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The Immunohistochemical Expression of Collagens and the Morphogenesis in the Developing Mandible of Human Embryos and Fetuses (배자와 태아에서 하악골의 형태발생 및 교원질 발현에 관한 면역조직화학적 연구)

  • Kook, Yoon-Ah;Kim, Sang-Cheol;Kim, Eun-Cheol;Kim, Oh-Hwan;Kim, Jong-Ghee
    • The korean journal of orthodontics
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    • v.26 no.2 s.55
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    • pp.187-196
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    • 1996
  • Underlying malocclusions and dentofacial deformities are often related to variations in the craniofacial development. Type I and type II collagens are considered the major collagens of bone and cartilage respectively. Monitoring the patterns of those protein expressions during development will Provide a basis for the understanding of normal and abnormal growths. This study was undertaken to investigate the morphogenetic changes and the expression patterns of type I and II collagen proteins involved in the developing mandible of human embryos and fetuses. 50 embryos and fetuses were studied with Hematoxylin and Eosin, Alcian, blue-PAS, Masson Trichrome, md Immunohistochemical stains. The results were as follows : 1. A 13.5 mm embryo showed the stomatodeum with dental lamina, maxillary and mandibular processes. Meckel's cartilage appeared in the mandibular arch of a 20.5 mm embryo. New bone formation was bilaterally initiated at the outer side of middle portion of Meckel's cartilage of 22-38 mm embryos. 2. Meckel'cartilage was resorbed at the 15th week fetus. The endochondral ossification was observed where there was direct replacement of cartilage by bone. Meckel'cartilage disappeared and membraneous ossification were observed at the 25th week. 3. Before the appearance of Meckel's cartilage, the expression of type I collagen was moderate at the odontogenic epithelium of maxillary & mandibular process, but mild for the expression of type II collagen. 4. During the appearance of Meckel's cartilage and new bone formation, the immunoactivity of type II collagen was more expressed than type I collagen at the Meckel's cartilage and new bone. 5. During intrarmembranous bone formation, the expression of type II collagen was rare in the bony trabeculae. There was a switch for the expression of collagens from type II to type I during the appearance of Meckel's cartilage.

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호스피스와 종교적 죽음이해

  • Sin, Min-Seon;Kim, Mun-Su
    • Korean Journal of Hospice Care
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    • v.6 no.1
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    • pp.1-11
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    • 2006
  • There are various understandings how to define death. In the context of medicine, death is defined as the irreversible change of the tissue according to the cessation of circulation and respiration. According to the psychologists, a person need to accept the finiteness as a human being and remain conscious that the death is not avoidable. And they say if a person doesn't regard death as unavoidable reality of life he or she will not confront the humanistic death and after all will die like animals. In philosophy, death is viewed as an unwelcome reality in the end of the journey of life. Sociologists usually understand that the society is the organization composed with living persons and human beings which construct and transmit the culture from generation to generation between the both ends of life and death. In society, the generation is changed, maintained, and developed through the phenomenon of death. Although death of human being is natural event in society, the death of a specific person brings a sense of loss, crisis, and anxiety to the communities like family, regional society, nation, and the world. In this context, death is not confined to personal dimension and it can be regarded as a social problem. It is valuable to summarize the religious perspectives on the meaning of death for the better hospice care. In shamanism, there are basic idea that although the flesh of human being disappears, soul never die. If human dies, the flesh of human being disappears but soul never disappear and come back to the origin of soul as it is called chaos. So in shamanism, it is said that shaman can solve the mortified feeling, restore the broken harmony, send the soul to comfortable space- the origin, and guarantee the blessing of descendents. Buddhists regard the death as an essential component through the cycles of life. Through this cycle, human being exits as an endlessly transmigrating being and the death is just a restoration to the original status. In Confucianism, the view on the death based on the philosophy of the "Yin and Yang" and "Five elements". In Buddhist tradition, many believers said the philosophy of "Death is the same as life". Unlike usual thoughts that a god governs "life and death" and "fortune and misfortune", Confucianists deny the governance of a god and emphasize the natural orders in which every phenomenon in the world moves according to the principle. Confucianists understand the death as a natural order with this principle. In Confucianists' belief, the essence of human being remains in their own descendent's lives after the death of ancestor, so in Confucianism there is no concept of immortality of the soul. In the history of Christianity, death has been defined generally as the separation of the immortal soul from the mortal body. In the earlier days of Old Testament, the death is regarded as a disappearance of just a flesh and human never disappear and always live in the relationship with God. Later days in Old Testament, we can find the growing concern for the life after the death because of the entrance of the theodicy. In the New Testament, the death is not regarded as the normal process of the human life and regarded as the abnormal status in which death come to human because of sin as a decisive factor and it should be conquered. In fact, the most of us afraid death because not of the fear of death itself but of the sense of the emptiness and regrets. so many people often make the monument hoping to live forever. But Christian usually regard this behavior as a sinful act because human being usually think themselves as a master of their life and attempt to become immortal in this kind of trial mortal. But if we live with God, we cannot confront such a condition because we aware limits as a mortal human being and entrust everything on Him and want to live according to His guidance. Therefore, in the Christian tradition, the death is regarded as accomplishment of life, fruits of life, invitation to the eternal life, and the last stage of human growth. For human being, the death is the great step of maturation as a human in the final stage of life.

