was lower than that of GMV but adding one of the CEST indices in GMV improved the classification between the subject groups. The largest improvement was seen in the MTR_asym values at 2 ppm in the anterior cingulate (area under the ROC curve = 0.981), with a sensitivity of 100 and a specificity of 90.91. Conclusion: CEST MRI potentially allows noninvasive image alterations in the Alzheimer's disease brain without injecting isotopes for monitoring different disease states and may provide a new imaging biomarker in the future.

• Annals of Occupational and Environmental Medicine
• /
• v.35
• /
• pp.24.1-24.15
• /
• 2023

Background: The construction workers are vulnerable to fatigue due to high physical workload. This study aimed to investigate the relationship between overwork and heart rate in construction workers and propose a scheme to prevent overwork in advance. Methods: We measured the heart rates of construction workers at a construction site of a residential and commercial complex in Seoul from August to October 2021 and develop an index that monitors overwork in real-time. A total of 66 Korean workers participated in the study, wearing real-time heart rate monitoring equipment. The relative heart rate (RHR) was calculated using the minimum and maximum heart rates, and the maximum acceptable working time (MAWT) was estimated using RHR to calculate the workload. The overwork index (OI) was defined as the cumulative workload evaluated with the MAWT. An appropriate scenario line (PSL) was set as an index that can be compared to the OI to evaluate the degree of overwork in real-time. The excess overwork index (EOI) was evaluated in real-time during work performance using the difference between the OI and the PSL. The EOI value was used to perform receiver operating characteristic (ROC) curve analysis to find the optimal cut-off value for classification of overwork state. Results: Of the 60 participants analyzed, 28 (46.7%) were classified as the overwork group based on their RHR. ROC curve analysis showed that the EOI was a good predictor of overwork, with an area under the curve of 0.824. The optimal cut-off values ranged from 21.8% to 24.0% depending on the method used to determine the cut-off point. Conclusion: The EOI showed promising results as a predictive tool to assess overwork in real-time using heart rate monitoring and calculation through MAWT. Further research is needed to assess physical workload accurately and determine cut-off values across industries.

• Journal of Digital Convergence
• /
• v.22 no.1
• /
• pp.1-14
• /
• 2024

In order to improve the effectiveness of carbon neutrality in Jeju Special Self-Governing Province, this study identifies the current state of social environmental education through literature research, excluding school environmental education being implemented in elementary, middle, and high schools in the province, and identifies shortcomings or problems. The purpose is to establish a plan to systematically and integratedly operate social environmental education, and the derived plan can be used as a guide to change environmental awareness and induce eco-friendly behavior to improve the effectiveness of carbon neutrality. As a result of the study, Jeju Special Self-Governing Province established a consultative body with environmental education institutions, organizations and expert groups operating dispersed throughout the province through the substantial operation and support of the environmental education center currently being entrusted, to identify the current status and develop content necessary for establishing environmental education policies, establishing a platform to enable information sharing, role division, regular communication, empathy, and policy feedback, and on-site environmental education centered on the field to stimulate emotions and personalize environmental problems so that environmental problems can be properly recognized. Emphasizing the necessity.

