• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.1
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• pp.107-114
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• 2021

By analyzing the voice communication performance of the existing tactical FM radios, the performance target of the newly developing TICN combat network radio system VHF band tactical voice communication waveform was derived. In addition, a vocoder and modulation method that can satisfy the performance target and additional requirements are presented, and the expected voice communication quality is analyzed.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.341-346
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• 2001

This paper presents a concept design of detail design software for high speed catenary system. In this software, M.D.(mounting diagram) can be peformed and parts D/B can be also managed. french one, used in Kyung-bu high-speed line, is not good at user's interface, and the source code is not opened. So, it is impossible to use it in the different environment and catenary system. Through this program, automation of detail design and user's convenience can be derived.

• Clinical and Experimental Pediatrics
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• v.54 no.2
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• pp.51-54
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• 2011

Vitamin D is present in two forms, ergocalciferol (vitamin $D_2$) produced by plants and cholecalciferol (vitamin $D_3$) produced by animal tissues or by the action of ultraviolet light on 7-dehydrocholesterol in human skin. Both forms of vitamin D are biologically inactive pro-hormones that must undergo sequential hydroxylations in the liver and the kidney before they can bind to and activate the vitamin D receptor. The hormonally active form of vitamin D, 1,25-dihydroxyvitamin D3 $[1,25(OH)_2D]$, plays an essential role in calcium and phosphate metabolism, bone growth, and cellular differentiation. Renal synthesis of $1,25(OH)_2D$ from its endogenous precursor, 25-hydroxyvitamin D (25OHD), is the rate-limiting and is catalyzed by the $1{\alpha}$-hydroxylase. Vitamin D dependent rickets type I (VDDR-I), also referred to as vitamin D $1{\alpha}$-hydroxylase deficiency or pseudovitamin D deficiency rickets, is an autosomal recessive disorder characterized clinically by hypotonia, muscle weakness, growth failure, hypocalcemic seizures in early infancy, and radiographic findings of rickets. Characteristic laboratory features are hypocalcemia, increased serum concentrations of parathyroid hormone (PTH), and low or undetectable serum concentrations of $1,25(OH)_2D$ despite normal or increased concentrations of 25OHD. Recent advances have showed in the cloning of the human $1{\alpha}$-hydroxylase and revealed mutations in its gene that cause VDDR-I. This review presents the biology of vitamin D, and $1{\alpha}$-hydroxylase mutations with clinical findings.

• International Journal of Stem Cells
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• v.17 no.1
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• pp.38-50
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• 2024

Induced pluripotent stem cell (iPSC) technology has revolutionized various fields, including stem cell research, disease modeling, and regenerative medicine. The evolution of iPSC-based models has transitioned from conventional two-dimensional systems to more physiologically relevant three-dimensional (3D) models such as spheroids and organoids. Nonetheless, there still remain challenges including limitations in creating complex 3D tissue geometry and structures, the emergence of necrotic core in existing 3D models, and limited scalability and reproducibility. 3D bioprinting has emerged as a revolutionary technology that can facilitate the development of complex 3D tissues and organs with high scalability and reproducibility. This innovative approach has the potential to effectively bridge the gap between conventional iPSC models and complex 3D tissues in vivo. This review focuses on current trends and advancements in the bioprinting of iPSCs. Specifically, it covers the fundamental concepts and techniques of bioprinting and bioink design, reviews recent progress in iPSC bioprinting research with a specific focus on bioprinting undifferentiated iPSCs, and concludes by discussing existing limitations and future prospects.

• Journal of the Optical Society of Korea
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• v.13 no.2
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• pp.251-255
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• 2009

In the non-contact 3-dimensional (3D) shape measurements, the fringe pattern projection method based on the phase-shifting technique has been considered very effective for its high speed and accuracy. The digital fringe projector in particular has great flexibility in generating fringe patterns since the patterns can be controlled easily by the computer program. In this work, we have developed a high-speed digital laser grating projection system using a laser diode and a polygon mirror, and evaluated its performance. It has been demonstrated that all the optical measurements required to find out the profile of a 3D object could be carried out within 31 ms, which confirmed the validity of our 3D measurement system. The result implies the more important fact that the speed in 3D measurement can be enhanced remarkably since, in our novel system, there is no device like a LCD or DMD whose response time limits the measurement speed.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.43-48
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• 2012

This paper presents an iterative single-frequency continuous-wave signal-based I/Q regeneration method for improving image-rejection performance of multi-port junction-based direct receivers (MPDRs). This paper analyzes I/Q regeneration in MPDRs as I/Q mismatch compensation for direct conversion receivers. Based on the analysis, this paper evaluates the accuracy of I/Q regeneration in terms of the image-rejection ratio (IRR). The proposed method improves the IRR performance more than 20 dB compared to existing I/Q regeneration methods. Simulation results show that MPDRs using the proposed method can achieve an IRR of more than 70 dB, and that the bit error rate performances are almost the same as those of conventional coherent demodulators, even in fading channels.

