• Korean Journal of Materials Research
• /
• v.22 no.7
• /
• pp.346-351
• /
• 2012

$Li_{1+x}Al_xTi_{2-x}(PO_4)_3$(LATP) is a promising solid electrolyte for all-solid-state Li ion batteries. In this study, LATP is prepared through a sol-gel method using relatively the inexpensive reagents $TiCl_4$. The thermal behavior, structural characteristics, fractured surface morphology, ion conductivity, and activation energy of the LATP sintered bodies are investigated by TG-DTA, X-ray diffraction, FE-SEM, and by an impedance method. A gelation powder was calcined at $500^{\circ}C$. A single crystalline phase of the $LiTi_2(PO_4)_3$(LTP) system was obtained at a calcination temperature above $650^{\circ}C$. The obtained powder was pelletized and sintered at $900^{\circ}C$ and $1000^{\circ}C$. The LTP sintered at $900{\sim}1000^{\circ}C$ for 6 h had a relatively low apparent density of 75~80%. The LATP(x = 0.3) pellet sintered at $900^{\circ}C$ for 6 h was denser than those sintered under other conditions and showed the highest ion conductivity of $4.50{\times}10^{-5}$ S/cm at room temperature. However, the ion conductivity of LATP (x = 0.3) sintered at $1000^{\circ}C$ decreased to $1.81{\times}10^{-5}$ S/cm, leading to Li volatilization and abnormal grain growth. For LATP sintered at $900^{\circ}C$ for 6 h, x = 0.3 shows the lowest activation energy of 0.42 eV in the temperature range of room temperature to $300^{\circ}C$.

• Journal of Preventive Medicine and Public Health
• /
• v.39 no.4
• /
• pp.353-358
• /
• 2006

Objectives: An increase in the serum gamma-glutamyltransferase (GGT) concentration has been regarded as a marker of alcohol drinking or liver disease. Some reports, however, have suggested that the serum GGT may be a sensitive and early biomarker for the development of prediabetes and diabetes. In this study we investigated whether serum GGT is a reliable predictor of the incident impaired fasting glucose (IFG), including diabetes. Methods: We performed a prospective study for two years (2002-2004). We analyzed the periodic health examination data from a total of 4,711 men. The examinations were done in the years 2002 and 2004. The analyzed data included a self-questionnaire, a physical examination and the laboratory results. Both IFG and diabetes were defined as a serum fasting glucose concentration of more than 100 mg/dL and 126 mg/dL, respectively. Results: A total of 738 cases (15.7%) of incident IFG and 13 cases (0.3%) of diabetes occurred. The mean serum GGT concentrations were quite different between the normal (38.0 IU) and incident IFG groups (50.3 IU), and the incident diabetes group (66.0 IU) (p<0.001). After multivariable adjustment, the relative risks for incident IFG or diabetes across the baseline GGT categories (<10th, 10th-20th, 30th-40th, 50th-60th, 70th-80th and >90th percentile) were 1.0, 1.172 (0.769-1.785), 1.107 (0.725-1.689), 1.444 (0.934-2.232), 2.061 (1.401-3.031) and 2.545 (1.784-3.631) (p-value for trend: <0.001). The risks significantly increased with increasing levels of GGT for 2 years; when comparing the increased groups (<10%, 10-20%, >20%) versus the decreased over 20% group of GGT, the risks for IFG or diabetes were 1.334 (1.002-1.776), 1.613 (1.183-2.199) and 1.399 (1.092-1.794). Conclusions: Our findings suggest that serum GGT concentrations within its normal range may be an early predictor of the development of IFG and diabetes. As serum GGT is a relatively inexpensive test and a reliable marker, it might have important implications in public health promotion.