• 보존과학연구
• /
• s.25
• /
• pp.119-132
• /
• 2004

Annals of the Joseon Dynasty is the authentic record of the historical facts and events taken place throughout the entire period of 472 years(25 generations, 1392~1863)described in a chronological order. The tremendous volume of the records contains the factual events taken place in almost all the fields of the Joseon Dynasty ranging from politics, economy to history of the dynasty. Not only because of its affluent contents but also with the precision of its records, it was designated as the National Treasure No. 151 in1973 by the Korean government and also registered as the Memory of the World by UNESCO in October 1997.This study is to report a exhaustive investigation results on the conservation state of annals of the Joseon Dynasty, especially Mt. Jeongjoksan edition, under the storage of the Kyujanggak in order to obtain the current condition, and thereby to estimate the any deterioration of the waxed volumes in the future. According to results of the investigation, we are going to verify damage causes of annals of the Joseon Dynasty, and to consider scientific conservation methods for the permanent preservation of invaluable cultural heritage. The major problem with the preservation of annals has arisen particularly from the deterioration of the waxed volumes of the Mt. Jeongjoksan edition. In order to provide for the counter measures for this problem, we have conducted twice investigations(first :1998~1999, second : 2003) to the internal and external conditions of waxed volumes(Annals of King Taejo~Annals of King Myeongjong).The result of the investigation has indicated that the paper quality of the some of the waxed volumes (Annals of King Taejong~Annals of King Sejong) is cracked and folded and the pages are imbedded to each other due to the hardened or congealed wax on the paper. Some of the pages are even getting moldy. And in order to detect as to whether“ there has been any deterioration progressed to the waxed books in the modern storage facility of the Kyujanggak equipped with constant temperature and humidity condition, the first investigation(1998~1999) and the second investigation(2003) have recorded the values of acidity, whiteness and moisture rate of the waxed paper, reporting an observation that there has been no difference on the measuring items. This indicates that no virtual deterioration has been progressed so far to the waxed volumes preserved in the Kyujanggak. Also, except for the causes of deterioration to the paper by insects and microorganisms, the major cause for the paper damage seems to the change of moisture of the paper caused from the alteration of the temperature and humidity of the storage environment. With this understanding in mind, we have conducted an environmental investigation on the three selected points of the storage in the aspects of the temperature, humidity, air current, $CO_2$,HCHO, and $SO_2$.It has been observed that the temperature stood at $16.9^{\circ}C~20.2^{\circ}C$ and the humidity was stable between 53%~56% during the period of the investigation. The concentration of the carbon monoxide and carbon dioxide of the storage were very similar to those in the air. These data lead to presume that there is no problem in the aspect of carbon oxidization. But the concentration of sulfur dioxide, hydrogen sulfide and formaldehyde of the storage were detected a little higher than those of standard. Therefore, we consider that it is necessary to ventilate the internal air of the store room by means of operating air purification devices.

• Journal of Korean Biological Nursing Science
• /
• v.4 no.1
• /
• pp.41-49
• /
• 2002

The purpose of this study was to identify the knowledge contents of basic nursing sciences needed by nurses in the practices of the intensive care unit(ICU). To attain the goal of this study, the nurses working at 10 hospitals in the areas of Seoul and Kangwon Province were randomly selected. They were primarily interviewed, and the open question was secondarily put to them through the questionnaire. In the process of the 1st interview, the interviewees were asked of the question, "What is the knowledge of basic sciences such as anatomy, pathology, physiology. microbiology, pharmacology and the like thought to be lacking when you communicate with doctors in the ICU and when you carry out your nursing practices in it?" The contents of the interview were tape-recorded. The period of data collection ranged from May 1, 2001 to Sept 30. The interviews were conducted with total of 20 nurses. The open-end questionnaire was secondarily mailed to nurses. 113 questionnaires were returned. 100 questionnaires except 13 ones thought to be poorly completed in content were used for data analysis. Three coders classified data obtained from the interview and the questionnaire research into 5 detailed items relating to such as anatomical physiology, pathology, pharmacology. microbiology and basics of nursing. The three coders had experiences in nursing education of 18 years, 8 years and 6 years, respectively, and of them one coder was professor in basic nursing sciences. Data were statistically treated using frequency analysis and percentage by the SAS program. As a result, the following findings were obtained : It was found that the contents that ICU nurses responded were most needed in the field of Human structure and function were water and electrolytic balance(38%), blood and circulatory system(20%), changer in the patient's skin(12%), the arrangement of the human body(10%) and the endocrine system(10%), nervous system(6%), and assessment of the state of the patient's consciousness(4%). It was found that the contents that ICU nurses responded were most needed in the field of pathology were found to be the process of the progress of the disease(32%), symptoms of the disease(27%), prognosis of the disease(22%), followed by the injury-healing process, clinical pathological examination, and examination by radiation. It was found that the contents that nurses responded were most needed in the field of pharmacology were the effect of drug(25%), the side effect of drug(22%), the relationship between diseases and drug(20%), the relationship between disease-causing bacteria and drug(20%) and chemotherapy(2%). It was found that the contents that ICU nurses responded were most needed in the field of microbiology were the relationship between diseases and disease-causing bacteria(45%), Kinds and characteristics of disease-causing bacteria(18%), infection control(16%), application of the aseptic technique(12%), isolation(9%) and the like. It was found that the basic knowledge that ICU nurses responded were needed were the identification of the patient's current state(36%), understanding of the therapeutic process(22%), the operating principle of medical equipment and instrument(20%), medical terminology(9%), equipment and instrument management(7%), calculation of the dose of injection(2%) and the like.

