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Improvement of Energy Density in Supercapacitor by Ion Doping Control for Energy Storage System (에너지 저장장치용 슈퍼커패시터 이온 도핑 제어를 통한 에너지 밀도 향상 연구)

  • Park, Byung-jun;Yoo, SeonMi;Yang, SeongEun;Han, SangChul;No, TaeMoo;Lee, Young Hee;Han, YoungHee
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.3
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    • pp.209-213
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    • 2019
  • Recently, demand for high energy density and long cycling stability of energy storage system has increased for application using with frequency regulation (F/R) in power grid. Supercapacitor have long lifetime and high charge and discharge rate, it is very adaptable to apply a frequency regulation in power grid. Supercapacitor can complement batteries to reduce the size and installation of batteries. Because their utilization in a system can potentially eliminate the need for short-term frequent replacement as required by batteries, hence, saving the resources invested in the upkeep of the whole system or extension of lifecycle of batteries in the long run of power grid. However, low energy density in supercapacitor is critical weakness to utilization for huge energy storage system of power grid. So, it is still far from being able to replace batteries and struggle in meeting the demand for a high energy density. But, today, LIC (Lithium Ion Capacitor) considered as an attractive structure to improve energy density much more than EDLC (Electric double layer capacitor) because LIC has high voltage range up to 3.8 V. But, many aspects of the electrochemical performance of LIC still need to be examined closely in order to apply for commercial use. In this study, in order to improve the capacitance of LIC related with energy density, we designed new method of pre-doping in anode electrode. The electrode in cathode were fabricated in dry room which has a relative humidity under 0.1% and constant electrode thickness over $100{\mu}m$ was manufactured for stable mechanical strength and anode doping. To minimize of contact resistance, fabricated electrode was conducted hot compression process from room temperature to $65^{\circ}C$. We designed various pre-doping method for LIC structure and analyzing the doping mechanism issues. Finally, we suggest new pre-doping method to improve the capacitance and electrochemical stability for LIC.

Improvement in Calculating Engineer Standard Wage Rate and Its Appropriate Level Computation (엔지니어링 노임단가 산출기준 개선방안과 적정 노임단가 추정)

  • Lee, Jae Yul;Lee, Hae Kyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.6
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    • pp.853-860
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    • 2022
  • The purpose of this study is to suggest an improvement plan for the calculation method of the engineer standard wage rate (ESWR) and to compute a reasonable ESWR. To this end, an adequacy review of theESWR calculation criteria was conducted along with an extensive engineering industry survey. The survey results were analyzed using an effective response sample of 748 companies out of 1,000 survey samples extracted by stratifying the 5,879 survey population. The main results were as follows. ①When calculating the engineering service fee, the prime contractor's engineer wage is suitable for the ESWR. The ESWR can be estimated by the formula 'average wage÷[1-proportion of subcontract orders×(1-subcontract rate)].' ② The field survey showed that the number of monthly working days was 20.35-20.54 days at 99 % confidence interval, which was significantly different from the current standard (22 days). In addition, as a result of a legal review of the ESWR criteria, it was found that the number of working days should be calculated in accordance with the Labor Standards Act after 2022. ③ Applying government guidelines, the time difference between the wage survey and the ESWR application can be corrected by the past ESWR increase rate for a specific period. ④ Using modeling based on the analysis above, the current ESWR was 13.5-14.5 % lower than the appropriate level. A lower ESWR was driven by the non-reflection of subcontract structure (4.1 %), overestimation of monthly work days (6.8-7.8 %), and application of past wage (2.6 %). The proposed model is expected to be widely used in policy making, as it can provide a useful framework for calculating the standard wage rate in similar industries as well as calculating appropriate engineering fees.