• Journal of Korean society of Dental Hygiene
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• v.10 no.2
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• pp.311-322
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• 2010

Objectives : Since the program about sodium lauryl sulfate that might cause oral dryness and taste change including oral tissue allergy was on the air, the ingredients of D.I.Y dentifrices without sodium lauryl sulfate have been sold in online shopping mall and ordinary people can make the dentifrices easily. But there have not been any reports about the effect of dental plaque removal and preference about D.I.Y dentifrices. Therefore, this study was designed as a pilot study which aimed to investigate the effect of dental plaque removal and prefernece about D.I.Y dentifrices. Methods : 6 subjects were collected to test the effect of dental plaque removal with D.I.Y dentifrices with written consent. They didn't brushed the teeth during 12 hours until the check-up time on the next day. The O'leary index was calculated in baseline, 1 minute, 2 minute, 3 minute after brusing with D.I.Y dentifrices and market dentifrices. The preference about D.I.Y dentifrices through self-administered questionnaire was surveyed in 51 subjects after using D.I.Y dentifrices. Results : 1. The market dentifrices could remove larger amount of dental plaque than D.I.Y dentifrices, but, it wasn't significant. 2. In feeling refreshment, the market dentifrices had more positive answers significantly. 3. In feeling taste change, the market dentifries had more duration of taste change significantly. 4. In feeling oral dryness, the market dentifrices had more duration of oral dryness after toothbrushing. but, it wasn't significant. 5. As a result about reviewing the dental journals about ingredients of D.I.Y dentirices, green tea, sodium carbonate, bamboo salt, propolis had each evidence. But, We could not find out the evidences of calculus adhesion by corn starch, preservative by napri, disinfectant of peppermint. Conclusions : Although we cannot find the difference of the effect of dental plaque removal between D.I.Y dentifrices and market dentifrices, and D.I.Y dentifrices have the merits of decrease of oral dryness and taste change, it was suggested to have another test about stability and safety of D.I.Y dentifrices for safety of the user of D.I.Y dentifrices.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.3
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• pp.265-273
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• 2024

This study aims to explore possible effect of RNA polymerase I subunit D (POLR1D) on proliferation and angiogenesis ability of colorectal cancer (CRC) cells and mechanism herein. The correlation of POLR1D and Yin Yang 1 (YY1) expressions with prognosis of CRC patients in TCGA database was analyzed. Quantitative realtime polymerase chain reaction (qRT-PCR) and Western blot were applied to detect expression levels of POLR1D and YY1 in CRC cell lines and CRC tissues. SW480 and HT-29 cells were transfected with si-POLR1D or pcDNA3.1-POLR1D to achieve POLR1D suppression or overexpression before cell migration, angiogenesis of human umbilical vein endothelial cells were assessed. Western blot was used to detect expressions of p38 MAPK signal pathway related proteins and interaction of YY1 with POLR1D was confirmed by dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). TCGA data showed that both POLR1D and YY1 expressions were up-regulated in CRC patients. High expression of POLR1D was associated with poor prognosis of CRC patients. The results showed that POLR1D and YY1 were highly expressed in CRC cell lines. Inhibition or overexpression of POLR1D can respectively suppress or enhance proliferation and angiogenesis of CRC cells. YY1 inhibition can suppress CRC progression and deactivate p38 MAPK signal pathway, which can be counteracted by POLR1D overexpression. JASPAR predicted YY1 can bind with POLR1D promoter, which was confirmed by dual luciferase reporter gene assay and ChIP. YY1 transcription can up-regulate POLR1D expression to activate p38 MAPK signal pathway, thus promoting proliferation and angiogenesis ability of CRC cells.

• Journal of the Korea Computer Industry Society
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• v.2 no.7
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• pp.895-904
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• 2001

In this study, gain can be high because an active double balance mixer was used. Receiving system II was made with receiving system I of low IIP3, a passive double balance mixer which has low gain and high IIP3, and an intermediate frequency amplifier for enhancing the low gain. The result of simulating receiving parameter is as follows： the total NF of receiving system I was 6.4382dB, gain was 53.5dB, and IIP3 was -6.6352dB m. As for the receiving system II, the total NF was 9.70672dB, gain was 47dB, and IIP3 was 3.66729dB m.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1419-1424
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• 2001

Previous research in our laboratory has demonstrated the importance of lactose in phase I and II pig starter diets. Two experiments were conducted to evaluate the use of a carbohydrate by-product (food by-products) as a replacement for lactose. In Exp. I, 120 weaned pigs ($14{\pm}2d$ and 5.65kg) were allotted in a randomized complete block design (RCBD) to 10 replications with four pigs per pen. This experiment evaluated three carbohydrate sources (lactose, carbohydrate by-product, and 50-50 blend of the carbohydrate by-product and lactose). The carbohydrate sources were added at 26% in the phase I diets and 15% in the phase II diets. Phase I diets contained 7.5% spray dried plasma protein (SDP). The phase I diets were fed from d 0 to 14 and the phase II diets from d 15 to 28. There were no significant differences between carbohydrate sources on pig performance in phase I. However, during phase II pigs fed the diet with lactose had an improved gain/feed ratio (G/F) (p=0.06) compared to pigs fed the carbohydrate by-product. For the entire 28 d trial ADG, ADFI and G/F were similar for the 50-50 blend and those fed lactose. Total replacement of lactose with the carbohydrate byproduct resulted in a reduced G/F (p=0.09). Exp. 2 used 100 weaned pigs ($17{\pm}2d$ and 4.75kg) with five replications with five pigs per pen. This experiment evaluated four carbohydrate treatments (lactose, carbohydrate by-products, 50-50 blend, and corn). All phase I diets contained 3.5% SDP with the carbohydrate sources included at 15%, and were fed d 0 to 14. The phase II diets contained 7.5% of the carbohydrate sources and were fed d 15 to 27. A common phase III diet was fed d 28 to 42. During all phases pigs fed com tended to have a lower ADG than pigs fed the other carbohydrate sources with the 50-50 blend resulting in the highest ADG. The results of both experiments suggest that this carbohydrate by-product can replace at least 50% of the lactose in phase I and phase II pig starter diets.