• Journal of the Korean Society of Radiology
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• v.81 no.3
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• pp.654-664
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• 2020

Purpose To determine the frequency of ossification of the transverse ligament of the atlas (OTLA) and to investigate the associated findings on cervical spine CT and plain radiography. Materials and Methods We reviewed 5201 CT scans of the cervical spine of 3975 consecutive patients over an 11-year period for the presence of OTLA and compared them with those of age- and sex-matched controls. The frequency and associated findings of OTLA were investigated and statistically correlated. Results The overall frequency of OTLA was 1.1% (45 of 3975 patients) and increased with age (p < 0.005). The frequency of OTLA in patients over 80 years was 12%. The space available for the spinal cord (SAC) was smaller in patients with OTLA (p < 0.005). Mineralization of the complex of the anterior atlantooccipital membrane and Barkow ligament, ossification of the ligamentum flavum, and kyphosis of the cervical spine positively correlated to the presence of OTLA (p < 0.005). Conclusion OTLA was associated with age, SAC narrowing, cervical kyphosis, and ossification of other cervical ligaments and may be associated with degenerative spondylosis, systemic hyperostotic status, or mechanical stress or instability.

• Journal of Industrial Convergence
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• v.22 no.7
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• pp.15-21
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• 2024

A hiking stick is generally one of the walking aids that allow hikers to walk while relying on their own bodies when walking. A rechargeable battery must be built into the hiking stick, which is an auxiliary device, in order to perform various functions. A separate power supply is required to charge the rechargeable battery. This study is about a self-generated power supply and develops a power generation device using a screw with higher power generation efficiency than the existing method. It is differentiated from the method suggested in this study by comparing and analyzing it with the existing power generation method, and identifying problems therewith. The screw-type power generation device generates power when the climbing stick comes into contact with the ground and when it is separated from the ground. The built-in power generation device does not require a separate power supply, and it can be used by attaching the role of a mobile phone auxiliary battery and a lighting lamp, and it has the effect of being able to find it through location tracking by embedding a GPS sensor, etc., and using lighting to keep the user safe in emergency situations such as distress. The existing generator with built-in mountain climbing stick is difficult to charge due to very weak current and low practicality, but the generator developed in this research could achieve high efficiency to obtain a sufficient current, so it is possible to charge a battery and practicality.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.54-60
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• 2010

We have researched the changes in nutrient content in each phase of fermentation in crops treated with liquefied pig fertilizer, and have determined the best method for applying livestock excrement to cultured crops. In the execution of this experiment, rice was cultivated to full maturity at a paddy field in Jeollabuk-Do Agriculture Research and Extension Services(Jeon-buk series) from 2007 to 2008. The rice plant nitrogen absorption quantity change, according to the growth stages of the cultivated rice, was 20.3% in the rice treated with the liquid pig manure and 22.2% the chemical fertilizer at highest congelation. The chemical fertilizer showed a higher absorption quantity than the liquid manure compost. The nitrogen density at highest congelation was 1.5% in the chemical fertilizer, and 1.8% in the pig manure liquid compost not a significant difference. The stem height at harvest time was 73.8 cm in the crops treated with the liquid pig manure compost. Those treated with the chemical fertilizer, yielded a height of 4.2 cm less than the crops treated with the liquid pig manure compost. The yield was 507 kg/10a in the liquid pig manure compost treated rice, compared with the chemical fertilizer, which showed a value of 1.2% lower. The protein content was 6.3% in the rice treated with the chemical fertilizer, but 6.4% in the rice treated with the liquid pig manure compost. This is not a significant difference. However, the lodging rice plant treated with the chemical fertilizer control showed a protein content of 6.8%, which was even higher than the normal rice. The head rice ratio in the brown rice and the polished rice ended up to be lower in the crop treated with the liquid pig manure than that treated with the chemical fertilizer, Quality, the palatability value, was similar in both groups. The above result indicate that, the effect of liquid pig manure compost corresponds to the effect of chemical fertilizer, when each are scattered uniformly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.203-209
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• 2009

