• Convergence Security Journal
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• v.16 no.6_1
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• pp.3-13
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• 2016

We take it for granted that strong sides defeat weaker counterparts, while predicting the outcome of the battles. But in modern war, we can find plenty of evidence that weak sides won against the strong. This phenomenon can be understood logically by the fourth-generation war theory. the North Korean does not give up its unification strategy, which is unification by force, even though its inferior power. It is continuing various political, social and military levels of provocations toward both the international community and South Korea. Recently, North Korea did nuclear test, launched ICBM test, provoked the DMZ, and expecting to continue the provocations of the fourth-generation war level. We have to understand the nature of North Korea's fourth-generation war threats and provocations that it is focusing on. Based on this, have a new understanding of the value of the Homeland Defense Reservists as fundamental measures as the fourth-generation war threat and supplement related systems. We can firmly refuse the balance of power and power shift of the Korean Peninsula through improved Homeland Defense Reservists. As the expected North Korea's the fourth-generation war threats, our Homeland Defense Reservists is a firm will of conduct war, and political-social-economic-military means, it is possible to display as the best alternative.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.305-313
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• 2020

The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

• Corrosion Science and Technology
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• v.13 no.2
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• pp.70-80
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• 2014

Duplex stainless steels with nearly equal fraction of the ferrite(${\alpha}$) phase and austenite(${\gamma}$) phase have been increasingly used for various applications such as power plants, desalination facilities due to their high resistance to corrosion, good weldability, and excellent mechanical properties. Hyper duplex stainless steel (HDSS) is defined as the future duplex stainless steel with a pitting resistance equivalent (PRE=wt.%Cr+3.3(wt.%Mo+0.5wt.%W)+30wt.%N) of above 50. However, when HDSS is welded with gas tungsten arc (GTA), incorporation of nitrogen in the Ar shielding gas are very important because the volume fraction of ${\alpha}$-phase and ${\gamma}$-phase is changed and harmful secondary phases can be formed in the welded zone. In other words, the balance of corrosion resistance between two phases and reduction of $Cr_2N$ are the key points of this study. The primary results of this study are as follows. The addition of $N_2$ to the Ar shielding gas provides phase balance under weld-cooling conditions and increases the transformation temperature of the ${\alpha}$-phase to ${\gamma}$-phase, increasing the fraction of ${\gamma}$-phase as well as decreasing the precipitation of $Cr_2N$. In the anodic polarization test, the addition of nitrogen gas in the Ar shielding gas improved values of the electrochemical parameters, compared to the Pure Ar. Also, in the erosion-corrosion test, the HDSS welded with shielding gas containing $N_2$ decreased the weight loss, compared to HDSS welded with the Ar pure gas. This result showed the resistance of erosion-corrosion was increased due to increasing the fraction of ${\gamma}$-phase and the stability of passive film according to the addition $N_2$ gas to the Ar shielding gas. As a result, the addition of nitrogen gas to the shielding gas improved the resistance of erosion-corrosion.

• The Journal of Internal Korean Medicine
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• v.29 no.1
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• pp.1-11
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• 2008

Objectives : Essential hyperhidrosis is a socially and occupationally disabling disorder. There are many suggestions that hyperhidrosis is associated with the autonomic nervous system. This study was designed to investigate the autonomic nerve system the patients with hyperhidrosis. Methods : 348 palmar and plantar hyperhidrosis patients and 20 systemic hyperhidrosis patients in the ambulatory care were investigated. All patients were inspected at the first medical examination, using the PSA of HRV. HRV was measured for 5 minutes after 5 minutes' bed rest. We checked the frequency domain analysis of HRV (i.e. TP, VLF, LF, HF and LF/HF) which were transformed into natural logarithm of patients against the standard measures of the HRV components. Then, we compared the means of patients with means and highest values of in the normal range of Koreans 1) between the patients with palmar and plantar hyperhidrosis and the healthy controls and 2) between the patients with the systemic hyperhidrosis and healthy controls, by the frequency domain analysis of heart rate variability (HRV), respectively. We then compared the results between 1) and 2). Results : The values of natural logarithmic measures of LF/HF ratio in the patients with palmar and plantar hyperhidrosis we examined were significantly higher than the values of healthy controls, but those in the patients with systemic hyperhidrosis were not higher. Conclusion : This study suggests that the autonomic nervous function did not simply increase but that the balance between sympathetic and parasympathetic nervous function did matter in patients with palmar and plantar hyperhidrosis. This balance included that the sympathetic nervous function aggravated comparatively with parasympathetic nervous function. On the other hand, we couldn't find any significance of the patients with the systemic hyperhidrosis as for the autonomic nervous function.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.2
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• pp.213-224
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• 2014

