• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.121-125
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• 2022

As the technologies of the 4th industrial revolution develops, spatial information is becoming digitized. Now, even with a smartphone, we can easily identify the location of national & military critical facilities located in the mega cities. As a result, mega cities' national & military critical facilities were exposed to not only traditional threats, but also non-traditional threats such as terrorism, cyber hacking, and criminal activities. This study suggests a way to protect national & military critical facilities of mega cities from such threats. Considering limitation of time & resources, protecting perfectly all national & military critical facilities is impossible, so we should focus on their critical nodes. Specifically, We suggest ways to protect the critical nodes by converging some measures such as design & arrangement in harmony with the surrounding environment, underground construction & covering, and visual deception. Transparency of digital spatial information will further increase with the advent of urban air mobility and autonomous vehicles in the future. Therefore, in order to prepare for future threats, we should take measures to minimize the exposure of critical nodes.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.227-232
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• 2015

This experiment was carried out to investigate the effects of shading materials (aluminum specific-shading screen and polypropylene non-woven fabric) and shading ratio (50% and 70%) on climatic changes, cut-flower quality, and yield of spray rose cultivars for export during high temperature periods. The daily cumulative solar radiations were higher with the aluminum specific-shading screen, especially with 50% shading compared to polypropylene non-woven fabric. Air temperature and root zone temperature within rockwool media greatly decreased with the aluminum specific-shading screen, but relative air humidity was not different among shading methods. Chlorophyll contents (SPAD values) were slightly higher with aluminum-specific shading screen than with polypropylene non-woven fabric, and were higher with 50% than with 70% aluminum specific-shading screen. Except for 'Lovely Lydia', marketable and exportable yields of all cultivars were higher with 50% than with 70% aluminum shading treatment. In addition, flowers talk length, stem diameter, number of node and 7ea-leaflet, and floret number tended to be better with aluminum specific-shading screen. Flower stalk length was higher with 70% than with 50% aluminum shading treatment. Chromaticity of petals slightly increased, and vase life was 0.5-2.5 days longer for each cultivar with aluminum specific-shading screen than with polypropylene non-woven fabric.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.131-139
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• 2022

In this paper, to verify the authenticity of UxNB that assists terrestrial base stations, the solutions for SI (System Information) security presented in 3GPP TR 33.809 are analyzed from the perspective of UxNB. According to the definition of 3GPP (Third Generation Partnership Project), UxNB is a base station mounted on a UAV (Unmanned Aerial Vehicle), is carried in the air by the UAV, and is a radio access node that provides a connection to the UE (User Equipment). Such solutions for SI security can be classified into hash based, MAC (Message Authentication Codes) based, and digital signature based, and a representative solution for each category is introduced one by one. From the perspective of verifying the authenticity of UxNB for each solution, we compare and analyze the solutions in terms of provisioning information and update, security information leakage of UxNB, and additionally required amount of computation and transmission. As a result of the analysis, the solution for verifying the authenticity of the UxNB should minimize the secret information to be stored in the UxNB, be stored in a secure place, and apply encryption when it is updated over the air. In addition, due to the properties of the low computing power of UxNB and the lack of power, it is necessary to minimize the amount of computation and transmission.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.212-220
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• 2022

When it comes to single node leafy stem cuttings of rose (Rosa hybrida), environmental management such as air temperature, relative humidity, and light affect productivity. In order to investigate the effect of air temperature and relative humidity on the cutting success rate and rooted cuttings quality, a transparent airtight box was used to implement a closed system. We have also tried to find out the most effective photoperiod and the number of leaflets in closed system using artificial light (white LED, 104.0 µmol·m^-2·s^-1 photosynthetic photon flux density). The first experiment was conducted for a total of 6 weeks under 4 airtight period conditions. The number of roots and longest root length decreased as the airtight period increased. But there were no significant differences in the survival rate, shooting rate, and rooting rate according to airtight periods. In the second experiment the results indicated that survival and shooting rate were significantly affected by the photoperiod (0/24, 2/22, 4/20, 8/16, and 16/8 h), the number of leaflets (0, 2, and 4 leaflets) of the cuttings and their interaction. The survival rate was the highest in the 16-h day length and 4 leaflets. By considering survival rate and shooting rate with energy efficiency, the 8-h day length and 2 or 4 leaflets were judged to be the most effective.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.609-620
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• 2023