Yield monitoring is one of a precision agriculture technology that is used most widely. It is spatial variability analysis of yield information that should be attained with yield monitoring system development. This experiment was conducted to evaluate spatial variability of yield and grain moisture content in rice paddy field, and their relationships to rice productivity. It is necessary to minimize sampling interval for accurate yield map making or to control cutting width of rice combine. Considering small rice plots such as $0.2{\sim}0.4$ ha, optimum size of sampling plot was below 15 m more than 5 m in with and length. In variable rate treatment field, average yield was similar, but yield variation was reduced than conventional field. Gap of yield by another plot in same field was bigger than half of average yield than yield variation was significantly big. Therefore yield measuring flow sensor must be able to measure at least 300 kg/10a more than 1000 kg/10a. Variation of moisture content in same field was not big and spatial dependance did not appear greatly. But, variation between different field is appeared difference according to weather circumstance before harvesting. Change of spatial dependence of yield was not big, because of field variation of moisture content is not big.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.145-152
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• 2016

The objective of this study was to evaluate the mechanical quality of cultivars that could potentially be used to processed cooked rice. Proximate composition, amylose content, cooking quality, and the Toyo value, were higher in Jungsaenggold than in the other cultivars. The results showed that the crude protein contents of the rice cultivars were between 4.60 and 6.59%. The amylose content was the highest in the Haedam cultivar (21.36%), but was the lowest in the Jungsaenggold cultivar (17.11%). Cooking quality was the highest in the Haiami and Jungsaenggold cultivar. Texture analyzer test showed that Ilpum had the lowest hardness and highest stickiness. Significant differences in the palatability characteristics (Toyo results for glossiness quality) of the rice flour were recorded using a Toyo Meter Analyzer. Ilpum, Samkwang, Haiami and Jungsaenggold had low amylose contents and the highest Toyo values. Thus, the results of this study suggested that Jungsaenggold can be effectively used to produce processed cooked rice.

• Journal of Intelligence and Information Systems
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• v.28 no.3
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• pp.259-278
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• 2022

With the spread of Artificial Intelligence (AI), various AI-based services are expanding in the financial sector such as service recommendation, automated customer response, fraud detection system(FDS), credit scoring services, etc. At the same time, problems related to reliability and unexpected social controversy are also occurring due to the nature of data-based machine learning. The need Based on this background, this study aimed to contribute to improving trust in AI-based financial services by proposing a checklist to secure fairness in AI-based credit scoring services which directly affects consumers' financial life. Among the key elements of trustworthy AI like transparency, safety, accountability, and fairness, fairness was selected as the subject of the study so that everyone could enjoy the benefits of automated algorithms from the perspective of inclusive finance without social discrimination. We divided the entire fairness related operation process into three areas like data, algorithms, and user areas through literature research. For each area, we constructed four detailed considerations for evaluation resulting in 12 checklists. The relative importance and priority of the categories were evaluated through the analytic hierarchy process (AHP). We use three different groups: financial field workers, artificial intelligence field workers, and general users which represent entire financial stakeholders. According to the importance of each stakeholder, three groups were classified and analyzed, and from a practical perspective, specific checks such as feasibility verification for using learning data and non-financial information and monitoring new inflow data were identified. Moreover, financial consumers in general were found to be highly considerate of the accuracy of result analysis and bias checks. We expect this result could contribute to the design and operation of fair AI-based financial services.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.877-887
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• 1996