• Journal of Nutrition and Health
• /
• v.9 no.3
• /
• pp.35-45
• /
• 1976

To investigate the food choices and Dietary Preferences of College Women the number of dishes sold and the sales of the midmeal at the Student Cafeteria, Ewha Womans University were recorded for the fiscal year of 1974; and the observations were made on two consecutive days (June 3rd and 4th, 1974)on what a person has chosen which and how many dishes. The relationship between the number of the consecutive days and the number of foods chosen were treated as Chi square analysis. The results of the food choices and dietary preferences of College Women were as follows: 1. Breads and rice cakes, vegetable dishes, milk and milk products, rice dishes, soups, meat, fish, poultry and eggs, Kimchis and one dish meal were chosen highly; and beverages, stews, and soybeans and soybean products were chosen negligibly. 2. One dish meals, vegetable dishes, meat, fish, poultry and eggs, milk and milk products showed the highest sales volume during the year; rice dishes, breads and rice cakes were the second highest in sales amount; fried foods, snacks and Kimchis showed the range of $3{\sim}6%$ of the total sales; and the beverages, stews, soybean and soybean products were the lowest in sales amount. 3. Seasonal differences were noticed on some dishes. Breads add rice cakes, milk and milk products showed the high selections from March to November and the low, during December to February. Stews, Kimchis, beverages were kept low except sudden rise on February. One dish meal and rice dishes showed almost same level during the year but on February the slight increase were noticed; even level were kept on meat group except the increase to $13{\sim}16%$ on July and December. Fried foods were kept on similar level during the year except the increase on June. Snacks and fruits showed low selections on March, April, November and December and higher at summer. Vegetables, soups, soybean and soybean products showed no different fluctuations in selections during the year. 4. Rolls, salads, milk, hamburgers, fried vegetables, rice with mired vegetables(Bi-bim-bab), and Nang-myun were the single dishes chosen most frequently. 5. There is significant relationship at 0.05 level between the consecutive days and the number of foods chosen. It is concluded that about 50% of the population has taken one item of dishes. The popular combinations were one dish meal and soup or Kimchi; noodles and salads or fried vegetables. It is suggested to set up choice menus with the daily variations, cyclical variations and with the invariable ones; and to recommend one dish meal, breads, partial meals for school lunch; and to study to improve one dish meal, vegetable dishes and fried foods, which are new and inexpensive products. It is also suggested that the feeding of the college students should have to lead the people to the goal that the nutrition education is desired.

• Current Research on Agriculture and Life Sciences
• /
• v.2
• /
• pp.29-33
• /
• 1984

From June 28th to July 17th in 1985, this study was performed to obtain the information of the fresh corn forage production through the spraying hydrophonics in summer. The experiments were conducted in vinyl house on Kyungpook University's Experimental Station. The results obtained were as follows: It was suggested that the treatment of soaking for 24 hrs and followed by the pretreatment for 48 hrs was better than other treatments. Seed cost for the production of 1 kg fresh forage was the most inexpensive at the seeding rate of 450 g per $30{\times}60cm$ tray than other seeding rates. Application of 1000 times diluted Hyponex solution (1000X Hyponex) or 300 times diluted Yogen solution (300X Yogen) one time per day resulted in the heavier fresh weight than the other treatments. Treatments of 300X Yogen and 500X Yogen gave the better fresh weight in one application per two days and per three days, respectively. But, this method was not useful in summer because the lowest seed cost for the production 1kg fresh forage was 73Won, and collection of the fresh forage from the mountain range was easy.

• Resources Recycling
• /
• v.29 no.5
• /
• pp.15-27
• /
• 2020

Microplastics are recognized as critical and serious environmental problem in worldwide. Plastics are inexpensive, lightweight, excellent in processability, and various in material-specific properties. Along industrial development, the production and disposal amount of plastics are also rapidly increasing. In particular, abundant plastic wastes are eventually disposed into marine environment with harmful impacts on the ecosystem. Therefore, lots of relevant studies were recently progressed in various fields. However, many studies are being just conducted due to its difficulty in applying a general treatment method for those small particle sizes and their various characteristics. In the meantime, lots of researches are being conducted on applying methods using physical properties such as specific gravity, magnetic, and electrostatic separation, which are beneficiation processes of minerals. However, since it is still in the laboratory stage, the development of larger scale separation technology for efficient treatment is urgent.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.05a
• /
• pp.733-736
• /
• 2009

Power Line Communication(PLC) is need not additional communication line. So establishment expense is inexpensive and application is simple. Therefore, lower part network of various application field is possible. However, there are high subordinate interference and noise problem on limited transmission data and communication interference element. Wireless Sensor Network(WSN) is need not infrastructure, Self-regulating network architecture of sensor nodes is possible. So at short time, network construction is available. But, power consumption is increased by active sensing for QoS elevation and unnecessary information transmission, low electric power design and necessity of improve protocol are refered to life shortening problem and is studied. In this paper, supplement problem of power line communication and wireless sensor network mutually and because advantage becomes linkage integration control system using synergy effect of two technologies as more restriction be and tries to approach structurally control network that is improved for smooth network environment construction. Honeywell's hybrid sensor network does comparative analysis(benchmarking). Confirm performance elevation proposing teaming of power line communication and wireless sensor network. Through simulation, service delay decreases and confirms that performance elevation.