• Science of Emotion and Sensibility
• /
• v.13 no.3
• /
• pp.581-596
• /
• 2010

The purposes of this study are to investigate and analyze the level of information and the state of digital divide of the disabled by surveying the demand for information and communication assistive devices, and to provide basic data for plans on the development and utilization of information and communication assistive devices. In order to understand the actual condition and the state of digital divide of persons with disabilities, the differences of possession and accessibility of information technology devices, usage ability, and utilization were analyzed according to the disability profile by using the T-test. The results show that there are significant differences (T=-2.510*) of possession and accessibility of information technology devices with respect to the disability profile, and that the disabled have lower possession and accessibility of devices than the non-disabled. Result of this study's demand forecast shows that about 28% of total respondents are currently using information and communication assistive devices, and a majority (67%) of them answered that the use of assistive devices lend great help to their lives. The proportion of those who have been supported by the government or related organizations with information and communication assistive devices were 36% of the total respondents, and those satisfied with the performance of the devices were 46% of the total responses. Meanwhile, only 36% of total users answered that the operation and use of functions of the devices was easy and convenient, responding that the difficulty of operating assistive devices was the greatest inconvenience. Moreover, the general requests of respondents in regards to the devices were stabilization of device performance, miniaturization of size, simplification of buttons, and reduction of weight.

• The Korean Journal of Air & Space Law and Policy
• /
• v.35 no.3
• /
• pp.3-37
• /
• 2020

The aircraft crew operating on international routes performs almost identical tasks as police officials in terms of dealing with the unlawful interference in the aircraft. This means that the liability question which is related to the law enforcement by the police officer may arise regarding the crew's performance of his or her duties. With regard to the carrier's liability due to the crew's unlawful action, there are distinctive characteristics from the liability due to police officers' unlawful action. In case of the claim for damages by the crew's unlawful action, the first question should be whether such action complies with the requirements under the Tokyo Convention 1963. If such action does not conform with the Tokyo Convention 1963, we should examine that claim under the State Compensation Act, the Montreal Convention 1999, and the Civil Act of Korea. The examination under the Tokyo Convention 1963 is not so different from the Korean Court's precedents. However, the court should consider the characteristics of the environment surrounding the crew. The action which is not indemnified under the Tokyo Convention 1963 should be examined under the tort laws. Because the aircraft crew is private persons entrusted with public duties under Korean Law, the State Compensation Act may apply. However, further studies regarding the harmonious interpretation with the Montreal Convention 1999 is needed. With regard to the carrier's liability, the Montreal Convention of 1999 should be applied to the crew's unlawful actions onboard. This is because the Montreal Convention of 1999 preempts the national law for the events that occurred during transportation, and there is no provision which excludes such unlawful actions from the scope of its application. On the other hand, the national law, such as the Civil Act of Korea, applies to unlawful actions taken after transportation. This is because the interpretation that infinitely expands the scope of the Montreal Convention 1999 should not be allowed. Given the foregoing, the standard of the claim for damages due to the crew's unlawful action varies depending on the place where the specific action was taken. As a result, the type of damage recoverable and the burden of proof also varies accordingly. Carriers and crew members must perform their duties with this in mind, but in particular, they should observe the proportionality, and when interpreting the law, it is necessary for the court or lawyer to consider the special characteristics of the work environment.