The ideal membranes for membrane-covered oxygen probes system should be selectively permeable for oxygen and chemically inert, and have good mechanical strength. Polysulfone(PSf) was selected to develop the membrane for membrane-covered oxygen electrodes system. PSf membranes have properties such as good reproducibility, good mechanical strength, chemical inertness, and high heat resistance. PSf membranes were cast from polymer solution on the glass plate at constant temperature, and casting solvents used were tetrahydrofuran(THF), methylene chloride, and N-methyl-2-pyrrolidone(NMP). Tricresyl phosphate(TCP) as plasicizer was added to PSf to increase the softness of membrane. The permeation characteristics were observed for pure oxygen and nitrogen through pure PSf membranes by variable volume method and membrane-covered electrode system. The permeability coefficients of oxygen and nitrogen measured by variable volume method were slightly decreased with increasing of upstream pressure. The permeation properties of PSf membrane using methylene choride as casting solvent were not affected by the PSf amount of polymer solution. The permeability coefficients of oxygen and nitrogen for PSf membrane containing TCP were very slightly lower than those for pure PSf membrane, but ideal separation factors were slightly higher. The flexibility of PSf membrane containing 2wt% TCP was better than that of pure PSf membrane. It was expected that this increase in flexibility would solve the difficulty of fixing the membrane to the cathode. The membrane-covered oxygen probes system was composed of anode, cathode and electrolyte. The type of the anode was Ag/AgCl half-cell, that of cathode was Ag, and the electrolyte was 4N KCl solution. The result of sampled current voltametry for PSf membrane showed the plateu region at -0.3V~-1.0V. The correlation coefficient of oxygen partial pressure versus current for PSf membrane was relatively high, 0.99949. It was concluded that PSf membrane was the good candidate for the membrane-covered oxygen probes system.

• Journal of Intelligence and Information Systems
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• v.17 no.3
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• pp.187-201
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• 2011

KOSPI200 index is the Korean stock price index consisting of actively traded 200 stocks in the Korean stock market. Its base value of 100 was set on January 3, 1990. The Korea Exchange (KRX) developed derivatives markets on the KOSPI200 index. KOSPI200 index futures market, introduced in 1996, has become one of the most actively traded indexes markets in the world. Traders can make profit by entering a long position on the KOSPI200 index futures contract if the KOSPI200 index will rise in the future. Likewise, they can make profit by entering a short position if the KOSPI200 index will decline in the future. Basically, KOSPI200 index futures trading is a short-term zero-sum game and therefore most futures traders are using technical indicators. Advanced traders make stable profits by using system trading technique, also known as algorithm trading. Algorithm trading uses computer programs for receiving real-time stock market data, analyzing stock price movements with various technical indicators and automatically entering trading orders such as timing, price or quantity of the order without any human intervention. Recent studies have shown the usefulness of artificial intelligent systems in forecasting stock prices or investment risk. KOSPI200 index data is numerical time-series data which is a sequence of data points measured at successive uniform time intervals such as minute, day, week or month. KOSPI200 index futures traders use technical analysis to find out some patterns on the time-series chart. Although there are many technical indicators, their results indicate the market states among bull, bear and flat. Most strategies based on technical analysis are divided into trend following strategy and non-trend following strategy. Both strategies decide the market states based on the patterns of the KOSPI200 index time-series data. This goes well with Markov model (MM). Everybody knows that the next price is upper or lower than the last price or similar to the last price, and knows that the next price is influenced by the last price. However, nobody knows the exact status of the next price whether it goes up or down or flat. So, hidden Markov model (HMM) is better fitted than MM. HMM is divided into discrete HMM (DHMM) and continuous HMM (CHMM). The only difference between DHMM and CHMM is in their representation of state probabilities. DHMM uses discrete probability density function and CHMM uses continuous probability density function such as Gaussian Mixture Model. KOSPI200 index values are real number and these follow a continuous probability density function, so CHMM is proper than DHMM for the KOSPI200 index. In this paper, we present an artificial intelligent trading system based on CHMM for the KOSPI200 index futures system traders. Traders have experienced on technical trading for the KOSPI200 index futures market ever since the introduction of the KOSPI200 index futures market. They have applied many strategies to make profit in trading the KOSPI200 index futures. Some strategies are based on technical indicators such as moving averages or stochastics, and others are based on candlestick patterns such as three outside up, three outside down, harami or doji star. We show a trading system of moving average cross strategy based on CHMM, and we compare it to a traditional algorithmic trading system. We set the parameter values of moving averages at common values used by market practitioners. Empirical results are presented to compare the simulation performance with the traditional algorithmic trading system using long-term daily KOSPI200 index data of more than 20 years. Our suggested trading system shows higher trading performance than naive system trading.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.670-676
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• 1997