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Three dimensional photoelastic study on the initial stress distributions of alveolar bone when retracted by lingual K-loop archwire (Lingual K-loop archwire를 이용한 발치공간 폐쇄시 초기응력 분포에 대한 3차원 광탄성학적 연구)

  • Byun, Bo-Ram;Kim, Sik-Sung;Son, Woo-Sung
    • The korean journal of orthodontics
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    • v.32 no.5 s.94
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    • pp.343-353
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    • 2002
  • This study was designed to investigate the stress distribution of alveolar bone in case of on masse retraction with lingual K-loop archwire using the 3-dimensional photoelastic stress analysis followed by stress freezing process. Lingual K-loop archwire which had loop in 15mm height was used and activated by retraction force of 350gm per each side. The results were as follows 1. Central incisor : As the closer side to crown, the larger tensile stress was distributed at both mesial and labial surfaces and the larger compressive stress was distributed at distal surface. As the closer side to root apex, the larger compressive stress was distributed at lingual surface. The compressive stress was distributed at root apex. 2. Lateral incisor : The tensile stress was distributed at the coronal side of mesial surface. The compressive stress was distributed at distal surface. As the closer side to crown, the larger tensile stress was distributed at labial surface. The tensile stress was distributed at coronal side and the compressive stress was distributed at apical side of lingual surface. The compressive stress was distributed at root apex. 3. Canine The tensile stress was distributed at coronal side and the compressive stress was distributed at apical side of mesial surface. The tensile stress was distributed at distal surface. As the closer side to crown, the larger tensile stress was distributed at both mesial and distal surfaces. The compressive stress was distributed at root apex. 4. Second premolar : The tensile stress was distributed at mesial surface. The compressive stress was distributed at coronal side and the tensile stress was distributed at apical side of distal surface. The compressive stress was distributed at coronal side of buccal surface. As the closer side to crown, the larger tensile stress was distributed at lingual surface. The compressive stress was distributed at root apex. 5. First molar . As the closer side to crown, the larger tensile stress was distributed at both mesial and distal surfaces. No stress was distributed at buccal surface and palatal root apex. As the closer side to crown, the larger tensile stress was distributed at both lingual surfaces. The compressive stress was distributed a4 buccal root apexes. 6. Second molar The compressive stress was distributed at all root apexes. As the closer side to crown, the larger compressive stress was distributed at both mesial and lingual surfaces, and the larger tensile stress at both distal and buccal surfaces. Transverse bowing effect was observed in on-masse retraction with lingual K-loop archwire, however vertical towing effect was not. Rather, reverse vortical bowing effect was developed.