• Korean Security Journal
• /
• no.37
• /
• pp.325-354
• /
• 2013

The concept of national security and the fundamental system for crisis management have departed from traditional methods and the importance of a national critical infrastructure crisis management has been emphasized. A national critical infrastructure crisis means a situation where human resource, material and functional system that may have a material effect on the critical functions of the government, the vitality and integrity of society, national economy and the safety of the public becomes disabled due to causes such as terrorism or major disasters. Although North Korea had been subject to numerous rounds of negotiations and sanctions as it continually developed nuclear weapons since the 1960s, it has also showed off its nuclear armaments through successful nuclear testings and missile launches. As the development and threat of North Korea's weapons of mass destruction becomes more noticeable and the range of its risk expands, this study focuses on the potential for an absence of leadership for national crisis management where the country's leadership, which should serve the critical role and function of handling national crises, becomes completely destroyed by the unexpected initial attacks by North Korea. As a result, the purpose of this study is to propose safety measures for the country's leadership in preparation for North Korea's threat of nuclear weapons by examining the concept and degree of risk of weapons of mass destruction with a focus on nuclear weapons, analyzing the substance of the threat of North Korean nuclear weapons and evaluating such threat. In conclusion, first, to ensure the normal functioning of a national crisis management system in the event of a national crisis, we must seek safety measures that conform to the scope and succession order of the leadership of the national crisis management for an Enduring Constitutional Government (ECG) and the Continuity Of Operations (COOP). Second, in the event of a national ceremony, the gathering of the country's leadership all together in an open place should be avoided. In unavoidable circumstances, the next in rank that will act on behalf of the current leader should be designated and relevant safety measures should be taken. Third, during time of peace, in preparation for national crises, the scope of protection for the country's leadership should be prescribed and specific security and safety measures should be implemented. Fourth, the succession order for acting president in the case of the death of the president pursuant to Articles 71 and 26(1) of the National Government Organization Act should reconsidered to see whether it is a reasonable provision that takes into consideration a national crisis management that corresponds to the threat of North Korean nuclear weapons and weapons of mass destruction. Pursuant to the Basic Guidelines for National Crisis Management set out under Presidential Directive No. 229, the Korean government is currently operating a case-by-case "crisis management standard manual" and its sub-manuals and has also prepared the Presidential Security Service's security and safety measure regulations regarding the acting president. Therefore, the Korean government should actualize the above points in the case-by-case crisis management standard manual and security and safety measure regulations regarding the acting president to implement and legislate them.

• Journal of the Korean Electrochemical Society
• /
• v.23 no.4
• /
• pp.105-112
• /
• 2020

Transition metal oxide, which undergoes a conversion reaction in the negative electrode material for a lithium-ion batteries, has a high specific capacity, but still has several critical problems. In this study, manganese pyrophosphate (Mn₂P₂O₇), nickel pyrophosphate (Ni₂P₂O₇), and carbon composite materials with pyrophosphates as novel negative electrode materials instead of transition metal oxide, are synthesized through simple solid-state reaction. The initial reversible capacity of Mn₂P₂O₇ and Ni₂P₂O₇ are 333 and 340 mAh g^-1, and when the composite materials are composed with carbon, the reversible capacity increases to 433 and 387 mAh g^-1, respectively. The initial Coulombic efficiency is also improved by about 10%. The Mn₂P₂O₇ and carbon composite material has the highest initial capacity and efficiency, and has the best cycle performance. Mn₂P₂O₇ containing polyanion, has a lower specific capacity due to the large mass of polyanion compared to MnO (manganese oxide). However, since Mn₂P₂O₇ shows a voltage curve with a slope, the charging (lithiation) voltage increases from 0.51 to 0.57 V (vs. Li/Li⁺), and the discharge (delithiation) voltage decreases from 1.15 to 1.01 V (vs. Li/Li⁺). Therefore, the voltage efficiency of the cell is improved because the voltage difference between charging and discharging is greatly reduced from 0.64 to 0.44 V, and the operating voltage of the full cell increases because the negative electrode potential is lowered during the discharging process.

• Journal of the Korean Society of Food Culture
• /
• v.3 no.2
• /
• pp.187-195
• /
• 1988

In accordance with the rapidly growing number of street food service without a registration, a study was undertaken to determine the present state of food service by the covered wagon bar, through an investigation in Jamwondong, around the south gate market and Kangnam subway station, in Seoul, between July 25th and August 25th of 1987. The survey was comprised of three parts: 1) foodservice operation in covered wagon, 2) personal and food handling hygiene, 3) food behaviors of customers. A total of 54 covered wagon bars, consisting of 51.8% mobile bars and 48.2% non-mobile bars, operating in the above three locations, were investigated. Survey results show non-mobile covered wagon bars to be more popular among persons in their thrities and fourties than among teens or the elderly; also among males than females; among company employees and college students than others. Seventy five percent of the mobile covered wagon bars served snack type foods and others served wine and foods for wine, in contrast to hundred percent of the non-mobile covered wagon bars served wine and foods for wine. The survey found many problems of hygiene, in method of food purchasing, menu planning, food preparation, dish washing treatment of leftovers and water supply, as well as personal hygiene. However, customers prefer the casual and popular atmosphere at the counter of the covered wagon bar. Finally, the study emphasizes a need for better operation of covered wagon bar, improvement of food stuff handling and the way of food services and personal hygiene. A change of the registration system from the illegal operation are urgently needed for better quality food services of covered wagon bars.