4D Printing Materials for Soft Robots (소프트 로봇용 4D 프린팅 소재)

  • Sunhee Lee
    • Fashion & Textile Research Journal
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    • v.24 no.6
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    • pp.667-685
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    • 2022
  • This paper aims to investigate 4D printing materials for soft robots. 4D printing is a targeted evolution of the 3D printed structure in shape, property, and functionality. It is capable of self-assembly, multi-functionality, and self-repair. In addition, it is time-dependent, printer-independent, and predictable. The shape-shifting behaviors considered in 4D printing include folding, bending, twisting, linear or nonlinear expansion/contraction, surface curling, and generating surface topographical features. The shapes can shift from 1D to 1D, 1D to 2D, 2D to 2D, 1D to 3D, 2D to 3D, and 3D to 3D. In the 4D printing auxetic structure, the kinetiX is a cellular-based material design composed of rigid plates and elastic hinges. In pneumatic auxetics based on the kirigami structure, an inverse optimization method for designing and fabricating morphs three-dimensional shapes out of patterns laid out flat. When 4D printing material is molded into a deformable 3D structure, it can be applied to the exoskeleton material of soft robots such as upper and lower limbs, fingers, hands, toes, and feet. Research on 4D printing materials for soft robots is essential in developing smart clothing for healthcare in the textile and fashion industry.

Lung Injury Indices Depending on Tumor Necrosis Factor-$\alpha$ Level and Novel 35 kDa Protein Synthesis in Lipopolysaccharide-Treated Rat (내독소처치 흰쥐에서 Tumor Necrosis Factor-$\alpha$치 상승에 따른 폐손상 악화 및 35 kDa 단백질 합성)

  • Choi, Young-Mee;Kim, Young-Kyoon;Kwon, Soon-Seog;Kim, Kwan-Hyoung;Moon, Hwa-Sik;Song, Jeong-Sup;Park, Sung-Hak
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.6
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    • pp.1236-1251
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    • 1998
  • Background : TNF-$\alpha$ appears to be a central mediator of the host response to sepsis. While TNF-$\alpha$ is mainly considered a proinflammatory cytokine, it can also act as a direct cytotoxic cytokine. However, there are not so many studies about the relationship bet ween TNF-$\alpha$ level and lung injury severity in ALI, particularly regarding the case of ALI caused by direct lung injury such as diffuse pulmonary infection. Recently, a natural defense mechanism, known as the stress response or the heat shock response, has been reported in cellular or tissue injury reaction. There are a number of reports examining the protective role of pre-induced heat stress proteins on subsequent LPS-induced TNF-$\alpha$ release from monocyte or macrophage and also on subsequent LPS-induced ALI in animals. However it is not well established whether the stress protein synthesis such as HSP can be induced from rat alveolar macrophages by in vitro or in vivo LPS stimulation. Methods : We measured the level of TNF-$\alpha$, the percentage of inflammatory cells in bronchoalveolar lavage fluid, protein synthesis in alveolar macrophages isolated from rats at 1, 2, 3, 4, 6, 12, and 24 hours after intratracheal LPS instillation. We performed histologic examination and also obtained histologic lung injury index score in lungs from other rats at 1, 2, 3, 4, 6, 12, 24 h after intratracheal LPS instillation. Isolated non-stimulated macrophages were incubated for 2 h with different concentration of LPS (0, 1, 10, 100 ng/ml, 1, or 10 ${\mu}g/ml$). Other non-stimulated macrophages were exposed at $43^{\circ}C$ for 15 min, then returned to at $37^{\circ}C$ in 5% CO2-95% for 1 hour, and then incubated for 2 h with LPS (0, 1, 10, 100ng/ml, 1, or 10 ${\mu}g/ml$). Results : TNF-$\alpha$ levels began to increase significantly at 1 h, reached a peak at 3 h (P<0.0001), began to decrease at 6 h, and returned to control level at 12 h after LPS instillation. The percentage of inflammatory cells (neutrophils and alveolar macrophages) began to change significantly at 2 h, reached a peak at 6 h, began to recover but still showed significant change at 12 h, and showed insignificant change at 24 h after LPS instillation compared with the normal control. After LPS instillation, the score of histologic lung injury index reached a maximum value at 6 h and remained steady for 24 hours. 35 kDa protein band was newly synthesized in alveolar macrophage from 1 hour on for 24 hours after LPS instillation. Inducible heat stress protein 72 was not found in any alveolar macrophages obtained from rats after LPS instillation. TNF-$\alpha$ levels in supernatants of LPS-stimulated macro phages were significantly higher than those of non-stimulated macrophages(p<0.05). Following LPS stimulation, TNF-$\alpha$ levels in supernatants were significantly lower after heat treatment than in those without heat treatment (p<0.05). The inducible heat stress protein 72 was not found at any concentrations of LPS stimulation. Whereas the 35 kDa protein band was exclusively found at dose of LPS of 10 ${\mu}g/ml$. Conclusion : TNF-$\alpha$ has a direct or indirect close relationship with lung injury severity in acute lung injury or acute respiratory distress syndrome. In vivo and in vitro LPS stimulation dose not induce heat stress protein 72 in alveolar macrophages. It is likely that 35 kDa protein, synthesized by alveolar macrophage after LPS instillation, does not have a defense role in acute lung injury.