The effects of pregnancy on alveolar bone turnover during experimental tooth movement in rats (백서에서 실험적 치아이동시 임신이 치조골 교체(Turnover)에 미치는 영향에 대한 연구)

  • Kim, Young-Sun;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.30 no.4 s.81
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    • pp.413-421
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    • 2000
  • The purpose of this study was to observe the effects of pregnancy on the experimental tooth movement and alveolar bone turnover process of Sprague-Dawley female rat. Sixty rats were divided into pregnant-tooth movement group(P-Tm), normal-tooth movement group(N-Tm) and normal group(N). Maxillary first molar appliances were inserted bilaterally and activated to 40grams. To measure the amount of tooth movement, x-ray was taken 2 times after appliance insertion and before sacrifice. Animals were sacrificed at 1,3,7,14 days(N=5). Just after sacrifice, alveolar bones were collected and frozen immediately for biochemical analysis. Tooth movement was assessed cephalometrically and tartrate-resistant acid(TRAP) and alkaline phosphatase (ALP) activities were measured in extracts of paradental alveolar bone. The results were as follows: 1. The amount of tooth movement in P-Tm group was greater than that of N-Tm group(p<0.01). 2. Alveolar bone ALP of normal tooth movement group was not significantly different from the control, TRAP was significantly different from the control(p<0.01). In normal tooth movement group, alveolar bone ALP was increased gradually and peak(day 7) fell off significantly at day 14(p<0.05). The Peak of alveolar bone TRAP(day 7) fell off slightly, sustained day 14(p<0.01). 3. Alveolar bone ALP and TRAP of pregnant tooth movement group were not significantly different from that of normal tooth movement group. In pregnant tooth movement group, alveolar bone ALP was increased at day 3(p<0.01) and fell off significantly at day 7-14, alveolar bone TRAP were increased at day 3 and sustained day 14. 4. The peak of alveolar bone phosphatases in pregnant tooth movement group(day3) preceded the peak in normal tooth movement group(day7) (p<0.01). According to the above results, we suggested that bone resorption activity was increased in alveolar bone of pregnant rat, and the degree of tooth movement in pregnancy may be greater than that of normal group because of high bone turnover of alveolar bone in pregnant rat.

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National Survey of Injury and Poisoning on a Representative Sample Population of Koreans (우리나라 대표적(代表的) 표본인구(標本人口)의 연간(年間) 손상(損傷) 및 중독발생율(中毒發生率)과 역학적(疫學的) 특성(特性))

  • Kim, Joung-Soon;Kim, Sung-Soo;Chang, Sung-Chill
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.3 s.47
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    • pp.447-463
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    • 1994
  • Despite the public health importance of injury and poisoning in terms of its high mortality and incidence, epidemiologic information to be utilized are scarce in Korea. This study was carried out in 1990 on a representative sample population (about 55,000 persons) along with the 6th National Tuberculosis Prevalence Survey in order to estimate the magnitude of injury and poisoning occurrence and to identify its epidemiologic characteristics which can be aided for establishing preventive strategy. Pre-tested and structured Questionnaire was used by trained interviewer to collect data including general information of the person, various information on the injury and poisoning during the past one year such as time and place of its occurrence, its nature and external causes, type of medical institute attended, duration of treatment and outcome of the accident occured. In analysis of the data collected incidence rates per 1000 persons by sex, age group and its nature as well as external causes, and relative frequencies were calculated. The result obtained are as followings; 1. The incidence rate per 1000 was 30 for both sexes, 39 for male and 22 for female, male being 1.8 times more frequent than female. Age adjusted incidences were not much different from the crude rates. Age group specific rate curve showed bimodal shape in both sexes, small peaks in preschool children and higher peaks in older ages. The incidence rate per 1000 people by area was highest in Jeon-bug province (57/1000) and the lowest in Daegu city(11/1000). 2. The place where the injuries occured were road in 46%, within the boundary of house in 25%, and working place in 12% The injuries and poisoning had occured more frequently during the months from March to August of the year than other months. 3. The relatively frequent injuries by its nature were contusion with intact skin surface (19%), fracture of upper limb (13%), open wound of head, neck and trunk (12%) and fracture of lower limb (11%) among males; contusion with intact skin surface (28%), sprains and strains of joints and adjacent muscle (14%), fracture of upper limb (10%) and fracture of lower limb (9%) among females. Higher incidence rate among males than females were fracture of skull (4.5 times), open wound and fractures of limbs ($2{\sim}3$ times). Age specific rate of injuries and poisoning by its nature showed increasing pattern by age in fractures of upper and lower limbs and sprains & strains of joints whereas the age group of 30's showed highest incidence in open wounds of upper limb. Fractures of radius and ulna in upper limb, fractures of tibia & fibula and ankle in lower limb were most frequent among fractures of upper and lower limbs. The frequent injuries among sprains and strains of joints and adjacent muscles were that of ankle, foot and back, and among open wound were that of head and fingers. 4. Relative frequency of injuries and poisoning by external causes showed following order : other accidents (25%), accidental falls (23%), motor vehicle accident (22%) and other road vehicle accident (14%) among males and accidental falls (37%), motor vehicle accident (24%) and other accident (18%) among females. The external causes revealing higher incidences among males than females, were other road vehicle accident (4.8 times), vehicle accident not elsewhere classifiable (4.4 times), accidental poisoning (4.4 times), accidents due to natural and environmental factors (2.8 times), and sucide & self-inflicted injuries (2.8 times). Age specific incidence by external causes for frequent injuries showed that incidence of other accident steadily increased from 10's till age 50's; motor vehicle traffic accident increased from age 20's and dropped after age 60's; on the other hand accidental fall increased strikingly by age. The most frequent external causes among motor vehicle traffic accidents was motor vehicle traffic accident involving collision with pedstrain (69%), pedal cycle accident (30%) and other road vehicle accident (71%) among other road vehicle accidents; falls on same level from slipping, tripping or standing (44%) and other falls from one level to another among accidental falls; accidents caused by machinary (32%) for male and striking against or struck accidentally by objects or person for female among other accidents. 5. Seventy nine percent of the injuries and poisonings were treated in general hospital or hospital/clinic. The duration of treatment ranged from a few days to 123 weeks; the majority(52%) took under 2 weeks, 36% for $3{\sim}8$ weeks and 4% over 21 weeks. 6. The accident resulted in full recovery of normal healthy state in 62%, residual functional defects in 21% and on process of treatment in 16%.