Recently, tunnelling with TBM is getting popular for the construction of cable tunnel in urban area. Mechanized tunnelling method using shield TBM has various advantages such as minimization of ground settlement and prevention of vibration induced by blasting that should be accompanied by conventional tunnelling. In Korea, earth pressure balance (EPB) type shield TBM has been mainly used. Despite the popularity of EPB shield TBM for cable tunnel construction, study on the mechanical behavior of cable tunnel driven by shield TBM is insufficient. Especially, the effect of backfill grout injection on the behavior of cable tunnel driven by shield TBM is investigated in this study. Tunnelling with shield TBM is simulated using 3D FEM. The distance of backfill grout injection from the end of shield skin varies. Sectional forces such as axial force, shear force and bending moment are monitored. Vertical displacement at the ground surface is measured. Futhermore, the relation between volume loss and the distance of backfill grout injection from the end of skin plate is derived. Based on the stability analysis with the results obtained from the numerical analysis, the most appropriate injection distance can be obtained.

• Archives of design research
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• v.13 no.1
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• pp.111-120
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• 2000

Certain complex forces are existing at the other side of a canvas. These are visual arrangements and within the arrangement, even the simple combination of dots and lines create more than visual patterns. No matter what form that visual art has taken, it is performed in a certain space and it is constucted with various visual elements. For effective communication, visual elements must form a stable sturcture by extablishing organic relationship among each other. These requires an understanding of the human visual characteristics and psychonology, because human sight senses the same biological and psychological visual elements differently in its force and weight, according to the position within a given space. Although the structure which controls such force and weight exists within a peice of work, it is a internal plan of the work that actually controls the communication through a man\ulcorner psychological reactions towards the horizontal and virtical structures within it. Moreover it is a visual statement that effectively expresses a theme or a message. This thesis has studied visual structures through the analysis of art pieces regarding of these kind of a visual picture plane, characteristics of a picture plane formed by a structure of force existing on the other side of the picture and the theory of visual balance. In addition, the aim of this study is to help designers who deals with visual image works to understand the visual structures and psychological recognitions and to apply these picture plane compositions at their real work by recognizing the psychological power within the construction elements.

• Journal of Family Resource Management and Policy Review
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• v.25 no.4
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• pp.1-14
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• 2021

This study was conducted to examine the realistic problems of flexible work arrangements, which was a representative policy for work-family balance, based on a review of its effect and influence on double-income couples who were actual users of the system. In this study, an in-depth interview with three double-income couples, totaling 6 parents, with preschool children was conducted on the experience of their flexible work arrangements, and the purposes of the study were to figure out their experienced positive effectiveness and the problems with the difficulty of using the system and to look for their solutions. For the data analysis of the study, it was organized into three high categories and nine low ones by reviewing the entire data on the basis of the frame structured in the derived data through the interview and categorizing the subjects by area. The derived analysis results were changes in households, social and cultural perspectives, and demand for policy and social economic changes. This study is significant in the sense that the perspectives and voice of the actual users of flexible work arrangements have been reflected in the study, and in the future, we expect that it will provide justification and persuasive power for the improvement of flexible work arrangements and serve as basic data for establishing policy directions and support.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.375-382
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• 2021