In this study, we used Sentinel-1 C-band synthetic aperture radar to calculate the surface state factor (SSF) for distinguishing the frozen-thawed state of soil. The accuracy of SSF classification was analyzed through comparison with air temperature (AT), grass temperature (GT), and underground temperature (UT). For the analysis, 116 Sentinel-1B Descending nodes observed over a period of 4 years from 2017 to 2020 were established for the central region of South Korea. AT, GT, and UT data were obtained from 23 soil moisture observation points of the Rural Development Administration during the same period, and analyzed using the 06:00 am data adjacent to the shooting time of the Sentinel-1B images. The average accuracy and F1-score for all stations were 0.63 and 0.47 for AT, 0.63 and 0.48 for GT, and 0.57 and 0.21 for UT, respectively. For winter (December-February) data, the average accuracy and F1-score were 0.66 and 0.76 for AT, 0.67 and 0.76 for GT, and 0.47 and 0.44 for UT, respectively. The increase in accuracy during winter data may be attributed to the fact that errors occurring in other seasons are not included.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.33-38
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• 2010

Background: The use of video-assisted thoracic surgery (VATS) to perform major pulmonary resection with systematic node dissection (SND) for lung cancer by is commonly used in clinics. However, the feasibility of SND by VATS remains controversial. Video-assisted mediastinal lymphadenectomy (VAMLA) increases the quality of mediastinal lymph node staging in lung cancer. The video-mediastinoscope allows systematic lymphadenectomy by bimanual preparation. This study was conducted to assess safety and usefulness and clinical feasibility of VAMLA expanding Linder-Dahan mediastinoscope with VATS lobectomy for left sided lung cancer. Material and Method: Between February 2004 to April 2008, a total 50 patients who underwent VATS lobectomy for left sided lung cancer were analyzed retrospectively. Thirty patients (group A) underwent VAMLA followed by VATS lymphadenectomy and 20 patients (group B) underwent VATS lymphadenectomy for SND. Result: There were no statistical differences in operation times, chest tube indwelling times, or hospital days between the 2 groups. The number of dissected total nodes (p=0.001) and N2 nodes (p=0.013) were higher in group A than in group B, but there was no difference in N1 nodes. Postoperative complications included 2 prolonged air leakages (${\geq}$10 days) in each group, one pneumonia in group A, and one vocal cord palsy in group B. There were no early operative mortalities. Conclusion: Mediastinal staging of resectable lung cancer is performed by VAMLA. This new technique is the basis for VATS lobectomy particularly for left-sided lung cancer, because a higher percentage of mediastinal lymph nodes undergo complete resection using VAMLA.

• The Journal of Korean Obstetrics and Gynecology
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• v.33 no.2
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• pp.77-89
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• 2020