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A Funding Source Decision on Corporate Bond - Private Placements vs Public Bond - (기업의 회사채 조달방법 선택에 관한 연구 - 사모사채와 공모사채 발행을 중심으로 -)

  • An, Seung-Cheol;Lee, Sang-Whi;Jang, Seung-Wook
    • The Korean Journal of Financial Management
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    • v.21 no.2
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    • pp.99-123
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    • 2004
  • We focus in this study on incremental financing decisions and estimate a logit model for the probability a firm will choose a private placement over a public bond issue. We hypothesize that information asymmetry, financial risk, agent cost, and proprietary information may affect a firm's choice between public debt and private placements. We find that as the size of firm increases, the probability of choosing a private placement declines significantly. The age of the firm, however, is not a significant factor affecting the firm's choice between public and privately-placed bond. The coefficients on the firm's leverage and non-investment grade dummy are significantly positive, meaning firms with high financial risk and credit risk select private placements. The findings regarding agency-related variables, PER and Tobin's Q, are somewhat complex. We find significant evidence that firms with high PER prefer private placements to public bonds, suggesting that borrowers with options to engage in asset substitution or underinvestment are more likely to choose private placements. The coefficient of Tobin's Q is negative, but not significant, which weakly support the hold-up hypothesis. When we construct an interaction term on the Tobin's Q with a non-investment rating dummy, however, the Tobin's Q interaction term becomes positive and significant. Thus, high Tobin's Q firms with a speculative rating are significantly more likely to choose a private placement, regardless of the potential hold-up problems. The ratio of R&D to sales, proxy for proprietary information, is positively significant. This result can be interpreted as evidence in favor of a role for proprietary information in the debt sourcing decision process for these firms.

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An Analysis of Validity and Satisfaction for Objectives of Small and Medium Business(SMB) Administration Subsidy the Human Resource Development Program(HRDP) and the Customized Employment Program(CEP) in Specialized High Schools (중소기업 특성화고 인력양성사업과 취업맞춤반의 성과 목표에 대한 타당도 및 만족도 분석 연구)