The structural failure of the glutaraldehyde-treated xenograft valves has been the primary concern about the limited durability as predicted from the begimling of clinical use, and long-term follow-up has shown a significant incidence of primary tissue failure(PTF) from both biological and mechanical reasons. Twenty-seven patients with the low-profile lonescu-Shiley valves explanted from mitral position for PTF(Group III) were studied on the patient characteristics and valve pathology, and the results were compared with the matched observations of the Haycock(Group I) and of the standard-profile lonesiu-Shiley valves(Group II). Patients were aged 16 to 56 years(mean, 38.0$\pm$ 11.0 years), and the size of the failed mitral bioprosthesis was 30.8$\pm$ 1.3 mm. The hemodynamic consequences were stenosis in 29.6%, insufficiency in 44.4%, mixed steno-insufficiency in 14.8%, together with normal function for the rest of patients of prophylactic re-replacement. Pathology revealed calcification with or without tissue damage in 63.0% and tissue damage with or without calcification in 58.l%, in contrast with the observations of predominant tissue damage(76.8%) over calcification in Group I and of calcification(76.1%) over tissue damage in group II. Although dystrophic calcification has long and repeatedly dealt with patient's young age as a determinant of valve durability, such a characteristic evidence was not reached even in patients with calcified valves. Moreover, the prolonged explantation p riods from the studied on the previous report suggested strongly yet possibly evolving destructive processes among the valves in the remaining patients, and awaits further follow-up. In conclusion, PTF of the xenograft valves seems to result from more complicated biologic and metabolic reasons as well as more complex mecharical factors than the reported, and newer generation prostheses, with tissue preservation with glutaraldehyde, do not likely to provide decisive improvement in the occurrence of structural failurebioprostheses is generally limited to the highly aged.

• Journal of agricultural medicine and community health
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• v.27 no.1
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• pp.115-123
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• 2002

Objective: The aim of this study was to evaluate the patterns of helicopter emergency medical services (HEMS) in Ullung Island. Methods : The authors reviewed the records from emergency room diaries and the lists of helicopter transfers in the Ullung Public Health Medical Center over the 5-year period from Jan 1, 1997 to Dec 31, 2001. Results : One hundred thirteen cases were transferred by helicopters in 88 flights. According to year, the number of flights was 13(14.8%) and the number of cases was 15(13.3%) in 1997; 17(19.3%) and 21(18.6%) in 1998; 18(20.5%) and 20(17.7%) in 1999; 17(19.3%) and 20(17.7%) in 2000; and 23(26.1%) and 37(32.7%) in 2001. According to the kind of helicopter, the number of flights was 46(52.3%) and the number of cases was 60(53.1%) by Maritime police; and 19(21.6%) and 28(25.1%) by 119 rescue. According to time zone, there were no night flights. According to sex and age, there were 75 male cases(66.4%) and 28 cases(28.3%) of patients aged sixty years and over. The number of flights was 11(12.5%) and the number of cases was 15(13.3%) in November; 10 flights(11.4%) and 14 cases(12.4%) in March; and 7 cases(8.0%) in each of September, October and April. The most common season of helicopter transfer cases was autumn. According to transfer area, there were 48 cases (42.5%) in Pohang city, Gyeonsangbukdo; 35(31.0%) in Gangnung city, Gangwondo; and 17(15.0%) in Daegu metropolitan city. According to condition, there were 27 cases(23.9%) of cerebro-vascular accident, 13(11.5%) of fracture and 11(9.7%) of head injury. According to admission department, there were 42 cases(37.2%) in Neurosurgery, 21(18.6%) in Internal Medicine and 13(11.5%) in Orthopedic Surgery. According tothe Korea Standard Classification of Disease(3-KSCD), circulatory systemic disease(IX) and injury, intoxication and others (XIX) were the two most frequent categories with 34 cases(30.1%) each, followed by digestive system disease (XI) with 23 cases(20.4%). Conclusions : HEMS in Ullung Island leave much to be desired. Helicopters cannot make a night flight and are not equipped with medical facilities. HEMS in islands such as Ullung Island are essential. We hope that night flights, equipment-monitoring systems for emergency patients in the helicopters, and a law related to HEMS in the island will all be established.