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Studies on the Assumption of the Locations and Formational Characteristics in Yigye-gugok, Mt. Bukhansan (북한산 이계구곡(耳溪九曲)의 위치비정과 집경(集景) 특성)

  • Jung, Woo-Jin;Rho, Jae-Hyun;Lee, Hee-Young
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.3
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    • pp.41-66
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    • 2017
  • The purpose of this research is to empirically trace the junctures of Yigye-gugok managed by Gwan-am Hong Gyeong-mo, a grandson of Yigye Hong Yang-ho who originally designed Yigye-gugok, while reviewing the features of the forms and patterns of gugok. The results of the research are as follows. 1. Ui-dong was part of the domain of the capital during the Chosun dynasty, which also is located in the city of Seoul as a matter of administrative zone. Likewisely, Yigye-gugok is taken as a special meaning for it was one and only gugok. Starting with Mangyeong Waterfall as the $1^{st}$ gok, Yigye follows through the $2^{nd}$ gok of Jeokchwibyeong Rock, the $3^{rd}$ gok of Chanunbong Peak, the $4^{th}$ gok of Jinuigang Rock, the $5^{th}$ gok of Okkyeongdae Rock, the $6^{th}$ gok of Wolyeongdam Pond, the $7^{th}$ gok of Tagyeongam Rock, the $8^{th}$ gok of Myeongoktan Stream, and the $9^{th}$ gok of Jaeganjeong Pavilion. Of these, Mangyeong Waterfall, Chanunbong Peak, and Okkyeongdae Rock are distinct for their locations in as much as their features, while estimated locations for Jinuigang Rock, Wolyeongdam Pond, Myeongoktan Stream, and Jaeganjeong Pavilion were discovered. However, Jeokchwibyeong Rock and Tagyeongam Rock demonstrated multiple locations in close resemblance to documentary literatures within secretive proximity, whereas geography, scenery, and sighted objects were considered to evaluate the 1st estimated location. Through these endeavored, it was possible to identify the shipping routes and structures for the total distance of 2.1km running from the $1^{st}$ gok to the $9^{th}$ gok, which nears Gwanam's description of 5ri(里), or approximately 1.96km for gugok. 2. Set towards the end of the $18^{th}$ century, Yigye-gugok originated from a series of work shaping the space of Hong Yang-ho's tomb into a space for the family. Comparing Yigye-gugok to other gugoks, numerous differences are apparent from beyond the rather more general format such as adjoining the $8^{th}$ gok while paving through the lower directions from the upper directions of the water. This gives rises to the interpretation such that Yigye-gugok was positioned to separate the doman of the family from those of the other families in power, thereby taking over Ui-dong. Yet, the aspect of the possession of the space lends itself to the determination that the location positioned at the $8^{th}$ gok above Mangyeongpok Waterfall representing Wooyi-dong was a consequence of the centrifugal space creation efforts. 3. While writings and poetic works were manufactured in such large quantities in Yigye-gugok whose products of setters and managers seemed intended towards gugok-do and letters carved on the rocks among others, there is yet a tremendous lack of visual media in the same respect. 'Yigye-gugok Daejacheop' Specimens of Handwriting offers the traces of Gwanam's attempts to engrave gakja at the food of Yigye-gugok. This research was able to ascertain that 'Yigye-gugok Daejacheop' Specimens of Handwriting was a product of Hong Yang-ho's collections maintained under the auspices of the National Central Museum, which are renowned for Song Shi-yeol's penmanship.