  • Lee, Byung Wook;Ahn, Jae Yeong;Kang, Chol Min
    • 대한공업교육학회지
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    • v.41 no.1
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    • pp.68-87
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    • 2016
  • This research conducted a survey for total 166 teachers of schools so as to analyze validity and satisfaction for performance objectives of SMB administration subsidy the HRDP and the CEP in Specialized High School. The results of research are as follows. First, teachers recognize that purpose of HRDP is to expand employment of specialized high school and provide human resource of SMB. And, they recognize that HRDP is important to improve school outcomes and makes a positive effect on the improvement of school outcomes. Second, teachers recognize that objectives of HRDP are improvement of student's understanding for SMB, improvement of teacher's understanding for SMB, improvement of SMB's understanding of school, cultivation of student's occupational view, systematization of career guiding program based on employment process, strengthening of industry-academia cooperation education, improvement of the level of student's skill, fulfillment of workplace experience and practice focusing workplace learning, training of customized human resource for SMB, improvement of student's adaptation to the workplace, improvement of employment rate for SMB, expansion of job opportunities for students with SMB, preparation of the base of connection between school and SMB, publicity of school, expansion of opportunities to cooperate between SMB and school, establishment of cooperative system among industrial association and school, introduction and operation of the employment connective model for joint education and employment, strengthening of field professionalism of teachers. However, satisfaction for the achievement of objectives of HRDP except for strengthening of industry-academia cooperation education and improvement of employment rate for SMB is relatively lower than the validity. Third, teachers in charge of human resource training business of middle and small sized company's specialized high school recognize that objectives of CEP are expansion of job opportunities for students with SMB, excavation of good-quality SMB, expansion of opportunities to cooperate between SMB and school, fulfillment of workplace learning, improvement of student's major foundation and in-depth skill, improvement of literacy, math, teamwork and communication abilities for students' job performance, improvement of student's working attitude and student's proper career exploration decision. However, satisfaction for achievement of objectives of CEP is relatively lower than the validity.

An Analysis of Terrorism against Korea to Overseas and its Implications - Focusing on the companies advancing to overseas - (한국을 대상으로 한 국제테러리즘의 분석과 시사점 - 해외진출기업을 중심으로 -)

  • Chang, Suk-Heon;Lee, Dae-Sung
    • Korean Security Journal
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    • no.28
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    • pp.153-179
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    • 2011
  • Korea has been a victim of State supporting terrorism by North Korea even before international society realize the terrorism threats because of 9.11 in US. However, state supporting terrorism against South Korea by North Korea went along with East/West Cold War System by US and the Soviet Union. It is because socialism that Kim Il-sung who established a separate government in North Korea with the political, economic, social and military support of the Soviet Union selected as his political ideology justifies terrorism as the tool to complete the proletariat revolution. North Korea's state supporting terrorism is being operated systematically and efficiently by military of North Korea. It gives big worries to international society not only by performing terrorism against Korea but also by dispatching terrorists and exporting terrorism strategies to the third world countries. In this situation, terrorism against Korea has met a new transition point at 9${\cdot}$11 in US. As South Korea is confronting North Korea and the war has not ended but suspended, the alliance between US and Korea is more important than anything else. Because of this Korea decided to support the anti-terrorism wars against Afghanistan and Iraq of US and other western countries and send military force there. The preface of the anti-terrorism war has begun as such. On October 7, 2001, US and UK started to attack Afghanistan and Taleban government in Afghanistan was dethroned on December 7, 2001. US and western countries started a war against Iraq on March 20, 2003. On April 9, 2003 Baghdad, the capital of Iraq fell, and Saddam Hussein al-Majid al-Awja government was expelled. During the process, the terrorism threat against South Korea has expanded to Arab terrorists and terrorism organizations as well as North Korea. Consequently, although Korean government, scholars and working level public servants made discussions and tried to seek countermeasures, the damages are extending. Accordingly, terrorism against Korean companies in overseas after 9${\cdot}$11 were analyzed focusing on Nation, Region, Victimology, and Weapons used for the attacks. Especially, the trend of terrorism against the Korean companies in overseas was discussed by classifying them chronologically such as initiation and termination of anti-terrorism wars against Afghanistan and Iraq, and from the execution of Iraqi President, Saddam Hussein al-Majid al-Awja to December 2010. Through this, possible terrorism incidents after the execution of Osama bin Laden, the leader of Al-Qaeda, on May 2, 2011 were projected and proposals were made for the countermeasures.