Objectives: The purpose of this study is to analyse current status and treatment of the Korean medicine hospital after chemotherapy in patients with breast cancer. Methods: We investigated the medical records of 21 patients who admitted to Korean medicine hospital after chemotherapy in patients with breast cacner from March 1, 2017 to December 31, 2019. We searched medical records retrospectively and analyzed current status and treatment of Korean medicine hospital. Results: The average age of 21 participants was 52.81±8.38 years and 40s and 50s accounted for 85.6% of the total. After receiving chemotherapy, the average time to hospitalization was 1.87±3.13days and average hospital stay was 9.78±4.14 days. The subjects were classified as 28.6% of stage I, 52.4% of stage II, 9.5% of stage III, and 9.5% of stage IV. The analysis according to the presence of metastasis was 57.1% without metastasis, 33.3% with axillary lymph node metastasis, and 9.5% with distant metastasis. The main symptoms complained when hospitalized by 21 subjects were nausea (54.2%), fatigue (54.2%), and anorexia (50.8%) in over 50%, pantalgia (47.5%), and insomnia (47.5%), dizziness (44.1%), cold sweating (42.4%), lower extremity pain (40.7%), 37.5~37.9℃ fever (39.0%), headache (37.3%), hot flush (37.3%), pruritus (30.5%) are 30% or more. Korean medicine treatment was performed in 87.4% of all hospitalizations and Gwakhyangjunggi-san-gami was the most administered prescription. Extracts of Korean medicine was performed in 100.0% of all patients and Eunkyo-san was most administered extracts medicine. Acupuncture, moxibustion, and cupping treatments were performed in all 21 study subjects. Other treatments was performed at a frequency of hyperthermia (90.5%), lymph massage (23.8%), air compression therapy (23.8%), and Interference current therapy (19.0%) Conclusion: Korean traditional medicine can be used as a countermeasure for side effects after chemotherapy in breast cancer patients.

• Journal of the Korea Society of Computer and Information
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• v.19 no.3
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• pp.63-71
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• 2014

We analyze the execution time of Reed-Solomon coding, which is the MAC-layer forward error correction scheme used in CDMA2000 1xEV-DO broadcast services, under different air channel conditions. The results show that the time constraints of MPEG-4 cannot be guaranteed by Reed-Solomon decoding when the packet loss rate (PLR) is high, due to its long computation time on current hardware. To alleviate this problem, we propose three error control schemes. Our static scheme bypasses Reed-Solomon decoding at the mobile node to satisfy the MPEG-4 time constraint when the PLR exceeds a given boundary. Second, dynamic scheme corrects errors in a best-effort manner within the time constraint, instead of giving up altogether when the PLR is high; this achieves a further quality improvement. The third, video-aware dynamic scheme fixes errors in a similar way to the dynamic scheme, but in a priority-driven manner which makes the video appear smoother. Extensive simulation results show the effectiveness of our schemes compared to the original FEC scheme.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.12
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• pp.874-880
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• 2019

This paper introduces a method which can be effectively used for the path planning of UAV in a realistic map which has mountainous terrains, air defense networks and radars based on the Visibility Graph. Existing studies of Visibility Graph have been studied mainly for simple shape obstacles in 2-dimensional environment such as self-driving cars which avoid buildings. However, for UAV, Visibility Graph must be used in 3-dimensional environment for the variance of altitude. This occurs significant elapsed time increase because of the increase of the amount of the visibility of node sets. To solve this problem, this paper decrease the number of nodes which consists the complex terrain environments using convex hull based on Layered Visibility Graph. With convex hull method, this paper confirmed that the elapsed time is decreased about 99.5% compared to the case which has no decrease of the number of nodes.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.4
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• pp.381-388
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• 2015

In this paper, a wireless video streaming system is designed and implemented for TV white space applications. It consists of a RF transceiver module, a digital modem, a camera, and a LCD screen. A VGA resolution video is captured by a camera, modulated by modem, and transmitted by RF transceiver module, and finally displayed at a destination 2.6-inch LCD screen. The RF transceiver is based on direct-conversion architecture. Image leakage is improved by low pass filtering LO, which successfully covers the TVWS. Also, DC offset problem is solved by current steering techniques which control common mode level at DAC output node. The output power of the transmitter and the minimum sensitivity of the receiver is +10 dBm and -82 dBm, respectively. The channel bandwidth is tunable among 6, 7 and 8 MHz according to regulations and standards. Digital modem is realized in Kintex-7 FPGA. Data rate is 9 Mbps based on QPSK and 512ch OFDM. A VGA video is successfully streamed through the air by using the developed TV white-space RF communication module.