Activities of Daily Living and Instrumental Activities of Daily Living of Elderlies in Chollabuk-Do Area (일부 전북지역 노인들의 일상생활동작능력과 수단적 일상생활동작능력)

  • Lee, Ki-Nam;Jeung, Jae-Yeal;Jahng, Doo-Sub;Lee, Sung-Kook
    • Journal of agricultural medicine and community health
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    • v.25 no.1
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    • pp.65-83
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    • 2000
  • To know the relationship of general characteristics with activities of daily living(ADL) and instrumental activities of daily living(IADL), we carried out the study on the elderies living in Chollabuk-Do area during 6 months, from June to December in 1999. Study subjects were 281, women and men were 195(69.6%) and 85(30.4%) respectively. Mean ages of women and men were 71.9 and 70.8 respectively. 81.1% elderies has disease and 18.9% were disease free. Disease prevalences of movement joint disease, others, circulatory disease, digestive disease, dental disease, respiratory disease were 50.1%, 25.0%, 10.5%, 9.4%, 8.5%, and 6.3% respectively. The percentages to the use of medical institution in recent were 40.0% for hospital, 16.8% for oriental hospital, 14.5% for public health center, 10.9% for drug store, 10.0% for others, and 7.8% for dental service. The percentages to the improvement of symptom after the use of medical institution were 62.3% for normal, 19.4% for improvement, and 18.2% for non-improvement. The percentages to the health situation were 37.1% for bad, 35.7% for good, and 27.1% for normal. Activities of daily living were 67.1% for 6 scores, 27.9% for 5 scores, 2.1% for 4 scores and ADL of women was lower than the men's. Instrumental activities of daily living were 50.4% for 5 scores, 19.3% for 3 scores, 12.1% for 4 scores and IADL of women was lower than the men's. Frequencies of disability in ADL were 28.9% for incontinence, 6.1% for bathing, 2.9% for meal, 2.5% for walking around house, 1.8% for toilet use, 1.4% for dressing and disability frequencies of women in 6 items of ADL were higher than the men's. The percentages of high, intermediate, low ADL in activities of daily living were 67.1%, 32.5%, 0.4% respectively and decrease of high ADL, increase of intermediate ADL were found with the increasing of age. Frequencies of disability in IADL were 42.9% for payment in and out, 31.8% for payment of written claim, 21.1% for shopping, 16.4% for preparation of meal, and 11.8% for use of bus. All items of women in IADL was higher than the men's but preparation of meal. The percentages of high, intermediate, low IADL in instrumental activities of daily living were 50.4%, 42.5%, 7.1% and decrease of high IADL, increase of intermediate IADL were found with the increasing of age. Mean of ADL with the general characteristics was 5.56 and 2 variables of level of education, health situation were statistically significant. Mean of IADL with the general characteristics was 3.76 and 8 variables of age, sex, level of education, occupation, presence of spouse, duty of living cost, health situation, category of ADL were statistically significant. With the result of stepwise regression, ADL was statistically related with religion, health situation and ADL was statistically related with level of education, living together with family, duty of living cost, health situation.

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