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The structural relationships between organizational ethical, job satisfaction and organizational citizenship behavior of private security guards (민간경비원의 조직윤리, 직무만족 및 조직시민행동의 구조적 관계)

  • Kim, Young-Hyun;Park, Kill-Jun
    • Korean Security Journal
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    • no.42
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    • pp.59-85
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    • 2015
  • The purpose of this study is to establish the structural relationship among organizational ethical climate, job satisfaction, and organizational citizenship behavior. It was intended for the private security guards who work in the security companies in Seoul and Gyeonggi from Jan. 1st, 2014 to Apr. 1st, 2014 to achieve the purpose like this. Purposive sampling was used as the sampling method according to this and sampling of 400 persons was done. However, the samples of 372 persons were finally used in the analysis through the process to check faithless answers, double answers, and abnormal data. The collected data was analyzed according to the purpose of the study by utilizing STATA 13.0 and AMOS 17.0. And for statistic techniques, frequency analysis, descriptive analysis, multivariate normality, confirmatory factor analysis(CFA), Pearson's correlation analysis, and structural equation model analysis were carried out. The conclusion gotten from this study through the data analyses according to the methods and procedure like this is as follow: First, organizational ethical climate has found to have the positive effect on job satisfaction(Non-standard $B=1.427^{***}$). That is, it can be interpreted that organizational ethical climate positively affects superiors, fellow employees, pay, current duties, and chances of promotion. Second, job satisfaction has found not to have the significant effect on organizational citizenship behavior. That is, it can be interpreted that job satisfaction does not affect altruism, conscience, and participation behavior. Third, organizational ethical climate has found to have the positive effect on organizational citizenship behavior (Non-standard $B=.361^{***}$). That is, it can be interpreted that organizational ethical climate positively affects altruism, conscience, and participation behavior. Fourth, the relationship between organizational ethical climate and organizational citizens has found that there is no any indirect effect in the bootstrapping estimation result to establish the indirect effect of job satisfaction. Fifth, the relationship between organizational ethical climate and job satisfaction has found that there are the moderating effects in the analytical result of the moderating effects of person-organization fit. That is, the effects of organizational ethical climate on job satisfaction have found that the groups with higher person-organization fit are more positive than those with lower person-organization fit. Sixth, the relationship between job satisfaction and organizational citizenship behavior has found that there are moderating effects in the analytical result of person-organization fit. That is, the effects of job satisfaction on organizational citizenship behavior have found that the groups with higher person-organization fit are more positive than those with lower person-organization fit.

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A study on factors affecting high school students of school violence - Focusing on personality factors - (고등학생의 학교폭력에 영향을 미치는 요인에 관한 연구 : 인성요인을 중심으로)

  • Lee, Jung-Duk;Chang, Jeong-Hyeon
    • Korean Security Journal
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    • no.42
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    • pp.393-422
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    • 2015
  • The school is committed to the role of public education for the effective development of student academic achievement and intellectual ability. It is also a space to expand the range of care and understanding for others with as a member of the academic community as well. However, the reality of our country schooling has been pointed out that if a lot about the lack of character education related to the attitude of life care for others and feel a sense of responsibility. An individual is not necessarily emotional intelligence There are side out, as well as grow into adults, schools are obliged to teach a variety of methods associated with it. Nevertheless, education is not of the country beyond the formal excessive administrative work or other activities due to the process of character education to neglect, including the work of teachers. Therefore, students brought the expansion of the act that should not, and eventually lead to serious social issues that directly harm others, such as school violence. Therefore, students brought the expansion of the act that should not, and eventually lead to serious social issues that directly harm others, such as school violence. This study is based on an act of juvenile delinquency and criminology education was to refine the concept of toughness and validate the relationship between school violence through empirical research. Accordingly, from July 1, 2013 September 31, 2013 to 277 high schools across the country are attending the third year of the schools available for non-response and analysis of the students who participated in the admission and simulated typical presentation of K University in Gyeonggi-do not judge students in the final analysis, except for the data and data from a total of 1045 patients were utilized. As a result, many schools have experienced violence, male student work can be applied to a lot of rock school violence was experienced. Also, a lot of experience can be applied to a healthy student rock school violence, anger-control and empathy, this is considered a low student showed consciousness experienced school violence exerted.

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