• Journal of Korea Port Economic Association
• /
• v.25 no.3
• /
• pp.165-182
• /
• 2009

The purpose of this paper is to study on the third party logistics service enforcement of inland container depot at Pusan area. The main results of this paper are as follows: First, the inland container depot related to location selecting factor researches analyzed and korean TPL market reviewed. Second, the TPL service function reinforcement method and investments are mentioned. In detail the 9 factors are as follows: competitive high position and improvements of harbor back complex, ICD goods enterprise investment strategies, the harbor back which is inexpensive only the rent, taxes benefit and incentive, site security and base facility expansion, the goods service provision which is flexible, connection plan construction of goods enterprise, the incentive strategic establishment which is discriminated, the marketing activity which is long-term. and lastly the ICD and TPL Policy are needed that government and logistic enterprise's cooperation gains competitive advantage.

• Korean Journal of Optics and Photonics
• /
• v.28 no.5
• /
• pp.213-220
• /
• 2017

This paper proposes how to fabricate an educational Mach-Zehnder interferometer that is easy to align and inexpensive, using 3D printers and semiconductor lasers. The interferometer consists of a body $165mm{\times}120mm{\times}57mm$ in size, mirror mounts, a laser holder, beam splitters, and so on. The laser path is adjusted by 4 mirror mounts, each comprised of rubber bands, small metal wires, and a screw. The interference fringe is enlarged by the lens at the final stage. The refractive index of a slide glass was measured by counting the number of moving interference fringes while the slide glass, inserted into one of the two interferometer arms, is rotating. The formula for the refractive index as a function of the optical-path difference and rotation angle was obtained, and used to calculate the refractive index of glass from the interferometer experiment. The use of a rotating glass in one arm of the interferometer nullifies the need for a precision stage, which despite its high cost is often required to observe the moving interference fringe in the classroom. Therefore, the 3D-printed Mach-Zehnder interferometer proposed in this paper can be very useful for education, because of its affordability and performance. It enables students to perform both qualitative and quantitative studies using a 3D-printed interferometer, such as measuring the refractive index of a glass sample, and the wavelength of light.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.42
• /
• pp.32.1-32.4
• /
• 2020

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

• Journal of Adhesion and Interface
• /
• v.22 no.1
• /
• pp.1-7
• /
• 2021

The importance of high capacity energy storage devices has recently emerged for stable power supply through renewable energy generation. From this point of view, the Na-air battery (NAB), which is a next-generation secondary battery, is receiving huge attention because it can realize a high capacity through abundant and inexpensive raw materials. In this study, activated carbon-based catalysts for hybrid type Na-air batteries were prepared and their characteristics were compared and analysed. In particular, from the viewpoint of resource recycling, activated carbon (Orange-C) was prepared using discarded orange peel, and performance was compared with Vulcan carbon, which is widely used. In addition, a Pt/C catalyst (homemade-Pt/C, HM-Pt/C) was synthesized using a modified polyol method to check whether the prepared activated carbon can be used as a supported catalyst, and a commercial Pt/C catalyst (Commercial Pt/C) and electrochemical performance were compared. The prepared Orange-C exhibited a typical H3 type BET isotherm, which is evidence that micropore and mesopore exist. In addition, in the case of HM-Pt/C, it was confirmed through TEM analysis that Pt particles were evenly distributed on the activated carbon supported catalyst. In particular, the HM-Pt/C-based NAB showed the smallest voltage gap (0.224V) and good voltage efficiency (92.34%) in the 1st galvanostatic charge-discharge test. In addition, the cycle performance test conducted for 20 cycles showed the most stable performance.