Adolescents with disabilities have unnatural behavior and language, which makes it difficult to use soft and flexible language and behavior, and lack of learning experience has limitations in not being free in mature behavioral communication. Eurhythmics musical rhythm elements were divided into time and space, power and weight, and balance and fluidity and reflected in teaching and learning so that adolescents with disabilities could have comfortable, creative, and original thoughts that bring about changes in thawing. In order to increase the effectiveness of education in the direction of observing the effect of improving self-esteem, communication, and creativity of adolescents with disabilities, the study guide applying the Eurhythmics rhythm element was fused with music education, art education, and physical education, and interviewed by selecting research participants. Based on the questionnaire, an observation method suitable for the study of adolescents with disabilities was conducted. As a result of the study, it was observed that the educational effect of the disabled youth was improved as a result of conducting the class by applying the Eurhythmics rhythm elements time and space, force and weight, balance and fluidity by integrating music, art, and physical education(line dance, playtime). Therefore, to supplement the limitations in this learning process, various educational methods applicable to the education of youth with disabilities, a support system that can reflect Eurhythmics education through physical play, and a method to properly compose various learning tools do.

• Journal of the Korean Applied Science and Technology
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• v.38 no.6
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• pp.1627-1642
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• 2021

This study aims to evaluate physical fitness according to the bone age of youth, and ultimately provide basic data for balanced development of youth through physical fitness standard indicators according to the bone age. A total of 730 youth aged 11 to 13 years in bone age and 11 to 13 years in chronological age were selected as subjects; and after taking X-ray films to calculate the bone age, they were evaluated by using the TW3 method. A total of 2 components in physique, which were stature and weight, were measured using a stadiometer(Hanebio, Korea, 2021) and Inbody 270(Biospace, Korea, 2019). A total of 7 components in physical fitness were measured as well, which included muscular strength (Hand Grip Strength), balance (Bass Stick Test), agility (Plate Tapping), power (Standing Long Jump), flexibility (Sit&Reach), muscular endurance (Sit-Up), and cardiovascular endurance (Shuttle Run). Descriptive statistics and independent t-test were conducted for data processing using the SPSS PC/Program(Version 26.0), and it was considered significant at the level of p< .05. The results of this study may be summarized as follow. First, the result of comparing the bone age and the chronological age of 11 to 13 years old in physical fitness, males showed significant difference in muscular strength, power, muscular endurance, and cardiovasular endurance. In females, muscular strength, balance, agility, power, flexibility, muscular endurance, and cardiovascular endurance showed significant difference. Second, physical fitness standard indicators were presented for each gender and age (11-13 years old) of youth according to the bone age; and based on this, physical fitness standard indicators, which are basic data for physical fitness evaluation according to the bone age of youth, were presented.

• Clean Technology
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• v.19 no.2
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• pp.165-172
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• 2013

In this study, the hydrogen chloride removal using K-based dry sorbents ($K_2CO_3/Al_2O_3$, KEPRI, Korea) was studied with varying the pressure in a fixed bed reactor (15 cm tall bed with 0.5 cm I.d.). Working temperature was $400^{\circ}C$ and feed gas concentration was 750 ppm (HCl vol%, $N_2$ balance). The chloride sorption capacity of sorbent increases with increasing pressure (1, 5, 10, 15 and 20 bar). Also, after forming KCl crystal by reaction with $K_2CO_3$ and HCl, owing to the strong bonding energy, sorbent regeneration was practically impossible. Its optical, physical and chemical characterizations were evaluated by SEM, EDAX, BET, TGA and XRD. At $400^{\circ}C$ and 20 bar condition, working condition for the dehalogenation process after gasification, K-based dry sorbent showed high HCl sorption capacity and HCl/$N_2$ separation performances comparing with Ca-based and Mg-based dry sorbents.